uniform sampler2DRect colorSampler;

uniform vec3 minMaxMean;
uniform float gamma;

layout(location = 0)out vec4 outColor;

void main(void) {
    ivec2 pos = ivec2(gl_FragCoord.xy);
    vec3 color = texelFetch(colorSampler, pos).xyz;

    //vec3 mapped = (color-minMaxMean.r)/(minMaxMean.g-minMaxMean.r);
    // Exposure tone mapping
    vec3 mapped = vec3(1.0) - exp(-color * 0.5/minMaxMean.b);

    // Gamma correction
    mapped = pow(mapped, vec3(1.0 / gamma));

    outColor = vec4(mapped, 1.0);
}