added amd and dx11 tonemapping shader.

shader/ToneMap/AMD.glsl

@@ -0,0 +1,62 @@
+//--------------------------------------------------------------------------------------
+// AMD Tonemapper
+//--------------------------------------------------------------------------------------
+// General tonemapping operator, build 'b' term.
+float ColToneB(float hdrMax, float contrast, float shoulder, float midIn, float midOut) 
+{
+    return
+        -((-pow(midIn, contrast) + (midOut*(pow(hdrMax, contrast*shoulder)*pow(midIn, contrast) -
+            pow(hdrMax, contrast)*pow(midIn, contrast*shoulder)*midOut)) /
+            (pow(hdrMax, contrast*shoulder)*midOut - pow(midIn, contrast*shoulder)*midOut)) /
+            (pow(midIn, contrast*shoulder)*midOut));
+}
+
+// General tonemapping operator, build 'c' term.
+float ColToneC(float hdrMax, float contrast, float shoulder, float midIn, float midOut) 
+{
+    return (pow(hdrMax, contrast*shoulder)*pow(midIn, contrast) - pow(hdrMax, contrast)*pow(midIn, contrast*shoulder)*midOut) /
+           (pow(hdrMax, contrast*shoulder)*midOut - pow(midIn, contrast*shoulder)*midOut);
+}
+
+// General tonemapping operator, p := {contrast,shoulder,b,c}.
+float ColTone(float x, vec4 p) 
+{ 
+    float z = pow(x, p.r); 
+    return z / (pow(z, p.g)*p.b + p.a); 
+}
+
+vec3 ToneMapping(vec3 color)
+{
+    const float hdrMax = 16.0; // How much HDR range before clipping. HDR modes likely need this pushed up to say 25.0.
+    const float contrast = 2.0; // Use as a baseline to tune the amount of contrast the tonemapper has.
+    const float shoulder = 1.0; // Likely don<6F>t need to mess with this factor, unless matching existing tonemapper is not working well..
+    const float midIn = 0.18; // most games will have a {0.0 to 1.0} range for LDR so midIn should be 0.18.
+    const float midOut = 0.18; // Use for LDR. For HDR10 10:10:10:2 use maybe 0.18/25.0 to start. For scRGB, I forget what a good starting point is, need to re-calculate.
+
+    float b = ColToneB(hdrMax, contrast, shoulder, midIn, midOut);
+    float c = ColToneC(hdrMax, contrast, shoulder, midIn, midOut);
+
+    #define EPS 1e-6f
+    float peak = max(color.r, max(color.g, color.b));
+    peak = max(EPS, peak);
+
+    vec3 ratio = color / peak;
+    peak = ColTone(peak, vec4(contrast, shoulder, b, c) );
+    // then process ratio
+
+    // probably want send these pre-computed (so send over saturation/crossSaturation as a constant)
+    float crosstalk = 4.0; // controls amount of channel crosstalk
+    float saturation = contrast; // full tonal range saturation control
+    float crossSaturation = contrast*16.0; // crosstalk saturation
+
+    float white = 1.0;
+
+    // wrap crosstalk in transform
+    ratio = pow(abs(ratio), vec3(saturation / crossSaturation));
+    ratio = mix(ratio, vec3(white), vec3(pow(peak, crosstalk)));
+    ratio = pow(abs(ratio), vec3(crossSaturation));
+
+    // then apply ratio to peak
+    color = peak * ratio;
+    return color;
+}

shader/ToneMap/DX11.glsl

@@ -0,0 +1,15 @@
+//--------------------------------------------------------------------------------------
+// The tone mapper used in HDRToneMappingCS11
+//--------------------------------------------------------------------------------------
+vec3 ToneMapping(vec3 color)
+{
+    float  MIDDLE_GRAY = 0.72f;
+    float  LUM_WHITE = 1.5f;
+
+    // Tone mapping
+    color.rgb *= MIDDLE_GRAY;
+    color.rgb *= (1.0f + color/LUM_WHITE);
+    color.rgb /= (1.0f + color);
+    
+    return color;
+}