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View Full Version : [OT] NVIDIA Forceware 71.84 + VBO MapBuffer + GLSL = Access Violation?



dpoon
03-04-2005, 03:01 AM
Hi all,

Sorry if this might be OT.

I've been using the 71.84 betas posted on the NVIDIA site with my GLSL app. My font engine uses a single VBO that is updated each frame using glMapBuffer(). Each frame the app renders the scene using GLSL shaders. Then it performs the font rendering using fixed function alpha-blending. I'm getting an access violation error when rendering the font. However it worked fine with the 66.93 drivers.

Has anyone been experiencing similar problems? Or is it just my app :confused:

yooyo
03-04-2005, 04:23 AM
If you use wglUseFont.... calls to create font it internally compile each character in display list. Im not sure how did they do it, but they use vertex arrays and glDrawElements or glDrawArrays call.

Problem is when you use VBO with vertices and indices stored in GPU memory, you have to:



glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_NORMAL_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
glBindBuffer( GL_ELEMENT_ARRAY_BUFFER_ARB, 0 );
glBindBuffer( GL_ARRAY_BUFFER_ARB, 0 );before font rendering.

Seems that mixing regular vertex arrays in display list and vbo produce this issue.

I don't know is it bug or feature...

yooyo