[Celestia-developers] Mesh rendering changes

[Chris L. <cl...@ww...>]

I just checked in several fixes for mesh rendering.  I made a couple
corrections to depth bucket coalescing that fix problems reported with
rthorvald's Ran add-on.  In addition to being a beautiful add-on, it
really stresses Celestia's use of the z-buffer.  Objects aren't always 
drawn perfectly, but overall the situation is much better than in 1.3.1.
The other change to mesh rendering should just affect performance.  
Celestia will now use the ARB_vertex_buffer_object OpenGL extension for 
meshes.  On my system, I saw Celestia's frame rate jump from 28 to 85 
frames per second when rendering the cmod version of jestr's million 
polygon Immense class starship 
(http://www.shatters.net/~claurel/celestia/cmodtools/immense-cmod.zip).  
85 fps is my refresh rate, so that's not even the true performance cap.
As usual, this has only been tested on NVIDIA hardware.  It should work on 
ATI hardware, but there were problems with this extension when I tried to 
use it for spheres.  I'd really appreciate some further testing.  I 
compiled a 1.3.2pre11 EXE for this purpose:
http://www.shatters.net/celestia/files/celestia-win32-1.3.2pre11-exe.zip

--Chris