// Tencent is pleased to support the open source community by making ncnn available.
//
// Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.
//
// Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// https://opensource.org/licenses/BSD-3-Clause
//
// Unless required by applicable law or agreed to in writing, software distributed
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
// specific language governing permissions and limitations under the License.

#version 450

#if NCNN_fp16_storage
#extension GL_EXT_shader_16bit_storage: require
#endif
#if NCNN_fp16_arithmetic
#extension GL_EXT_shader_explicit_arithmetic_types_float16: require
#endif

#define shape_constant_id_offset 0
layout (constant_id = shape_constant_id_offset + 0) const int dims = 0;
layout (constant_id = shape_constant_id_offset + 1) const int w = 0;
layout (constant_id = shape_constant_id_offset + 2) const int h = 0;
layout (constant_id = shape_constant_id_offset + 3) const int c = 0;
layout (constant_id = shape_constant_id_offset + 4) const int cstep = 0;

#if NCNN_image_shader
layout (binding = 0) uniform unfp sampler3D bottom_blob_3d;
layout (binding = 1, imfmtc4) writeonly uniform unfp image3D top_blob_3d;
layout (binding = 2) uniform unfp sampler3D a;
layout (binding = 3) uniform unfp sampler3D b;
#else
layout (binding = 0) buffer bottom_top_blob { sfpvec4 bottom_top_blob_data[]; };
layout (binding = 1) readonly buffer a { sfpvec4 a_data[]; };
layout (binding = 2) readonly buffer b { sfpvec4 b_data[]; };
#endif

layout (push_constant) uniform parameter
{
    int dims;
    int w;
    int h;
    int c;
    int cstep;
} p;

void main()
{
    int gx = int(gl_GlobalInvocationID.x);
    int gy = int(gl_GlobalInvocationID.y);
    int gz = int(gl_GlobalInvocationID.z);

    if (gx >= psc(w) || gy >= psc(h) || gz >= psc(c))
        return;

#if NCNN_image_shader
    afpvec4 v = image3d_ld4(bottom_blob_3d, ivec3(gx, gy, gz));
#else
    const int gi = gz * psc(cstep) + gy * psc(w) + gx;

    afpvec4 v = buffer_ld4(bottom_top_blob_data, gi);
#endif

    const ivec3 gxyz = ivec3(gx, gy, gz);
    const int abi = gxyz[psc(dims) - 1];

#if NCNN_image_shader
    afpvec4 b = image3d_ld4(b, ivec3(abi, 0, 0));
    afpvec4 a = image3d_ld4(a, ivec3(abi, 0, 0));
#else
    afpvec4 b = buffer_ld4(b_data, abi);
    afpvec4 a = buffer_ld4(a_data, abi);
#endif

    v = b * v + a;

#if NCNN_image_shader
    image3d_st4(top_blob_3d, ivec3(gx, gy, gz), v);
#else
    buffer_st4(bottom_top_blob_data, gi, v);
#endif
}