I do this in the advanced tutorial, but as I say again below, this is not the best method, though it is reliable. It will attempt to treat areas with lots of vertexes as "filled" and generate a watertight mesh. Surface Reconstruction - VCG - I only use this method with vertex splatting and only when I have a really, really dirty point set.You can be certain this mesh is 100% watertight. Surface Reconstruction - Screened Poission - The best filter in basically all mesh algorithms, this filter will take a point set (with decently correct normals, important), and attempt to create a watertight mesh out of them.You can get exactly the number of faces you desire, every time. Simplification - Clustering Edge Collapse Decimation - By far the best way to simplify the number of faces in your model.Keep in mind it generates a lot of faces beneath the mesh surface that makes the mesh not "watertight" Create Solid Wireframe - Great for our purposes, as it will turn thin walls into prisms.Useful for filling in empty areas by selecting the geometry you'd like to fill. Convex Hull - Forms a sort of bounding box of your mesh, but with another mesh that is purely convex.Close Holes - This can be useful for when you are doing VCG with vertex splatting, as it can fill some missing geomtry.CSG Operation - Used to combine two or more meshes, typically I am doing unions.Remeshing, Simplification, and Reconstruction face num) - Useful for deleting small blobs that aren't a part of the mesh you are trying to capture. Select by vertex quality - Used in conjunction with ambient occlusion to delete geometry below the surface.Delete selected Faces and Verticies - Exactly what it says.These are organized by filter section below: Selection I highly reccomend you either save temporary files or use "Filters->show current filter script" to recreate what you've done to this point. Meshlab has no undo button, so be prepared to reload your meshes and do the workflow again to that point. I'll give a brief rundown of using them later in this tutorial, as these are super time savers. mlx scripts, and if you have a workflow that you are using for a group of meshes (like for a mod), then I highly reccomend using these scripts. Meshlab filters can be 100% scripted with. Meshlab works on all platforms, even web nowdays, but I fully reccomend using your platform specific version, as processing time is much faster, and meshlab will even use GPU when available. Meshlab is great for taking 3D scanned point clouds and generating meshes from them. Point Clouds are simply a collection of points, but often these have color, texture, and normals in addition to position. Often, though, we don't start with nice triangle meshes and either are given point-clouds or have to convert to point clouds and then back into triangle meshes. A mesh is a bunch of triangles, and is often the end goal of any 3D graphics. Meshlab (and meshes in general) work on three basic concepts: verticies (points), edges, and faces (triangles). So I will do my best to give understandable plain english descriptions of the various pieces of meshlab. These papers describe the various filters and settings in meshlab in much better detail than I ever could, but also are written in standard "academic speak" (un-readable). Nearly everything in the project is based on published papers in academia. Meshlab is an open source project that is almost more of an academic tool than an industry tool. What I will be covering in this tutorial is the various filters, the meshlab basics, and tips/tricks I have found most useful for doing mesh work and leave the art part of watertight meshwork to you. Instead, mesh work often rhymes and is both and art and a science. I have successfully made watertight meshes out of all sorts of different projects over the years using the tool, and basically there is no one-way to solve any given mesh or set of points. I am no expert in meshlab, nor in mesh manipulation.
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