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<languageVersion : 1.0;>

kernel Crossfade
<   namespace : "AIF";
    vendor : "Adobe Systems";
    version : 2;
    description : "Crossfade between two images"; >
{
   parameter float intensity;

   input image4 frontImage;
   input image4 backImage;
   output pixel4 dst;
   
   void evaluatePixel()
   {
        // Acquire the pixel values from both images at the current location
        float4 frontPixel = sampleNearest(frontImage, outCoord());
        float4 backPixel = sampleNearest(backImage, outCoord());
        
        // We set the output to the mix of the two pixels.  The mix function
        // applies the following equation to the pixel values:
        //    (1.0 - intensity) * frontPixel + intensity * backPixel
        dst = mix(frontPixel, backPixel, intensity);
   }
}