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** This file is part of the Qt Mobility Components.
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** ensure the GNU Lesser General Public License version 2.1 requirements
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import QtQuick 2.0

Effect {
    parameters: ListModel {
        ListElement {
            name: "gamma"
            value: 0.5
        }
    }

    // Transform slider values, and bind result to shader uniforms
    property real gamma: parameters.get(0).value

    property real numColors: 8.0

    fragmentShaderSrc: "uniform float dividerValue;
                        uniform float gamma;
                        uniform float numColors;

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

                        void main()
                        {
                            vec2 uv = qt_TexCoord0.xy;
                            vec4 c = vec4(0.0);
                            if (uv.x < dividerValue) {
                                vec3 x = texture2D(source, uv).rgb;
                                x = pow(x, vec3(gamma, gamma, gamma));
                                x = x * numColors;
                                x = floor(x);
                                x = x / numColors;
                                x = pow(x, vec3(1.0/gamma));
                                c = vec4(x, 1.0);
                            } else {
                                c = texture2D(source, uv);
                            }
                            gl_FragColor = qt_Opacity * c;
                        }"
}