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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Another slight adjustment of the two tetrahedra gives an intersection consisting entirely of interlocking triangles as handled by the algorithm described in the previous post, except for one case where two edges of one triangle pierce another. This intersection therefore must be solved by a combined algorithm.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">The solution in the image is correct in the sense that if we cut loose the corner of the green tetrahedron inside the red tetrahedron along the white cutting arc, turn it inside out, and glue it to the red tetrahedron along the cutting arc, the result is a solid that is exactly the green tetrahedron subtracted from the red tetrahedron, an honest to goodness constructive boolean operation.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Even though the result is correct, the algorithm is not yet correct. In two places where it made the wrong decisions I just plugged in the right decisions as magic numbers. There is still some unknown amount of work ahead of me to make it come up with the correct decisions on its own. Still, it looks pretty cool, no? This is one of those algorithms where shortly after becoming functional on a few simple test cases it will most likely just work on meshes of arbitrary size and complexity.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Regards,</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Daniel</p>
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