[Gmsh] Bug in test_move_point_parametric_triangle

[Peter Wainwright]

Amazingly, I have discovered a potentially serious bug in the routines
which perform edge collapse in the BDS_Mesh.

Owing to this, it is possible for a point to collapse onto a linear
boundary creating slivers (triangles with collinear points).

The problem is that the sides of the triangle, a and b, are not
recalculated after the point is moved.  Thus, area_final and area_init
are always equal!  So the test for slivers is defeated.

I attach a simple patch to fix this.

That aside, gmsh works great for me. Many thanks for this program!

Peter Wainwright


-------------- next part --------------
A non-text attachment was scrubbed...
Name: gmsh-2.3.0-collapse.patch
Type: text/x-patch
Size: 565 bytes
Desc: not available
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20090115/81b28a5a/attachment.patch>