Acceleration sensor control and basic vision framework

[mardrone] / mardrone / JoyStick.qml

import Qt 4.7

Item {
        id:joystick
        property int xv:(knob.x-(width-knob.width)/2)*(200/(width-knob.width))
        property int yv:(knob.y-(height-knob.height)/2)*(200/(height-knob.height))
        property bool pressed:mouse_area.pressed
        width: 200
        height: 200

        Rectangle {
            id:knob
            x:parent.width/2-width/2
            y:parent.width/2-height/2
            width:20;
            height:20;
            Image {
                anchors.centerIn:parent
                id: knobimage
                source: "joyknob.png"
            }

            //color:"black"
        }
        MouseArea {
            id:mouse_area
            anchors.fill:parent
            drag.minimumX:0
            drag.minimumY:0
            drag.maximumX:parent.width-knob.width
            drag.maximumY:parent.height-knob.height
            drag.target:knob;
            onReleased:{
                knob.x=parent.width/2-knob.width/2;
                knob.y=parent.height/2-knob.height/2;
            }
        }
  }