Qt Reference Documentation

WaterEffect.qml Example File

declarative/shadereffects/qml/shadereffects/WaterEffect.qml
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 import QtQuick 1.0
 import Qt.labs.shaders 1.0

 Item {
     id: root
     property alias sourceItem: effectsource.sourceItem
     property real intensity: 1
     property bool waving: true
     anchors.top: sourceItem.bottom
     width: sourceItem.width
     height: sourceItem.height

     ShaderEffectItem {
         anchors.fill: parent
         property variant source: effectsource
         property real f: 0
         property real f2: 0
         property alias intensity: root.intensity
         smooth: true

         ShaderEffectSource {
             id: effectsource
             hideSource: false
             smooth: true
         }

         fragmentShader:
             "
             varying highp vec2 qt_TexCoord0;
             uniform sampler2D source;
             uniform lowp float qt_Opacity;
             uniform highp float f;
             uniform highp float f2;
             uniform highp float intensity;

             void main() {
                 const highp float twopi = 3.141592653589 * 2.0;

                 highp float distanceFactorToPhase = pow(qt_TexCoord0.y + 0.5, 8.0) * 5.0;
                 highp float ofx = sin(f * twopi + distanceFactorToPhase) / 100.0;
                 highp float ofy = sin(f2 * twopi + distanceFactorToPhase * qt_TexCoord0.x) / 60.0;

                 highp float intensityDampingFactor = (qt_TexCoord0.x + 0.1) * (qt_TexCoord0.y + 0.2);
                 highp float distanceFactor = (1.0 - qt_TexCoord0.y) * 4.0 * intensity * intensityDampingFactor;

                 ofx *= distanceFactor;
                 ofy *= distanceFactor;

                 highp float x = qt_TexCoord0.x + ofx;
                 highp float y = 1.0 - qt_TexCoord0.y + ofy;

                 highp float fake = (sin((ofy + ofx) * twopi) + 0.5) * 0.05 * (1.2 - qt_TexCoord0.y) * intensity * intensityDampingFactor;

                 highp vec4 pix =
                     texture2D(source, vec2(x, y)) * 0.6 +
                     texture2D(source, vec2(x-fake, y)) * 0.15 +
                     texture2D(source, vec2(x, y-fake)) * 0.15 +
                     texture2D(source, vec2(x+fake, y)) * 0.15 +
                     texture2D(source, vec2(x, y+fake)) * 0.15;

                 highp float darken = 0.6 - (ofx - ofy) / 2.0;
                 pix.b *= 1.2 * darken;
                 pix.r *= 0.9 * darken;
                 pix.g *= darken;

                 gl_FragColor = qt_Opacity * vec4(pix.r, pix.g, pix.b, 1.0);
             }
             "

         NumberAnimation on f {
             running: root.waving
             loops: Animation.Infinite
             from: 0
             to: 1
             duration: 2410
         }
         NumberAnimation on f2 {
             running: root.waving
             loops: Animation.Infinite
             from: 0
             to: 1
             duration: 1754
         }
     }
 }