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);
         }
         "
 }