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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 M _{1} |
Second ruled surface parametrized by M _{2} |
Bilinear patch parametrized by M _{3} (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 M _{1 }+ M_{2 }- M_{3} |

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