vec3 Uncharted2Tonemap(vec3 x)
{
  float a = 0.15;
  float b = 0.50;
  float c = 0.10;
  float d = 0.20;
  float e = 0.02;
  float f = 0.30;

  return ((x*(a*x+c*b)+d*e)/(x*(a*x+b)+d*f))-e/f;
}

void main()
{
	vec2 uv = gl_FragCoord.xy / u_resolution;
	vec4 sampledInput = texture(t_input, uv);
	vec4 hdr = vec4(sampledInput.rgb * exposure, sampledInput.a);
	hdr.rgb = Uncharted2Tonemap(hdr.rgb) / Uncharted2Tonemap(whitepoint.rgb);
	
	out_color0.rgba = hdr;
}