import QtQuick 2.4
import QtQuick.Controls 1.3

Flickable {
    id: viewport
    contentWidth: image.width * image.scale
    contentHeight: image.height * image.scale
    clip: true

    MouseArea {
        id: zoomMouseArea
        anchors.fill: parent
        acceptedButtons: Qt.Wheel
        hoverEnabled: false
        onWheel: {
            var newScale = image.scale * Math.pow(Math.sqrt(4),
                                                  wheel.angleDelta.y / 120)
            var scaleCoef = newScale / image.scale
            var dx = wheel.x - viewport.contentX
            var dy = wheel.y - viewport.contentY
            var posx = (wheel.x) * scaleCoef - dx
            var posy = (wheel.y) * scaleCoef - dy

            console.log(newScale, dx, dy, wheel.x, wheel.y)

            viewport.contentX = posx
            viewport.contentY = posy

            image.scale = newScale
        }
    }

    Image {
        id: image
        source: "file:///home/bulkin/Pictures/wmii01.png"
        asynchronous: true
        cache: false
        mipmap: true
        transformOrigin: Item.TopLeft
    }
}