1 files changed, 123 insertions, 0 deletions
diff --git a/servers/rendering/renderer_rd/shaders/effects/ssao_importance_map.glsl b/servers/rendering/renderer_rd/shaders/effects/ssao_importance_map.glsl
new file mode 100644
index 0000000000..04f98964e8
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+++ b/servers/rendering/renderer_rd/shaders/effects/ssao_importance_map.glsl
@@ -0,0 +1,123 @@
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// 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;
+
+#ifdef GENERATE_MAP
+layout(set = 0, binding = 0) uniform sampler2DArray source_texture;
+#else
+layout(set = 0, binding = 0) uniform sampler2D source_importance;
+#endif
+layout(r8, set = 1, binding = 0) uniform restrict writeonly image2D dest_image;
+
+#ifdef PROCESS_MAPB
+layout(set = 2, binding = 0, std430) buffer Counter {
+	uint sum;
+}
+counter;
+#endif
+
+layout(push_constant, std430) uniform Params {
+	vec2 half_screen_pixel_size;
+	float intensity;
+	float power;
+}
+params;
+
+void main() {
+	// Pixel being shaded
+	ivec2 ssC = ivec2(gl_GlobalInvocationID.xy);
+
+#ifdef GENERATE_MAP
+	// importance map stuff
+	uvec2 base_position = ssC * 2;
+
+	vec2 base_uv = (vec2(base_position) + vec2(0.5f, 0.5f)) * params.half_screen_pixel_size;
+
+	float minV = 1.0;
+	float maxV = 0.0;
+	for (int i = 0; i < 4; i++) {
+		vec4 vals = textureGather(source_texture, vec3(base_uv, i));
+
+		// apply the same modifications that would have been applied in the main shader
+		vals = params.intensity * vals;
+
+		vals = 1 - vals;
+
+		vals = pow(clamp(vals, 0.0, 1.0), vec4(params.power));
+
+		maxV = max(maxV, max(max(vals.x, vals.y), max(vals.z, vals.w)));
+		minV = min(minV, min(min(vals.x, vals.y), min(vals.z, vals.w)));
+	}
+
+	float min_max_diff = maxV - minV;
+
+	imageStore(dest_image, ssC, vec4(pow(clamp(min_max_diff * 2.0, 0.0, 1.0), 0.8)));
+#endif
+
+#ifdef PROCESS_MAPA
+	vec2 uv = (vec2(ssC) + 0.5f) * params.half_screen_pixel_size * 2.0;
+
+	float centre = textureLod(source_importance, uv, 0.0).x;
+
+	vec2 half_pixel = params.half_screen_pixel_size;
+
+	vec4 vals;
+	vals.x = textureLod(source_importance, uv + vec2(-half_pixel.x * 3, -half_pixel.y), 0.0).x;
+	vals.y = textureLod(source_importance, uv + vec2(+half_pixel.x, -half_pixel.y * 3), 0.0).x;
+	vals.z = textureLod(source_importance, uv + vec2(+half_pixel.x * 3, +half_pixel.y), 0.0).x;
+	vals.w = textureLod(source_importance, uv + vec2(-half_pixel.x, +half_pixel.y * 3), 0.0).x;
+
+	float avg = dot(vals, vec4(0.25, 0.25, 0.25, 0.25));
+
+	imageStore(dest_image, ssC, vec4(avg));
+#endif
+
+#ifdef PROCESS_MAPB
+	vec2 uv = (vec2(ssC) + 0.5f) * params.half_screen_pixel_size * 2.0;
+
+	float centre = textureLod(source_importance, uv, 0.0).x;
+
+	vec2 half_pixel = params.half_screen_pixel_size;
+
+	vec4 vals;
+	vals.x = textureLod(source_importance, uv + vec2(-half_pixel.x, -half_pixel.y * 3), 0.0).x;
+	vals.y = textureLod(source_importance, uv + vec2(+half_pixel.x * 3, -half_pixel.y), 0.0).x;
+	vals.z = textureLod(source_importance, uv + vec2(+half_pixel.x, +half_pixel.y * 3), 0.0).x;
+	vals.w = textureLod(source_importance, uv + vec2(-half_pixel.x * 3, +half_pixel.y), 0.0).x;
+
+	float avg = dot(vals, vec4(0.25, 0.25, 0.25, 0.25));
+
+	imageStore(dest_image, ssC, vec4(avg));
+
+	// sum the average; to avoid overflowing we assume max AO resolution is not bigger than 16384x16384; so quarter res (used here) will be 4096x4096, which leaves us with 8 bits per pixel
+	uint sum = uint(clamp(avg, 0.0, 1.0) * 255.0 + 0.5);
+
+	// save every 9th to avoid InterlockedAdd congestion - since we're blurring, this is good enough; compensated by multiplying load_counter_avg_div by 9
+	if (((ssC.x % 3) + (ssC.y % 3)) == 0) {
+		atomicAdd(counter.sum, sum);
+	}
+#endif
+}