On Friday 28 January 2005 02:18, Curtis L. Olson wrote:
> Tiago Gusmão wrote:
> > Altough the billboard itself always faces the POV, you can still set
> > the normal the way the real light would be pointing to, them set a
> > diffuse light on the POV and enable backface culling.
> > I suppose performance hit should be minimal for TnL hardware.
> The normal only affects lighting. Backface culling is done based on the
> "winding" of the triangle. You would still see the light from every
What about setting only one point at the beginning of the runway
and then calculating an angel between it and the normal of the billboard.
When the angel is > 90° or > - 90° the billboard is turned off when it is <
90° or < -90° then on.
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