opengl 3.3 renderer shaders

shaders/tonemapping.glsl

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+const float pureWhite = 1.0;
+
+vec3 reinhard(vec3 x)
+{
+//	return x / (x + vec3(1.0));
+
+	// Reinhard tonemapping operator.
+	// see: "Photographic Tone Reproduction for Digital Images", eq. 4
+	float luminance = dot(x, vec3(0.2126, 0.7152, 0.0722));
+	float mappedLuminance = (luminance * (1.0 + luminance/(pureWhite*pureWhite))) / (1.0 + luminance);
+	// Scale color by ratio of average luminances.
+	return (mappedLuminance / luminance) * x;
+}
+
+// https://knarkowicz.wordpress.com/2016/01/06/aces-filmic-tone-mapping-curve/
+vec3 ACESFilm(vec3 x)
+{
+    float a = 2.51f;
+    float b = 0.03f;
+    float c = 2.43f;
+    float d = 0.59f;
+    float e = 0.14f;
+    return (x*(a*x+b))/(x*(c*x+d)+e);
+}
+
+// https://www.slideshare.net/ozlael/hable-john-uncharted2-hdr-lighting
+vec3 filmicF(vec3 x)
+{
+	float A = 0.22f;
+	float B = 0.30f;
+	float C = 0.10f;
+	float D = 0.20f;
+	float E = 0.01f;
+	float F = 0.30f;
+	return ((x*(A*x+C*B)+D*E)/(x*(A*x+B)+D*F)) - E/F;
+}
+
+vec3 filmic(vec3 x)
+{
+	return filmicF(x) / filmicF(vec3(11.2f));
+}
+
+vec4 tonemap(vec4 x)
+{
+//	return FBOUT(vec4(ACESFilm(x.rgb), x.a));
+	return FBOUT(vec4(reinhard(x.rgb), x.a));
+}