David Megginson writes:
> 
> Norman Vine wrote:
> 
> > My not so WAG is that the newer code draws MUCH less then the old approach.  
> > i.e. All of the 2D Panel was drawn as was all of the scenery that it obscured. 
> > In the new approach SSG is clipping those instruments not seen and the occluded 
> > scenery is not drawn.  Note this includes the scenery occluded by the rest of the 
> > planes interior too
> 
> We're talking about using the old (2D) panel animation code inside a 3D 
> cockpit, where the panel itself is a 3D object behind the instruments.  The 
> amount of scenery visible in the 3D scene graph is exactly identical (take a 
> look at the default 172p, which uses the old 2D panel code).

Ah... OK but keep in mind you are still drawing all of the Panel even if it is not 
all in view,  this includes all of the 'state changes' taking place in the 2D code 
that 
aren't necessarily happening in the 3D code and SSG might also be smart enough 
to optimize some of these 'state changes' to no-ops or at least minimal-ops. 
AFAIK the 2D code doesn't do any 'OpenGL state' optimization.

Andy's approach for making a true SSG Text object is IMHO the probably the 
way to go about this.  Another approach is to render the texture object each 
frame but this is probably to slow on older cards

Norman

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