Re: Cosmo3D/Optimizer: Screen size of shape

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Angus Dorbie (dorbie++at++sgi.com)
Mon, 20 Apr 1998 09:55:37 -0700

Mike Krus wrote:
>
> Hi,
>
> I am currently trying the access the screen size of the bounding box of
> a cosmo3D csGeometry object. The csDrawAction provides access to the
> transformation and to the camera (and thus to the camera
> transformation).
>
> Given the bounding box of a csGeometry how do I use the two
> transformation
> matrices to compute the size of that bb on the screen?
>

Well if it doesn't cross the hither plane you could just transform
the corners through the modelling then projection matrix and scale
to window coordinates then use min max testing for bounds. If it does
cross then clip the edges to produce new transformable points.

Cheers,Angus.

-- 
"Only the mediocre are always at their best." -- Jean Giraudoux 


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