diff --git a/leenkx/Shaders/sss_pass/sss_pass.frag.glsl b/leenkx/Shaders/sss_pass/sss_pass.frag.glsl index 872676f..0b5296f 100644 --- a/leenkx/Shaders/sss_pass/sss_pass.frag.glsl +++ b/leenkx/Shaders/sss_pass/sss_pass.frag.glsl @@ -1,6 +1,7 @@ // // Copyright (C) 2012 Jorge Jimenez (jorge@iryoku.com) // Copyright (C) 2012 Diego Gutierrez (diegog@unizar.es) +// Copyright (C) 2025 Onek8 (info@leenkx.com) // All rights reserved. // // Redistribution and use in source and binary forms, with or without @@ -33,6 +34,14 @@ // policies, either expressed or implied, of the copyright holders. // +// TODO: +// Add real sss radius +// Add real sss scale +// Move temp hash, reorganize shader utility functions +// Add compiler flag for quality presets or with samples parameter +// Clean up + Document comment + + #version 450 #include "compiled.inc" @@ -49,67 +58,93 @@ out vec4 fragColor; const float SSSS_FOVY = 108.0; -// Separable SSS Reflectance -// const float sssWidth = 0.005; +// Temp hash func - +float hash13(vec3 p3) { + p3 = fract(p3 * vec3(0.1031, 0.1030, 0.0973)); + p3 += dot(p3, p3.yzx + 33.33); + return fract((p3.x + p3.y) * p3.z); +} + vec4 SSSSBlur() { - // Quality = 0 - const int SSSS_N_SAMPLES = 11; - vec4 kernel[SSSS_N_SAMPLES]; - kernel[0] = vec4(0.560479, 0.669086, 0.784728, 0); - kernel[1] = vec4(0.00471691, 0.000184771, 5.07566e-005, -2); - kernel[2] = vec4(0.0192831, 0.00282018, 0.00084214, -1.28); - kernel[3] = vec4(0.03639, 0.0130999, 0.00643685, -0.72); - kernel[4] = vec4(0.0821904, 0.0358608, 0.0209261, -0.32); - kernel[5] = vec4(0.0771802, 0.113491, 0.0793803, -0.08); - kernel[6] = vec4(0.0771802, 0.113491, 0.0793803, 0.08); - kernel[7] = vec4(0.0821904, 0.0358608, 0.0209261, 0.32); - kernel[8] = vec4(0.03639, 0.0130999, 0.00643685, 0.72); - kernel[9] = vec4(0.0192831, 0.00282018, 0.00084214, 1.28); - kernel[10] = vec4(0.00471691, 0.000184771, 5.07565e-005, 2); + const int SSSS_N_SAMPLES = 15; + vec4 kernel[SSSS_N_SAMPLES]; + + // color neutral kernel weights to prevent color shifting + kernel[0] = vec4(0.2, 0.2, 0.2, 0.0); + kernel[1] = vec4(0.12, 0.12, 0.12, 0.2); + kernel[2] = vec4(0.09, 0.09, 0.09, 0.4); + kernel[3] = vec4(0.06, 0.06, 0.06, 0.8); + kernel[4] = vec4(0.04, 0.04, 0.04, 1.2); + kernel[5] = vec4(0.025, 0.025, 0.025, 1.6); + kernel[6] = vec4(0.015, 0.015, 0.015, 2.0); + kernel[7] = vec4(0.005, 0.005, 0.005, 2.5); + kernel[8] = vec4(0.12, 0.12, 0.12, -0.2); + kernel[9] = vec4(0.09, 0.09, 0.09, -0.4); + kernel[10] = vec4(0.06, 0.06, 0.06, -0.8); + kernel[11] = vec4(0.04, 0.04, 0.04, -1.2); + kernel[12] = vec4(0.025, 0.025, 0.025, -1.6); + kernel[13] = vec4(0.015, 0.015, 0.015, -2.0); + kernel[14] = vec4(0.005, 0.005, 0.005, -2.5); vec4 colorM = textureLod(tex, texCoord, 0.0); - // Fetch linear depth of current pixel float depth = textureLod(gbufferD, texCoord, 0.0).r; float depthM = cameraProj.y / (depth - cameraProj.x); - // Calculate the sssWidth scale (1.0 for a unit plane sitting on the projection window) float distanceToProjectionWindow = 1.0 / tan(0.5 * radians(SSSS_FOVY)); float scale = distanceToProjectionWindow / depthM; - // Calculate the final step to fetch the surrounding pixels vec2 finalStep = sssWidth * scale * dir; - finalStep *= 1.0;//SSSS_STREGTH_SOURCE; // Modulate it using the alpha channel. - finalStep *= 1.0 / 3.0; // Divide by 3 as the kernels range from -3 to 3. - finalStep *= 0.05; // + - // Accumulate the center sample: - vec4 colorBlurred = colorM; - colorBlurred.rgb *= kernel[0].rgb; - - // Accumulate the other samples + vec3 jitterSeed = vec3(texCoord.xy * 1000.0, fract(cameraProj.x * 0.0001)); + float jitterOffset = (hash13(jitterSeed) * 2.0 - 1.0) * 0.15; // 15% jitteR + + finalStep *= (1.0 + jitterOffset); + finalStep *= 0.05; + vec3 colorBlurred = vec3(0.0); + vec3 weightSum = vec3(0.0); + colorBlurred += colorM.rgb * kernel[0].rgb; + weightSum += kernel[0].rgb; + + // Accumulate the other samples with per-pixel jittering to reduce banding for (int i = 1; i < SSSS_N_SAMPLES; i++) { - // Fetch color and depth for current sample - vec2 offset = texCoord + kernel[i].a * finalStep; + float sampleJitter = hash13(vec3(texCoord.xy * 720.0, float(i) * 37.45)) * 0.1 - 0.05; + + vec2 offset = texCoord + (kernel[i].a + sampleJitter) * finalStep; vec4 color = textureLod(tex, offset, 0.0); - //#if SSSS_FOLLOW_SURFACE == 1 - // If the difference in depth is huge, we lerp color back to "colorM": - //float depth = textureLod(tex, offset, 0.0).r; - //float s = clamp(300.0f * distanceToProjectionWindow * sssWidth * abs(depthM - depth),0.0,1.0); - //color.rgb = mix(color.rgb, colorM.rgb, s); - //#endif - // Accumulate - colorBlurred.rgb += kernel[i].rgb * color.rgb; + + // ADJUST FOR SURFACE FOLLOWING + // 0.0 = disabled (maximum SSS but with bleeding), 1.0 = fully enabled (prevents bleeding but might reduce SSS effect) + const float SURFACE_FOLLOWING_STRENGTH = 0.15; // Reduced to preserve more SSS effect + + if (SURFACE_FOLLOWING_STRENGTH > 0.0) { + float sampleDepth = textureLod(gbufferD, offset, 0.0).r; + float depthScale = 5.0; + float depthDiff = abs(depth - sampleDepth) * depthScale; + if (depthDiff > 0.3) { + float blendFactor = clamp(depthDiff - 0.3, 0.0, 1.0) * SURFACE_FOLLOWING_STRENGTH; + color.rgb = mix(color.rgb, colorM.rgb, blendFactor); + } + } + + colorBlurred += color.rgb * kernel[i].rgb; + weightSum += kernel[i].rgb; } - - return colorBlurred; + vec3 normalizedColor = colorBlurred / max(weightSum, vec3(0.00001)); + float dither = hash13(vec3(texCoord * 1333.0, 0.0)) * 0.003 - 0.0015; + return vec4(normalizedColor + vec3(dither), colorM.a); } void main() { + if (textureLod(gbuffer0, texCoord, 0.0).a == 8192.0) { - fragColor = clamp(SSSSBlur(), 0.0, 1.0); - } - else { + vec4 originalColor = textureLod(tex, texCoord, 0.0); + vec4 blurredColor = SSSSBlur(); + vec4 finalColor = mix(blurredColor, originalColor, 0.15); + + fragColor = clamp(finalColor, 0.0, 1.0); + } else { fragColor = textureLod(tex, texCoord, 0.0); } }