Returns true if the other is less than half the size of myself

Clamps the given velocity vector so that it can't be more than N degrees above the horizontal. This is done so that it is easier to leverage the maxim

Clip the coordinates of a point, p, against a box. The result, q, is the closest point to p that is inside the box.

UseOriginalIndices: should the output mesh use same vertex indices as the original point cloud. If this is false, then we generate a new vertex buffer

https://computergraphics.stackexchange.com/questions/1736/vr-and-frustum-culling

https://manialabs.wordpress.com/2012/08/06/covariance-matrices-with-a-practical-example/ http://www.cse.psu.edu/~rtc12/CSE586Spring2010/lectures/pcaLe

Sample points along a parabolic curve until the supplied mesh has been hit. p0 - starting point of parabola v0 - initial parabola velocity acc

Mark a face as disabled and return a pointer to the points that were on the positive of it.

Returns true if the caller should reset the path tracer accumulation buffer.