It is defined by four vertices , , and . The orientation of a tetrahedron is the orientation of its four vertices. That means it is positive when is on the positive side of the plane defined by , and .
The tetrahedron itself splits the space in a positive and a negative side.
The boundary of a tetrahedron splits the space in two open regions, a bounded one and an unbounded one.
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introduces a tetrahedron t with vertices , , and .
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Test for equality: two tetrahedra t and t2 are equal, iff t and t2 have the same orientation and their sets (not sequences) of vertices are equal. | ||
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Test for inequality. | ||
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| returns the i'th vertex modulo 4 of t. |
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returns vertex(int i). |
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| Tetrahedron t is degenerate, if the vertices are coplanar. |
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Precondition: : t is not degenerate. | ||
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Precondition: : t is not degenerate. |
For convenience we provide the following boolean functions:
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| returns the signed volume of t. |
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| returns a bounding box containing t. |
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returns the tetrahedron obtained by applying on the three vertices of t. |