3d graphics

[Daniel Monteiro Basso]

On Mon, 2007-06-04 at 19:15 +0200, NoiseEHC wrote:
> The problem with 3d graphics as I see is memory bandwidth. Filling 
> 1200x900 even if only just one color component in every pixel is a 
> no-no. The only option is to render to an overlay surface and scale that 
> to the display.

That's exactly what I did.

First of all, let me introduce myself. I work on the development team
at LEC-UFRGS in Porto Alegre, Brazil, where we're investigating the
pedagogical aspects of the laptop use.

I adapted the code from TinyGL (by Fabrice Bellard) to be used with the
XVideo extension, and got some good results. The "gears" test app runs
at 50fps rendering to a 256x256 framebuffer (that is later scaled to
fullscreen through xv). The rendering code makes costless to switch
resolutions on-the-fly, so it can be adjusted as the scene load changes.

I'm using a XO-B2, so I stumbled upon the RV16 scale bug [1] (XO versions <
B3) that makes the image quality severely affected.

I don't have time to describe it further right now, so later I'll send
another e-mail with more information.

Daniel

[1] http://dev.laptop.org/ticket/336