petsc-3.14.6 2021-03-30

DMPlexComputeProjection3Dto2D

Rewrite coordinates of 3 or more coplanar 3D points to a common 2D basis for the plane. The normal is defined by positive orientation of the first 3 points.

Synopsis

#include "petscdmplex.h"   
#include "petscfe.h"       
PetscErrorCode DMPlexComputeProjection3Dto2D(PetscInt coordSize, PetscScalar coords[], PetscReal R[])

Not collective

Input Parameter

	coordSize	- Length of coordinate array (3x number of points); must be at least 9 (3 points)
	coords	- The interlaced coordinates of each coplanar 3D point

Output Parameters

	coords	- The first 2*coordSize/3 entries contain interlaced 2D points, with the rest undefined
	R	- 3x3 row-major rotation matrix whose columns are the tangent basis [t1, t2, n]. Multiplying by R^T transforms from original frame to tangent frame.

Level

developer

Location