bgfx/examples/39-assao/cs_assao_smart_blur.sc
Бранимир Караџић 4581f14cd4 Happy New Year!
2022-01-15 11:59:06 -08:00

83 lines
2.9 KiB
Python

/*
* Copyright 2018 Attila Kocsis. All rights reserved.
* License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE
*/
#include "bgfx_compute.sh"
#include "uniforms.sh"
IMAGE2D_ARRAY_WR(s_target, rg8, 0);
SAMPLER2DARRAY(s_blurInput, 1);
// unpacking for edges; 2 bits per edge mean 4 gradient values (0, 0.33, 0.66, 1) for smoother transitions!
vec4 UnpackEdges( float _packedVal )
{
uint packedVal = uint(_packedVal * 255.5);
vec4 edgesLRTB;
edgesLRTB.x = float((packedVal >> 6) & 0x03) / 3.0; // there's really no need for mask (as it's an 8 bit input) but I'll leave it in so it doesn't cause any trouble in the future
edgesLRTB.y = float((packedVal >> 4) & 0x03) / 3.0;
edgesLRTB.z = float((packedVal >> 2) & 0x03) / 3.0;
edgesLRTB.w = float((packedVal >> 0) & 0x03) / 3.0;
return saturate( edgesLRTB + u_invSharpness );
}
// ********************************************************************************************************
// Pixel shader that does smart blurring (to avoid bleeding)
void AddSample( float ssaoValue, float edgeValue, inout float sum, inout float sumWeight )
{
float weight = edgeValue;
sum += (weight * ssaoValue);
sumWeight += weight;
}
vec2 SampleBlurred( ivec2 inPos, vec2 coord )
{
float packedEdges = texelFetch(s_blurInput, ivec3(inPos.xy,0.0), 0 ).y;
vec4 edgesLRTB = UnpackEdges( packedEdges );
#if BGFX_SHADER_LANGUAGE_GLSL
vec4 valuesUL = textureGather(s_blurInput, vec3(coord - u_halfViewportPixelSize * 0.5 + vec2(0.0,u_halfViewportPixelSize.y), 0.0), 0).wzyx;
vec4 valuesBR = textureGather(s_blurInput, vec3(coord + u_halfViewportPixelSize * 0.5 + vec2(0.0,-u_halfViewportPixelSize.y), 0.0), 0).wzyx;
#else
vec4 valuesUL = textureGather(s_blurInput, vec3(coord - u_halfViewportPixelSize * 0.5, 0.0), 0);
vec4 valuesBR = textureGather(s_blurInput, vec3(coord + u_halfViewportPixelSize * 0.5, 0.0), 0);
#endif
float ssaoValue = valuesUL.y;
float ssaoValueL = valuesUL.x;
float ssaoValueT = valuesUL.z;
float ssaoValueR = valuesBR.z;
float ssaoValueB = valuesBR.x;
float sumWeight = 0.5f;
float sum = ssaoValue * sumWeight;
AddSample( ssaoValueL, edgesLRTB.x, sum, sumWeight );
AddSample( ssaoValueR, edgesLRTB.y, sum, sumWeight );
AddSample( ssaoValueT, edgesLRTB.z, sum, sumWeight );
AddSample( ssaoValueB, edgesLRTB.w, sum, sumWeight );
float ssaoAvg = sum / sumWeight;
ssaoValue = ssaoAvg; //min( ssaoValue, ssaoAvg ) * 0.2 + ssaoAvg * 0.8;
return vec2( ssaoValue, packedEdges );
}
// edge-sensitive blur
NUM_THREADS(8, 8, 1)
void main()
{
uvec2 dtID = uvec2(gl_GlobalInvocationID.xy) + uvec2(u_rect.xy);
if (all(lessThan(dtID.xy, u_rect.zw) ) )
{
vec2 inUV = (dtID.xy+vec2(0.5,0.5)) * u_halfViewportPixelSize;
imageStore(s_target, ivec3(dtID.xy, u_layer), SampleBlurred( ivec2(dtID.xy), inUV ).xyyy);
}
}