[vtkusers] Re: Rendering slowed down after recent CVS update

[Paul Melis]

Sean McBride wrote:

>On 1/16/08 4:24 PM, Paul Melis said:
>
>  
>
>>And another reply to myself...
>>After going back to a CVS version of VTK of October 1st the problem 
>>seems to be gone. So something changed in VTK between october and today 
>>that influences the render performance, probably due to a software 
>>fallback suddenly being used in the NVidia driver.
>>    
>>
>
>Next try Nov 1, Dec 1, etc. until you have it narrowed down to between 2
>days... tedious, but easy.  You'll probably find the problem this way.
>  
>
Well, I made a little script that did all the hard work of checking out 
a CVS version for specific date, configuring it with cmake, building it, 
setting appropriate environment variables and then running a little test 
application. The results indicate that the problems start with commits 
done on October 27. I suspect the changes relating to alpha handing (for 
bug 2347) in vtkOpenGLRenderWindow.cxx and friends, although I don't see 
anything suspicious in the code. Most of the changes seem related to 
depth peeling and using different blending, but I'm not enabling depth 
peeling and are also not using any transparent geometry.

Any ideas?
Paul