ReShade.fxh

#pragma once

#if !defined(__RESHADE__) || __RESHADE__ < 30000
    #error "ReShade 3.0+ is required to use this header file"
#endif

#ifndef RESHADE_DEPTH_INPUT_IS_UPSIDE_DOWN
    #define RESHADE_DEPTH_INPUT_IS_UPSIDE_DOWN 0
#endif

#ifndef RESHADE_DEPTH_INPUT_IS_REVERSED
    #define RESHADE_DEPTH_INPUT_IS_REVERSED 1
#endif

#ifndef RESHADE_DEPTH_INPUT_IS_LOGARITHMIC
    #define RESHADE_DEPTH_INPUT_IS_LOGARITHMIC 0
#endif

#ifndef RESHADE_DEPTH_MULTIPLIER
    #define RESHADE_DEPTH_MULTIPLIER 1
#endif

#ifndef RESHADE_DEPTH_LINEARIZATION_FAR_PLANE
    #define RESHADE_DEPTH_LINEARIZATION_FAR_PLANE 1000.0
#endif

// Above 1 expands coordinates, below 1 contracts and 1 is equal to no scaling on any axis
#ifndef RESHADE_DEPTH_INPUT_Y_SCALE
    #define RESHADE_DEPTH_INPUT_Y_SCALE 1
#endif

#ifndef RESHADE_DEPTH_INPUT_X_SCALE
    #define RESHADE_DEPTH_INPUT_X_SCALE 1
#endif

// An offset to add to the Y coordinate, (+) = move up, (-) = move down
#ifndef RESHADE_DEPTH_INPUT_Y_OFFSET
    #define RESHADE_DEPTH_INPUT_Y_OFFSET 0
#endif

#ifndef RESHADE_DEPTH_INPUT_Y_PIXEL_OFFSET
    #define RESHADE_DEPTH_INPUT_Y_PIXEL_OFFSET 0
#endif

// An offset to add to the X coordinate, (+) = move right, (-) = move left
#ifndef RESHADE_DEPTH_INPUT_X_OFFSET
    #define RESHADE_DEPTH_INPUT_X_OFFSET 0
#endif

#ifndef RESHADE_DEPTH_INPUT_X_PIXEL_OFFSET
    #define RESHADE_DEPTH_INPUT_X_PIXEL_OFFSET 0
#endif

#define BUFFER_PIXEL_SIZE float2(BUFFER_RCP_WIDTH, BUFFER_RCP_HEIGHT)
#define BUFFER_SCREEN_SIZE float2(BUFFER_WIDTH, BUFFER_HEIGHT)
#define BUFFER_ASPECT_RATIO (BUFFER_WIDTH * BUFFER_RCP_HEIGHT)

namespace ReShade
{
    #if defined(__RESHADE_FXC__)
        float GetAspectRatio() { return BUFFER_WIDTH * BUFFER_RCP_HEIGHT; }
        float2 GetPixelSize() { return float2(BUFFER_RCP_WIDTH, BUFFER_RCP_HEIGHT); }
        float2 GetScreenSize() { return float2(BUFFER_WIDTH, BUFFER_HEIGHT); }
        #define AspectRatio GetAspectRatio()
        #define PixelSize GetPixelSize()
        #define ScreenSize GetScreenSize()
    #else
        // These are deprecated and will be removed eventually.
        static const float AspectRatio = BUFFER_WIDTH * BUFFER_RCP_HEIGHT;
        static const float2 PixelSize = float2(BUFFER_RCP_WIDTH, BUFFER_RCP_HEIGHT);
        static const float2 ScreenSize = float2(BUFFER_WIDTH, BUFFER_HEIGHT);
    #endif

    // Global textures and samplers
    texture BackBufferTex : COLOR;
    texture DepthBufferTex : DEPTH;

    sampler BackBuffer { Texture = BackBufferTex; };
    sampler DepthBuffer { Texture = DepthBufferTex; };

    // Helper functions
    float GetLinearizedDepth(float2 texcoord)
    {
        #if RESHADE_DEPTH_INPUT_IS_UPSIDE_DOWN
            texcoord.y = 1.0 - texcoord.y;
        #endif

        texcoord.x /= RESHADE_DEPTH_INPUT_X_SCALE;
        texcoord.y /= RESHADE_DEPTH_INPUT_Y_SCALE;

        #if RESHADE_DEPTH_INPUT_X_PIXEL_OFFSET
            texcoord.x -= RESHADE_DEPTH_INPUT_X_PIXEL_OFFSET * BUFFER_RCP_WIDTH;
        #else // Do not check RESHADE_DEPTH_INPUT_X_OFFSET, since it may be a decimal number, which the preprocessor cannot handle
            texcoord.x -= RESHADE_DEPTH_INPUT_X_OFFSET / 2.000000001;
        #endif

        #if RESHADE_DEPTH_INPUT_Y_PIXEL_OFFSET
            texcoord.y += RESHADE_DEPTH_INPUT_Y_PIXEL_OFFSET * BUFFER_RCP_HEIGHT;
        #else
            texcoord.y += RESHADE_DEPTH_INPUT_Y_OFFSET / 2.000000001;
        #endif

        float depth = tex2Dlod(DepthBuffer, float4(texcoord, 0, 0)).x * RESHADE_DEPTH_MULTIPLIER;

        #if RESHADE_DEPTH_INPUT_IS_LOGARITHMIC
            const float C = 0.01;
            depth = (exp(depth * log(C + 1.0)) - 1.0) / C;
        #endif

        #if RESHADE_DEPTH_INPUT_IS_REVERSED
            depth = 1.0 - depth;
        #endif

        const float N = 1.0;
        depth /= RESHADE_DEPTH_LINEARIZATION_FAR_PLANE - depth * (RESHADE_DEPTH_LINEARIZATION_FAR_PLANE - N);
        return depth;
    }
}

// Vertex shader generating a triangle covering the entire screen
void PostProcessVS(in uint id : SV_VERTEXID, out float4 position : SV_POSITION, out float2 texcoord : TEXCOORD0)
{
    texcoord.x = (id == 2) ? 2.0 : 0.0;
    texcoord.y = (id == 1) ? 2.0 : 0.0;
    position = float4(texcoord * float2(2.0, -2.0) + float2(-1.0, 1.0), 0.0, 1.0);
}