BizHawk/Assets/Shaders/BizHawk/bsnes-gamma.hlsl

46 lines
1.1 KiB
HLSL

//https://raw.githubusercontent.com/Themaister/Emulator-Shader-Pack/master/Cg/TV/gamma.cg
/*
Author: Themaister
License: Public domain
*/
// Shader that replicates gamma-ramp of bSNES/Higan.
void main_vertex
(
float4 position : POSITION,
float2 tex : TEXCOORD,
uniform float4x4 modelViewProj,
out float4 oPosition : POSITION,
out float2 oTex : TEXCOORD
)
{
oPosition = mul(modelViewProj, position);
oTex = tex;
}
// Tweakables.
#define saturation 1.0
#define gamma 1.5
#define luminance 1.0
float3 grayscale(float3 col)
{
// Non-conventional way to do grayscale,
// but bSNES uses this as grayscale value.
float v = dot(col, float3(0.3333,0.3333,0.3333));
return float3(v,v,v);
}
float4 main_fragment(in float4 vpos : POSITION, in float2 tex : TEXCOORD, uniform sampler2D s0 : TEXUNIT0) : COLOR
{
float3 res = tex2D(s0, tex).xyz;
res = lerp(grayscale(res), res, saturation); // Apply saturation
res = pow(res, float3(gamma,gamma,gamma)); // Apply gamma
return float4(saturate(res * luminance), 1.0);
}