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MrDoomMaster

OpenGL OpenGL Evaluators

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MrDoomMaster    103
I'm having a bit of difficulty understanding glMap2f. I want to create a roof to a hangar, which is simply a plane bent in one direction. I want to make this roof using evaluators. In the glMap2f function, I do not understand the u, v, stride, and order parameters. I also have no idea how the array is to be structured. In fact, I really can't tell you much about evaluators in general. If someone could explain these parameters for me, I would greatly appreciate it. I would like to be able to visualize how a nurb surface is drawn using evaluators. I know that the surface is composed of X number of lines in each direction, suppose 8 lines horizontal and 8 lines vertical (a bit like a grid). Can someone explain the order at which these are drawn, and how they're drawn? Just so everyone knows, I've already read the Nurbs and Evaluators section in the OpenGL red book. Absolutely no help. It is a bit too "technical" for me I suppose. I need something simple... Thanks.

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MrDoomMaster    103
Quote:
Original post by njpaul
Try this. I haven't read through the whole thing myself so I can't vouch for how good it is.


Thank you very much, this is exactly the help I needed.

You've been rated! Take care!

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