EffectGaussianBlur.qml Example File

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  // Based on http://www.geeks3d.com/20100909/shader-library-gaussian-blur-post-processing-filter-in-glsl/

  import QtQuick 2.0

  Item {
      id: root
      property bool divider: true
      property real dividerValue: 0.5
      property ListModel parameters: ListModel {
          ListElement {
              name: "Radius"
              value: 0.5
          }
          onDataChanged: updateBlurSize()
      }

      function updateBlurSize()
      {
          if ((targetHeight > 0) && (targetWidth > 0))
          {
              verticalBlurSize = 4.0 * parameters.get(0).value / targetHeight;
              horizontalBlurSize = 4.0 * parameters.get(0).value / targetWidth;
          }
      }

      property alias targetWidth: verticalShader.targetWidth
      property alias targetHeight: verticalShader.targetHeight
      property alias source: verticalShader.source
      property alias horizontalBlurSize: horizontalShader.blurSize
      property alias verticalBlurSize: verticalShader.blurSize

      Effect {
          id: verticalShader
          anchors.fill:  parent
          dividerValue: parent.dividerValue
          property real blurSize: 0.0

          onTargetHeightChanged: {
              updateBlurSize()
          }
          onTargetWidthChanged: {
              updateBlurSize()
          }
          fragmentShaderFilename: "gaussianblur_v.fsh"
      }

      Effect {
          id: horizontalShader
          anchors.fill: parent
          dividerValue: parent.dividerValue
          property real blurSize: 0.0
          fragmentShaderFilename: "gaussianblur_h.fsh"
          source: horizontalShaderSource

          ShaderEffectSource {
              id: horizontalShaderSource
              sourceItem: verticalShader
              smooth: true
              hideSource: true
          }
      }
  }