Methode for incremental Scale (pincharea) of an Image in Qml?

PowerNow

Hi, I'm just looking for a method to 'incremental' Scale an Image in Qml. This means

start pinch at Center.x/y and e.g. increase Scale -> Scale/Zoom into Image starting from point with Center.x/y
stop pinch
start next pinch at different Center.x/y and continue with Scale -> Image jumps to another point and continues with Scale.

The reason for the jump is that Scale always starts with Scaling=1 at current Center.x/y. I need Scale because I use a big Frambufferobject and Flickable leads to new calculation and makes everthing very slow.

import QtQuick 2.6
Rectangle {
    id: iTImag
    state: "start"
    anchors.fill: parent
    color: "#343434"

    Image {
        id: iImage
        width: parent.width
        height: parent.height
        source: Imag.url
        sourceSize.width: width
        fillMode: Image.PreserveAspectFit

        transform:
            Scale {
            	id: iScale
            }
    }

    PinchArea {
        id: iPinchArea
        anchors.fill: parent
        pinch.minimumScale: 1
        pinch.maximumScale: 8

        property real mScale: 1

        onPinchStarted: {
            iScale.xScale = mScale;
            iScale.yScale = mScale;

        }
        onPinchUpdated: {
            console.log("onPinchUpdated");           

            iScale.origin.x = pinch.center.x;
            iScale.origin.y = pinch.center.y;

            mScale += pinch.scale - pinch.previousScale;

            iScale.xScale = mScale;
            iScale.yScale = mScale;
        }
    }
}

Does maybe anyone has an idea?

PowerNow

This helped me really!

https://stackoverflow.com/questions/24478653/how-to-use-qml-scale-element-for-incremental-scaling-with-different-origin/27376997