Bernard Leclerc (bleclerc++at++cae.ca)
Thu, 18 Jul 1996 15:08:43 -0400
> I'm working on a Performer project and I'd like to make
> a nice transition between one scene and another, where
> the screen gets brighter each frame until it is completely
> white, and then darkens again to reveal the new scene.
Jeremy,
There's been a discussion recently on light/exposure control using either a
semi-transparent polygon or the accumulation buffer.
I've retained the idea of using a semi-transparent polygon drawn after the
scene is rendered. I suggest you use a channel draw callback to change the
projection to ortho (pfChannel::makeOrtho) and then draw the semi-transparent
white polygon (pfGeoSet::draw). The level of transparency will give you the
whiteness you're looking for. This trick's been used to implement a camera fade
in/fade out.
Using the accumulation buffer also works fine but is more expensive than
drawing an extra polygon.
--
Bernard Leclerc CAE Electronics Ltd., 8585 Cote De Liesse
Technical Leader Saint-Laurent, Quebec, Canada, H4L-4X4
3-D Graphics Applications tel: +1 514 341 2000 extension 2275
bleclerc++at++cae.ca fax: +1 514 340 5496
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