maxscript 在长时间的循环loop运算中卡主，白屏的解决方法 windows.processPostedMessages()
在循环中加入：windows.processPostedMessages()
这是官方解析：
Runs a message pump that retrieves any pending Window's messages and dispatches them to 3ds Max.
Calling this method will process all pending messages. It can be used inside a MAXScript loop which would otherwise cause a "white screen" in Windows 7 due to 3ds Max being unresponsive while performing long calculations.