maximum control points for evaluators (mesh)

am drawing a mesh using glMap2f. is there a limit to the number of control points that can be defined ?

the program displays the mesh for 8*8 number of control points , but it does not show the mesh if i use more control points. what am i doing wrong ?

I think you can get the maximum number of controlpoints your implementation supports with glGetInteger and GL_MAX_EVAL_ORDER. It seems to me that your implementation doesn’t support more than 8 control points.

hi Bob,
Thanks for ur reply. it helped i found that the max eval order on our Linux machine is 8 and the max eval order on sgi workstation is 30. what factor determines the eval order ? is there a way to improve it ?

The limit is set by whoever writes your OpenGL implementation, and you cannot improve this number. Well, you can of course change implementation, but that generally means you also have to change graphics hardware.