godot/servers/rendering/renderer_rd/shaders/ssao_downsample.glsl

207 lines
9.1 KiB
GLSL

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2016, Intel Corporation
// 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.
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// File changes (yyyy-mm-dd)
// 2016-09-07: filip.strugar@intel.com: first commit
// 2020-12-05: clayjohn: convert to Vulkan and Godot
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#[compute]
#version 450
#VERSION_DEFINES
layout(local_size_x = 8, local_size_y = 8, local_size_z = 1) in;
layout(push_constant, binding = 1, std430) uniform Params {
vec2 pixel_size;
float z_far;
float z_near;
bool orthogonal;
float radius_sq;
uvec2 pad;
}
params;
layout(set = 0, binding = 0) uniform sampler2D source_depth;
layout(r16f, set = 1, binding = 0) uniform restrict writeonly image2DArray dest_image0; //rename
#ifdef GENERATE_MIPS
layout(r16f, set = 2, binding = 0) uniform restrict writeonly image2DArray dest_image1;
layout(r16f, set = 2, binding = 1) uniform restrict writeonly image2DArray dest_image2;
layout(r16f, set = 2, binding = 2) uniform restrict writeonly image2DArray dest_image3;
#endif
vec4 screen_space_to_view_space_depth(vec4 p_depth) {
if (params.orthogonal) {
vec4 depth = p_depth * 2.0 - 1.0;
return ((depth + (params.z_far + params.z_near) / (params.z_far - params.z_near)) * (params.z_far - params.z_near)) / 2.0;
}
float depth_linearize_mul = params.z_near;
float depth_linearize_add = params.z_far;
// Optimised version of "-cameraClipNear / (cameraClipFar - projDepth * (cameraClipFar - cameraClipNear)) * cameraClipFar"
// Set your depth_linearize_mul and depth_linearize_add to:
// depth_linearize_mul = ( cameraClipFar * cameraClipNear) / ( cameraClipFar - cameraClipNear );
// depth_linearize_add = cameraClipFar / ( cameraClipFar - cameraClipNear );
return depth_linearize_mul / (depth_linearize_add - p_depth);
}
float screen_space_to_view_space_depth(float p_depth) {
if (params.orthogonal) {
float depth = p_depth * 2.0 - 1.0;
return ((depth + (params.z_far + params.z_near) / (params.z_far - params.z_near)) * (params.z_far - params.z_near)) / (2.0 * params.z_far);
}
float depth_linearize_mul = params.z_near;
float depth_linearize_add = params.z_far;
return depth_linearize_mul / (depth_linearize_add - p_depth);
}
#ifdef GENERATE_MIPS
shared float depth_buffer[4][8][8];
float mip_smart_average(vec4 p_depths) {
float closest = min(min(p_depths.x, p_depths.y), min(p_depths.z, p_depths.w));
float fallof_sq = -1.0f / params.radius_sq;
vec4 dists = p_depths - closest.xxxx;
vec4 weights = clamp(dists * dists * fallof_sq + 1.0, 0.0, 1.0);
return dot(weights, p_depths) / dot(weights, vec4(1.0, 1.0, 1.0, 1.0));
}
void prepare_depths_and_mips(vec4 p_samples, uvec2 p_output_coord, uvec2 p_gtid) {
p_samples = screen_space_to_view_space_depth(p_samples);
depth_buffer[0][p_gtid.x][p_gtid.y] = p_samples.w;
depth_buffer[1][p_gtid.x][p_gtid.y] = p_samples.z;
depth_buffer[2][p_gtid.x][p_gtid.y] = p_samples.x;
depth_buffer[3][p_gtid.x][p_gtid.y] = p_samples.y;
imageStore(dest_image0, ivec3(p_output_coord.x, p_output_coord.y, 0), vec4(p_samples.w));
imageStore(dest_image0, ivec3(p_output_coord.x, p_output_coord.y, 1), vec4(p_samples.z));
imageStore(dest_image0, ivec3(p_output_coord.x, p_output_coord.y, 2), vec4(p_samples.x));
imageStore(dest_image0, ivec3(p_output_coord.x, p_output_coord.y, 3), vec4(p_samples.y));
uint depth_array_index = 2 * (p_gtid.y % 2) + (p_gtid.x % 2);
uvec2 depth_array_offset = ivec2(p_gtid.x % 2, p_gtid.y % 2);
ivec2 buffer_coord = ivec2(p_gtid) - ivec2(depth_array_offset);
p_output_coord /= 2;
groupMemoryBarrier();
barrier();
// if (still_alive) <-- all threads alive here
{
float sample_00 = depth_buffer[depth_array_index][buffer_coord.x + 0][buffer_coord.y + 0];
float sample_01 = depth_buffer[depth_array_index][buffer_coord.x + 0][buffer_coord.y + 1];
float sample_10 = depth_buffer[depth_array_index][buffer_coord.x + 1][buffer_coord.y + 0];
float sample_11 = depth_buffer[depth_array_index][buffer_coord.x + 1][buffer_coord.y + 1];
float avg = mip_smart_average(vec4(sample_00, sample_01, sample_10, sample_11));
imageStore(dest_image1, ivec3(p_output_coord.x, p_output_coord.y, depth_array_index), vec4(avg));
depth_buffer[depth_array_index][buffer_coord.x][buffer_coord.y] = avg;
}
bool still_alive = p_gtid.x % 4 == depth_array_offset.x && p_gtid.y % 4 == depth_array_offset.y;
p_output_coord /= 2;
groupMemoryBarrier();
barrier();
if (still_alive) {
float sample_00 = depth_buffer[depth_array_index][buffer_coord.x + 0][buffer_coord.y + 0];
float sample_01 = depth_buffer[depth_array_index][buffer_coord.x + 0][buffer_coord.y + 2];
float sample_10 = depth_buffer[depth_array_index][buffer_coord.x + 2][buffer_coord.y + 0];
float sample_11 = depth_buffer[depth_array_index][buffer_coord.x + 2][buffer_coord.y + 2];
float avg = mip_smart_average(vec4(sample_00, sample_01, sample_10, sample_11));
imageStore(dest_image2, ivec3(p_output_coord.x, p_output_coord.y, depth_array_index), vec4(avg));
depth_buffer[depth_array_index][buffer_coord.x][buffer_coord.y] = avg;
}
still_alive = p_gtid.x % 8 == depth_array_offset.x && depth_array_offset.y % 8 == depth_array_offset.y;
p_output_coord /= 2;
groupMemoryBarrier();
barrier();
if (still_alive) {
float sample_00 = depth_buffer[depth_array_index][buffer_coord.x + 0][buffer_coord.y + 0];
float sample_01 = depth_buffer[depth_array_index][buffer_coord.x + 0][buffer_coord.y + 4];
float sample_10 = depth_buffer[depth_array_index][buffer_coord.x + 4][buffer_coord.y + 0];
float sample_11 = depth_buffer[depth_array_index][buffer_coord.x + 4][buffer_coord.y + 4];
float avg = mip_smart_average(vec4(sample_00, sample_01, sample_10, sample_11));
imageStore(dest_image3, ivec3(p_output_coord.x, p_output_coord.y, depth_array_index), vec4(avg));
}
}
#else
#ifndef USE_HALF_BUFFERS
void prepare_depths(vec4 p_samples, uvec2 p_tid) {
p_samples = screen_space_to_view_space_depth(p_samples);
imageStore(dest_image0, ivec3(p_tid, 0), vec4(p_samples.w));
imageStore(dest_image0, ivec3(p_tid, 1), vec4(p_samples.z));
imageStore(dest_image0, ivec3(p_tid, 2), vec4(p_samples.x));
imageStore(dest_image0, ivec3(p_tid, 3), vec4(p_samples.y));
}
#endif
#endif
void main() {
#ifdef USE_HALF_BUFFERS
#ifdef USE_HALF_SIZE
float sample_00 = texelFetch(source_depth, ivec2(4 * gl_GlobalInvocationID.x + 0, 4 * gl_GlobalInvocationID.y + 0), 0).x;
float sample_11 = texelFetch(source_depth, ivec2(4 * gl_GlobalInvocationID.x + 2, 4 * gl_GlobalInvocationID.y + 2), 0).x;
#else
float sample_00 = texelFetch(source_depth, ivec2(2 * gl_GlobalInvocationID.x + 0, 2 * gl_GlobalInvocationID.y + 0), 0).x;
float sample_11 = texelFetch(source_depth, ivec2(2 * gl_GlobalInvocationID.x + 1, 2 * gl_GlobalInvocationID.y + 1), 0).x;
#endif
sample_00 = screen_space_to_view_space_depth(sample_00);
sample_11 = screen_space_to_view_space_depth(sample_11);
imageStore(dest_image0, ivec3(gl_GlobalInvocationID.xy, 0), vec4(sample_00));
imageStore(dest_image0, ivec3(gl_GlobalInvocationID.xy, 3), vec4(sample_11));
#else //!USE_HALF_BUFFERS
#ifdef USE_HALF_SIZE
ivec2 depth_buffer_coord = 4 * ivec2(gl_GlobalInvocationID.xy);
ivec2 output_coord = ivec2(gl_GlobalInvocationID);
vec2 uv = (vec2(depth_buffer_coord) + 0.5f) * params.pixel_size;
vec4 samples;
samples.x = textureLodOffset(source_depth, uv, 0, ivec2(0, 2)).x;
samples.y = textureLodOffset(source_depth, uv, 0, ivec2(2, 2)).x;
samples.z = textureLodOffset(source_depth, uv, 0, ivec2(2, 0)).x;
samples.w = textureLodOffset(source_depth, uv, 0, ivec2(0, 0)).x;
#else
ivec2 depth_buffer_coord = 2 * ivec2(gl_GlobalInvocationID.xy);
ivec2 output_coord = ivec2(gl_GlobalInvocationID);
vec2 uv = (vec2(depth_buffer_coord) + 0.5f) * params.pixel_size;
vec4 samples = textureGather(source_depth, uv);
#endif
#ifdef GENERATE_MIPS
prepare_depths_and_mips(samples, output_coord, gl_LocalInvocationID.xy);
#else
prepare_depths(samples, gl_GlobalInvocationID.xy);
#endif
#endif
}