Finally the opengl.org server is up again. I posted this on other forums without getting replies so, I really can’t wait to see how it goes in the beginner’s forum and I decided to post directly here.
I am having a problem with WGL_ARB_buffer_region. I am doing a simple experiment before integrating the thing in a larger project, here’s what’s happening.
1- Set viewport and projection.
2- Clear depth and color (blue).
3- Draw a white triangle which fills half screen.
4- Save this to buffer region ‘before’.
5- Set viewport and projection again (different).
6- Clear depth and color (green).
7- Draw a black triangle.
8- Restore buffer ‘before’.
This works nicely. I get the white triangle on blue background. This is essentially the extension’s conformance test.
Now, I add another ‘pass’ between (7) and (8) which is saving the black triangle on green background in a buffer region called ‘new’. I’ll refer to this as (a).
(a) Save to ‘new’
This causes the window to pop up and close automatically before I can see something. The window is displayed for a second or so.
I checked for error codes but looks like everything is going ok.
I figured out I can also do I figured out I can do 1-2-3-4-5-6-7-a and get the window correcltly (which however, displays the black triangle on green background).
An interesting fact is that if I do I 1-2-3-4-5-6-7-a and then try to free up the buffer memory by doing wglSaveBufferRegionARB(before, 0, 0, 0, 0) (which is specified to just release memory) the window pops up for a sec, displays the white triangle on blue background and then closes.
My error checking routines are not able to tell me something interesting but looks like everything is fine up to “SaveBuffer(before)”. Looks like this call is badly failing.
In case someone thinks hw/sw details are necessay (bug), here’s the most relevant info:
AthlonXP 1800+, VIA-KT333 based mobo, GeForce4Ti 128MB, unpatched win2000, 43.45 NV driver.
Other informations will be given if you feel this is necessary, but I feel it won’t.
Is there something I am doing wrong? Could it be a bug? Suggestions? I am really worried by this since I can’t do it w/o buffer regions… read/drawPixels is way too slow.