topological reconstruction of triangular meshes

Dickinson, John John.Dickinson at
Wed Jan 19 16:38:07 PST 2000

I am also looking for algorithms or even code that reconstruct topological
information from a list of triangles.  I mean tha I have a list of triangles
with their surface normal and 3 vertex points specified in 3-space like:

normal (nx,ny,nz) vextices 1:(x,y,z) 2:(x,y,z) 3:(x,y,z)
normal (nx,ny,nz) vextices 1:(x,y,z) 2:(x,y,z) 3:(x,y,z)

and I want to create two lists:
1: (x,y,z)
2: (x,y,z)
3: (x,y,z)
4: (x,y,z)

1: use vertices 1,3,5
2: use vertices 2,4,5


Note that the vertex coordinates "should" match in the data input but some
loss of precision is often encountered leading to difficulties in matching
vertices from different triangles together.

-((Insert standard disclaimer here))-|- Washington Irving (1783-1859) -
John Kenneth Dickinson               |   "A sharp tongue is the only
Research Council Officer  IMTI-NRC   |    edge tool that grows keener
email: john.dickinson at         |    with constant use."

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