File size: 7,977 Bytes
604e535
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
"""Clean image observations for the boat benchmark."""

from __future__ import annotations

import numpy as np
import torch
from PIL import Image, ImageDraw

from driftwm.sim.boat import BoatSpec, get_boat_spec
from driftwm.sim.dynamics import rot_body_to_world

_GRID_CACHE: dict[tuple[str, str, int, tuple[float, float, float, float], int], tuple[torch.Tensor, torch.Tensor]] = {}
_HULL_CACHE: dict[tuple[str, str, torch.dtype, float], torch.Tensor] = {}


def world_to_pixel(point: np.ndarray, workspace: tuple[float, float, float, float], image_size: int, pad: int) -> tuple[int, int]:
    xmin, xmax, ymin, ymax = workspace
    x = (float(point[0]) - xmin) / (xmax - xmin)
    y = (float(point[1]) - ymin) / (ymax - ymin)
    px = int(round(pad + x * (image_size - 2 * pad)))
    py = int(round(image_size - pad - y * (image_size - 2 * pad)))
    return px, py


def render_clean_boat_image(
    state: np.ndarray,
    boat: str | BoatSpec,
    image_size: int = 64,
    workspace: tuple[float, float, float, float] = (0.0, 10.0, 0.0, 10.0),
    pad: int = 4,
    visual_scale: float = 2.5,
) -> Image.Image:
    spec = get_boat_spec(boat) if isinstance(boat, str) else boat
    img = Image.new("RGB", (image_size, image_size), (246, 249, 251))
    draw = ImageDraw.Draw(img, "RGBA")
    draw.rectangle([pad, pad, image_size - pad, image_size - pad], outline=(70, 82, 94, 255), width=1)
    pos = np.asarray(state[:2], dtype=np.float32)
    rot = rot_body_to_world(float(state[2]))
    hull = ((spec.hull_vertices * float(visual_scale)) @ rot.T) + pos
    pts = [world_to_pixel(p, workspace, image_size, pad) for p in hull]
    draw.polygon(pts, fill=(35, 91, 140, 255), outline=(18, 45, 76, 255))
    bow_marker = ((np.array([0.22, 0.0], dtype=np.float32) * float(visual_scale)) @ rot.T) + pos
    mx, my = world_to_pixel(bow_marker, workspace, image_size, pad)
    radius = max(2, image_size // 40)
    draw.ellipse(
        [mx - radius, my - radius, mx + radius, my + radius],
        fill=(245, 204, 80, 255),
        outline=(94, 65, 12, 255),
    )
    return img


def render_clean_boat_array(
    state: np.ndarray,
    boat: str | BoatSpec,
    image_size: int = 64,
    workspace: tuple[float, float, float, float] = (0.0, 10.0, 0.0, 10.0),
    visual_scale: float = 2.5,
) -> np.ndarray:
    return np.asarray(
        render_clean_boat_image(state, boat, image_size=image_size, workspace=workspace, visual_scale=visual_scale),
        dtype=np.uint8,
    )


def _polygon_mask(body_x: torch.Tensor, body_y: torch.Tensor, vertices: torch.Tensor) -> torch.Tensor:
    inside = torch.zeros_like(body_x, dtype=torch.bool)
    count = int(vertices.shape[0])
    for i in range(count):
        j = (i + 1) % count
        xi, yi = vertices[i, 0], vertices[i, 1]
        xj, yj = vertices[j, 0], vertices[j, 1]
        crosses = (yi > body_y) != (yj > body_y)
        x_at_y = (xj - xi) * (body_y - yi) / (yj - yi + 1.0e-6) + xi
        inside = torch.logical_xor(inside, crosses & (body_x < x_at_y))
    return inside


def render_clean_boat_tensor(
    states: torch.Tensor,
    boat_ids: torch.Tensor,
    image_size: int = 160,
    workspace: tuple[float, float, float, float] = (0.0, 10.0, 0.0, 10.0),
    pad: int = 4,
    visual_scale: float = 2.5,
) -> torch.Tensor:
    """Render a batch of clean boat observations on the tensor device.

    Args:
        states: tensor with shape ``(N, 6)`` containing ``x, y, theta, ...``.
        boat_ids: tensor with shape ``(N,)`` where 0 is twin and 1 is triangle.

    Returns:
        ``uint8`` tensor with shape ``(N, 3, H, W)``.
    """
    if states.ndim != 2 or states.shape[-1] < 3:
        raise ValueError("states must have shape (N, >=3)")
    if boat_ids.ndim != 1 or boat_ids.shape[0] != states.shape[0]:
        raise ValueError("boat_ids must have shape (N,)")
    device = states.device
    n = int(states.shape[0])
    h = int(image_size)
    w = int(image_size)
    dtype = states.dtype
    image = torch.empty((n, 3, h, w), dtype=torch.uint8, device=device)
    background = torch.tensor([246, 249, 251], dtype=torch.uint8, device=device).view(1, 3, 1, 1)
    image.copy_(background.expand_as(image))

    border = torch.tensor([70, 82, 94], dtype=torch.uint8, device=device).view(1, 3, 1)
    image[:, :, pad, pad : w - pad + 1] = border
    image[:, :, h - pad, pad : w - pad + 1] = border
    image[:, :, pad : h - pad + 1, pad] = border
    image[:, :, pad : h - pad + 1, w - pad] = border

    xmin, xmax, ymin, ymax = workspace
    grid_key = (str(device), str(dtype), h, tuple(float(v) for v in workspace), int(pad))
    cached_grid = _GRID_CACHE.get(grid_key)
    if cached_grid is None:
        xs = torch.linspace(xmin, xmax, w - 2 * pad + 1, device=device, dtype=dtype)
        ys = torch.linspace(ymax, ymin, h - 2 * pad + 1, device=device, dtype=dtype)
        full_x = torch.empty((h, w), device=device, dtype=dtype)
        full_y = torch.empty((h, w), device=device, dtype=dtype)
        full_x[:] = xmin - 1.0
        full_y[:] = ymin - 1.0
        full_x[pad : h - pad + 1, pad : w - pad + 1] = xs.view(1, -1)
        full_y[pad : h - pad + 1, pad : w - pad + 1] = ys.view(-1, 1)
        _GRID_CACHE[grid_key] = (full_x, full_y)
    else:
        full_x, full_y = cached_grid

    x = states[:, 0].view(n, 1, 1)
    y = states[:, 1].view(n, 1, 1)
    theta = states[:, 2].view(n, 1, 1)
    cos_t = torch.cos(theta)
    sin_t = torch.sin(theta)
    dx = full_x.view(1, h, w) - x
    dy = full_y.view(1, h, w) - y
    body_x = cos_t * dx + sin_t * dy
    body_y = -sin_t * dx + cos_t * dy

    hull_color = torch.tensor([35, 91, 140], dtype=torch.uint8, device=device).view(1, 3, 1, 1)
    marker_color = torch.tensor([245, 204, 80], dtype=torch.uint8, device=device).view(1, 3, 1, 1)
    radius_world = float(max(2, h // 40)) * float(xmax - xmin) / float(h - 2 * pad)
    marker_x = 0.22 * float(visual_scale)
    marker = (body_x - marker_x).square() + body_y.square() <= radius_world * radius_world

    hull_key_twin = ("twin", str(device), dtype, float(visual_scale))
    hull_key_triangle = ("triangle", str(device), dtype, float(visual_scale))
    twin_vertices = _HULL_CACHE.get(hull_key_twin)
    if twin_vertices is None:
        twin_vertices = torch.as_tensor(get_boat_spec("twin").hull_vertices, dtype=dtype, device=device) * float(visual_scale)
        _HULL_CACHE[hull_key_twin] = twin_vertices
    triangle_vertices = _HULL_CACHE.get(hull_key_triangle)
    if triangle_vertices is None:
        triangle_vertices = torch.as_tensor(get_boat_spec("triangle").hull_vertices, dtype=dtype, device=device) * float(visual_scale)
        _HULL_CACHE[hull_key_triangle] = triangle_vertices
    for boat_id, vertices in [(0, twin_vertices), (1, triangle_vertices)]:
        index = torch.nonzero(boat_ids == boat_id, as_tuple=False).flatten()
        if index.numel() == 0:
            continue
        mask = _polygon_mask(body_x[index], body_y[index], vertices)
        image[index] = torch.where(mask[:, None], hull_color.expand(index.numel(), -1, h, w), image[index])
        image[index] = torch.where(marker[index, None], marker_color.expand(index.numel(), -1, h, w), image[index])
    return image


def render_clean_boat_history_tensor(
    states: torch.Tensor,
    boat_ids: torch.Tensor,
    image_size: int = 160,
    workspace: tuple[float, float, float, float] = (0.0, 10.0, 0.0, 10.0),
    visual_scale: float = 2.5,
) -> torch.Tensor:
    """Render state histories with shape ``(B, T, 6)`` to ``(B, T, 3, H, W)``."""
    if states.ndim != 3:
        raise ValueError("states must have shape (B, T, 6)")
    b, t, d = states.shape
    expanded_boats = boat_ids.view(b, 1).expand(b, t).reshape(b * t)
    rendered = render_clean_boat_tensor(
        states.reshape(b * t, d),
        expanded_boats,
        image_size=image_size,
        workspace=workspace,
        visual_scale=visual_scale,
    )
    return rendered.reshape(b, t, 3, image_size, image_size)