Hi,

I am having compatibility issues between graphic cards, when using FBO and stencil buffers: it only works correctly on ATI cards, NVidia (GeForce GT 620) and Intel (HD Graphics 4000) fail (they operate as if the stencil buffers were not enabled). I made sure I had the last drivers. Any idea what I am doing wrong, or what is going on?

Here my code:

glGenFramebuffersEXT(1,&_fbo);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT,_fbo);
        
glGenRenderbuffersEXT(1,&_fboDepthBuffer);
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT,_fboDepthBuffer);
glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT,GL_DEPTH24_STENCIL8_EXT,resX,resY);
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,GL_DEPTH_ATTACHMENT_EXT,GL_RENDERBUFFER_EXT,_fboDepthBuffer);

glGenRenderbuffersEXT(1,&_fboPictureBuffer);
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT,_fboPictureBuffer);
glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT,GL_RGB,resX,resY);
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,GL_COLOR_ATTACHMENT0_EXT,GL_RENDERBUFFER_EXT,_fboPictureBuffer);

glBindFramebufferEXT(GL_FRAMEBUFFER_EXT,_fbo);

The FBO functionality works fine with all tested graphic cards. Only the stencil buffer functionality fails with above mentionned graphic cards.

Thanks for any insight.

Thank you mhagain,

The code is quite old... I now switched to ARB_framebuffer_object. I basically left everything untouched, except that I check for the availability of ARB_framebuffer_object, then bind the functions to the same names, except for the final EXT.

I have also checked that my card has EXT_packed_depth_stencil. It has it, but my problem remains on the NVidia card and Intel card. What could be the reason?

GL_DEPTH24_STENCIL8 instead of GL_DEPTH24_STENCIL8_EXT maybe ?

Anyway it seems to have some problems on ATI (http://www.opengl.org/discussion_boards/archive/index.php/t-180986.html),

interested to know to, haven't done full testing for now.

wow, fast read sorry, cool to know it works on ATI.

Thanks to both of you.

I found the problem. Changing this line:

glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,GL_DEPTH_ATTACHMENT_EXT,GL_RENDERBUFFER_EXT,_fboDepthBuffer);

into this:

glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,GL_DEPTH_STENCIL_ATTACHMENT,GL_RENDERBUFFER_EXT,_fboDepthBuffer);

Makes the trick. The question is now why it worked on ATI cards with the wrong argument?!

Hello,

The ATI card where the original (i.e. wrong) code was working was an ATI Mobility Radeon HD 5470. The behaviour was correct (i.e. the stencil buffers did what they were used for (implementation of mirrors in a scene))