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I use Euler's formula to compute the genus number. https://math.stackexchange.com/questions/85163/finding-the-topological-genus-of-a-triangulated-surface Because my triangle mesh is not closed, the genus number should be 1. But I have meshes with genus number greater than 1. Is there any software that can highlight handles? I hope to remove the handles, but have little experience to do it. Can anyone can provide some links or papers about it?

In fact, I use one 3D scanner to scan one object and obtain one triangle mesh. The resultant mesh has no holes, is not closed and the object doesn't has any handle. So I expect genus number should be 1. However the genus number is larger than 1. I think I should do something to fix it. I load the mesh into MeshLab, but the mesh looks normal. I　hope to identify the handles using some software if such software exist.

Thanks in advance. Regards Jogging

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Jogging Song
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  • Are u sure that your mesh is watertight? – Ahmed Matar Mar 27 '14 at 16:36
  • Why the mesh need to be watertight? If the mesh is watertight, the genus should be 0. If not, the boundary loops should be considered. Now I find handles on the mesh and hope to remove it. Currently I am reading two papers: Topological Noise Removal and An Efficient Computation of Handle and Tunnel Loops via Reeb Graphs. – Jogging Song Mar 28 '14 at 01:20
  • genus has nothing to do with the mesh being watertight, there is a big difference between genus holes and actual holes like missing face or something http://upload.wikimedia.org/wikipedia/commons/thumb/f/f0/Triple_torus_illustration.png/100px-Triple_torus_illustration.png this mesh is watertight and yet it has genus of 3, if yor mesh has actual holes http://b.vimeocdn.com/ts/378/519/378519074_640.jpg like this one it will mess with your genus count – Ahmed Matar Mar 28 '14 at 11:36
  • Thanks. I think I understand the difference between holes and handles. After the holes are filled, the handles are present on the mesh. I hope to remove handles. What's the name of the software from the second link? Is it an open source software? – Jogging Song Mar 29 '14 at 15:09
  • It is called [Rhino](http://www.rhino3d.com/) and it is not free – Ahmed Matar Mar 30 '14 at 09:25

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http://research.microsoft.com/en-us/um/people/hoppe/proj/isotoposimp/

I might be six months too late, but I was looking into an area that is related to meshes and came across your post. The link above is the research I know for identifying (and removing!) handles in meshes, perfectly suited for your needs.

Tawnos
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