/* Shader for gamma correction of RGBA textures.
 * Uses standard formula for gamma correction.
 * 'Gamma' is the factor to apply, ie. the inverse gamma 1/G
 * if applying correction for a display with gamma G.
 *
 * This is just a wrapper around icmTransformColor(), so it can be used
 * outside the imaging pipe, e.g., in Screen('TransformTexture') etc...
 * (w)2008 by Mario Kleiner. Licensed under MIT license.
*/

#extension GL_ARB_texture_rectangle : enable

uniform sampler2DRect Image;

vec4 icmTransformColor(vec4 incolor);

void main()
{
    /* Retrieve RGBA input texel, gamma-map and clamp, return as output: */
    gl_FragColor = icmTransformColor(texture2DRect(Image, gl_TexCoord[0].st));
}