FSAA

OpenGL OpenGL: Advanced Coding
1

I have questions regarding GL_multisample:

  1. How do I know what the supported max number of samples is before initialising the display surface?

  2. My graphics card (NV8800GT) supports 16x samples, if I force this via the NV control panel, I get regular multisampled results at 8x and 16x samples in my program. Performance is good.

If I pass ‘8’ as the number of samples in my program (multisample extension), the rendered images are multisampled at 8x, identical to the nv control panel option set to ‘8’. No discernable performance change compared to the NV control panel method. No problem there.

However, when I set the samples at ‘16’ in my program, the image is supersampled instead (for example, textures and alphatested surfaces seem to be 2x sampled) and performance is much lower than setting 16x in the NV control panel.

What’s the deal with this?

2

  1. glGetIntegerv(GL_MAX_SAMPLES_EXT, &samples)

  2. Try http://opengl.org/registry/specs/NV/framebuffer_multisample_coverage.txt with 16 coverage samples and 8 colour samples

3

Thank you, I will have a look at that. :slight_smile: