uniform sampler2D sceneSampler; // 0
uniform sampler2D depthSampler; // 1

float LinearizeDepth(vec2 uv)
{
  float n = 1.0; // camera z near
  float f = 100.0; // camera z far
  float z = texture2D(depthSampler, uv).x;
  return (2.0 * n) / (f + n - z * (f - n));	
}
void main() 
{ 
  vec2 uv = gl_TexCoord[0].xy;
  //vec4 sceneTexel = texture2D(sceneSampler, uv);
  float d;
  if (uv.x < 0.5) // left part
    d = LinearizeDepth(uv);
  else // right part
    d = texture2D(depthSampler, uv).x;
  
  if (d > 10000 || d < 800)
    d = 0;
  int red = d % 32;
  int green = (d / 32) % 32;
  int blue = (d / 1024) % 32;
  float fRed = float(red) / 32.0;
  float fGreen = float(green) / 32.0;
  float fBlue = float(blue) / 32.0;

  gl_FragColor.rgb = vec4(fRed, fGreen, fBlue, 1.0);
}