Qt Reference Documentation

# RadialWaveEffect.qml Example File

declarative/shadereffects/qml/shadereffects/RadialWaveEffect.qml

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     import QtQuick 1.0
     import Qt.labs.shaders 1.0

     ShaderEffectItem {
         id: effect

         property real wave: 0.3
         property real waveOriginX: 0.5
         property real waveOriginY: 0.5
         property real waveWidth: 0.01
         property real aspectRatio: width/height
         property variant source: 0

         fragmentShader:
             "
             varying mediump vec2 qt_TexCoord0;
             uniform sampler2D source;
             uniform highp float wave;
             uniform highp float waveWidth;
             uniform highp float waveOriginX;
             uniform highp float waveOriginY;
             uniform highp float aspectRatio;

             void main(void)
             {
             mediump vec2 texCoord2 = qt_TexCoord0;
             mediump vec2 origin = vec2(waveOriginX, (1.0 - waveOriginY) / aspectRatio);

             highp float fragmentDistance = distance(vec2(texCoord2.s, texCoord2.t / aspectRatio), origin);
             highp float waveLength = waveWidth + fragmentDistance * 0.25;

             if ( fragmentDistance > wave && fragmentDistance < wave + waveLength) {
                 highp float distanceFromWaveEdge = min(abs(wave - fragmentDistance), abs(wave + waveLength - fragmentDistance));
                 texCoord2 += sin(1.57075 * distanceFromWaveEdge / waveLength) * distanceFromWaveEdge * 0.08 / fragmentDistance;
             }

             gl_FragColor = texture2D(source, texCoord2.st);
             }
             "
     }