Re: [info-performer] transforming an objects world coordinates into pixels

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From: DANIEL BASS (BASSD++at++aaicorp.com)
Date: 05/09/2003 08:31:07

It sounds like you want to draw the cross-hair as a 2-d object in
screen space over the 3-d scene. Here is an alternative. Make
the cross-hair a billboard with a mostly transparent texture (except
the hairs) . Then each frame, calculate the line-of-sight from the
viewpoint to the 3-d object. Place the x-hair billboard along that
l-o-s at just beyond the near-plane distance (just make sure that
you draw the billboard last!)

--daniel

>>> Tone Milazzo <tone1971++at++yahoo.com> 05/08/03 07:17PM >>>
In brief: I want to draw a cross hair over an object thats in a 3d
setting. And I want to keep the cross hairs over the object while the
pfchannel moves around. I can do all the geometry by hand but is there
a
method in pfChannel that'll take a pfDCS and return the screen X & Y?

TIA
-tone

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