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marce
07-21-2009, 07:10 AM
What is exactly the difference between calling a command in a display list and calling a function (or method in Java) that calls the OpenGL command?

Is it faster to call it from a display list?

Dark Photon
07-21-2009, 08:46 AM
What is exactly the difference between calling a command in a display list and calling a function (or method in Java) that calls the OpenGL command?

Is it faster to call it from a display list?

Think of display lists to OpenGL the way you think of a C++ compiler to C++ code.

This is like calling OpenGL directly:

cc -o exec src.cxx
exec
cc -o exec src.cxx
exec
cc -o exec src.cxx
exec
...

and this is like calling it indirectly via a display list:

cc -o exec src.cxx
exec
exec
exec
exec

V-man
07-21-2009, 10:29 PM
It depends on the command. If you have vertices, normals, texcoords, the driver can generate a VBO which would be faster for rendering.
For all other GL commands, no, it won't be faster.

marce
07-22-2009, 03:30 AM
Ah, ok! Thanks for your answers. It made it more clear.