>   Hi,
> 
>     I'm looking for information on realtime deformation algorithims.
>   What I'd like to do is have some 3-D object like a sphere composed
>   of polygonal faces and be able to interactively prod the sphere
>   and see it deform proportionally to the applied force.
> 
>     Has anyone out there done anything similiar to this, or know of
>   any good articles that might address this problem ?  I'd even be
>   intested in 2-D versions of this problem (i.e. deformation of a
>   series of connected line segments).  Please respond by internet
>   mail if possible and I'll summarize the responses if there is enough
>   interest.
> 
> 
>   Steve Berger (sb@onripx.neuro.emory.edu)


I know a simple algorythm, i already use to perform 3D objects transformations :

Use two array ( or equivalent) : 
	- the first one contains the source point ( in 2D or in 3D ) - named S -
	- the second one contains the destination coordinates - named D -

Then use one ( or two or tree coef ) - named co1 co2 co3 ( from 0 to .. 1 ) -
	and display all points like that :

	    x = S.x[ii] * co1  +  ( D.x[ii] * ( 1 - co1 );
	    y = S.y[ii] * co2  +  ( D.y[ii] * ( 1 - co2 );
	    z = S.z ..... co3 ....... z ........... co3

	And then increment co1, co2, co3 ( step .001 ) for example.

It's not very efficient but it's a great idea to start ... No ?


				Bye ... all your comments will be welcome

-- 
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JOLY Thomas
University of PARIS VII ( Jussieu )
Licence Informatique
mail : joly@amertume.ufr-info-p7.ibp.fr
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