HitResults

Code

//http://paperjs.org/examples/hit-testing/


var path = new Path.Rectangle({
    size: 200,
    fillColor: 'red',
    position: view.center
})


//WORKS:
function onMouseMove(event) {
    var hitResult = project.hitTest(event.point, {
        fill: true
    })

    if (hitResult){
        if (hitResult && hitResult.item) {
            hitResult.item.fillColor = "green"
            hitResult.item.tweenTo
            project.activeLayer.addChild(hitResult.item)
            hitResult.item.selected = true
        }
    }
    else{
        path.fillColor = 'red'
    }

}