PDA

View Full Version : Two simple questions, answer please.



Andru
08-26-2002, 04:35 AM
Hi, I'm playing with a kind of particle system thingy... and have a few questions:

1. What is the fastest way of drawing thousands of *small* triangles (about pixel size or a little bigger). Display lists ? Or just straight glBegin(GL_TRIANGLES) stuff ?

2. Is there "billboarding" in OpenGL ??

Thanks in advance,

// Andru

nexusone
08-26-2002, 07:06 AM
1. Display list are faster then using a bunch of glbegin/glend's, but if the triangle is the size of a pixel, you are not going to be able to tell it is a triangle.
Then make a display list of points instead.

2. Yes you can do billboarding in opengl. Billboarding is not a function, but a style of drawing objects to reduce polygon count.


Originally posted by Andru:
Hi, I'm playing with a kind of particle system thingy... and have a few questions:

1. What is the fastest way of drawing thousands of *small* triangles (about pixel size or a little bigger). Display lists ? Or just straight glBegin(GL_TRIANGLES) stuff ?

2. Is there "billboarding" in OpenGL ??

Thanks in advance,

// Andru



[This message has been edited by nexusone (edited 08-26-2002).]

Arath
08-26-2002, 07:22 AM
1. display list but if data may change (like position or vertex color) use vertex array (CVA, VAR, etc ...)

2. yes check this http://www.lighthouse3d.com/opengl/billboarding/

Arath