[ODE] Rendering Bottlenecks

[Robert Rose]

On Tuesday, June 1, 2004, at 11:50  AM, John Rieffel wrote:
>
> I'm comparing ODE on two machines:
>
> - a 1GHz Athlon running RedHat 6.1
> - a 867 MHz G4 (12" Powerbook) running Mac OS 10.3.4
>
> When rendering using the drawstuff libraries, I'm a little bit suprised
> that the G4 framerates are significantly higher than the Athlon's.  
> Could this possibly be because of hardware openGL rendering on the G4?

The G4 has 128 bit floating point SIMD instructions, while the Athlon 
probably doesn't have float point SIMD instructions, only integer.  I'd 
need to look this up... I know Intel didn't add floating point SIMD 
until the PIII (and it wasn't any good until the P4), I dunno about 
AMD.  That could be a major difference, depending upon how your 
compiler is generating code.

You could also be compiling ODE in single precision on the Mac and 
double precision on the PC, that would make a difference.

I know the 12" Powerbook has a great OpenGL chip in it.  What's in your 
Athlon?  If it's doing OpenGL in software that could be it right there.

-robert