EvaluatePosition in vtkQuadraticQuad incorrect
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
vtkQuadraticQuad.cxx (Version 5.4 – 6.2, most likely ever since this class was introduced).
In line 87/88:
static int LinearQuads[4][4] = { {0, 4, 8, 7}, {8, 4, 1, 5}, {8, 5, 2, 6}, {7, 8, 6, 3} };
should be rather
static int LinearQuads[4][4] = { {0, 4, 8, 7}, {4, 1, 5, 8}, {8, 5, 2, 6}, {7, 8, 6, 3} };
This array is used to split the quadratic quad into 4 linear quads, evaluate the position in these 4 linear quads and then calculate the parametric position within the quadratic quad.
But the code for doing the latter works only, when the second linear quad is defined as in the corrected version above.