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Conic Representations for Shape Description
April 1987 (vol. 7 no. 4)
pp. 23-30
Peter Wilson, General Electric Company
The question of what is the "best" form of geometry for use in CAD systems and for data exchange between systems has often been argued with much intuition but few facts. I will present here some numerical stability results for several formulations of conic curves with the conclusion that the point/vector/scalar representation performs best. This also leads to a form of referential geometry that has significant advantages for use in geometric modeling systems.

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Peter Wilson, "Conic Representations for Shape Description," IEEE Computer Graphics and Applications, vol. 7, no. 4, pp. 23-30, April 1987, doi:10.1109/MCG.1987.276868
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