Re: Shadows (Yet Another Object Graphics Question)

[davidf(at)dfanning.com (David Fanning)]

Jason P. Meyers (jpm7934@cis.rit.edu) writes:

> 	I learned my lesson with the Orb/sphere thing.  Before, I try to do
> things the hard way, I'll pose the question and see what surfaces.
> 
> Does IDL support casting shadows caused by one object onto another, for
> example a ball over a ground plane?  Here is what I am doing:
> 
> 1) I created two spheres (using the orb object)
> 2) I place them in 3-D space according to some user specified params
> 3) I "tether" them to the origin with a polyline
> 4) I display some axes (centered on [0,0,0])
> 5) I create a white ground plane just under the x & y axes (i.e. z=-0.1)
> 6) I place it all in an IDLexObjView object (I love being lazy!)
> 7) I display it in a draw widget
> 
> This all works nicely.  However, I would like to see a projection (i.e.
> shadows) of the spheres (and tethers too) in the ground plane.
> 
> If I can't do this, my current idea is to draw two more lines and a pair
> of
> circles on the ground plane.  I have all the data necessary to do this. 
> But
> if something line MyView->TurnOnShadows exists, I would be all for using
> that!
> 
> As always, I am open to any suggestions and thank you in advance.

Oh, oh. He just got WAY beyond my meager knowledge
of objects.

Cheers,

David

P.S. Let's just say I wish I were young again. For
a *lot* of reasons. :-(

-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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