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arXiv · 1603.07500

Recognizing projections of rational curves

Juan Gerardo Alcázar·Carlos Hermoso
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Abstract

Given two rational, properly parametrized space curves ${\mathcal C}_1$ and ${\mathcal C}_2$, where $\CCC_2$ is contained in some plane $\Pi$, we provide an algorithm to check whether or not there exist perspective or parallel projections mapping $\CCC_1$ onto $\CCC_2$, i.e. to recognize $\CCC_2$ as the projection of $\CCC_1$. In the affirmative case, the algorithm provides the eye point(s) of the perspective transformation(s), or the direction(s) of the parallel projection(s). The problem is mainly discussed from a symbolic point of view, but an approximate algorithm is also included.

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Juan Gerardo Alcázar, Carlos Hermoso. 2016-03-24. Recognizing projections of rational curves. https://arxiv.org/abs/1603.07500

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