From: Marcin Romaszewicz (marcin++at++asmodean.engr.sgi.com)
Date: 05/10/2001 11:13:51
If you leave the spot exponent at 0 and set the cutoff angle to something
less than 180, you should see a uniformly bright light that does get cut
off.
Keep in mind that spotlight cutoff is computed per vertex, so if you are
illuminating coarsely tesseletad geometry, it may appear that the entire
thing gets illuminated due to the way the interpolation works out.
-- Marcin
On Thu, 10 May 2001, John Kelso wrote:
> Hi,
>
> I'm admittedly new to Performer and OpenGL lighting, so this might a dumb
> question....
>
> I'm trying to write a little program which creates a "flashlight" in the
> scene. I've gotten the object to move around correctly and illuminate
> objects close to it, but the illumination from the flashlight spreads
> uniformly in all directions.
>
> I've tried to use the pfLightSource::setSpotCone method to set the light's
> exponent and spread, but all settings I've tried, no matter how bizarre,
> seem to have no effect on the lighting I see.
>
> Any idea what step or setting I'm leaving out? RTFM pointers welcome.
>
> Many thanks,
>
> -John
>
> -----------------------------------------------------------------------
> John Kelso www.cave.vt.edu
> Research Associate, Virginia Tech CAVE email: kelso++at++vt.edu
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> Blacksburg, VA 24061 fax: 540/231-2056
>
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