LNXSDK/leenkx/Shaders/bloom_pass/downsample_pass.frag.glsl
2025-01-22 16:18:30 +01:00

80 lines
2.5 KiB
GLSL

#version 450
#include "compiled.inc" // bloomKnee, bloomThreshold
#include "std/resample.glsl"
uniform sampler2D tex;
uniform vec2 screenSizeInv;
uniform int currentMipLevel;
#ifdef _CPostprocess
uniform vec4 BloomThresholdData; // Only filled with data if currentMipLevel == 0
#endif
in vec2 texCoord;
out vec4 fragColor;
const float epsilon = 6.2e-5; // see https://github.com/keijiro/KinoBloom/issues/15
#ifdef _BloomAntiFlicker
const bool antiFlicker = true;
#else
const bool antiFlicker = false;
#endif
void main() {
if (antiFlicker && currentMipLevel == 0) {
#ifdef _BloomQualityHigh
fragColor.rgb = downsample_13_tap_anti_flicker(tex, texCoord, screenSizeInv);
#else
#ifdef _BloomQualityMedium
fragColor.rgb = downsample_dual_filter_anti_flicker(tex, texCoord, screenSizeInv);
#else // _BloomQualityLow
fragColor.rgb = downsample_box_filter_anti_flicker(tex, texCoord, screenSizeInv);
#endif
#endif
}
else {
#ifdef _BloomQualityHigh
fragColor.rgb = downsample_13_tap(tex, texCoord, screenSizeInv);
#else
#ifdef _BloomQualityMedium
fragColor.rgb = downsample_dual_filter(tex, texCoord, screenSizeInv);
#else // _BloomQualityLow
fragColor.rgb = downsample_box_filter(tex, texCoord, screenSizeInv);
#endif
#endif
}
if (currentMipLevel == 0) {
// https://catlikecoding.com/unity/tutorials/advanced-rendering/bloom/#3.2
// https://catlikecoding.com/unity/tutorials/advanced-rendering/bloom/#3.4
float brightness = max(fragColor.r, max(fragColor.g, fragColor.b));
#ifdef _CPostprocess
// Only apply precalculation optimization if _CPostprocess, otherwise
// the compiler is able to do the same optimization for the constant
// values from compiled.inc without the need to pass a uniform
float softeningCurve = brightness - BloomThresholdData.y;
softeningCurve = clamp(softeningCurve, 0.0, BloomThresholdData.z); // "connect" to hard knee curve
softeningCurve = softeningCurve * softeningCurve * BloomThresholdData.w;
float contributionFactor = max(softeningCurve, brightness - BloomThresholdData.x);
#else
float softeningCurve = brightness - bloomThreshold + bloomKnee;
softeningCurve = clamp(softeningCurve, 0.0, 2.0 * bloomKnee);
softeningCurve = softeningCurve * softeningCurve / (4 * bloomKnee + epsilon);
float contributionFactor = max(softeningCurve, brightness - bloomThreshold);
#endif
contributionFactor /= max(epsilon, brightness);
fragColor.rgb *= contributionFactor;
}
fragColor.a = 1.0;
}