This way the missing triangles would generate tetrahedrons with a very low volume and thus doesn't have a big impact on the whole volume. Just move the mesh so that the open area which is more or less flat lies next to the origin. if you should fill all the created holes and interpolate in some way the original mesh, This can be done inside meshlab, that provides some hole-filling. In case you cannot find a reliable solution to produce a watertight mesh but you are happy with an approximation of the volume there is a little trick to reduce the error. So, if your original mesh doesn't have flipped triangles then everything is fine. Since this is a reduced mesh this could have been caused by the reduction algorithm you used. So, it's important to have this fixed, too. Now I checked your example STL and this has a couple of flipped triangles which can have a big impact on the calculated volume. This means only if the mesh is watertight and doesn't have flipped triangles the value of the volume is correct. * the triangles must have correct orientation, because otherwise you may get a negative volume for a tetrahedron instead of a positive value A method for filling holes in unstructured triangular meshes with. In order to get a correct volume your object The paper presents MeshLab, an open source, extensible, mesh processing system that. Alt F to fill, then Alt J to try and remove unnecessary triangles. The volume of the whole mesh is computed by summing up the volumes of the tetrahedrons. Depending on the topology of the mesh, you could try: Grid fill ( Ctrl F > Grid fill ). Depending on which side of the triangle the origin is the volume of the tetrahedron is positive or negative, if the origin is on the side of the triangle's normal the volume is negative and positive otherwise. However, the closed holes show up as a flat black or white texture. ![]() There were some pretty significant holes that I was finally able to close and shape in Project Memento. From this tetrahedron the volume is calculated. I used Recap 360 to create a model of a cemetery tomb. Thanks a lot!!!Ĭoral1.stl (342.95 KiB) Downloaded 196 timesįirst some words about how the volume calculation works.įor each triangle you build a tetrahedron out of the triangle and the origin. So if anyone is interested here is my file (simplified to upload). Thats why I thought Freecad with the Python console would be perfect to run it automatically. ![]() I also managed to close the hole with Netfabb pretty easy but I can't click through all the files to close them manually. The problem is that I need to have the analysis run automatically (1000 files generated every 6 weeks) which I managed writing a Python skript as we have to analyse so many frags. To studz the impact these factors can have we run a long term project and analyse our corals using a 3D scanner. ![]() The impacts of global change such as raising temperatures and ocean acidification belong to the biggest threats on coral reefs. Thanks a lot for all your answers! Sorry for posting it into the wrong topic! Just a few background information: The project is designed to be my PhD thesis on global change impacts on coral growth and performance.
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