import postprocess;

uniform sampler1D curve;
uniform ToneMapping
{
	float exposure;
	vec3 brightness_response;
};

#pragma MSP stage(fragment)
void main()
{
	vec4 incoming = texture(source, texcoord);
	float maxc = max(incoming.r, max(incoming.g, incoming.b));
	if(maxc>0.0)
	{
		vec3 saturated = incoming.rgb/maxc;
		maxc = pow(maxc*exposure+brightness_response.y, brightness_response.x)-brightness_response.z;
		float c = min(maxc, 1.0);
		float minc = min(saturated.r, min(saturated.g, saturated.b));
		incoming.rgb = mix(saturated, vec3(1.0), min((maxc-c)/(1.0-minc), 1.0))*c;
	}
	frag_color = vec4(texture(curve, incoming.r).r, texture(curve, incoming.g).r, texture(curve, incoming.b).r, incoming.a);
}