CGAL users discussion list

["Shi Yan" <>]

hello guys,


i need to implement a mesh simplification program with the quadric
error matrics.

basically this algorithm involves a lot of edge collapsing. it first
test each edge and measure the error of collapsing that edge, and pick
up all the edges with small errors as collapsing candidates, so as to
preserve the original shape of the input mesh.

suppose i've tested all the errors and picked up 1000 candidate edges
to collapse ( i pushed the candidate edges' half-edge handle into a
std::vector )

but if i collapse an edge A ,  some other candidate edges which are
also in the candidate std::vector may become invalid. for example,
collapsing edge A will destroy two adjacent triangles, and remove 2
adjacent edges.

what will happen if i collapse an invalid half-edge handle?

thank you very much.