Decimated meshes

Questions about Anatomist manipulation

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alexis
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Decimated meshes

Post by alexis »

Good evening,

I'm currently facing a problem when viewing decimated meshes. I'm using a process based on a matlab script itself based on the reducePatch function to reduce withe meshes from the AnaDoAll pipeline.
Everything works well except when I use a decimation rate between 0.25 and 0.3 (I've got nearly 22000 vertices at first ) . If I do this, the mesh is calculated, anatomist (3) can load it, but when I put it in a window, all the system is freezed, and the only solution I have is to brutally shut down the computer.
It's maybe linked to my video card, an ATI FireGL V3100, as this problem doesn't occur on other computers with Nvidia cards. But I find very strange that it works for rates 0.1 , 0.2 , 0.24 , 0.31 , 0.4 , 0.5 etc ... and not for 2.5 , 2.6 , ... , and 3.
Any idea will be welcomed !
Bye
Alexis Barbot
CNRS UPR640 LENA
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Yann Cointepas
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Post by Yann Cointepas »

You should check that your mesh is correct. If the 3D driver is bugged, it could fail to display triangles with 0 length vertices for example. Have you checked the decimation of several meshes ?
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alexis
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Post by alexis »

Hi,

yes I tried with several meshes, and my conlusion is that the problem always occurs when meshes are between ~5500 and ~6700 vertices ... Whatever the initial meshes are.
The most funny is that if I have a 22000 vertices mesh, wich I decimate with a 0.5 rate, I can see it, and if I iterate the operation on the decimated mesh with again a 0.5 rate, I can't see it.
I'll try to update my drivers, but I did it not so long ago ...
What do you mean when you speak of "triangles with 0 length vertices" ? Do you mean a triangle based on a same point for two vertices ... ? or is it in the vertices coordinates ?
Alexis Barbot
CNRS UPR640 LENA
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Yann Cointepas
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Post by Yann Cointepas »

Well both same point and same coordinate can lead to a kind of division by zero problem. It is just an idea, I don't know where the problem comes from.
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