Singularity/Library/PackageCache/com.unity.render-pipelines..../Shaders/PostProcessing/LutBuilderLdr.shader
2024-05-06 11:45:45 -07:00

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Shader "Hidden/Universal Render Pipeline/LutBuilderLdr"
{
HLSLINCLUDE
#pragma exclude_renderers gles
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"
#include "Packages/com.unity.render-pipelines.universal/Shaders/PostProcessing/Common.hlsl"
#include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl"
float4 _Lut_Params; // x: lut_height, y: 0.5 / lut_width, z: 0.5 / lut_height, w: lut_height / lut_height - 1
float4 _ColorBalance; // xyz: LMS coeffs, w: unused
half4 _ColorFilter; // xyz: color, w: unused
half4 _ChannelMixerRed; // xyz: rgb coeffs, w: unused
half4 _ChannelMixerGreen; // xyz: rgb coeffs, w: unused
half4 _ChannelMixerBlue; // xyz: rgb coeffs, w: unused
float4 _HueSatCon; // x: hue shift, y: saturation, z: contrast, w: unused
float4 _Lift; // xyz: color, w: unused
float4 _Gamma; // xyz: color, w: unused
float4 _Gain; // xyz: color, w: unused
float4 _Shadows; // xyz: color, w: unused
float4 _Midtones; // xyz: color, w: unused
float4 _Highlights; // xyz: color, w: unused
float4 _ShaHiLimits; // xy: shadows min/max, zw: highlight min/max
half4 _SplitShadows; // xyz: color, w: balance
half4 _SplitHighlights; // xyz: color, w: unused
TEXTURE2D(_CurveMaster);
TEXTURE2D(_CurveRed);
TEXTURE2D(_CurveGreen);
TEXTURE2D(_CurveBlue);
TEXTURE2D(_CurveHueVsHue);
TEXTURE2D(_CurveHueVsSat);
TEXTURE2D(_CurveSatVsSat);
TEXTURE2D(_CurveLumVsSat);
half EvaluateCurve(TEXTURE2D(curve), float t)
{
half x = SAMPLE_TEXTURE2D(curve, sampler_LinearClamp, float2(t, 0.0)).x;
return saturate(x);
}
half4 Frag(Varyings input) : SV_Target
{
float3 colorLinear = GetLutStripValue(input.uv, _Lut_Params);
// White balance in LMS space
float3 colorLMS = LinearToLMS(colorLinear);
colorLMS *= _ColorBalance.xyz;
colorLinear = LMSToLinear(colorLMS);
// Do contrast in log after white balance
float3 colorLog = LinearToLogC(colorLinear);
colorLog = (colorLog - ACEScc_MIDGRAY) * _HueSatCon.z + ACEScc_MIDGRAY;
colorLinear = LogCToLinear(colorLog);
// Color filter is just an unclipped multiplier
colorLinear *= _ColorFilter.xyz;
// Do NOT feed negative values to the following color ops
colorLinear = max(0.0, colorLinear);
// Split toning
// As counter-intuitive as it is, to make split-toning work the same way it does in Adobe
// products we have to do all the maths in gamma-space...
float balance = _SplitShadows.w;
float3 colorGamma = PositivePow(colorLinear, 1.0 / 2.2);
float luma = saturate(GetLuminance(saturate(colorGamma)) + balance);
float3 splitShadows = lerp((0.5).xxx, _SplitShadows.xyz, 1.0 - luma);
float3 splitHighlights = lerp((0.5).xxx, _SplitHighlights.xyz, luma);
colorGamma = SoftLight(colorGamma, splitShadows);
colorGamma = SoftLight(colorGamma, splitHighlights);
colorLinear = PositivePow(colorGamma, 2.2);
// Channel mixing (Adobe style)
colorLinear = float3(
dot(colorLinear, _ChannelMixerRed.xyz),
dot(colorLinear, _ChannelMixerGreen.xyz),
dot(colorLinear, _ChannelMixerBlue.xyz)
);
// Shadows, midtones, highlights
luma = GetLuminance(colorLinear);
float shadowsFactor = 1.0 - smoothstep(_ShaHiLimits.x, _ShaHiLimits.y, luma);
float highlightsFactor = smoothstep(_ShaHiLimits.z, _ShaHiLimits.w, luma);
float midtonesFactor = 1.0 - shadowsFactor - highlightsFactor;
colorLinear = colorLinear * _Shadows.xyz * shadowsFactor
+ colorLinear * _Midtones.xyz * midtonesFactor
+ colorLinear * _Highlights.xyz * highlightsFactor;
// Lift, gamma, gain
colorLinear = colorLinear * _Gain.xyz + _Lift.xyz;
colorLinear = sign(colorLinear) * pow(abs(colorLinear), _Gamma.xyz);
// HSV operations
float satMult;
float3 hsv = RgbToHsv(colorLinear);
{
// Hue Vs Sat
satMult = EvaluateCurve(_CurveHueVsSat, hsv.x) * 2.0;
// Sat Vs Sat
satMult *= EvaluateCurve(_CurveSatVsSat, hsv.y) * 2.0;
// Lum Vs Sat
satMult *= EvaluateCurve(_CurveLumVsSat, Luminance(colorLinear)) * 2.0;
// Hue Shift & Hue Vs Hue
float hue = hsv.x + _HueSatCon.x;
float offset = EvaluateCurve(_CurveHueVsHue, hue) - 0.5;
hue += offset;
hsv.x = RotateHue(hue, 0.0, 1.0);
}
colorLinear = HsvToRgb(hsv);
// Global saturation
luma = GetLuminance(colorLinear);
colorLinear = luma.xxx + (_HueSatCon.yyy * satMult) * (colorLinear - luma.xxx);
// YRGB curves
{
const float kHalfPixel = (1.0 / 128.0) / 2.0;
float3 c = colorLinear;
// Y (master)
c += kHalfPixel.xxx;
float mr = EvaluateCurve(_CurveMaster, c.r);
float mg = EvaluateCurve(_CurveMaster, c.g);
float mb = EvaluateCurve(_CurveMaster, c.b);
c = float3(mr, mg, mb);
// RGB
c += kHalfPixel.xxx;
float r = EvaluateCurve(_CurveRed, c.r);
float g = EvaluateCurve(_CurveGreen, c.g);
float b = EvaluateCurve(_CurveBlue, c.b);
colorLinear = float3(r, g, b);
}
return half4(saturate(colorLinear), 1.0);
}
ENDHLSL
SubShader
{
Tags { "RenderType" = "Opaque" "RenderPipeline" = "UniversalPipeline"}
LOD 100
ZTest Always ZWrite Off Cull Off
Pass
{
Name "LutBuilderLdr"
HLSLPROGRAM
#pragma vertex FullscreenVert
#pragma fragment Frag
ENDHLSL
}
}
}