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// Based on http://www.geeks3d.com/20101029/shader-library-pixelation-post-processing-effect-glsl/

uniform float dividerValue;
uniform float granularity;
uniform float targetWidth;
uniform float targetHeight;

uniform sampler2D source;
uniform lowp float qt_Opacity;
varying vec2 qt_TexCoord0;

void main()
{
    vec2 uv = qt_TexCoord0.xy;
    vec2 tc = qt_TexCoord0;
    if (uv.x < dividerValue && granularity > 0.0) {
        float dx = granularity / targetWidth;
        float dy = granularity / targetHeight;
        tc = vec2(dx*(floor(uv.x/dx) + 0.5),
                  dy*(floor(uv.y/dy) + 0.5));
    }
    gl_FragColor = qt_Opacity * texture2D(source, tc);
}
