add slow-bilateral shader

denoisers/shaders/slow-bilateral.slang

@@ -0,0 +1,82 @@
+#version 450
+
+layout(push_constant) uniform Push
+{
+	vec4 SourceSize;
+	vec4 OriginalSize;
+	vec4 OutputSize;
+	uint FrameCount;
+	float SIGMA;
+	float BSIGMA;
+} params;
+
+#pragma parameter SIGMA "Sigma" 10.0 1.0 20.0 1.0
+#pragma parameter BSIGMA "BSigma" 0.1 0.01 0.5 0.01
+
+layout(std140, set = 0, binding = 0) uniform UBO
+{
+	mat4 MVP;
+} global;
+
+#pragma stage vertex
+layout(location = 0) in vec4 Position;
+layout(location = 1) in vec2 TexCoord;
+layout(location = 0) out vec2 vTexCoord;
+
+void main()
+{
+   gl_Position = global.MVP * Position;
+   vTexCoord = TexCoord;
+}
+
+#pragma stage fragment
+layout(location = 0) in vec2 vTexCoord;
+layout(location = 0) out vec4 FragColor;
+layout(set = 0, binding = 2) uniform sampler2D Source;
+
+#define MSIZE 15
+
+float normpdf(in float x, in float sigma)
+{
+	return 0.39894*exp(-0.5*x*x/(sigma*sigma))/sigma;
+}
+
+float normpdf3(in vec3 v, in float sigma)
+{
+	return 0.39894*exp(-0.5*dot(v,v)/(sigma*sigma))/sigma;
+}
+
+void main()
+{
+	vec2 fragcoord = vTexCoord * params.OutputSize.xy;
+	vec3 c = texture(Source,  (fragcoord.xy / params.OutputSize.xy)).rgb;
+	
+	//declare stuff
+	const int kSize = (MSIZE-1)/2;
+	float kernel[MSIZE];
+	vec3 final_colour = vec3(0.0);
+	
+	//create the 1-D kernel
+	float Z = 0.0;
+	for (int j = 0; j <= kSize; ++j)
+	{
+		kernel[kSize+j] = kernel[kSize-j] = normpdf(float(j), params.SIGMA);
+	}
+	
+	vec3 cc;
+	float factor;
+	float bZ = 1.0/normpdf(0.0, params.BSIGMA);
+	//read out the texels
+	for (int i=-kSize; i <= kSize; ++i)
+	{
+		for (int j=-kSize; j <= kSize; ++j)
+		{
+			cc = texture(Source, (fragcoord.xy+vec2(float(i),float(j))) / params.OutputSize.xy).rgb;
+			factor = normpdf3(cc-c, params.BSIGMA)*bZ*kernel[kSize+j]*kernel[kSize+i];
+			Z += factor;
+			final_colour += factor*cc;
+		}
+	}
+	
+	FragColor = vec4(final_colour/Z, 1.0);
+}

denoisers/slow-bilateral.slangp

@@ -0,0 +1,6 @@
+shaders = 1
+
+shader0 = shaders/slow-bilateral.slang
+scale_type0 = source
+filter_linear0 = true
+scale0 = 1.0