SDL and Stencil Buffer

[3_of_8]

I'm using SDL to get an OpenGL-Handle. I told SDL to set the stencil buffer size to 8.

My problem is, that it seems like the stencil buffer is ignored: I fill it by drawing a quad and then setting glStencilFunc(GL_EQUAL, 1, 1) but OpenGL still renders the complete "mirror world". If I set glStencilFunc(GL_NEVER, 1, 1), it still renders the same, which means everything.

Is there anything important with SDL and the stencil buffer I might have forgotten or I might not know?

[savage]

Can you clarify how you set the stencil buffer to 8 using SDL? Code please.

[savage]

Run glxinfo and look at the visuals listed at the bottom of all that
data it dumps out. Check to see if you have a visual that supports a 8
bit stencil buffer along with all the other buffers you are asking for.
You might find that your card does not have a mode that supports a 8
bit stencil buffer.

To fix the problem you either have to use a mode your video card
supports or buy a video card that supports the mode you need.

[3_of_8]

Like that:

SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);

I'll take a look at that later.

[3_of_8]

It works just fine with the stencil buffer/mirror demo of Sascha Willems which does not use SDL. My code is quite the same as his one. So I suppose it's just some problem with SDL. Not with my graphics card.

[3_of_8]

Alright, that one's fixed.

Next time I got problems with the stencil buffer, could anyone slap me and tell me to set the buffer sizes BEFORE I initialize the video mode?

[technomage]

You should ahve checked out

http://www.cerebral-bicycle.co.uk/viewdoc.asp?doc=307&date=Y

Tells you all you need to know :wink: