/* LinearCombinationOfManyImagesShader.frag.txt
 * A fragment shader that computes a pixel-wise weighted linear combination
 * of two input image textures bound to Image1 and Image2:
 * outimage(x,y) = (Image1Weight * Image1(x,y)) + (Image2Weight * Image2(x,y));
 *
 * This one is e.g., used by the new moglmorpher.m for fast shape morphing
 * on the GPU.
 *
 * (c) 2007 by Mario Kleiner, licensed to you under MIT license.
 */

#extension GL_ARB_texture_rectangle : enable

uniform sampler2DRect Image[gl_MaxTextureImageUnits];
uniform float ImageWeight[gl_MaxTextureImageUnits];

void main()
{
    vec4 imgsum = vec4(0.0);
    int i;

    for (i=0; i < gl_MaxTextureImageUnits; i++) {
        imgsum+= texture2DRect(Image[i], gl_TexCoord[0].st) * ImageWeight[i];
    }

    gl_FragColor = imgsum;
}