initial_commit

Stable3DGen/hi3dgen/__init__.py

@@ -0,0 +1,36 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+#
+# Original file was released under MIT, with the full license text
+# available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+#
+# This modified file is released under the same license.
+from . import models
+from . import modules
+from . import pipelines
+from . import representations

Stable3DGen/hi3dgen/models/__init__.py

@@ -0,0 +1,98 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+import importlib
+
+__attributes = {
+    'SparseStructureEncoder': 'sparse_structure_vae',
+    'SparseStructureDecoder': 'sparse_structure_vae',
+    'SparseStructureFlowModel': 'sparse_structure_flow',
+    'SLatEncoder': 'structured_latent_vae',
+    'SLatGaussianDecoder': 'structured_latent_vae',
+    'SLatRadianceFieldDecoder': 'structured_latent_vae',
+    'SLatMeshDecoder': 'structured_latent_vae',
+    'SLatFlowModel': 'structured_latent_flow',
+}
+
+__submodules = []
+
+__all__ = list(__attributes.keys()) + __submodules
+
+def __getattr__(name):
+    if name not in globals():
+        if name in __attributes:
+            module_name = __attributes[name]
+            module = importlib.import_module(f".{module_name}", __name__)
+            globals()[name] = getattr(module, name)
+        elif name in __submodules:
+            module = importlib.import_module(f".{name}", __name__)
+            globals()[name] = module
+        else:
+            raise AttributeError(f"module {__name__} has no attribute {name}")
+    return globals()[name]
+
+
+def from_pretrained(path: str, **kwargs):
+    """
+    Load a model from a pretrained checkpoint.
+
+    Args:
+        path: The path to the checkpoint. Can be either local path or a Hugging Face model name.
+              NOTE: config file and model file should take the name f'{path}.json' and f'{path}.safetensors' respectively.
+        **kwargs: Additional arguments for the model constructor.
+    """
+    import os
+    import json
+    from safetensors.torch import load_file
+    is_local = os.path.exists(f"{path}.json") and os.path.exists(f"{path}.safetensors")
+
+    if is_local:
+        config_file = f"{path}.json"
+        model_file = f"{path}.safetensors"
+    else:
+        from huggingface_hub import hf_hub_download
+        path_parts = path.split('/')
+        repo_id = f'{path_parts[0]}/{path_parts[1]}'
+        model_name = '/'.join(path_parts[2:])
+        config_file = hf_hub_download(repo_id, f"{model_name}.json")
+        model_file = hf_hub_download(repo_id, f"{model_name}.safetensors")
+
+    with open(config_file, 'r') as f:
+        config = json.load(f)
+    model = __getattr__(config['name'])(**config['args'], **kwargs)
+    model.load_state_dict(load_file(model_file))
+
+    return model
+
+
+# For Pylance
+if __name__ == '__main__':
+    from .sparse_structure_vae import SparseStructureEncoder, SparseStructureDecoder
+    from .sparse_structure_flow import SparseStructureFlowModel
+    from .structured_latent_vae import SLatEncoder, SLatGaussianDecoder, SLatRadianceFieldDecoder, SLatMeshDecoder
+    from .structured_latent_flow import SLatFlowModel

Stable3DGen/hi3dgen/models/sparse_structure_flow.py

@@ -0,0 +1,228 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+import numpy as np
+from ..modules.utils import convert_module_to_f16, convert_module_to_f32
+from ..modules.transformer import AbsolutePositionEmbedder, ModulatedTransformerCrossBlock
+from ..modules.spatial import patchify, unpatchify
+
+
+class TimestepEmbedder(nn.Module):
+    """
+    Embeds scalar timesteps into vector representations.
+    """
+    def __init__(self, hidden_size, frequency_embedding_size=256):
+        super().__init__()
+        self.mlp = nn.Sequential(
+            nn.Linear(frequency_embedding_size, hidden_size, bias=True),
+            nn.SiLU(),
+            nn.Linear(hidden_size, hidden_size, bias=True),
+        )
+        self.frequency_embedding_size = frequency_embedding_size
+
+    @staticmethod
+    def timestep_embedding(t, dim, max_period=10000):
+        """
+        Create sinusoidal timestep embeddings.
+
+        Args:
+            t: a 1-D Tensor of N indices, one per batch element.
+                These may be fractional.
+            dim: the dimension of the output.
+            max_period: controls the minimum frequency of the embeddings.
+
+        Returns:
+            an (N, D) Tensor of positional embeddings.
+        """
+        # https://github.com/openai/glide-text2im/blob/main/glide_text2im/nn.py
+        half = dim // 2
+        freqs = torch.exp(
+            -np.log(max_period) * torch.arange(start=0, end=half, dtype=torch.float32) / half
+        ).to(device=t.device)
+        args = t[:, None].float() * freqs[None]
+        embedding = torch.cat([torch.cos(args), torch.sin(args)], dim=-1)
+        if dim % 2:
+            embedding = torch.cat([embedding, torch.zeros_like(embedding[:, :1])], dim=-1)
+        return embedding
+
+    def forward(self, t):
+        t_freq = self.timestep_embedding(t, self.frequency_embedding_size)
+        t_emb = self.mlp(t_freq)
+        return t_emb
+
+
+class SparseStructureFlowModel(nn.Module):
+    def __init__(
+        self,
+        resolution: int,
+        in_channels: int,
+        model_channels: int,
+        cond_channels: int,
+        out_channels: int,
+        num_blocks: int,
+        num_heads: Optional[int] = None,
+        num_head_channels: Optional[int] = 64,
+        mlp_ratio: float = 4,
+        patch_size: int = 2,
+        pe_mode: Literal["ape", "rope"] = "ape",
+        use_fp16: bool = False,
+        use_checkpoint: bool = False,
+        share_mod: bool = False,
+        qk_rms_norm: bool = False,
+        qk_rms_norm_cross: bool = False,
+    ):
+        super().__init__()
+        self.resolution = resolution
+        self.in_channels = in_channels
+        self.model_channels = model_channels
+        self.cond_channels = cond_channels
+        self.out_channels = out_channels
+        self.num_blocks = num_blocks
+        self.num_heads = num_heads or model_channels // num_head_channels
+        self.mlp_ratio = mlp_ratio
+        self.patch_size = patch_size
+        self.pe_mode = pe_mode
+        self.use_fp16 = use_fp16
+        self.use_checkpoint = use_checkpoint
+        self.share_mod = share_mod
+        self.qk_rms_norm = qk_rms_norm
+        self.qk_rms_norm_cross = qk_rms_norm_cross
+        self.dtype = torch.float16 if use_fp16 else torch.float32
+
+        self.t_embedder = TimestepEmbedder(model_channels)
+        if share_mod:
+            self.adaLN_modulation = nn.Sequential(
+                nn.SiLU(),
+                nn.Linear(model_channels, 6 * model_channels, bias=True)
+            )
+
+        if pe_mode == "ape":
+            pos_embedder = AbsolutePositionEmbedder(model_channels, 3)
+            coords = torch.meshgrid(*[torch.arange(res, device=self.device) for res in [resolution // patch_size] * 3], indexing='ij')
+            coords = torch.stack(coords, dim=-1).reshape(-1, 3)
+            pos_emb = pos_embedder(coords)
+            self.register_buffer("pos_emb", pos_emb)
+
+        self.input_layer = nn.Linear(in_channels * patch_size**3, model_channels)
+            
+        self.blocks = nn.ModuleList([
+            ModulatedTransformerCrossBlock(
+                model_channels,
+                cond_channels,
+                num_heads=self.num_heads,
+                mlp_ratio=self.mlp_ratio,
+                attn_mode='full',
+                use_checkpoint=self.use_checkpoint,
+                use_rope=(pe_mode == "rope"),
+                share_mod=share_mod,
+                qk_rms_norm=self.qk_rms_norm,
+                qk_rms_norm_cross=self.qk_rms_norm_cross,
+            )
+            for _ in range(num_blocks)
+        ])
+
+        self.out_layer = nn.Linear(model_channels, out_channels * patch_size**3)
+
+        self.initialize_weights()
+        if use_fp16:
+            self.convert_to_fp16()
+
+    @property
+    def device(self) -> torch.device:
+        """
+        Return the device of the model.
+        """
+        return next(self.parameters()).device
+
+    def convert_to_fp16(self) -> None:
+        """
+        Convert the torso of the model to float16.
+        """
+        self.blocks.apply(convert_module_to_f16)
+
+    def convert_to_fp32(self) -> None:
+        """
+        Convert the torso of the model to float32.
+        """
+        self.blocks.apply(convert_module_to_f32)
+
+    def initialize_weights(self) -> None:
+        # Initialize transformer layers:
+        def _basic_init(module):
+            if isinstance(module, nn.Linear):
+                torch.nn.init.xavier_uniform_(module.weight)
+                if module.bias is not None:
+                    nn.init.constant_(module.bias, 0)
+        self.apply(_basic_init)
+
+        # Initialize timestep embedding MLP:
+        nn.init.normal_(self.t_embedder.mlp[0].weight, std=0.02)
+        nn.init.normal_(self.t_embedder.mlp[2].weight, std=0.02)
+
+        # Zero-out adaLN modulation layers in DiT blocks:
+        if self.share_mod:
+            nn.init.constant_(self.adaLN_modulation[-1].weight, 0)
+            nn.init.constant_(self.adaLN_modulation[-1].bias, 0)
+        else:
+            for block in self.blocks:
+                nn.init.constant_(block.adaLN_modulation[-1].weight, 0)
+                nn.init.constant_(block.adaLN_modulation[-1].bias, 0)
+
+        # Zero-out output layers:
+        nn.init.constant_(self.out_layer.weight, 0)
+        nn.init.constant_(self.out_layer.bias, 0)
+
+    def forward(self, x: torch.Tensor, t: torch.Tensor, cond: torch.Tensor) -> torch.Tensor:
+        assert [*x.shape] == [x.shape[0], self.in_channels, *[self.resolution] * 3], \
+                f"Input shape mismatch, got {x.shape}, expected {[x.shape[0], self.in_channels, *[self.resolution] * 3]}"
+
+        h = patchify(x, self.patch_size)
+        h = h.view(*h.shape[:2], -1).permute(0, 2, 1).contiguous()
+
+        h = self.input_layer(h)
+        h = h + self.pos_emb[None]
+        t_emb = self.t_embedder(t)
+        if self.share_mod:
+            t_emb = self.adaLN_modulation(t_emb)
+        t_emb = t_emb.type(self.dtype)
+        h = h.type(self.dtype)
+        cond = cond.type(self.dtype)
+        for block in self.blocks:
+            h = block(h, t_emb, cond)
+        h = h.type(x.dtype)
+        h = F.layer_norm(h, h.shape[-1:])
+        h = self.out_layer(h)
+
+        h = h.permute(0, 2, 1).view(h.shape[0], h.shape[2], *[self.resolution // self.patch_size] * 3)
+        h = unpatchify(h, self.patch_size).contiguous()
+
+        return h

Stable3DGen/hi3dgen/models/sparse_structure_vae.py

@@ -0,0 +1,334 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from ..modules.norm import GroupNorm32, ChannelLayerNorm32
+from ..modules.spatial import pixel_shuffle_3d
+from ..modules.utils import zero_module, convert_module_to_f16, convert_module_to_f32
+
+
+def norm_layer(norm_type: str, *args, **kwargs) -> nn.Module:
+    """
+    Return a normalization layer.
+    """
+    if norm_type == "group":
+        return GroupNorm32(32, *args, **kwargs)
+    elif norm_type == "layer":
+        return ChannelLayerNorm32(*args, **kwargs)
+    else:
+        raise ValueError(f"Invalid norm type {norm_type}")
+
+
+class ResBlock3d(nn.Module):
+    def __init__(
+        self,
+        channels: int,
+        out_channels: Optional[int] = None,
+        norm_type: Literal["group", "layer"] = "layer",
+    ):
+        super().__init__()
+        self.channels = channels
+        self.out_channels = out_channels or channels
+
+        self.norm1 = norm_layer(norm_type, channels)
+        self.norm2 = norm_layer(norm_type, self.out_channels)
+        self.conv1 = nn.Conv3d(channels, self.out_channels, 3, padding=1)
+        self.conv2 = zero_module(nn.Conv3d(self.out_channels, self.out_channels, 3, padding=1))
+        self.skip_connection = nn.Conv3d(channels, self.out_channels, 1) if channels != self.out_channels else nn.Identity()
+    
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        h = self.norm1(x)
+        h = F.silu(h)
+        h = self.conv1(h)
+        h = self.norm2(h)
+        h = F.silu(h)
+        h = self.conv2(h)
+        h = h + self.skip_connection(x)
+        return h
+
+
+class DownsampleBlock3d(nn.Module):
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: int,
+        mode: Literal["conv", "avgpool"] = "conv",
+    ):
+        assert mode in ["conv", "avgpool"], f"Invalid mode {mode}"
+
+        super().__init__()
+        self.in_channels = in_channels
+        self.out_channels = out_channels
+
+        if mode == "conv":
+            self.conv = nn.Conv3d(in_channels, out_channels, 2, stride=2)
+        elif mode == "avgpool":
+            assert in_channels == out_channels, "Pooling mode requires in_channels to be equal to out_channels"
+
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        if hasattr(self, "conv"):
+            return self.conv(x)
+        else:
+            return F.avg_pool3d(x, 2)
+
+
+class UpsampleBlock3d(nn.Module):
+    def __init__(
+        self,
+        in_channels: int,
+        out_channels: int,
+        mode: Literal["conv", "nearest"] = "conv",
+    ):
+        assert mode in ["conv", "nearest"], f"Invalid mode {mode}"
+
+        super().__init__()
+        self.in_channels = in_channels
+        self.out_channels = out_channels
+
+        if mode == "conv":
+            self.conv = nn.Conv3d(in_channels, out_channels*8, 3, padding=1)
+        elif mode == "nearest":
+            assert in_channels == out_channels, "Nearest mode requires in_channels to be equal to out_channels"
+
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        if hasattr(self, "conv"):
+            x = self.conv(x)
+            return pixel_shuffle_3d(x, 2)
+        else:
+            return F.interpolate(x, scale_factor=2, mode="nearest")
+        
+
+class SparseStructureEncoder(nn.Module):
+    """
+    Encoder for Sparse Structure (\mathcal{E}_S in the paper Sec. 3.3).
+    
+    Args:
+        in_channels (int): Channels of the input.
+        latent_channels (int): Channels of the latent representation.
+        num_res_blocks (int): Number of residual blocks at each resolution.
+        channels (List[int]): Channels of the encoder blocks.
+        num_res_blocks_middle (int): Number of residual blocks in the middle.
+        norm_type (Literal["group", "layer"]): Type of normalization layer.
+        use_fp16 (bool): Whether to use FP16.
+    """
+    def __init__(
+        self,
+        in_channels: int,
+        latent_channels: int,
+        num_res_blocks: int,
+        channels: List[int],
+        num_res_blocks_middle: int = 2,
+        norm_type: Literal["group", "layer"] = "layer",
+        use_fp16: bool = False,
+    ):
+        super().__init__()
+        self.in_channels = in_channels
+        self.latent_channels = latent_channels
+        self.num_res_blocks = num_res_blocks
+        self.channels = channels
+        self.num_res_blocks_middle = num_res_blocks_middle
+        self.norm_type = norm_type
+        self.use_fp16 = use_fp16
+        self.dtype = torch.float16 if use_fp16 else torch.float32
+
+        self.input_layer = nn.Conv3d(in_channels, channels[0], 3, padding=1)
+
+        self.blocks = nn.ModuleList([])
+        for i, ch in enumerate(channels):
+            self.blocks.extend([
+                ResBlock3d(ch, ch)
+                for _ in range(num_res_blocks)
+            ])
+            if i < len(channels) - 1:
+                self.blocks.append(
+                    DownsampleBlock3d(ch, channels[i+1])
+                )
+        
+        self.middle_block = nn.Sequential(*[
+            ResBlock3d(channels[-1], channels[-1])
+            for _ in range(num_res_blocks_middle)
+        ])
+
+        self.out_layer = nn.Sequential(
+            norm_layer(norm_type, channels[-1]),
+            nn.SiLU(),
+            nn.Conv3d(channels[-1], latent_channels*2, 3, padding=1)
+        )
+
+        if use_fp16:
+            self.convert_to_fp16()
+
+    @property
+    def device(self) -> torch.device:
+        """
+        Return the device of the model.
+        """
+        return next(self.parameters()).device
+
+    def convert_to_fp16(self) -> None:
+        """
+        Convert the torso of the model to float16.
+        """
+        self.use_fp16 = True
+        self.dtype = torch.float16
+        self.blocks.apply(convert_module_to_f16)
+        self.middle_block.apply(convert_module_to_f16)
+
+    def convert_to_fp32(self) -> None:
+        """
+        Convert the torso of the model to float32.
+        """
+        self.use_fp16 = False
+        self.dtype = torch.float32
+        self.blocks.apply(convert_module_to_f32)
+        self.middle_block.apply(convert_module_to_f32)
+
+    def forward(self, x: torch.Tensor, sample_posterior: bool = False, return_raw: bool = False) -> torch.Tensor:
+        h = self.input_layer(x)
+        h = h.type(self.dtype)
+
+        for block in self.blocks:
+            h = block(h)
+        h = self.middle_block(h)
+
+        h = h.type(x.dtype)
+        h = self.out_layer(h)
+
+        mean, logvar = h.chunk(2, dim=1)
+
+        if sample_posterior:
+            std = torch.exp(0.5 * logvar)
+            z = mean + std * torch.randn_like(std)
+        else:
+            z = mean
+            
+        if return_raw:
+            return z, mean, logvar
+        return z
+        
+
+class SparseStructureDecoder(nn.Module):
+    """
+    Decoder for Sparse Structure (\mathcal{D}_S in the paper Sec. 3.3).
+    
+    Args:
+        out_channels (int): Channels of the output.
+        latent_channels (int): Channels of the latent representation.
+        num_res_blocks (int): Number of residual blocks at each resolution.
+        channels (List[int]): Channels of the decoder blocks.
+        num_res_blocks_middle (int): Number of residual blocks in the middle.
+        norm_type (Literal["group", "layer"]): Type of normalization layer.
+        use_fp16 (bool): Whether to use FP16.
+    """ 
+    def __init__(
+        self,
+        out_channels: int,
+        latent_channels: int,
+        num_res_blocks: int,
+        channels: List[int],
+        num_res_blocks_middle: int = 2,
+        norm_type: Literal["group", "layer"] = "layer",
+        use_fp16: bool = False,
+    ):
+        super().__init__()
+        self.out_channels = out_channels
+        self.latent_channels = latent_channels
+        self.num_res_blocks = num_res_blocks
+        self.channels = channels
+        self.num_res_blocks_middle = num_res_blocks_middle
+        self.norm_type = norm_type
+        self.use_fp16 = use_fp16
+        self.dtype = torch.float16 if use_fp16 else torch.float32
+
+        self.input_layer = nn.Conv3d(latent_channels, channels[0], 3, padding=1)
+
+        self.middle_block = nn.Sequential(*[
+            ResBlock3d(channels[0], channels[0])
+            for _ in range(num_res_blocks_middle)
+        ])
+
+        self.blocks = nn.ModuleList([])
+        for i, ch in enumerate(channels):
+            self.blocks.extend([
+                ResBlock3d(ch, ch)
+                for _ in range(num_res_blocks)
+            ])
+            if i < len(channels) - 1:
+                self.blocks.append(
+                    UpsampleBlock3d(ch, channels[i+1])
+                )
+
+        self.out_layer = nn.Sequential(
+            norm_layer(norm_type, channels[-1]),
+            nn.SiLU(),
+            nn.Conv3d(channels[-1], out_channels, 3, padding=1)
+        )
+
+        if use_fp16:
+            self.convert_to_fp16()
+
+    @property
+    def device(self) -> torch.device:
+        """
+        Return the device of the model.
+        """
+        return next(self.parameters()).device
+    
+    def convert_to_fp16(self) -> None:
+        """
+        Convert the torso of the model to float16.
+        """
+        self.use_fp16 = True
+        self.dtype = torch.float16
+        self.blocks.apply(convert_module_to_f16)
+        self.middle_block.apply(convert_module_to_f16)
+
+    def convert_to_fp32(self) -> None:
+        """
+        Convert the torso of the model to float32.
+        """
+        self.use_fp16 = False
+        self.dtype = torch.float32
+        self.blocks.apply(convert_module_to_f32)
+        self.middle_block.apply(convert_module_to_f32)
+    
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        h = self.input_layer(x)
+        
+        h = h.type(self.dtype)
+                
+        h = self.middle_block(h)
+        for block in self.blocks:
+            h = block(h)
+
+        h = h.type(x.dtype)
+        h = self.out_layer(h)
+        return h

Stable3DGen/hi3dgen/models/structured_latent_flow.py

@@ -0,0 +1,290 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+import numpy as np
+from ..modules.utils import zero_module, convert_module_to_f16, convert_module_to_f32
+from ..modules.transformer import AbsolutePositionEmbedder
+from ..modules.norm import LayerNorm32
+from ..modules import sparse as sp
+from ..modules.sparse.transformer import ModulatedSparseTransformerCrossBlock
+from .sparse_structure_flow import TimestepEmbedder
+
+
+class SparseResBlock3d(nn.Module):
+    def __init__(
+        self,
+        channels: int,
+        emb_channels: int,
+        out_channels: Optional[int] = None,
+        downsample: bool = False,
+        upsample: bool = False,
+    ):
+        super().__init__()
+        self.channels = channels
+        self.emb_channels = emb_channels
+        self.out_channels = out_channels or channels
+        self.downsample = downsample
+        self.upsample = upsample
+        
+        assert not (downsample and upsample), "Cannot downsample and upsample at the same time"
+
+        self.norm1 = LayerNorm32(channels, elementwise_affine=True, eps=1e-6)
+        self.norm2 = LayerNorm32(self.out_channels, elementwise_affine=False, eps=1e-6)
+        self.conv1 = sp.SparseConv3d(channels, self.out_channels, 3)
+        self.conv2 = zero_module(sp.SparseConv3d(self.out_channels, self.out_channels, 3))
+        self.emb_layers = nn.Sequential(
+            nn.SiLU(),
+            nn.Linear(emb_channels, 2 * self.out_channels, bias=True),
+        )
+        self.skip_connection = sp.SparseLinear(channels, self.out_channels) if channels != self.out_channels else nn.Identity()
+        self.updown = None
+        if self.downsample:
+            self.updown = sp.SparseDownsample(2)
+        elif self.upsample:
+            self.updown = sp.SparseUpsample(2)
+
+    def _updown(self, x: sp.SparseTensor) -> sp.SparseTensor:
+        if self.updown is not None:
+            x = self.updown(x)
+        return x
+
+    def forward(self, x: sp.SparseTensor, emb: torch.Tensor) -> sp.SparseTensor:
+        emb_out = self.emb_layers(emb).type(x.dtype)
+        scale, shift = torch.chunk(emb_out, 2, dim=1)
+
+        x = self._updown(x)
+        h = x.replace(self.norm1(x.feats))
+        h = h.replace(F.silu(h.feats))
+        h = self.conv1(h)
+        h = h.replace(self.norm2(h.feats)) * (1 + scale) + shift
+        h = h.replace(F.silu(h.feats))
+        h = self.conv2(h)
+        h = h + self.skip_connection(x)
+
+        return h
+    
+
+class SLatFlowModel(nn.Module):
+    def __init__(
+        self,
+        resolution: int,
+        in_channels: int,
+        model_channels: int,
+        cond_channels: int,
+        out_channels: int,
+        num_blocks: int,
+        num_heads: Optional[int] = None,
+        num_head_channels: Optional[int] = 64,
+        mlp_ratio: float = 4,
+        patch_size: int = 2,
+        num_io_res_blocks: int = 2,
+        io_block_channels: List[int] = None,
+        pe_mode: Literal["ape", "rope"] = "ape",
+        use_fp16: bool = False,
+        use_checkpoint: bool = False,
+        use_skip_connection: bool = True,
+        share_mod: bool = False,
+        qk_rms_norm: bool = False,
+        qk_rms_norm_cross: bool = False,
+    ):
+        super().__init__()
+        self.resolution = resolution
+        self.in_channels = in_channels
+        self.model_channels = model_channels
+        self.cond_channels = cond_channels
+        self.out_channels = out_channels
+        self.num_blocks = num_blocks
+        self.num_heads = num_heads or model_channels // num_head_channels
+        self.mlp_ratio = mlp_ratio
+        self.patch_size = patch_size
+        self.num_io_res_blocks = num_io_res_blocks
+        self.io_block_channels = io_block_channels
+        self.pe_mode = pe_mode
+        self.use_fp16 = use_fp16
+        self.use_checkpoint = use_checkpoint
+        self.use_skip_connection = use_skip_connection
+        self.share_mod = share_mod
+        self.qk_rms_norm = qk_rms_norm
+        self.qk_rms_norm_cross = qk_rms_norm_cross
+        self.dtype = torch.float16 if use_fp16 else torch.float32
+
+        assert int(np.log2(patch_size)) == np.log2(patch_size), "Patch size must be a power of 2"
+        assert np.log2(patch_size) == len(io_block_channels), "Number of IO ResBlocks must match the number of stages"
+
+        self.t_embedder = TimestepEmbedder(model_channels)
+        if share_mod:
+            self.adaLN_modulation = nn.Sequential(
+                nn.SiLU(),
+                nn.Linear(model_channels, 6 * model_channels, bias=True)
+            )
+
+        if pe_mode == "ape":
+            self.pos_embedder = AbsolutePositionEmbedder(model_channels)
+
+        self.input_layer = sp.SparseLinear(in_channels, io_block_channels[0])
+        self.input_blocks = nn.ModuleList([])
+        for chs, next_chs in zip(io_block_channels, io_block_channels[1:] + [model_channels]):
+            self.input_blocks.extend([
+                SparseResBlock3d(
+                    chs,
+                    model_channels,
+                    out_channels=chs,
+                )
+                for _ in range(num_io_res_blocks-1)
+            ])
+            self.input_blocks.append(
+                SparseResBlock3d(
+                    chs,
+                    model_channels,
+                    out_channels=next_chs,
+                    downsample=True,
+                )
+            )
+            
+        self.blocks = nn.ModuleList([
+            ModulatedSparseTransformerCrossBlock(
+                model_channels,
+                cond_channels,
+                num_heads=self.num_heads,
+                mlp_ratio=self.mlp_ratio,
+                attn_mode='full',
+                use_checkpoint=self.use_checkpoint,
+                use_rope=(pe_mode == "rope"),
+                share_mod=self.share_mod,
+                qk_rms_norm=self.qk_rms_norm,
+                qk_rms_norm_cross=self.qk_rms_norm_cross,
+            )
+            for _ in range(num_blocks)
+        ])
+
+        self.out_blocks = nn.ModuleList([])
+        for chs, prev_chs in zip(reversed(io_block_channels), [model_channels] + list(reversed(io_block_channels[1:]))):
+            self.out_blocks.append(
+                SparseResBlock3d(
+                    prev_chs * 2 if self.use_skip_connection else prev_chs,
+                    model_channels,
+                    out_channels=chs,
+                    upsample=True,
+                )
+            )
+            self.out_blocks.extend([
+                SparseResBlock3d(
+                    chs * 2 if self.use_skip_connection else chs,
+                    model_channels,
+                    out_channels=chs,
+                )
+                for _ in range(num_io_res_blocks-1)
+            ])
+        self.out_layer = sp.SparseLinear(io_block_channels[0], out_channels)
+
+        self.initialize_weights()
+        if use_fp16:
+            self.convert_to_fp16()
+
+    @property
+    def device(self) -> torch.device:
+        """
+        Return the device of the model.
+        """
+        return next(self.parameters()).device
+
+    def convert_to_fp16(self) -> None:
+        """
+        Convert the torso of the model to float16.
+        """
+        self.input_blocks.apply(convert_module_to_f16)
+        self.blocks.apply(convert_module_to_f16)
+        self.out_blocks.apply(convert_module_to_f16)
+
+    def convert_to_fp32(self) -> None:
+        """
+        Convert the torso of the model to float32.
+        """
+        self.input_blocks.apply(convert_module_to_f32)
+        self.blocks.apply(convert_module_to_f32)
+        self.out_blocks.apply(convert_module_to_f32)
+
+    def initialize_weights(self) -> None:
+        # Initialize transformer layers:
+        def _basic_init(module):
+            if isinstance(module, nn.Linear):
+                torch.nn.init.xavier_uniform_(module.weight)
+                if module.bias is not None:
+                    nn.init.constant_(module.bias, 0)
+        self.apply(_basic_init)
+
+        # Initialize timestep embedding MLP:
+        nn.init.normal_(self.t_embedder.mlp[0].weight, std=0.02)
+        nn.init.normal_(self.t_embedder.mlp[2].weight, std=0.02)
+
+        # Zero-out adaLN modulation layers in DiT blocks:
+        if self.share_mod:
+            nn.init.constant_(self.adaLN_modulation[-1].weight, 0)
+            nn.init.constant_(self.adaLN_modulation[-1].bias, 0)
+        else:
+            for block in self.blocks:
+                nn.init.constant_(block.adaLN_modulation[-1].weight, 0)
+                nn.init.constant_(block.adaLN_modulation[-1].bias, 0)
+
+        # Zero-out output layers:
+        nn.init.constant_(self.out_layer.weight, 0)
+        nn.init.constant_(self.out_layer.bias, 0)
+
+    def forward(self, x: sp.SparseTensor, t: torch.Tensor, cond: torch.Tensor) -> sp.SparseTensor:
+        h = self.input_layer(x).type(self.dtype)
+        t_emb = self.t_embedder(t)
+        if self.share_mod:
+            t_emb = self.adaLN_modulation(t_emb)
+        t_emb = t_emb.type(self.dtype)
+        cond = cond.type(self.dtype)
+
+        skips = []
+        # pack with input blocks
+        for block in self.input_blocks:
+            h = block(h, t_emb)
+            skips.append(h.feats)
+        
+        if self.pe_mode == "ape":
+            h = h + self.pos_embedder(h.coords[:, 1:]).type(self.dtype)
+        for block in self.blocks:
+            h = block(h, t_emb, cond)
+
+        # unpack with output blocks
+        for block, skip in zip(self.out_blocks, reversed(skips)):
+            if self.use_skip_connection:
+                h = block(h.replace(torch.cat([h.feats, skip], dim=1)), t_emb)
+            else:
+                h = block(h, t_emb)
+
+        h = h.replace(F.layer_norm(h.feats, h.feats.shape[-1:]))
+        h = self.out_layer(h.type(x.dtype))
+        return h

Stable3DGen/hi3dgen/models/structured_latent_vae/__init__.py

@@ -0,0 +1,30 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from .encoder import SLatEncoder
+from .decoder_mesh import SLatMeshDecoder

Stable3DGen/hi3dgen/models/structured_latent_vae/base.py

@@ -0,0 +1,145 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from typing import *
+import torch
+import torch.nn as nn
+from ...modules.utils import convert_module_to_f16, convert_module_to_f32
+from ...modules import sparse as sp
+from ...modules.transformer import AbsolutePositionEmbedder
+from ...modules.sparse.transformer import SparseTransformerBlock
+
+
+def block_attn_config(self):
+    """
+    Return the attention configuration of the model.
+    """
+    for i in range(self.num_blocks):
+        if self.attn_mode == "shift_window":
+            yield "serialized", self.window_size, 0, (16 * (i % 2),) * 3, sp.SerializeMode.Z_ORDER
+        elif self.attn_mode == "shift_sequence":
+            yield "serialized", self.window_size, self.window_size // 2 * (i % 2), (0, 0, 0), sp.SerializeMode.Z_ORDER
+        elif self.attn_mode == "shift_order":
+            yield "serialized", self.window_size, 0, (0, 0, 0), sp.SerializeModes[i % 4]
+        elif self.attn_mode == "full":
+            yield "full", None, None, None, None
+        elif self.attn_mode == "swin":
+            yield "windowed", self.window_size, None, self.window_size // 2 * (i % 2), None
+
+
+class SparseTransformerBase(nn.Module):
+    """
+    Sparse Transformer without output layers.
+    Serve as the base class for encoder and decoder.
+    """
+    def __init__(
+        self,
+        in_channels: int,
+        model_channels: int,
+        num_blocks: int,
+        num_heads: Optional[int] = None,
+        num_head_channels: Optional[int] = 64,
+        mlp_ratio: float = 4.0,
+        attn_mode: Literal["full", "shift_window", "shift_sequence", "shift_order", "swin"] = "full",
+        window_size: Optional[int] = None,
+        pe_mode: Literal["ape", "rope"] = "ape",
+        use_fp16: bool = False,
+        use_checkpoint: bool = False,
+        qk_rms_norm: bool = False,
+    ):
+        super().__init__()
+        self.in_channels = in_channels
+        self.model_channels = model_channels
+        self.num_blocks = num_blocks
+        self.window_size = window_size
+        self.num_heads = num_heads or model_channels // num_head_channels
+        self.mlp_ratio = mlp_ratio
+        self.attn_mode = attn_mode
+        self.pe_mode = pe_mode
+        self.use_fp16 = use_fp16
+        self.use_checkpoint = use_checkpoint
+        self.qk_rms_norm = qk_rms_norm
+        self.dtype = torch.float16 if use_fp16 else torch.float32
+
+        if pe_mode == "ape":
+            self.pos_embedder = AbsolutePositionEmbedder(model_channels)
+
+        self.input_layer = sp.SparseLinear(in_channels, model_channels)
+        self.blocks = nn.ModuleList([
+            SparseTransformerBlock(
+                model_channels,
+                num_heads=self.num_heads,
+                mlp_ratio=self.mlp_ratio,
+                attn_mode=attn_mode,
+                window_size=window_size,
+                shift_sequence=shift_sequence,
+                shift_window=shift_window,
+                serialize_mode=serialize_mode,
+                use_checkpoint=self.use_checkpoint,
+                use_rope=(pe_mode == "rope"),
+                qk_rms_norm=self.qk_rms_norm,
+            )
+            for attn_mode, window_size, shift_sequence, shift_window, serialize_mode in block_attn_config(self)
+        ])
+
+    @property
+    def device(self) -> torch.device:
+        """
+        Return the device of the model.
+        """
+        return next(self.parameters()).device
+
+    def convert_to_fp16(self) -> None:
+        """
+        Convert the torso of the model to float16.
+        """
+        self.blocks.apply(convert_module_to_f16)
+
+    def convert_to_fp32(self) -> None:
+        """
+        Convert the torso of the model to float32.
+        """
+        self.blocks.apply(convert_module_to_f32)
+
+    def initialize_weights(self) -> None:
+        # Initialize transformer layers:
+        def _basic_init(module):
+            if isinstance(module, nn.Linear):
+                torch.nn.init.xavier_uniform_(module.weight)
+                if module.bias is not None:
+                    nn.init.constant_(module.bias, 0)
+        self.apply(_basic_init)
+
+    def forward(self, x: sp.SparseTensor) -> sp.SparseTensor:
+        h = self.input_layer(x)
+        if self.pe_mode == "ape":
+            h = h + self.pos_embedder(x.coords[:, 1:])
+        h = h.type(self.dtype)
+        for block in self.blocks:
+            h = block(h)
+        return h

Stable3DGen/hi3dgen/models/structured_latent_vae/decoder_mesh.py

@@ -0,0 +1,195 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+import numpy as np
+from ...modules.utils import zero_module, convert_module_to_f16, convert_module_to_f32
+from ...modules import sparse as sp
+from .base import SparseTransformerBase
+from ...representations import MeshExtractResult
+from ...representations.mesh import SparseFeatures2Mesh
+
+
+class SparseSubdivideBlock3d(nn.Module):
+    """
+    A 3D subdivide block that can subdivide the sparse tensor.
+
+    Args:
+        channels: channels in the inputs and outputs.
+        out_channels: if specified, the number of output channels.
+        num_groups: the number of groups for the group norm.
+    """
+    def __init__(
+        self,
+        channels: int,
+        resolution: int,
+        out_channels: Optional[int] = None,
+        num_groups: int = 32
+    ):
+        super().__init__()
+        self.channels = channels
+        self.resolution = resolution
+        self.out_resolution = resolution * 2
+        self.out_channels = out_channels or channels
+
+        self.act_layers = nn.Sequential(
+            sp.SparseGroupNorm32(num_groups, channels),
+            sp.SparseSiLU()
+        )
+        
+        self.sub = sp.SparseSubdivide()
+        
+        self.out_layers = nn.Sequential(
+            sp.SparseConv3d(channels, self.out_channels, 3, indice_key=f"res_{self.out_resolution}"),
+            sp.SparseGroupNorm32(num_groups, self.out_channels),
+            sp.SparseSiLU(),
+            zero_module(sp.SparseConv3d(self.out_channels, self.out_channels, 3, indice_key=f"res_{self.out_resolution}")),
+        )
+        
+        if self.out_channels == channels:
+            self.skip_connection = nn.Identity()
+        else:
+            self.skip_connection = sp.SparseConv3d(channels, self.out_channels, 1, indice_key=f"res_{self.out_resolution}")
+        
+    def forward(self, x: sp.SparseTensor) -> sp.SparseTensor:
+        """
+        Apply the block to a Tensor, conditioned on a timestep embedding.
+
+        Args:
+            x: an [N x C x ...] Tensor of features.
+        Returns:
+            an [N x C x ...] Tensor of outputs.
+        """
+        h = self.act_layers(x)
+        h = self.sub(h)
+        x = self.sub(x)
+        h = self.out_layers(h)
+        h = h + self.skip_connection(x)
+        return h
+
+
+class SLatMeshDecoder(SparseTransformerBase):
+    def __init__(
+        self,
+        resolution: int,
+        model_channels: int,
+        latent_channels: int,
+        num_blocks: int,
+        num_heads: Optional[int] = None,
+        num_head_channels: Optional[int] = 64,
+        mlp_ratio: float = 4,
+        attn_mode: Literal["full", "shift_window", "shift_sequence", "shift_order", "swin"] = "swin",
+        window_size: int = 8,
+        pe_mode: Literal["ape", "rope"] = "ape",
+        use_fp16: bool = False,
+        use_checkpoint: bool = False,
+        qk_rms_norm: bool = False,
+        representation_config: dict = None,
+    ):
+        super().__init__(
+            in_channels=latent_channels,
+            model_channels=model_channels,
+            num_blocks=num_blocks,
+            num_heads=num_heads,
+            num_head_channels=num_head_channels,
+            mlp_ratio=mlp_ratio,
+            attn_mode=attn_mode,
+            window_size=window_size,
+            pe_mode=pe_mode,
+            use_fp16=use_fp16,
+            use_checkpoint=use_checkpoint,
+            qk_rms_norm=qk_rms_norm,
+        )
+        self.resolution = resolution
+        self.rep_config = representation_config
+        self.mesh_extractor = SparseFeatures2Mesh(res=self.resolution*4, use_color=self.rep_config.get('use_color', False))
+        self.out_channels = self.mesh_extractor.feats_channels
+        self.upsample = nn.ModuleList([
+            SparseSubdivideBlock3d(
+                channels=model_channels,
+                resolution=resolution,
+                out_channels=model_channels // 4
+            ),
+            SparseSubdivideBlock3d(
+                channels=model_channels // 4,
+                resolution=resolution * 2,
+                out_channels=model_channels // 8
+            )
+        ])
+        self.out_layer = sp.SparseLinear(model_channels // 8, self.out_channels)
+
+        self.initialize_weights()
+        if use_fp16:
+            self.convert_to_fp16()
+
+    def initialize_weights(self) -> None:
+        super().initialize_weights()
+        # Zero-out output layers:
+        nn.init.constant_(self.out_layer.weight, 0)
+        nn.init.constant_(self.out_layer.bias, 0)
+
+    def convert_to_fp16(self) -> None:
+        """
+        Convert the torso of the model to float16.
+        """
+        super().convert_to_fp16()
+        self.upsample.apply(convert_module_to_f16)
+
+    def convert_to_fp32(self) -> None:
+        """
+        Convert the torso of the model to float32.
+        """
+        super().convert_to_fp32()
+        self.upsample.apply(convert_module_to_f32)  
+    
+    def to_representation(self, x: sp.SparseTensor) -> List[MeshExtractResult]:
+        """
+        Convert a batch of network outputs to 3D representations.
+
+        Args:
+            x: The [N x * x C] sparse tensor output by the network.
+
+        Returns:
+            list of representations
+        """
+        ret = []
+        for i in range(x.shape[0]):
+            mesh = self.mesh_extractor(x[i], training=self.training)
+            ret.append(mesh)
+        return ret
+
+    def forward(self, x: sp.SparseTensor) -> List[MeshExtractResult]:
+        h = super().forward(x)
+        for block in self.upsample:
+            h = block(h)
+        h = h.type(x.dtype)
+        h = self.out_layer(h)
+        return self.to_representation(h)

Stable3DGen/hi3dgen/models/structured_latent_vae/encoder.py

@@ -0,0 +1,100 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# Copyright (c) [2025] [Chongjie Ye] 
+# SPDX-License-Identifier: MIT
+# This file has been modified by Chongjie Ye on 2025/04/10
+# Original file was released under MIT, with the full license text # available at https://github.com/atong01/conditional-flow-matching/blob/1.0.7/LICENSE.
+# This modified file is released under the same license.
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from ...modules import sparse as sp
+from .base import SparseTransformerBase
+
+
+class SLatEncoder(SparseTransformerBase):
+    def __init__(
+        self,
+        resolution: int,
+        in_channels: int,
+        model_channels: int,
+        latent_channels: int,
+        num_blocks: int,
+        num_heads: Optional[int] = None,
+        num_head_channels: Optional[int] = 64,
+        mlp_ratio: float = 4,
+        attn_mode: Literal["full", "shift_window", "shift_sequence", "shift_order", "swin"] = "swin",
+        window_size: int = 8,
+        pe_mode: Literal["ape", "rope"] = "ape",
+        use_fp16: bool = False,
+        use_checkpoint: bool = False,
+        qk_rms_norm: bool = False,
+    ):
+        super().__init__(
+            in_channels=in_channels,
+            model_channels=model_channels,
+            num_blocks=num_blocks,
+            num_heads=num_heads,
+            num_head_channels=num_head_channels,
+            mlp_ratio=mlp_ratio,
+            attn_mode=attn_mode,
+            window_size=window_size,
+            pe_mode=pe_mode,
+            use_fp16=use_fp16,
+            use_checkpoint=use_checkpoint,
+            qk_rms_norm=qk_rms_norm,
+        )
+        self.resolution = resolution
+        self.out_layer = sp.SparseLinear(model_channels, 2 * latent_channels)
+
+        self.initialize_weights()
+        if use_fp16:
+            self.convert_to_fp16()
+
+    def initialize_weights(self) -> None:
+        super().initialize_weights()
+        # Zero-out output layers:
+        nn.init.constant_(self.out_layer.weight, 0)
+        nn.init.constant_(self.out_layer.bias, 0)
+
+    def forward(self, x: sp.SparseTensor, sample_posterior=True, return_raw=False):
+        h = super().forward(x)
+        h = h.type(x.dtype)
+        h = h.replace(F.layer_norm(h.feats, h.feats.shape[-1:]))
+        h = self.out_layer(h)
+        
+        # Sample from the posterior distribution
+        mean, logvar = h.feats.chunk(2, dim=-1)
+        if sample_posterior:
+            std = torch.exp(0.5 * logvar)
+            z = mean + std * torch.randn_like(std)
+        else:
+            z = mean
+        z = h.replace(z)
+            
+        if return_raw:
+            return z, mean, logvar
+        else:
+            return z

Stable3DGen/hi3dgen/modules/attention/__init__.py

@@ -0,0 +1,60 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+
+BACKEND = 'xformers' 
+DEBUG = False
+
+def __from_env():
+    import os
+    
+    global BACKEND
+    global DEBUG
+    
+    env_attn_backend = os.environ.get('ATTN_BACKEND')
+    env_sttn_debug = os.environ.get('ATTN_DEBUG')
+    
+    if env_attn_backend is not None and env_attn_backend in ['xformers', 'flash_attn', 'sdpa', 'naive']:
+        BACKEND = env_attn_backend
+    if env_sttn_debug is not None:
+        DEBUG = env_sttn_debug == '1'
+
+    print(f"[ATTENTION] Using backend: {BACKEND}")
+        
+
+__from_env()
+    
+
+def set_backend(backend: Literal['xformers', 'flash_attn']):
+    global BACKEND
+    BACKEND = backend
+
+def set_debug(debug: bool):
+    global DEBUG
+    DEBUG = debug
+
+
+from .full_attn import *
+from .modules import *

Stable3DGen/hi3dgen/modules/attention/full_attn.py

@@ -0,0 +1,164 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+import torch
+import math
+from . import DEBUG, BACKEND
+
+if BACKEND == 'xformers':
+    import xformers.ops as xops
+elif BACKEND == 'flash_attn':
+    import flash_attn
+elif BACKEND == 'sdpa':
+    from torch.nn.functional import scaled_dot_product_attention as sdpa
+elif BACKEND == 'naive':
+    pass
+else:
+    raise ValueError(f"Unknown attention backend: {BACKEND}")
+
+
+__all__ = [
+    'scaled_dot_product_attention',
+]
+
+
+def _naive_sdpa(q, k, v):
+    """
+    Naive implementation of scaled dot product attention.
+    """
+    q = q.permute(0, 2, 1, 3)   # [N, H, L, C]
+    k = k.permute(0, 2, 1, 3)   # [N, H, L, C]
+    v = v.permute(0, 2, 1, 3)   # [N, H, L, C]
+    scale_factor = 1 / math.sqrt(q.size(-1))
+    attn_weight = q @ k.transpose(-2, -1) * scale_factor
+    attn_weight = torch.softmax(attn_weight, dim=-1)
+    out = attn_weight @ v
+    out = out.permute(0, 2, 1, 3)   # [N, L, H, C]
+    return out
+
+
+@overload
+def scaled_dot_product_attention(qkv: torch.Tensor) -> torch.Tensor:
+    """
+    Apply scaled dot product attention.
+
+    Args:
+        qkv (torch.Tensor): A [N, L, 3, H, C] tensor containing Qs, Ks, and Vs.
+    """
+    ...
+
+@overload
+def scaled_dot_product_attention(q: torch.Tensor, kv: torch.Tensor) -> torch.Tensor:
+    """
+    Apply scaled dot product attention.
+
+    Args:
+        q (torch.Tensor): A [N, L, H, C] tensor containing Qs.
+        kv (torch.Tensor): A [N, L, 2, H, C] tensor containing Ks and Vs.
+    """
+    ...
+
+@overload
+def scaled_dot_product_attention(q: torch.Tensor, k: torch.Tensor, v: torch.Tensor) -> torch.Tensor:
+    """
+    Apply scaled dot product attention.
+
+    Args:
+        q (torch.Tensor): A [N, L, H, Ci] tensor containing Qs.
+        k (torch.Tensor): A [N, L, H, Ci] tensor containing Ks.
+        v (torch.Tensor): A [N, L, H, Co] tensor containing Vs.
+
+    Note:
+        k and v are assumed to have the same coordinate map.
+    """
+    ...
+
+def scaled_dot_product_attention(*args, **kwargs):
+    arg_names_dict = {
+        1: ['qkv'],
+        2: ['q', 'kv'],
+        3: ['q', 'k', 'v']
+    }
+    num_all_args = len(args) + len(kwargs)
+    assert num_all_args in arg_names_dict, f"Invalid number of arguments, got {num_all_args}, expected 1, 2, or 3"
+    for key in arg_names_dict[num_all_args][len(args):]:
+        assert key in kwargs, f"Missing argument {key}"
+
+    if num_all_args == 1:
+        qkv = args[0] if len(args) > 0 else kwargs['qkv']
+        assert len(qkv.shape) == 5 and qkv.shape[2] == 3, f"Invalid shape for qkv, got {qkv.shape}, expected [N, L, 3, H, C]"
+        device = qkv.device
+
+    elif num_all_args == 2:
+        q = args[0] if len(args) > 0 else kwargs['q']
+        kv = args[1] if len(args) > 1 else kwargs['kv']
+        assert q.shape[0] == kv.shape[0], f"Batch size mismatch, got {q.shape[0]} and {kv.shape[0]}"
+        assert len(q.shape) == 4, f"Invalid shape for q, got {q.shape}, expected [N, L, H, C]"
+        assert len(kv.shape) == 5, f"Invalid shape for kv, got {kv.shape}, expected [N, L, 2, H, C]"
+        device = q.device
+
+    elif num_all_args == 3:
+        q = args[0] if len(args) > 0 else kwargs['q']
+        k = args[1] if len(args) > 1 else kwargs['k']
+        v = args[2] if len(args) > 2 else kwargs['v']
+        assert q.shape[0] == k.shape[0] == v.shape[0], f"Batch size mismatch, got {q.shape[0]}, {k.shape[0]}, and {v.shape[0]}"
+        assert len(q.shape) == 4, f"Invalid shape for q, got {q.shape}, expected [N, L, H, Ci]"
+        assert len(k.shape) == 4, f"Invalid shape for k, got {k.shape}, expected [N, L, H, Ci]"
+        assert len(v.shape) == 4, f"Invalid shape for v, got {v.shape}, expected [N, L, H, Co]"
+        device = q.device    
+
+    if BACKEND == 'xformers':
+        if num_all_args == 1:
+            q, k, v = qkv.unbind(dim=2)
+        elif num_all_args == 2:
+            k, v = kv.unbind(dim=2)
+        out = xops.memory_efficient_attention(q, k, v)
+    elif BACKEND == 'flash_attn':
+        if num_all_args == 1:
+            out = flash_attn.flash_attn_qkvpacked_func(qkv)
+        elif num_all_args == 2:
+            out = flash_attn.flash_attn_kvpacked_func(q, kv)
+        elif num_all_args == 3:
+            out = flash_attn.flash_attn_func(q, k, v)
+    elif BACKEND == 'sdpa':
+        if num_all_args == 1:
+            q, k, v = qkv.unbind(dim=2)
+        elif num_all_args == 2:
+            k, v = kv.unbind(dim=2)
+        q = q.permute(0, 2, 1, 3)   # [N, H, L, C]
+        k = k.permute(0, 2, 1, 3)   # [N, H, L, C]
+        v = v.permute(0, 2, 1, 3)   # [N, H, L, C]
+        out = sdpa(q, k, v)         # [N, H, L, C]
+        out = out.permute(0, 2, 1, 3)   # [N, L, H, C]
+    elif BACKEND == 'naive':
+        if num_all_args == 1:
+            q, k, v = qkv.unbind(dim=2)
+        elif num_all_args == 2:
+            k, v = kv.unbind(dim=2)
+        out = _naive_sdpa(q, k, v)
+    else:
+        raise ValueError(f"Unknown attention module: {BACKEND}")
+    
+    return out

Stable3DGen/hi3dgen/modules/attention/modules.py

@@ -0,0 +1,170 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from .full_attn import scaled_dot_product_attention
+
+
+class MultiHeadRMSNorm(nn.Module):
+    def __init__(self, dim: int, heads: int):
+        super().__init__()
+        self.scale = dim ** 0.5
+        self.gamma = nn.Parameter(torch.ones(heads, dim))
+
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        return (F.normalize(x.float(), dim = -1) * self.gamma * self.scale).to(x.dtype)
+
+
+class RotaryPositionEmbedder(nn.Module):
+    def __init__(self, hidden_size: int, in_channels: int = 3):
+        super().__init__()
+        assert hidden_size % 2 == 0, "Hidden size must be divisible by 2"
+        self.hidden_size = hidden_size
+        self.in_channels = in_channels
+        self.freq_dim = hidden_size // in_channels // 2
+        self.freqs = torch.arange(self.freq_dim, dtype=torch.float32) / self.freq_dim
+        self.freqs = 1.0 / (10000 ** self.freqs)
+        
+    def _get_phases(self, indices: torch.Tensor) -> torch.Tensor:
+        self.freqs = self.freqs.to(indices.device)
+        phases = torch.outer(indices, self.freqs)
+        phases = torch.polar(torch.ones_like(phases), phases)
+        return phases
+        
+    def _rotary_embedding(self, x: torch.Tensor, phases: torch.Tensor) -> torch.Tensor:
+        x_complex = torch.view_as_complex(x.float().reshape(*x.shape[:-1], -1, 2))
+        x_rotated = x_complex * phases
+        x_embed = torch.view_as_real(x_rotated).reshape(*x_rotated.shape[:-1], -1).to(x.dtype)
+        return x_embed
+        
+    def forward(self, q: torch.Tensor, k: torch.Tensor, indices: Optional[torch.Tensor] = None) -> Tuple[torch.Tensor, torch.Tensor]:
+        """
+        Args:
+            q (sp.SparseTensor): [..., N, D] tensor of queries
+            k (sp.SparseTensor): [..., N, D] tensor of keys
+            indices (torch.Tensor): [..., N, C] tensor of spatial positions
+        """
+        if indices is None:
+            indices = torch.arange(q.shape[-2], device=q.device)
+            if len(q.shape) > 2:
+                indices = indices.unsqueeze(0).expand(q.shape[:-2] + (-1,))
+        
+        phases = self._get_phases(indices.reshape(-1)).reshape(*indices.shape[:-1], -1)
+        if phases.shape[1] < self.hidden_size // 2:
+            phases = torch.cat([phases, torch.polar(
+                torch.ones(*phases.shape[:-1], self.hidden_size // 2 - phases.shape[1], device=phases.device),
+                torch.zeros(*phases.shape[:-1], self.hidden_size // 2 - phases.shape[1], device=phases.device)
+            )], dim=-1)
+        q_embed = self._rotary_embedding(q, phases)
+        k_embed = self._rotary_embedding(k, phases)
+        return q_embed, k_embed
+    
+
+class MultiHeadAttention(nn.Module):
+    def __init__(
+        self,
+        channels: int,
+        num_heads: int,
+        ctx_channels: Optional[int]=None,
+        type: Literal["self", "cross"] = "self",
+        attn_mode: Literal["full", "windowed"] = "full",
+        window_size: Optional[int] = None,
+        shift_window: Optional[Tuple[int, int, int]] = None,
+        qkv_bias: bool = True,
+        use_rope: bool = False,
+        qk_rms_norm: bool = False,
+    ):
+        super().__init__()
+        assert channels % num_heads == 0
+        assert type in ["self", "cross"], f"Invalid attention type: {type}"
+        assert attn_mode in ["full", "windowed"], f"Invalid attention mode: {attn_mode}"
+        assert type == "self" or attn_mode == "full", "Cross-attention only supports full attention"
+        
+        if attn_mode == "windowed":
+            raise NotImplementedError("Windowed attention is not yet implemented")
+        
+        self.channels = channels
+        self.head_dim = channels // num_heads
+        self.ctx_channels = ctx_channels if ctx_channels is not None else channels
+        self.num_heads = num_heads
+        self._type = type
+        self.attn_mode = attn_mode
+        self.window_size = window_size
+        self.shift_window = shift_window
+        self.use_rope = use_rope
+        self.qk_rms_norm = qk_rms_norm
+
+        if self._type == "self":
+            self.to_qkv = nn.Linear(channels, channels * 3, bias=qkv_bias)
+        else:
+            self.to_q = nn.Linear(channels, channels, bias=qkv_bias)
+            self.to_kv = nn.Linear(self.ctx_channels, channels * 2, bias=qkv_bias)
+            
+        if self.qk_rms_norm:
+            self.q_rms_norm = MultiHeadRMSNorm(self.head_dim, num_heads)
+            self.k_rms_norm = MultiHeadRMSNorm(self.head_dim, num_heads)
+            
+        self.to_out = nn.Linear(channels, channels)
+
+        if use_rope:
+            self.rope = RotaryPositionEmbedder(channels)
+    
+    def forward(self, x: torch.Tensor, context: Optional[torch.Tensor] = None, indices: Optional[torch.Tensor] = None) -> torch.Tensor:
+        B, L, C = x.shape
+        if self._type == "self":
+            qkv = self.to_qkv(x)
+            qkv = qkv.reshape(B, L, 3, self.num_heads, -1)
+            if self.use_rope:
+                q, k, v = qkv.unbind(dim=2)
+                q, k = self.rope(q, k, indices)
+                qkv = torch.stack([q, k, v], dim=2)
+            if self.attn_mode == "full":
+                if self.qk_rms_norm:
+                    q, k, v = qkv.unbind(dim=2)
+                    q = self.q_rms_norm(q)
+                    k = self.k_rms_norm(k)
+                    h = scaled_dot_product_attention(q, k, v)
+                else:
+                    h = scaled_dot_product_attention(qkv)
+            elif self.attn_mode == "windowed":
+                raise NotImplementedError("Windowed attention is not yet implemented")
+        else:
+            Lkv = context.shape[1]
+            q = self.to_q(x)
+            kv = self.to_kv(context)
+            q = q.reshape(B, L, self.num_heads, -1)
+            kv = kv.reshape(B, Lkv, 2, self.num_heads, -1)
+            if self.qk_rms_norm:
+                q = self.q_rms_norm(q)
+                k, v = kv.unbind(dim=2)
+                k = self.k_rms_norm(k)
+                h = scaled_dot_product_attention(q, k, v)
+            else:
+                h = scaled_dot_product_attention(q, kv)
+        h = h.reshape(B, L, -1)
+        h = self.to_out(h)
+        return h

Stable3DGen/hi3dgen/modules/norm.py

@@ -0,0 +1,49 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+import torch
+import torch.nn as nn
+
+
+class LayerNorm32(nn.LayerNorm):
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        return super().forward(x.float()).type(x.dtype)
+    
+
+class GroupNorm32(nn.GroupNorm):
+    """
+    A GroupNorm layer that converts to float32 before the forward pass.
+    """
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        return super().forward(x.float()).type(x.dtype)
+    
+    
+class ChannelLayerNorm32(LayerNorm32):
+    def forward(self, x: torch.Tensor) -> torch.Tensor:
+        DIM = x.dim()
+        x = x.permute(0, *range(2, DIM), 1).contiguous()
+        x = super().forward(x)
+        x = x.permute(0, DIM-1, *range(1, DIM-1)).contiguous()
+        return x
+    

Stable3DGen/hi3dgen/modules/sparse/__init__.py

@@ -0,0 +1,126 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+
+BACKEND = 'spconv' 
+DEBUG = False
+ATTN = 'xformers'
+
+def __from_env():
+    import os
+    
+    global BACKEND
+    global DEBUG
+    global ATTN
+    
+    env_sparse_backend = os.environ.get('SPARSE_BACKEND')
+    env_sparse_debug = os.environ.get('SPARSE_DEBUG')
+    env_sparse_attn = os.environ.get('SPARSE_ATTN_BACKEND')
+    if env_sparse_attn is None:
+        env_sparse_attn = os.environ.get('ATTN_BACKEND')
+
+    if env_sparse_backend is not None and env_sparse_backend in ['spconv', 'torchsparse']:
+        BACKEND = env_sparse_backend
+    if env_sparse_debug is not None:
+        DEBUG = env_sparse_debug == '1'
+    if env_sparse_attn is not None and env_sparse_attn in ['xformers', 'flash_attn']:
+        ATTN = env_sparse_attn
+        
+    print(f"[SPARSE] Backend: {BACKEND}, Attention: {ATTN}")
+        
+
+__from_env()
+    
+
+def set_backend(backend: Literal['spconv', 'torchsparse']):
+    global BACKEND
+    BACKEND = backend
+
+def set_debug(debug: bool):
+    global DEBUG
+    DEBUG = debug
+
+def set_attn(attn: Literal['xformers', 'flash_attn']):
+    global ATTN
+    ATTN = attn
+    
+    
+import importlib
+
+__attributes = {
+    'SparseTensor': 'basic',
+    'sparse_batch_broadcast': 'basic',
+    'sparse_batch_op': 'basic',
+    'sparse_cat': 'basic',
+    'sparse_unbind': 'basic',
+    'SparseGroupNorm': 'norm',
+    'SparseLayerNorm': 'norm',
+    'SparseGroupNorm32': 'norm',
+    'SparseLayerNorm32': 'norm',
+    'SparseReLU': 'nonlinearity',
+    'SparseSiLU': 'nonlinearity',
+    'SparseGELU': 'nonlinearity',
+    'SparseActivation': 'nonlinearity',
+    'SparseLinear': 'linear',
+    'sparse_scaled_dot_product_attention': 'attention',
+    'SerializeMode': 'attention',
+    'sparse_serialized_scaled_dot_product_self_attention': 'attention',
+    'sparse_windowed_scaled_dot_product_self_attention': 'attention',
+    'SparseMultiHeadAttention': 'attention',
+    'SparseConv3d': 'conv',
+    'SparseInverseConv3d': 'conv',
+    'SparseDownsample': 'spatial',
+    'SparseUpsample': 'spatial',
+    'SparseSubdivide' : 'spatial'
+}
+
+__submodules = ['transformer']
+
+__all__ = list(__attributes.keys()) + __submodules
+
+def __getattr__(name):
+    if name not in globals():
+        if name in __attributes:
+            module_name = __attributes[name]
+            module = importlib.import_module(f".{module_name}", __name__)
+            globals()[name] = getattr(module, name)
+        elif name in __submodules:
+            module = importlib.import_module(f".{name}", __name__)
+            globals()[name] = module
+        else:
+            raise AttributeError(f"module {__name__} has no attribute {name}")
+    return globals()[name]
+
+
+# For Pylance
+if __name__ == '__main__':
+    from .basic import *
+    from .norm import *
+    from .nonlinearity import *
+    from .linear import *
+    from .attention import *
+    from .conv import *
+    from .spatial import *
+    import transformer

Stable3DGen/hi3dgen/modules/sparse/attention/__init__.py

@@ -0,0 +1,28 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from .full_attn import *
+from .serialized_attn import *
+from .windowed_attn import *
+from .modules import *

Stable3DGen/hi3dgen/modules/sparse/attention/full_attn.py

@@ -0,0 +1,239 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+import torch
+from .. import SparseTensor
+from .. import DEBUG, ATTN
+
+if ATTN == 'xformers':
+    import xformers.ops as xops
+elif ATTN == 'flash_attn':
+    import flash_attn
+else:
+    raise ValueError(f"Unknown attention module: {ATTN}")
+
+
+__all__ = [
+    'sparse_scaled_dot_product_attention',
+]
+
+
+@overload
+def sparse_scaled_dot_product_attention(qkv: SparseTensor) -> SparseTensor:
+    """
+    Apply scaled dot product attention to a sparse tensor.
+
+    Args:
+        qkv (SparseTensor): A [N, *, 3, H, C] sparse tensor containing Qs, Ks, and Vs.
+    """
+    ...
+
+@overload
+def sparse_scaled_dot_product_attention(q: SparseTensor, kv: Union[SparseTensor, torch.Tensor]) -> SparseTensor:
+    """
+    Apply scaled dot product attention to a sparse tensor.
+
+    Args:
+        q (SparseTensor): A [N, *, H, C] sparse tensor containing Qs.
+        kv (SparseTensor or torch.Tensor): A [N, *, 2, H, C] sparse tensor or a [N, L, 2, H, C] dense tensor containing Ks and Vs.
+    """
+    ...
+
+@overload
+def sparse_scaled_dot_product_attention(q: torch.Tensor, kv: SparseTensor) -> torch.Tensor:
+    """
+    Apply scaled dot product attention to a sparse tensor.
+
+    Args:
+        q (SparseTensor): A [N, L, H, C] dense tensor containing Qs.
+        kv (SparseTensor or torch.Tensor): A [N, *, 2, H, C] sparse tensor containing Ks and Vs.
+    """
+    ...
+
+@overload
+def sparse_scaled_dot_product_attention(q: SparseTensor, k: SparseTensor, v: SparseTensor) -> SparseTensor:
+    """
+    Apply scaled dot product attention to a sparse tensor.
+
+    Args:
+        q (SparseTensor): A [N, *, H, Ci] sparse tensor containing Qs.
+        k (SparseTensor): A [N, *, H, Ci] sparse tensor containing Ks.
+        v (SparseTensor): A [N, *, H, Co] sparse tensor containing Vs.
+
+    Note:
+        k and v are assumed to have the same coordinate map.
+    """
+    ...
+
+@overload
+def sparse_scaled_dot_product_attention(q: SparseTensor, k: torch.Tensor, v: torch.Tensor) -> SparseTensor:
+    """
+    Apply scaled dot product attention to a sparse tensor.
+
+    Args:
+        q (SparseTensor): A [N, *, H, Ci] sparse tensor containing Qs.
+        k (torch.Tensor): A [N, L, H, Ci] dense tensor containing Ks.
+        v (torch.Tensor): A [N, L, H, Co] dense tensor containing Vs.
+    """
+    ...
+
+@overload
+def sparse_scaled_dot_product_attention(q: torch.Tensor, k: SparseTensor, v: SparseTensor) -> torch.Tensor:
+    """
+    Apply scaled dot product attention to a sparse tensor.
+
+    Args:
+        q (torch.Tensor): A [N, L, H, Ci] dense tensor containing Qs.
+        k (SparseTensor): A [N, *, H, Ci] sparse tensor containing Ks.
+        v (SparseTensor): A [N, *, H, Co] sparse tensor containing Vs.
+    """
+    ...
+
+def sparse_scaled_dot_product_attention(*args, **kwargs):
+    arg_names_dict = {
+        1: ['qkv'],
+        2: ['q', 'kv'],
+        3: ['q', 'k', 'v']
+    }
+    num_all_args = len(args) + len(kwargs)
+    assert num_all_args in arg_names_dict, f"Invalid number of arguments, got {num_all_args}, expected 1, 2, or 3"
+    for key in arg_names_dict[num_all_args][len(args):]:
+        assert key in kwargs, f"Missing argument {key}"
+
+    if num_all_args == 1:
+        qkv = args[0] if len(args) > 0 else kwargs['qkv']
+        assert isinstance(qkv, SparseTensor), f"qkv must be a SparseTensor, got {type(qkv)}"
+        assert len(qkv.shape) == 4 and qkv.shape[1] == 3, f"Invalid shape for qkv, got {qkv.shape}, expected [N, *, 3, H, C]"
+        device = qkv.device
+
+        s = qkv
+        q_seqlen = [qkv.layout[i].stop - qkv.layout[i].start for i in range(qkv.shape[0])]
+        kv_seqlen = q_seqlen
+        qkv = qkv.feats     # [T, 3, H, C]
+
+    elif num_all_args == 2:
+        q = args[0] if len(args) > 0 else kwargs['q']
+        kv = args[1] if len(args) > 1 else kwargs['kv']
+        assert isinstance(q, SparseTensor) and isinstance(kv, (SparseTensor, torch.Tensor)) or \
+               isinstance(q, torch.Tensor) and isinstance(kv, SparseTensor), \
+               f"Invalid types, got {type(q)} and {type(kv)}"
+        assert q.shape[0] == kv.shape[0], f"Batch size mismatch, got {q.shape[0]} and {kv.shape[0]}"
+        device = q.device
+
+        if isinstance(q, SparseTensor):
+            assert len(q.shape) == 3, f"Invalid shape for q, got {q.shape}, expected [N, *, H, C]"
+            s = q
+            q_seqlen = [q.layout[i].stop - q.layout[i].start for i in range(q.shape[0])]
+            q = q.feats     # [T_Q, H, C]
+        else:
+            assert len(q.shape) == 4, f"Invalid shape for q, got {q.shape}, expected [N, L, H, C]"
+            s = None
+            N, L, H, C = q.shape
+            q_seqlen = [L] * N
+            q = q.reshape(N * L, H, C)   # [T_Q, H, C]
+
+        if isinstance(kv, SparseTensor):
+            assert len(kv.shape) == 4 and kv.shape[1] == 2, f"Invalid shape for kv, got {kv.shape}, expected [N, *, 2, H, C]"
+            kv_seqlen = [kv.layout[i].stop - kv.layout[i].start for i in range(kv.shape[0])]
+            kv = kv.feats     # [T_KV, 2, H, C]
+        else:
+            assert len(kv.shape) == 5, f"Invalid shape for kv, got {kv.shape}, expected [N, L, 2, H, C]"
+            N, L, _, H, C = kv.shape
+            kv_seqlen = [L] * N
+            kv = kv.reshape(N * L, 2, H, C)   # [T_KV, 2, H, C]
+
+    elif num_all_args == 3:
+        q = args[0] if len(args) > 0 else kwargs['q']
+        k = args[1] if len(args) > 1 else kwargs['k']
+        v = args[2] if len(args) > 2 else kwargs['v']
+        assert isinstance(q, SparseTensor) and isinstance(k, (SparseTensor, torch.Tensor)) and type(k) == type(v) or \
+               isinstance(q, torch.Tensor) and isinstance(k, SparseTensor) and isinstance(v, SparseTensor), \
+               f"Invalid types, got {type(q)}, {type(k)}, and {type(v)}"
+        assert q.shape[0] == k.shape[0] == v.shape[0], f"Batch size mismatch, got {q.shape[0]}, {k.shape[0]}, and {v.shape[0]}"
+        device = q.device
+
+        if isinstance(q, SparseTensor):
+            assert len(q.shape) == 3, f"Invalid shape for q, got {q.shape}, expected [N, *, H, Ci]"
+            s = q
+            q_seqlen = [q.layout[i].stop - q.layout[i].start for i in range(q.shape[0])]
+            q = q.feats     # [T_Q, H, Ci]
+        else:
+            assert len(q.shape) == 4, f"Invalid shape for q, got {q.shape}, expected [N, L, H, Ci]"
+            s = None
+            N, L, H, CI = q.shape
+            q_seqlen = [L] * N
+            q = q.reshape(N * L, H, CI)  # [T_Q, H, Ci]
+
+        if isinstance(k, SparseTensor):
+            assert len(k.shape) == 3, f"Invalid shape for k, got {k.shape}, expected [N, *, H, Ci]"
+            assert len(v.shape) == 3, f"Invalid shape for v, got {v.shape}, expected [N, *, H, Co]"
+            kv_seqlen = [k.layout[i].stop - k.layout[i].start for i in range(k.shape[0])]
+            k = k.feats     # [T_KV, H, Ci]
+            v = v.feats     # [T_KV, H, Co]
+        else:
+            assert len(k.shape) == 4, f"Invalid shape for k, got {k.shape}, expected [N, L, H, Ci]"
+            assert len(v.shape) == 4, f"Invalid shape for v, got {v.shape}, expected [N, L, H, Co]"
+            N, L, H, CI, CO = *k.shape, v.shape[-1]
+            kv_seqlen = [L] * N
+            k = k.reshape(N * L, H, CI)     # [T_KV, H, Ci]
+            v = v.reshape(N * L, H, CO)     # [T_KV, H, Co]
+
+    if DEBUG:
+        if s is not None:
+            for i in range(s.shape[0]):
+                assert (s.coords[s.layout[i]] == i).all(), f"SparseScaledDotProductSelfAttention: batch index mismatch"
+        if num_all_args in [2, 3]:
+            assert q.shape[:2] == [1, sum(q_seqlen)], f"SparseScaledDotProductSelfAttention: q shape mismatch"
+        if num_all_args == 3:
+            assert k.shape[:2] == [1, sum(kv_seqlen)], f"SparseScaledDotProductSelfAttention: k shape mismatch"
+            assert v.shape[:2] == [1, sum(kv_seqlen)], f"SparseScaledDotProductSelfAttention: v shape mismatch"
+
+    if ATTN == 'xformers':
+        if num_all_args == 1:
+            q, k, v = qkv.unbind(dim=1)
+        elif num_all_args == 2:
+            k, v = kv.unbind(dim=1)
+        q = q.unsqueeze(0)
+        k = k.unsqueeze(0)
+        v = v.unsqueeze(0)
+        mask = xops.fmha.BlockDiagonalMask.from_seqlens(q_seqlen, kv_seqlen)
+        out = xops.memory_efficient_attention(q, k, v, mask)[0]
+    elif ATTN == 'flash_attn':
+        cu_seqlens_q = torch.cat([torch.tensor([0]), torch.cumsum(torch.tensor(q_seqlen), dim=0)]).int().to(device)
+        if num_all_args in [2, 3]:
+            cu_seqlens_kv = torch.cat([torch.tensor([0]), torch.cumsum(torch.tensor(kv_seqlen), dim=0)]).int().to(device)
+        if num_all_args == 1:
+            out = flash_attn.flash_attn_varlen_qkvpacked_func(qkv, cu_seqlens_q, max(q_seqlen))
+        elif num_all_args == 2:
+            out = flash_attn.flash_attn_varlen_kvpacked_func(q, kv, cu_seqlens_q, cu_seqlens_kv, max(q_seqlen), max(kv_seqlen))
+        elif num_all_args == 3:
+            out = flash_attn.flash_attn_varlen_func(q, k, v, cu_seqlens_q, cu_seqlens_kv, max(q_seqlen), max(kv_seqlen))
+    else:
+        raise ValueError(f"Unknown attention module: {ATTN}")
+    
+    if s is not None:
+        return s.replace(out)
+    else:
+        return out.reshape(N, L, H, -1)

Stable3DGen/hi3dgen/modules/sparse/attention/modules.py

@@ -0,0 +1,163 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+import torch
+import torch.nn as nn
+import torch.nn.functional as F
+from .. import SparseTensor
+from .full_attn import sparse_scaled_dot_product_attention
+from .serialized_attn import SerializeMode, sparse_serialized_scaled_dot_product_self_attention
+from .windowed_attn import sparse_windowed_scaled_dot_product_self_attention
+from ...attention import RotaryPositionEmbedder
+
+
+class SparseMultiHeadRMSNorm(nn.Module):
+    def __init__(self, dim: int, heads: int):
+        super().__init__()
+        self.scale = dim ** 0.5
+        self.gamma = nn.Parameter(torch.ones(heads, dim))
+
+    def forward(self, x: Union[SparseTensor, torch.Tensor]) -> Union[SparseTensor, torch.Tensor]:
+        x_type = x.dtype
+        x = x.float()
+        if isinstance(x, SparseTensor):
+            x = x.replace(F.normalize(x.feats, dim=-1))
+        else:
+            x = F.normalize(x, dim=-1)            
+        return (x * self.gamma * self.scale).to(x_type)
+
+
+class SparseMultiHeadAttention(nn.Module):
+    def __init__(
+        self,
+        channels: int,
+        num_heads: int,
+        ctx_channels: Optional[int] = None,
+        type: Literal["self", "cross"] = "self",
+        attn_mode: Literal["full", "serialized", "windowed"] = "full",
+        window_size: Optional[int] = None,
+        shift_sequence: Optional[int] = None,
+        shift_window: Optional[Tuple[int, int, int]] = None,
+        serialize_mode: Optional[SerializeMode] = None,
+        qkv_bias: bool = True,
+        use_rope: bool = False,
+        qk_rms_norm: bool = False,
+    ):
+        super().__init__()
+        assert channels % num_heads == 0
+        assert type in ["self", "cross"], f"Invalid attention type: {type}"
+        assert attn_mode in ["full", "serialized", "windowed"], f"Invalid attention mode: {attn_mode}"
+        assert type == "self" or attn_mode == "full", "Cross-attention only supports full attention"
+        assert type == "self" or use_rope is False, "Rotary position embeddings only supported for self-attention"
+        self.channels = channels
+        self.ctx_channels = ctx_channels if ctx_channels is not None else channels
+        self.num_heads = num_heads
+        self._type = type
+        self.attn_mode = attn_mode
+        self.window_size = window_size
+        self.shift_sequence = shift_sequence
+        self.shift_window = shift_window
+        self.serialize_mode = serialize_mode
+        self.use_rope = use_rope
+        self.qk_rms_norm = qk_rms_norm
+
+        if self._type == "self":
+            self.to_qkv = nn.Linear(channels, channels * 3, bias=qkv_bias)
+        else:
+            self.to_q = nn.Linear(channels, channels, bias=qkv_bias)
+            self.to_kv = nn.Linear(self.ctx_channels, channels * 2, bias=qkv_bias)
+        
+        if self.qk_rms_norm:
+            self.q_rms_norm = SparseMultiHeadRMSNorm(channels // num_heads, num_heads)
+            self.k_rms_norm = SparseMultiHeadRMSNorm(channels // num_heads, num_heads)
+            
+        self.to_out = nn.Linear(channels, channels)
+
+        if use_rope:
+            self.rope = RotaryPositionEmbedder(channels)
+
+    @staticmethod
+    def _linear(module: nn.Linear, x: Union[SparseTensor, torch.Tensor]) -> Union[SparseTensor, torch.Tensor]:
+        if isinstance(x, SparseTensor):
+            return x.replace(module(x.feats))
+        else:
+            return module(x)
+
+    @staticmethod
+    def _reshape_chs(x: Union[SparseTensor, torch.Tensor], shape: Tuple[int, ...]) -> Union[SparseTensor, torch.Tensor]:
+        if isinstance(x, SparseTensor):
+            return x.reshape(*shape)
+        else:
+            return x.reshape(*x.shape[:2], *shape)
+
+    def _fused_pre(self, x: Union[SparseTensor, torch.Tensor], num_fused: int) -> Union[SparseTensor, torch.Tensor]:
+        if isinstance(x, SparseTensor):
+            x_feats = x.feats.unsqueeze(0)
+        else:
+            x_feats = x
+        x_feats = x_feats.reshape(*x_feats.shape[:2], num_fused, self.num_heads, -1)
+        return x.replace(x_feats.squeeze(0)) if isinstance(x, SparseTensor) else x_feats
+
+    def _rope(self, qkv: SparseTensor) -> SparseTensor:
+        q, k, v = qkv.feats.unbind(dim=1)   # [T, H, C]
+        q, k = self.rope(q, k, qkv.coords[:, 1:])
+        qkv = qkv.replace(torch.stack([q, k, v], dim=1)) 
+        return qkv
+    
+    def forward(self, x: Union[SparseTensor, torch.Tensor], context: Optional[Union[SparseTensor, torch.Tensor]] = None) -> Union[SparseTensor, torch.Tensor]:
+        if self._type == "self":
+            qkv = self._linear(self.to_qkv, x)
+            qkv = self._fused_pre(qkv, num_fused=3)
+            if self.use_rope:
+                qkv = self._rope(qkv)
+            if self.qk_rms_norm:
+                q, k, v = qkv.unbind(dim=1)
+                q = self.q_rms_norm(q)
+                k = self.k_rms_norm(k)
+                qkv = qkv.replace(torch.stack([q.feats, k.feats, v.feats], dim=1))
+            if self.attn_mode == "full":
+                h = sparse_scaled_dot_product_attention(qkv)
+            elif self.attn_mode == "serialized":
+                h = sparse_serialized_scaled_dot_product_self_attention(
+                    qkv, self.window_size, serialize_mode=self.serialize_mode, shift_sequence=self.shift_sequence, shift_window=self.shift_window
+                )
+            elif self.attn_mode == "windowed":
+                h = sparse_windowed_scaled_dot_product_self_attention(
+                    qkv, self.window_size, shift_window=self.shift_window
+                )
+        else:
+            q = self._linear(self.to_q, x)
+            q = self._reshape_chs(q, (self.num_heads, -1))
+            kv = self._linear(self.to_kv, context)
+            kv = self._fused_pre(kv, num_fused=2)
+            if self.qk_rms_norm:
+                q = self.q_rms_norm(q)
+                k, v = kv.unbind(dim=1)
+                k = self.k_rms_norm(k)
+                kv = kv.replace(torch.stack([k.feats, v.feats], dim=1))
+            h = sparse_scaled_dot_product_attention(q, kv)
+        h = self._reshape_chs(h, (-1,))
+        h = self._linear(self.to_out, h)
+        return h

Stable3DGen/hi3dgen/modules/sparse/attention/serialized_attn.py

@@ -0,0 +1,217 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+from enum import Enum
+import torch
+import math
+from .. import SparseTensor
+from .. import DEBUG, ATTN
+
+if ATTN == 'xformers':
+    import xformers.ops as xops
+elif ATTN == 'flash_attn':
+    import flash_attn
+else:
+    raise ValueError(f"Unknown attention module: {ATTN}")
+
+
+__all__ = [
+    'sparse_serialized_scaled_dot_product_self_attention',
+]
+
+
+class SerializeMode(Enum):
+    Z_ORDER = 0
+    Z_ORDER_TRANSPOSED = 1
+    HILBERT = 2
+    HILBERT_TRANSPOSED = 3
+
+
+SerializeModes = [
+    SerializeMode.Z_ORDER,
+    SerializeMode.Z_ORDER_TRANSPOSED,
+    SerializeMode.HILBERT,
+    SerializeMode.HILBERT_TRANSPOSED
+]
+
+
+def calc_serialization(
+    tensor: SparseTensor,
+    window_size: int,
+    serialize_mode: SerializeMode = SerializeMode.Z_ORDER,
+    shift_sequence: int = 0,
+    shift_window: Tuple[int, int, int] = (0, 0, 0)
+) -> Tuple[torch.Tensor, torch.Tensor, List[int]]:
+    """
+    Calculate serialization and partitioning for a set of coordinates.
+
+    Args:
+        tensor (SparseTensor): The input tensor.
+        window_size (int): The window size to use.
+        serialize_mode (SerializeMode): The serialization mode to use.
+        shift_sequence (int): The shift of serialized sequence.
+        shift_window (Tuple[int, int, int]): The shift of serialized coordinates.
+
+    Returns:
+        (torch.Tensor, torch.Tensor): Forwards and backwards indices.
+    """
+    fwd_indices = []
+    bwd_indices = []
+    seq_lens = []
+    seq_batch_indices = []
+    offsets = [0]
+    
+    if 'vox2seq' not in globals():
+        import vox2seq
+
+    # Serialize the input
+    serialize_coords = tensor.coords[:, 1:].clone()
+    serialize_coords += torch.tensor(shift_window, dtype=torch.int32, device=tensor.device).reshape(1, 3)
+    if serialize_mode == SerializeMode.Z_ORDER:
+        code = vox2seq.encode(serialize_coords, mode='z_order', permute=[0, 1, 2])
+    elif serialize_mode == SerializeMode.Z_ORDER_TRANSPOSED:
+        code = vox2seq.encode(serialize_coords, mode='z_order', permute=[1, 0, 2])
+    elif serialize_mode == SerializeMode.HILBERT:
+        code = vox2seq.encode(serialize_coords, mode='hilbert', permute=[0, 1, 2])
+    elif serialize_mode == SerializeMode.HILBERT_TRANSPOSED:
+        code = vox2seq.encode(serialize_coords, mode='hilbert', permute=[1, 0, 2])
+    else:
+        raise ValueError(f"Unknown serialize mode: {serialize_mode}")
+    
+    for bi, s in enumerate(tensor.layout):
+        num_points = s.stop - s.start
+        num_windows = (num_points + window_size - 1) // window_size
+        valid_window_size = num_points / num_windows
+        to_ordered = torch.argsort(code[s.start:s.stop])
+        if num_windows == 1:
+            fwd_indices.append(to_ordered)
+            bwd_indices.append(torch.zeros_like(to_ordered).scatter_(0, to_ordered, torch.arange(num_points, device=tensor.device)))
+            fwd_indices[-1] += s.start
+            bwd_indices[-1] += offsets[-1]
+            seq_lens.append(num_points)
+            seq_batch_indices.append(bi)
+            offsets.append(offsets[-1] + seq_lens[-1])
+        else:
+            # Partition the input
+            offset = 0
+            mids = [(i + 0.5) * valid_window_size + shift_sequence for i in range(num_windows)]
+            split = [math.floor(i * valid_window_size + shift_sequence) for i in range(num_windows + 1)]
+            bwd_index = torch.zeros((num_points,), dtype=torch.int64, device=tensor.device)
+            for i in range(num_windows):
+                mid = mids[i]
+                valid_start = split[i]
+                valid_end = split[i + 1]
+                padded_start = math.floor(mid - 0.5 * window_size)
+                padded_end = padded_start + window_size
+                fwd_indices.append(to_ordered[torch.arange(padded_start, padded_end, device=tensor.device) % num_points])
+                offset += valid_start - padded_start
+                bwd_index.scatter_(0, fwd_indices[-1][valid_start-padded_start:valid_end-padded_start], torch.arange(offset, offset + valid_end - valid_start, device=tensor.device))
+                offset += padded_end - valid_start
+                fwd_indices[-1] += s.start
+            seq_lens.extend([window_size] * num_windows)
+            seq_batch_indices.extend([bi] * num_windows)
+            bwd_indices.append(bwd_index + offsets[-1])
+            offsets.append(offsets[-1] + num_windows * window_size)
+
+    fwd_indices = torch.cat(fwd_indices)
+    bwd_indices = torch.cat(bwd_indices)
+
+    return fwd_indices, bwd_indices, seq_lens, seq_batch_indices
+    
+
+def sparse_serialized_scaled_dot_product_self_attention(
+    qkv: SparseTensor,
+    window_size: int,
+    serialize_mode: SerializeMode = SerializeMode.Z_ORDER,
+    shift_sequence: int = 0,
+    shift_window: Tuple[int, int, int] = (0, 0, 0)
+) -> SparseTensor:
+    """
+    Apply serialized scaled dot product self attention to a sparse tensor.
+
+    Args:
+        qkv (SparseTensor): [N, *, 3, H, C] sparse tensor containing Qs, Ks, and Vs.
+        window_size (int): The window size to use.
+        serialize_mode (SerializeMode): The serialization mode to use.
+        shift_sequence (int): The shift of serialized sequence.
+        shift_window (Tuple[int, int, int]): The shift of serialized coordinates.
+        shift (int): The shift to use.
+    """
+    assert len(qkv.shape) == 4 and qkv.shape[1] == 3, f"Invalid shape for qkv, got {qkv.shape}, expected [N, *, 3, H, C]"
+
+    serialization_spatial_cache_name = f'serialization_{serialize_mode}_{window_size}_{shift_sequence}_{shift_window}'
+    serialization_spatial_cache = qkv.get_spatial_cache(serialization_spatial_cache_name)
+    if serialization_spatial_cache is None:
+        fwd_indices, bwd_indices, seq_lens, seq_batch_indices = calc_serialization(qkv, window_size, serialize_mode, shift_sequence, shift_window)
+        qkv.register_spatial_cache(serialization_spatial_cache_name, (fwd_indices, bwd_indices, seq_lens, seq_batch_indices))
+    else:
+        fwd_indices, bwd_indices, seq_lens, seq_batch_indices = serialization_spatial_cache
+
+    M = fwd_indices.shape[0]
+    T = qkv.feats.shape[0]
+    H = qkv.feats.shape[2]
+    C = qkv.feats.shape[3]
+    
+    qkv_feats = qkv.feats[fwd_indices]      # [M, 3, H, C]
+
+    if DEBUG:
+        start = 0
+        qkv_coords = qkv.coords[fwd_indices]
+        for i in range(len(seq_lens)):
+            assert (qkv_coords[start:start+seq_lens[i], 0] == seq_batch_indices[i]).all(), f"SparseWindowedScaledDotProductSelfAttention: batch index mismatch"
+            start += seq_lens[i]
+
+    if all([seq_len == window_size for seq_len in seq_lens]):
+        B = len(seq_lens)
+        N = window_size
+        qkv_feats = qkv_feats.reshape(B, N, 3, H, C)
+        if ATTN == 'xformers':
+            q, k, v = qkv_feats.unbind(dim=2)                       # [B, N, H, C]
+            out = xops.memory_efficient_attention(q, k, v)          # [B, N, H, C]
+        elif ATTN == 'flash_attn':
+            out = flash_attn.flash_attn_qkvpacked_func(qkv_feats)   # [B, N, H, C]
+        else:
+            raise ValueError(f"Unknown attention module: {ATTN}")
+        out = out.reshape(B * N, H, C)                              # [M, H, C]
+    else:
+        if ATTN == 'xformers':
+            q, k, v = qkv_feats.unbind(dim=1)                       # [M, H, C]
+            q = q.unsqueeze(0)                                      # [1, M, H, C]
+            k = k.unsqueeze(0)                                      # [1, M, H, C]
+            v = v.unsqueeze(0)                                      # [1, M, H, C]
+            mask = xops.fmha.BlockDiagonalMask.from_seqlens(seq_lens)
+            out = xops.memory_efficient_attention(q, k, v, mask)[0] # [M, H, C]
+        elif ATTN == 'flash_attn':
+            cu_seqlens = torch.cat([torch.tensor([0]), torch.cumsum(torch.tensor(seq_lens), dim=0)], dim=0) \
+                        .to(qkv.device).int()
+            out = flash_attn.flash_attn_varlen_qkvpacked_func(qkv_feats, cu_seqlens, max(seq_lens)) # [M, H, C]
+
+    out = out[bwd_indices]      # [T, H, C]
+
+    if DEBUG:
+        qkv_coords = qkv_coords[bwd_indices]
+        assert torch.equal(qkv_coords, qkv.coords), "SparseWindowedScaledDotProductSelfAttention: coordinate mismatch"
+
+    return qkv.replace(out)

Stable3DGen/hi3dgen/modules/sparse/attention/windowed_attn.py

@@ -0,0 +1,159 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+import torch
+import math
+from .. import SparseTensor
+from .. import DEBUG, ATTN
+
+if ATTN == 'xformers':
+    import xformers.ops as xops
+elif ATTN == 'flash_attn':
+    import flash_attn
+else:
+    raise ValueError(f"Unknown attention module: {ATTN}")
+
+
+__all__ = [
+    'sparse_windowed_scaled_dot_product_self_attention',
+]
+
+
+def calc_window_partition(
+    tensor: SparseTensor,
+    window_size: Union[int, Tuple[int, ...]],
+    shift_window: Union[int, Tuple[int, ...]] = 0
+) -> Tuple[torch.Tensor, torch.Tensor, List[int], List[int]]:
+    """
+    Calculate serialization and partitioning for a set of coordinates.
+
+    Args:
+        tensor (SparseTensor): The input tensor.
+        window_size (int): The window size to use.
+        shift_window (Tuple[int, ...]): The shift of serialized coordinates.
+
+    Returns:
+        (torch.Tensor): Forwards indices.
+        (torch.Tensor): Backwards indices.
+        (List[int]): Sequence lengths.
+        (List[int]): Sequence batch indices.
+    """
+    DIM = tensor.coords.shape[1] - 1
+    shift_window = (shift_window,) * DIM if isinstance(shift_window, int) else shift_window
+    window_size = (window_size,) * DIM if isinstance(window_size, int) else window_size
+    shifted_coords = tensor.coords.clone().detach()
+    shifted_coords[:, 1:] += torch.tensor(shift_window, device=tensor.device, dtype=torch.int32).unsqueeze(0)
+
+    MAX_COORDS = shifted_coords[:, 1:].max(dim=0).values.tolist()
+    NUM_WINDOWS = [math.ceil((mc + 1) / ws) for mc, ws in zip(MAX_COORDS, window_size)]
+    OFFSET = torch.cumprod(torch.tensor([1] + NUM_WINDOWS[::-1]), dim=0).tolist()[::-1]
+
+    shifted_coords[:, 1:] //= torch.tensor(window_size, device=tensor.device, dtype=torch.int32).unsqueeze(0)
+    shifted_indices = (shifted_coords * torch.tensor(OFFSET, device=tensor.device, dtype=torch.int32).unsqueeze(0)).sum(dim=1)
+    fwd_indices = torch.argsort(shifted_indices)
+    bwd_indices = torch.empty_like(fwd_indices)
+    bwd_indices[fwd_indices] = torch.arange(fwd_indices.shape[0], device=tensor.device)
+    seq_lens = torch.bincount(shifted_indices)
+    seq_batch_indices = torch.arange(seq_lens.shape[0], device=tensor.device, dtype=torch.int32) // OFFSET[0]
+    mask = seq_lens != 0
+    seq_lens = seq_lens[mask].tolist()
+    seq_batch_indices = seq_batch_indices[mask].tolist()
+
+    return fwd_indices, bwd_indices, seq_lens, seq_batch_indices
+    
+
+def sparse_windowed_scaled_dot_product_self_attention(
+    qkv: SparseTensor,
+    window_size: int,
+    shift_window: Tuple[int, int, int] = (0, 0, 0)
+) -> SparseTensor:
+    """
+    Apply windowed scaled dot product self attention to a sparse tensor.
+
+    Args:
+        qkv (SparseTensor): [N, *, 3, H, C] sparse tensor containing Qs, Ks, and Vs.
+        window_size (int): The window size to use.
+        shift_window (Tuple[int, int, int]): The shift of serialized coordinates.
+        shift (int): The shift to use.
+    """
+    assert len(qkv.shape) == 4 and qkv.shape[1] == 3, f"Invalid shape for qkv, got {qkv.shape}, expected [N, *, 3, H, C]"
+
+    serialization_spatial_cache_name = f'window_partition_{window_size}_{shift_window}'
+    serialization_spatial_cache = qkv.get_spatial_cache(serialization_spatial_cache_name)
+    if serialization_spatial_cache is None:
+        fwd_indices, bwd_indices, seq_lens, seq_batch_indices = calc_window_partition(qkv, window_size, shift_window)
+        qkv.register_spatial_cache(serialization_spatial_cache_name, (fwd_indices, bwd_indices, seq_lens, seq_batch_indices))
+    else:
+        fwd_indices, bwd_indices, seq_lens, seq_batch_indices = serialization_spatial_cache
+
+    M = fwd_indices.shape[0]
+    T = qkv.feats.shape[0]
+    H = qkv.feats.shape[2]
+    C = qkv.feats.shape[3]
+    
+    qkv_feats = qkv.feats[fwd_indices]      # [M, 3, H, C]
+
+    if DEBUG:
+        start = 0
+        qkv_coords = qkv.coords[fwd_indices]
+        for i in range(len(seq_lens)):
+            seq_coords = qkv_coords[start:start+seq_lens[i]]
+            assert (seq_coords[:, 0] == seq_batch_indices[i]).all(), f"SparseWindowedScaledDotProductSelfAttention: batch index mismatch"
+            assert (seq_coords[:, 1:].max(dim=0).values - seq_coords[:, 1:].min(dim=0).values < window_size).all(), \
+                    f"SparseWindowedScaledDotProductSelfAttention: window size exceeded"
+            start += seq_lens[i]
+
+    if all([seq_len == window_size for seq_len in seq_lens]):
+        B = len(seq_lens)
+        N = window_size
+        qkv_feats = qkv_feats.reshape(B, N, 3, H, C)
+        if ATTN == 'xformers':
+            q, k, v = qkv_feats.unbind(dim=2)                       # [B, N, H, C]
+            out = xops.memory_efficient_attention(q, k, v)          # [B, N, H, C]
+        elif ATTN == 'flash_attn':
+            out = flash_attn.flash_attn_qkvpacked_func(qkv_feats)   # [B, N, H, C]
+        else:
+            raise ValueError(f"Unknown attention module: {ATTN}")
+        out = out.reshape(B * N, H, C)                              # [M, H, C]
+    else:
+        if ATTN == 'xformers':
+            q, k, v = qkv_feats.unbind(dim=1)                       # [M, H, C]
+            q = q.unsqueeze(0)                                      # [1, M, H, C]
+            k = k.unsqueeze(0)                                      # [1, M, H, C]
+            v = v.unsqueeze(0)                                      # [1, M, H, C]
+            mask = xops.fmha.BlockDiagonalMask.from_seqlens(seq_lens)
+            out = xops.memory_efficient_attention(q, k, v, mask)[0] # [M, H, C]
+        elif ATTN == 'flash_attn':
+            cu_seqlens = torch.cat([torch.tensor([0]), torch.cumsum(torch.tensor(seq_lens), dim=0)], dim=0) \
+                        .to(qkv.device).int()
+            out = flash_attn.flash_attn_varlen_qkvpacked_func(qkv_feats, cu_seqlens, max(seq_lens)) # [M, H, C]
+
+    out = out[bwd_indices]      # [T, H, C]
+
+    if DEBUG:
+        qkv_coords = qkv_coords[bwd_indices]
+        assert torch.equal(qkv_coords, qkv.coords), "SparseWindowedScaledDotProductSelfAttention: coordinate mismatch"
+
+    return qkv.replace(out)

Stable3DGen/hi3dgen/modules/sparse/basic.py

@@ -0,0 +1,483 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from typing import *
+import torch
+import torch.nn as nn
+from . import BACKEND, DEBUG
+SparseTensorData = None # Lazy import
+
+
+__all__ = [
+    'SparseTensor',
+    'sparse_batch_broadcast',
+    'sparse_batch_op',
+    'sparse_cat',
+    'sparse_unbind',
+]
+
+
+class SparseTensor:
+    """
+    Sparse tensor with support for both torchsparse and spconv backends.
+    
+    Parameters:
+    - feats (torch.Tensor): Features of the sparse tensor.
+    - coords (torch.Tensor): Coordinates of the sparse tensor.
+    - shape (torch.Size): Shape of the sparse tensor.
+    - layout (List[slice]): Layout of the sparse tensor for each batch
+    - data (SparseTensorData): Sparse tensor data used for convolusion
+
+    NOTE:
+    - Data corresponding to a same batch should be contiguous.
+    - Coords should be in [0, 1023]
+    """
+    @overload
+    def __init__(self, feats: torch.Tensor, coords: torch.Tensor, shape: Optional[torch.Size] = None, layout: Optional[List[slice]] = None, **kwargs): ...
+
+    @overload
+    def __init__(self, data, shape: Optional[torch.Size] = None, layout: Optional[List[slice]] = None, **kwargs): ...
+
+    def __init__(self, *args, **kwargs):
+        # Lazy import of sparse tensor backend
+        global SparseTensorData
+        if SparseTensorData is None:
+            import importlib
+            if BACKEND == 'torchsparse':
+                SparseTensorData = importlib.import_module('torchsparse').SparseTensor
+            elif BACKEND == 'spconv':
+                SparseTensorData = importlib.import_module('spconv.pytorch').SparseConvTensor
+                
+        method_id = 0
+        if len(args) != 0:
+            method_id = 0 if isinstance(args[0], torch.Tensor) else 1
+        else:
+            method_id = 1 if 'data' in kwargs else 0
+
+        if method_id == 0:
+            feats, coords, shape, layout = args + (None,) * (4 - len(args))
+            if 'feats' in kwargs:
+                feats = kwargs['feats']
+                del kwargs['feats']
+            if 'coords' in kwargs:
+                coords = kwargs['coords']
+                del kwargs['coords']
+            if 'shape' in kwargs:
+                shape = kwargs['shape']
+                del kwargs['shape']
+            if 'layout' in kwargs:
+                layout = kwargs['layout']
+                del kwargs['layout']
+
+            if shape is None:
+                shape = self.__cal_shape(feats, coords)
+            if layout is None:
+                layout = self.__cal_layout(coords, shape[0])
+            if BACKEND == 'torchsparse':
+                self.data = SparseTensorData(feats, coords, **kwargs)
+            elif BACKEND == 'spconv':
+                spatial_shape = list(coords.max(0)[0] + 1)[1:]
+                self.data = SparseTensorData(feats.reshape(feats.shape[0], -1), coords, spatial_shape, shape[0], **kwargs)
+                self.data._features = feats
+        elif method_id == 1:
+            data, shape, layout = args + (None,) * (3 - len(args))
+            if 'data' in kwargs:
+                data = kwargs['data']
+                del kwargs['data']
+            if 'shape' in kwargs:
+                shape = kwargs['shape']
+                del kwargs['shape']
+            if 'layout' in kwargs:
+                layout = kwargs['layout']
+                del kwargs['layout']
+
+            self.data = data
+            if shape is None:
+                shape = self.__cal_shape(self.feats, self.coords)
+            if layout is None:
+                layout = self.__cal_layout(self.coords, shape[0])
+
+        self._shape = shape
+        self._layout = layout
+        self._scale = kwargs.get('scale', (1, 1, 1))
+        self._spatial_cache = kwargs.get('spatial_cache', {})
+
+        if DEBUG:
+            try:
+                assert self.feats.shape[0] == self.coords.shape[0], f"Invalid feats shape: {self.feats.shape}, coords shape: {self.coords.shape}"
+                assert self.shape == self.__cal_shape(self.feats, self.coords), f"Invalid shape: {self.shape}"
+                assert self.layout == self.__cal_layout(self.coords, self.shape[0]), f"Invalid layout: {self.layout}"
+                for i in range(self.shape[0]):
+                    assert torch.all(self.coords[self.layout[i], 0] == i), f"The data of batch {i} is not contiguous"
+            except Exception as e:
+                print('Debugging information:')
+                print(f"- Shape: {self.shape}")
+                print(f"- Layout: {self.layout}")
+                print(f"- Scale: {self._scale}")
+                print(f"- Coords: {self.coords}")
+                raise e
+        
+    def __cal_shape(self, feats, coords):
+        shape = []
+        shape.append(coords[:, 0].max().item() + 1)
+        shape.extend([*feats.shape[1:]])
+        return torch.Size(shape)
+    
+    def __cal_layout(self, coords, batch_size):
+        seq_len = torch.bincount(coords[:, 0], minlength=batch_size)
+        offset = torch.cumsum(seq_len, dim=0) 
+        layout = [slice((offset[i] - seq_len[i]).item(), offset[i].item()) for i in range(batch_size)]
+        return layout
+    
+    @property
+    def shape(self) -> torch.Size:
+        return self._shape
+    
+    def dim(self) -> int:
+        return len(self.shape)
+    
+    @property
+    def layout(self) -> List[slice]:
+        return self._layout
+
+    @property
+    def feats(self) -> torch.Tensor:
+        if BACKEND == 'torchsparse':
+            return self.data.F
+        elif BACKEND == 'spconv':
+            return self.data.features
+    
+    @feats.setter
+    def feats(self, value: torch.Tensor):
+        if BACKEND == 'torchsparse':
+            self.data.F = value
+        elif BACKEND == 'spconv':
+            self.data.features = value
+
+    @property
+    def coords(self) -> torch.Tensor:
+        if BACKEND == 'torchsparse':
+            return self.data.C
+        elif BACKEND == 'spconv':
+            return self.data.indices
+        
+    @coords.setter
+    def coords(self, value: torch.Tensor):
+        if BACKEND == 'torchsparse':
+            self.data.C = value
+        elif BACKEND == 'spconv':
+            self.data.indices = value
+
+    @property
+    def dtype(self):
+        return self.feats.dtype
+
+    @property
+    def device(self):
+        return self.feats.device
+
+    @overload
+    def to(self, dtype: torch.dtype) -> 'SparseTensor': ...
+
+    @overload
+    def to(self, device: Optional[Union[str, torch.device]] = None, dtype: Optional[torch.dtype] = None) -> 'SparseTensor': ...
+
+    def to(self, *args, **kwargs) -> 'SparseTensor':
+        device = None
+        dtype = None
+        if len(args) == 2:
+            device, dtype = args
+        elif len(args) == 1:
+            if isinstance(args[0], torch.dtype):
+                dtype = args[0]
+            else:
+                device = args[0]
+        if 'dtype' in kwargs:
+            assert dtype is None, "to() received multiple values for argument 'dtype'"
+            dtype = kwargs['dtype']
+        if 'device' in kwargs:
+            assert device is None, "to() received multiple values for argument 'device'"
+            device = kwargs['device']
+        
+        new_feats = self.feats.to(device=device, dtype=dtype)
+        new_coords = self.coords.to(device=device)
+        return self.replace(new_feats, new_coords)
+
+    def type(self, dtype):
+        new_feats = self.feats.type(dtype)
+        return self.replace(new_feats)
+
+    def cpu(self) -> 'SparseTensor':
+        new_feats = self.feats.cpu()
+        new_coords = self.coords.cpu()
+        return self.replace(new_feats, new_coords)
+    
+    def cuda(self) -> 'SparseTensor':
+        new_feats = self.feats.cuda()
+        new_coords = self.coords.cuda()
+        return self.replace(new_feats, new_coords)
+
+    def half(self) -> 'SparseTensor':
+        new_feats = self.feats.half()
+        return self.replace(new_feats)
+    
+    def float(self) -> 'SparseTensor':
+        new_feats = self.feats.float()
+        return self.replace(new_feats)
+    
+    def detach(self) -> 'SparseTensor':
+        new_coords = self.coords.detach()
+        new_feats = self.feats.detach()
+        return self.replace(new_feats, new_coords)
+
+    def dense(self) -> torch.Tensor:
+        if BACKEND == 'torchsparse':
+            return self.data.dense()
+        elif BACKEND == 'spconv':
+            return self.data.dense()
+
+    def reshape(self, *shape) -> 'SparseTensor':
+        new_feats = self.feats.reshape(self.feats.shape[0], *shape)
+        return self.replace(new_feats)
+    
+    def unbind(self, dim: int) -> List['SparseTensor']:
+        return sparse_unbind(self, dim)
+
+    def replace(self, feats: torch.Tensor, coords: Optional[torch.Tensor] = None) -> 'SparseTensor':
+        new_shape = [self.shape[0]]
+        new_shape.extend(feats.shape[1:])
+        if BACKEND == 'torchsparse':
+            new_data = SparseTensorData(
+                feats=feats,
+                coords=self.data.coords if coords is None else coords,
+                stride=self.data.stride,
+                spatial_range=self.data.spatial_range,
+            )
+            new_data._caches = self.data._caches
+        elif BACKEND == 'spconv':
+            new_data = SparseTensorData(
+                self.data.features.reshape(self.data.features.shape[0], -1),
+                self.data.indices,
+                self.data.spatial_shape,
+                self.data.batch_size,
+                self.data.grid,
+                self.data.voxel_num,
+                self.data.indice_dict
+            )
+            new_data._features = feats
+            new_data.benchmark = self.data.benchmark
+            new_data.benchmark_record = self.data.benchmark_record
+            new_data.thrust_allocator = self.data.thrust_allocator
+            new_data._timer = self.data._timer
+            new_data.force_algo = self.data.force_algo
+            new_data.int8_scale = self.data.int8_scale
+            if coords is not None:
+                new_data.indices = coords
+        new_tensor = SparseTensor(new_data, shape=torch.Size(new_shape), layout=self.layout, scale=self._scale, spatial_cache=self._spatial_cache)
+        return new_tensor
+
+    @staticmethod
+    def full(aabb, dim, value, dtype=torch.float32, device=None) -> 'SparseTensor':
+        N, C = dim
+        x = torch.arange(aabb[0], aabb[3] + 1)
+        y = torch.arange(aabb[1], aabb[4] + 1)
+        z = torch.arange(aabb[2], aabb[5] + 1)
+        coords = torch.stack(torch.meshgrid(x, y, z, indexing='ij'), dim=-1).reshape(-1, 3)
+        coords = torch.cat([
+            torch.arange(N).view(-1, 1).repeat(1, coords.shape[0]).view(-1, 1),
+            coords.repeat(N, 1),
+        ], dim=1).to(dtype=torch.int32, device=device)
+        feats = torch.full((coords.shape[0], C), value, dtype=dtype, device=device)
+        return SparseTensor(feats=feats, coords=coords)
+
+    def __merge_sparse_cache(self, other: 'SparseTensor') -> dict:
+        new_cache = {}
+        for k in set(list(self._spatial_cache.keys()) + list(other._spatial_cache.keys())):
+            if k in self._spatial_cache:
+                new_cache[k] = self._spatial_cache[k]
+            if k in other._spatial_cache:
+                if k not in new_cache:
+                    new_cache[k] = other._spatial_cache[k]
+                else:
+                    new_cache[k].update(other._spatial_cache[k])
+        return new_cache
+
+    def __neg__(self) -> 'SparseTensor':
+        return self.replace(-self.feats)
+    
+    def __elemwise__(self, other: Union[torch.Tensor, 'SparseTensor'], op: callable) -> 'SparseTensor':
+        if isinstance(other, torch.Tensor):
+            try:
+                other = torch.broadcast_to(other, self.shape)
+                other = sparse_batch_broadcast(self, other)
+            except:
+                pass
+        if isinstance(other, SparseTensor):
+            other = other.feats
+        new_feats = op(self.feats, other)
+        new_tensor = self.replace(new_feats)
+        if isinstance(other, SparseTensor):
+            new_tensor._spatial_cache = self.__merge_sparse_cache(other)
+        return new_tensor
+
+    def __add__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, torch.add)
+
+    def __radd__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, torch.add)
+    
+    def __sub__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, torch.sub)
+    
+    def __rsub__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, lambda x, y: torch.sub(y, x))
+
+    def __mul__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, torch.mul)
+
+    def __rmul__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, torch.mul)
+
+    def __truediv__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, torch.div)
+
+    def __rtruediv__(self, other: Union[torch.Tensor, 'SparseTensor', float]) -> 'SparseTensor':
+        return self.__elemwise__(other, lambda x, y: torch.div(y, x))
+
+    def __getitem__(self, idx):
+        if isinstance(idx, int):
+            idx = [idx]
+        elif isinstance(idx, slice):
+            idx = range(*idx.indices(self.shape[0]))
+        elif isinstance(idx, torch.Tensor):
+            if idx.dtype == torch.bool:
+                assert idx.shape == (self.shape[0],), f"Invalid index shape: {idx.shape}"
+                idx = idx.nonzero().squeeze(1)
+            elif idx.dtype in [torch.int32, torch.int64]:
+                assert len(idx.shape) == 1, f"Invalid index shape: {idx.shape}"
+            else:
+                raise ValueError(f"Unknown index type: {idx.dtype}")
+        else:
+            raise ValueError(f"Unknown index type: {type(idx)}")
+        
+        coords = []
+        feats = []
+        for new_idx, old_idx in enumerate(idx):
+            coords.append(self.coords[self.layout[old_idx]].clone())
+            coords[-1][:, 0] = new_idx
+            feats.append(self.feats[self.layout[old_idx]])
+        coords = torch.cat(coords, dim=0).contiguous()
+        feats = torch.cat(feats, dim=0).contiguous()
+        return SparseTensor(feats=feats, coords=coords)
+
+    def register_spatial_cache(self, key, value) -> None:
+        """
+        Register a spatial cache.
+        The spatial cache can be any thing you want to cache.
+        The registery and retrieval of the cache is based on current scale.
+        """
+        scale_key = str(self._scale)
+        if scale_key not in self._spatial_cache:
+            self._spatial_cache[scale_key] = {}
+        self._spatial_cache[scale_key][key] = value
+
+    def get_spatial_cache(self, key=None):
+        """
+        Get a spatial cache.
+        """
+        scale_key = str(self._scale)
+        cur_scale_cache = self._spatial_cache.get(scale_key, {})
+        if key is None:
+            return cur_scale_cache
+        return cur_scale_cache.get(key, None)
+
+
+def sparse_batch_broadcast(input: SparseTensor, other: torch.Tensor) -> torch.Tensor:
+    """
+    Broadcast a 1D tensor to a sparse tensor along the batch dimension then perform an operation.
+    
+    Args:
+        input (torch.Tensor): 1D tensor to broadcast.
+        target (SparseTensor): Sparse tensor to broadcast to.
+        op (callable): Operation to perform after broadcasting. Defaults to torch.add.
+    """
+    coords, feats = input.coords, input.feats
+    broadcasted = torch.zeros_like(feats)
+    for k in range(input.shape[0]):
+        broadcasted[input.layout[k]] = other[k]
+    return broadcasted
+
+
+def sparse_batch_op(input: SparseTensor, other: torch.Tensor, op: callable = torch.add) -> SparseTensor:
+    """
+    Broadcast a 1D tensor to a sparse tensor along the batch dimension then perform an operation.
+    
+    Args:
+        input (torch.Tensor): 1D tensor to broadcast.
+        target (SparseTensor): Sparse tensor to broadcast to.
+        op (callable): Operation to perform after broadcasting. Defaults to torch.add.
+    """
+    return input.replace(op(input.feats, sparse_batch_broadcast(input, other)))
+
+
+def sparse_cat(inputs: List[SparseTensor], dim: int = 0) -> SparseTensor:
+    """
+    Concatenate a list of sparse tensors.
+    
+    Args:
+        inputs (List[SparseTensor]): List of sparse tensors to concatenate.
+    """
+    if dim == 0:
+        start = 0
+        coords = []
+        for input in inputs:
+            coords.append(input.coords.clone())
+            coords[-1][:, 0] += start
+            start += input.shape[0]
+        coords = torch.cat(coords, dim=0)
+        feats = torch.cat([input.feats for input in inputs], dim=0)
+        output = SparseTensor(
+            coords=coords,
+            feats=feats,
+        )
+    else:
+        feats = torch.cat([input.feats for input in inputs], dim=dim)
+        output = inputs[0].replace(feats)
+
+    return output
+
+
+def sparse_unbind(input: SparseTensor, dim: int) -> List[SparseTensor]:
+    """
+    Unbind a sparse tensor along a dimension.
+    
+    Args:
+        input (SparseTensor): Sparse tensor to unbind.
+        dim (int): Dimension to unbind.
+    """
+    if dim == 0:
+        return [input[i] for i in range(input.shape[0])]
+    else:
+        feats = input.feats.unbind(dim)
+        return [input.replace(f) for f in feats]

Stable3DGen/hi3dgen/modules/sparse/conv/__init__.py

@@ -0,0 +1,45 @@
+# MIT License
+
+# Copyright (c) Microsoft
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+# Copyright (c) [2025] [Microsoft]
+# SPDX-License-Identifier: MIT
+from .. import BACKEND
+
+
+SPCONV_ALGO = 'auto'    # 'auto', 'implicit_gemm', 'native'
+
+def __from_env():
+    import os
+        
+    global SPCONV_ALGO
+    env_spconv_algo = os.environ.get('SPCONV_ALGO')
+    if env_spconv_algo is not None and env_spconv_algo in ['auto', 'implicit_gemm', 'native']:
+        SPCONV_ALGO = env_spconv_algo
+    print(f"[SPARSE][CONV] spconv algo: {SPCONV_ALGO}")
+        
+
+__from_env()
+
+if BACKEND == 'torchsparse':
+    from .conv_torchsparse import *
+elif BACKEND == 'spconv':
+    from .conv_spconv import *