/**
         * @private
         * returns the stage point relative to the render canvas
         */
        private function canvasPointFor(stageX:Number, stageY:Number):Point {
            _stagePt.x = stageX;
            _stagePt.y = stageY;

            return _mcr.renderCanvas.globalToLocal(_stagePt);
        }

        /**
         * @private
         * converts a mouse event point to screen coordinates
         */
        private function pointInWorld( event:MouseEvent ):Vector3D {
            _halfPoint.x = _mcr.config.tileWidth * 0.5;
            _halfPoint.y = -_mcr.config.tileHeight * 0.5;

            return positionMap.mapToWorld(
                canvasPointFor(event.stageX, event.stageY)
                .add(view.viewport.topLeft)
                .add(_halfPoint));
        }

        /**
         * @private
         * converts a point to a tile position
         */
        private function tileInWorld( event:MouseEvent ):Vector3D {
            return positionMap.mapWorldToTile(pointInWorld(event));
        }