Andy Ross writes:

> David Megginson wrote:
>  <snip>

> Honestly, I think you might be fooling yourself on the 2D/3D
> performance issues.  There's no secret sauce in ssg that makes it
> faster; my guess is that the existing 3D cockpits are faster than the
> 2D ones because they use fewer and smaller textures, and do less
> animation of the layers.  If you were to port the 2D panels to 3D
> model files with a 1:1 mapping, you probably wouldn't see any
> difference.

My observation has been that the performance difference is very small verging on 
neglible in situations where the framerate appears to be polygon limited, but that as 
the framerate becomes fillrate limited a significant difference emerges, and that the 
difference then increases with increased pixel count.  I've seen significant 
differences at low-poly locations (KLVK, in the base package) with a high pixel 
resolution (1280 x 1024) - 30fps C172 vs. 60fps pa28-161.  This with a card that 
should comfortably fit all the textures (64M).  My gut feeling is that the 2D panels 
are probably overdrawing over scenery pixels that are also getting rendered, and that 
the 3D panels aren't, but that's a wild guess that'll probably leave me looking 
foolish when it's debunked by those who know what's going on...

Cheers - Dave

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