slang-shaders/crt/shaders/guest/lut/lut.slang
2019-05-03 12:31:31 -05:00

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#version 450
layout(push_constant) uniform Push
{
vec4 SourceSize;
vec4 OriginalSize;
vec4 OutputSize;
uint FrameCount;
float TNTC;
} params;
#pragma parameter TNTC "LUT Colors" 0.0 0.0 3.0 1.0
#define TNTC params.TNTC
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;
layout(set = 0, binding = 3) uniform sampler2D SamplerLUT1;
layout(set = 0, binding = 4) uniform sampler2D SamplerLUT2;
layout(set = 0, binding = 5) uniform sampler2D SamplerLUT3;
#define LUT_Size 32.0
#define COMPAT_TEXTURE(c,d) texture(c,d)
const mat3 D65_to_XYZ = mat3 (
0.4306190, 0.2220379, 0.0201853,
0.3415419, 0.7066384, 0.1295504,
0.1783091, 0.0713236, 0.9390944);
const mat3 XYZ_to_D50 = mat3 (
2.9603944, -0.9787684, 0.0844874,
-1.4678519, 1.9161415, -0.2545973,
-0.4685105, 0.0334540, 1.4216174);
// This shouldn't be necessary but it seems some undefined values can
// creep in and each GPU vendor handles that differently. This keeps
// all values within a safe range
vec4 mixfix(vec4 a, vec4 b, float c)
{
return (a.z < 1.0) ? mix(a, b, c) : a;
}
void main()
{
vec4 imgColor = COMPAT_TEXTURE(Source, vTexCoord.xy);
float red = ( imgColor.r * (LUT_Size - 1.0) + 0.499999 ) / (LUT_Size * LUT_Size);
float green = ( imgColor.g * (LUT_Size - 1.0) + 0.499999 ) / LUT_Size;
float blue1 = (floor( imgColor.b * (LUT_Size - 1.0) ) / LUT_Size) + red;
float blue2 = (ceil( imgColor.b * (LUT_Size - 1.0) ) / LUT_Size) + red;
float mixer = clamp(max((imgColor.b - blue1) / (blue2 - blue1), 0.0), 0.0, 32.0);
vec4 color1, color2, res;
if (int(TNTC) == 1)
{
color1 = COMPAT_TEXTURE( SamplerLUT1, vec2( blue1, green ));
color2 = COMPAT_TEXTURE( SamplerLUT1, vec2( blue2, green ));
res = mixfix(color1, color2, mixer);
float mx = max(res.r,max(res.g,res.b));
float l = mix(length(imgColor.rgb), length(res.rgb), max(mx-0.5,0.0));
res.rgb = mix(imgColor.rgb, res.rgb, clamp(25.0*(mx-0.02),0.0,1.0));
res.rgb = normalize(res.rgb+1e-10)*l;
vec3 cooler = D65_to_XYZ*res.rgb;
cooler = XYZ_to_D50*cooler;
res.rgb = mix(res.rgb, cooler, 0.25);
}
else if (int(TNTC) == 2)
{
color1 = COMPAT_TEXTURE( SamplerLUT2, vec2( blue1, green ));
color2 = COMPAT_TEXTURE( SamplerLUT2, vec2( blue2, green ));
res = mixfix(color1, color2, mixer);
float l = mix(length(imgColor.rgb), length(res.rgb), 0.4);
res.rgb = normalize(res.rgb + 1e-10)*l;
}
else if (int(TNTC) == 3)
{
color1 = COMPAT_TEXTURE( SamplerLUT3, vec2( blue1, green ));
color2 = COMPAT_TEXTURE( SamplerLUT3, vec2( blue2, green ));
res = mixfix(color1, color2, mixer);
res.rgb = pow(res.rgb, vec3(1.0/1.20));
float mx = max(res.r,max(res.g,res.b));
res.rgb = mix(imgColor.rgb, res.rgb, clamp(25.0*(mx-0.05),0.0,1.0));
float l = length(imgColor.rgb);
res.rgb = normalize(res.rgb + 1e-10)*l;
}
FragColor = vec4(mix(imgColor.rgb, res.rgb, min(TNTC,1.0)),1.0);
}