EffectMagnify.qml Example File | Qt Multimedia 5.4

- Qt 5.4
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- QML Video Shader Effects Example
- EffectMagnify.qml Example File
- Qt 5.4.2 Reference Documentation

# EffectMagnify.qml Example File

video/qmlvideofx/qml/qmlvideofx/EffectMagnify.qml

    /****************************************************************************
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    import QtQuick 2.1
    import QtQuick.Window 2.1

    Effect {
        id: root
        divider: false
        parameters: ListModel {
            ListElement {
                name: "Radius"
                value: 0.5
            }
            ListElement {
                name: "Diffraction"
                value: 0.5
            }
        }

        property real posX: -1
        property real posY: -1
        property real pixDens: Screen.pixelDensity

        QtObject {
            id: d
            property real oldTargetWidth: root.targetWidth
            property real oldTargetHeight: root.targetHeight
        }

        // Transform slider values, and bind result to shader uniforms
        property real radius: parameters.get(0).value * 100
        property real diffractionIndex: parameters.get(1).value

        onTargetWidthChanged: {
            if (posX == -1)
                posX = targetWidth / 2
            else if (d.oldTargetWidth != 0)
                posX *= (targetWidth / d.oldTargetWidth)
            d.oldTargetWidth = targetWidth
        }

        onTargetHeightChanged: {
            if (posY == -1)
                posY = targetHeight / 2
            else if (d.oldTargetHeight != 0)
                posY *= (targetHeight / d.oldTargetHeight)
            d.oldTargetHeight = targetHeight
        }

        fragmentShaderFilename: "magnify.fsh"

        MouseArea {
            anchors.fill: parent
            onPositionChanged: { root.posX = mouse.x; root.posY = root.targetHeight - mouse.y }
        }
    }