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nik_bg
06-23-2004, 10:23 PM
I have a model of e.g. 200,000 triangles. Instead of using naive glNormal() and glVertex() call for each vertex, how much performance improvement can be expected if I use glVertexPoinetEXT() and glNormalPointerEXT() extensions? Or any other more performance-useful extensions/ideas?

Thank you.

ce110ut
06-24-2004, 06:51 AM
why not test and share your results with us?

that would be greatly appreciated, especially for those of us who have yet to try but have also wondered.

:regards:

Aeluned
06-24-2004, 06:58 AM
You can expect *huge* performance gains. Why don't you do it and see for yourself?

harsman
06-26-2004, 08:31 AM
As a side note, vertex arrays have been core since OpenGL 1.1 which is fairly ancient. No need for the EXT unless you're running on some old sgi box or something.

Rados
06-26-2004, 12:15 PM
If you have a very big mesh, use Vertex Buffer Objects. You will gain a huge boost in speed.
You can find an example of how to use VBOs on NeHe.gamedev.net

06-26-2004, 05:51 PM
If you use VBO, the the Lock extension is of no use, right? Or does it still help speed things up?

Because from what I understand, the Lock extension keeps your vertices and triangle data in video memory until you unlock them which speeds all your glDrawElements calls up a lot. But using VBO, your data is already in video memory, so would using the Lock not really do anything?

harsman
06-27-2004, 02:14 AM
Yes, compiled vertex arrays are pointless with VBOs. VBOs are tighter speced as well and should offer greater performance than CVAs.