Hi @Gustavo_Soares_Silva
Well, the drawback of extracting the render meshes is that the objects are now meshes, so editing them isn’t as straightforward as when they are NURBS. What I usually do is just make separate layers, one with the original NURBS objects and one with the render meshes - and then turn off the NURBS layer. If editing is needed, just turn the layer back on and extract the render meshes again. That will of course grow the file size, as meshes can be quite heavy in terms of disk space, but I think it’s worth the trade-off (which is of course easy to say, when there’s 54 TB of space on the server).
Rhino (and practically all other NURBS modelers) all create render meshes, as displaying NURBS geometry directly on screen is a lot of work/slow. Every time you create/edit an object, a render mesh is created for you to see on the screen, but it exists only “on screen”. In shaded view, ghosted view etc., the NURBS isocurves and edges are superimposed on top of that mesh (and the mesh wires are hidden), so all you see is the surface in its “NURBS-form”.
Another draw back is that disjoint meshes (meshes that are joined without physically touching edges) have to have the same material and UV mapping type, which can be limiting; but for repeat geometries like roof tiles, windows, plants etc., it can really make things a lot easier to navigate.
What ExtractRenderMesh
does is simply to make that underlying mesh available to you. How precise/detailed those render meshes are is set under Tools>Options>Document Propertes>Mesh, so if you ever run into render meshes that are too coarse, changing those settings can alleviate that. There’s a couple of pages dedicated to just render meshes and their precision here and here.
For things like roof tiles (when dealing with NURBS), it might also be an idea to look into the custom render mesh settings, located in the properties panel of any given NURBS object(s).
There you can set specific render mesh settings for any object(s), so if you need fine and detailed meshes for some objects, but can settle for really coarse meshes for others, you can select a group/layer of objects and assign them their own settings, overruling the settings in Document Properties.
HTH, Jakob
PS And you can mark command names by selecting the text and clicking this </> little button (fifth button from the left) in the top of the editing window. It’s not an automatic thing, and merely makes it easier for people to identify where actual Rhino commands are mentioned and what is “just” text.