centerM cmds d2m d2mgs displayMmToModel displayMmToModel displayMmToModel displayMmToModelBox displayMmToModelBox distanceM dragging gestureState gestureType lastPt lastPtM MgMotion point point2 point2M pointM pressDrag startCenterM startDistanceM startPt startPt2 startPt2M startPtM switchGesture velocity view

lastPtM Point2d MgMotion::lastPtM 移动中上一次的位置，模型坐标