FlipBar.qml Example File

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  import QtQuick 2.0

  Item {
      id: container
      property int animDuration: 300
      property Item front: Item {}
      property Item back: Item {}
      property real factor: 0.1 // amount the edges fold in for the 3D effect
      property alias delta: effect.delta
      property Item cur: frontShown ? front : back
      property Item noncur: frontShown ? back : front

      function swap() {
          var tmp = front;
          front = back;
          back = tmp;
          resync();
      }

      width: cur.width
      height: cur.height
      onFrontChanged: resync();
      onBackChanged: resync();

      function resync() {//TODO: Are the items ever actually visible?
          back.parent = container;
          front.parent = container;
          frontShown ? back.visible = false : front.visible = false;
      }

      property bool frontShown: true

      onFrontShownChanged: {
          back.visible = !frontShown
          front.visible = frontShown
      }

      function flipUp(start) {
          effect.visible = true;
          effect.sourceA = effect.source1
          effect.sourceB = effect.source2
          if (start == undefined)
              start = 1.0;
          deltaAnim.from = start;
          deltaAnim.to = 0.0
          dAnim.start();
          frontShown = false;
      }

      function flipDown(start) {
          effect.visible = true;
          effect.sourceA = effect.source1
          effect.sourceB = effect.source2
          if (start == undefined)
              start = 0.0;
          deltaAnim.from = start;
          deltaAnim.to = 1.0
          dAnim.start();
          frontShown = true;
      }

      ShaderEffect {
          id: effect
          width: cur.width
          height: cur.height
          property real factor: container.factor * width
          property real delta: 1.0

          mesh: GridMesh { resolution: Qt.size(8,2) }

          SequentialAnimation on delta {
              id: dAnim
              running: false
              NumberAnimation {
              id: deltaAnim
              duration: animDuration//expose anim
              }
          }

          property variant sourceA: source1
          property variant sourceB: source1
          property variant source1: ShaderEffectSource {
              sourceItem: front
              hideSource: effect.visible
          }

          property variant source2: ShaderEffectSource {
              sourceItem: back
              hideSource: effect.visible
          }

          fragmentShader: "
              uniform lowp float qt_Opacity;
              uniform sampler2D sourceA;
              uniform sampler2D sourceB;
              uniform highp float delta;
              varying highp vec2 qt_TexCoord0;
              void main() {
                  highp vec4 tex = vec4(qt_TexCoord0.x, qt_TexCoord0.y * 2.0, qt_TexCoord0.x, (qt_TexCoord0.y-0.5) * 2.0);
                  highp float shade = clamp(delta*2.0, 0.5, 1.0);
                  highp vec4 col;
                  if (qt_TexCoord0.y < 0.5) {
                      col = texture2D(sourceA, tex.xy) * (shade);
                  } else {
                      col = texture2D(sourceB, tex.zw) * (1.5 - shade);
                      col.w = 1.0;
                  }
                  gl_FragColor = col * qt_Opacity;
              }
          "
          property real h: height
          vertexShader: "
          uniform highp float delta;
          uniform highp float factor;
          uniform highp float h;
          uniform highp mat4 qt_Matrix;
          attribute highp vec4 qt_Vertex;
          attribute highp vec2 qt_MultiTexCoord0;
          varying highp vec2 qt_TexCoord0;
          void main() {
              highp vec4 pos = qt_Vertex;
              if (qt_MultiTexCoord0.y == 0.0)
                  pos.x += factor * (1. - delta) * (qt_MultiTexCoord0.x * -2.0 + 1.0);
              else if (qt_MultiTexCoord0.y == 1.0)
                  pos.x += factor * (delta) * (qt_MultiTexCoord0.x * -2.0 + 1.0);
              else
                  pos.y = delta * h;
              gl_Position = qt_Matrix * pos;
              qt_TexCoord0 = qt_MultiTexCoord0;
          }"

      }
  }