From: Jan Dvorak <jan.dvorak@...>
Date: 2008-04-19T06:04:49+09:00
Subject: Re: Ruby Opengl Speed

On Thursday 17 April 2008 02:08:16 Diego Bernardes wrote:
> Yea, this is what i want to know, thanks Jan :)
> I already made some 2d games in ruby using gosu and now im going to 3d
> Just another question, i'm dont know opengl already, i'm just starting
> my studies, you said "offload anything on GPU", how can this offload can
> be done?
>
> There is a Gears demo made in ruby with opengl comparing with c, it uses
> display lists, so get almost the same speed of c, this is what you say
> about "offload anything on GPU"?

Yes, display lists and vertex arrays/VBO for static objects are good start, 
but you can do any general per-vertex or per-pixel processing on GPU via 
shaders. Common example in games is skeletal-bone animation done in vertex 
shader (a.k.a. hardware skinning) where you send only mesh's base pose in 
array/VBO and bone matrices as uniform variables or attributes and the shader 
computes the desired pose. 

Jan