You probably turned on lighting but don't have any lights in the world.

Either add a light with [world_light] or [light] or turn lighting off by sending a message lighting 0 to the gemwin.

You can also send a reset message to gemwin to set it back to the startup state (which doesn't have any lighting).

If you are using 'view' in your patch to change the viewpoint, you may not be pointing in the correct direction. You also might have translated everything outside of the current viewport. Also, if you have been using single buffering ('buffer 1' message to gemwin), then you might still be in that mode. Either send a 'buffer 2' message or a 'reset' message to gemwin. Then, destroy and create your window.

there are several ways:

• on W32
  • ?? most likely you can set this with a driver-specific application
• OSX
  • use the FSAA message to [gemwin]. the value specifies the number of multisamples used for anti-aliasing (AGL_SAMPLES_ARB)
• linux
  • nvidia
    • you can use the FSAA message to [gemwin]. the exact values you should pass to FSAA are depending on your hardware and your driver. see the driver documentation for valid (and good) values.
    • use nvidia-settings (to eventually override the "FSAA" message)
  • ati/radeon
    • use ati-config
    • instally Catalyst from ATI and use the control center
  • other cards
    • see driver documentation