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COONS PATCH


Steven Anson Coons (1912-1979): American computer engineer.

 
Given four arcs parametrized on [0,1]  such that 
The Coons patch is the surface parametrized by 
where 
and 

The Coons patch provides a method to construct a surface supported on a given contour, when the latter is composed of 4 arcs of curves.

Example:

First ruled surface parametrized by M1

Second ruled surface parametrized by M2

Bilinear patch parametrized by M3 (here, the patch is plane because the 4 vertices are coplanar, but it is a portion of hyperbolic paraboloid in the general case)

Final Coons patch M1 + M2 - M3

 
 

Production of a sphere thanks to a Coons patch


Coons patch produced by Alexandre Demir, for the prize of Meilleurs Ouvriers de France.

See also the Bezier surfaces.
 
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© Robert FERRÉOL  2017