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

switchGesture bool MgMotion::switchGesture 是否处于单指手势和双指手势切换之间