RE: Re: Re: vic usability improvements

["Wei Tsang Ooi" <weitsang@bmrc.berkeley.edu>]

Hi Jin Tian,

>   I have test these code in our project. But the conclusion is be 
> careful to use the Tcl_DoOneEvent code in vic. I have meet error 
> when using these code. When the source number is changing and you 
> are titing the video window. Access Error will pop-up (The 
> circumstance is dual CPU, that might cause the error). And I 
> think bob's crash is same problem.

	Since Mash is a single threaded-app, I doubt that 
	dual CPU or no semaphore is the cause of the problem
	(unless I am missing something..).
	
	Do you know exactly where the access error occurred?
	Is it due to a invalid renderer pointer?

	Thanks for reporting the problem!  I am sure we will
	get to the bottom of this.

>   When you are drawing a video window, and also you do OneEvent 
> (maybe source number change). Then the engines_ chain will 
> changed, and some of renderer pointer will be invalid. Due to no 
> semaphore scheme is using, access error might pop-up.
>   I do not know wheather there will happened on mash. But is 
> source number increased, this thing will happened more easily.
>
>   Maybe change the place of Tcl_DoOneEvent will be better.

	I agree that renderer may not be the best place to do this.
	But I cannot think of any better place to poll Tcl UI event
	queue.  Any ideas?

regards,
Wei Tsang