Selecting Colored Areas of a Mesh


Hi everyone

I created a mesh of an underwater object (coral) and want to select only that part of the mesh that is part of the object (living coral) and not the underground (seabed). When I explode the mesh into various smaller meshes, it is often the case that those small meshes consist of part-object (coral) /part-underground (seabed). To only get the object I want, I can split the meshes manually by using “delete mesh faces” and then use “split disjoint meshes” - yet this is quite a lot of work and I am looking for a more simple solution. I added a picture for clarification.

Could I select the object I want (living coral) through for example colour or through texture? Or through the creation of a silhouette? Or any other suggestions?

Thank you all!

(Kyle Houchens) #2

your best bet would be to extract the faces of the coral, and then join them into a new separate mesh. In the example above, you’d have three meshes, two coral and the sea floor.

use the ExtractMeshFaces command to split the coral parts off. then join the extracted faces (if necessary) do the same for the other coral, and you’d get three separate meshes.


Thanks @theoutside ! That is indeed another option to do it. Yet, it does still take a lot of time as I would need to click on a lot of individual mesh faces and I am looking for a quicker method. Would you know whether it is possible to select mesh faces by colour, or by texture?

Thanks again :slight_smile:

(Kyle Houchens) #4

Afaik, you can’t select by color, however you can spilt by curve. Draw a curve around where you want a separation, then split the mesh into as many parts as necessary. If this fails, you can extrude the curve into a nurbs surface and then do a mesh Boolean split using the nurbs surface and the mesh Boolean split tool.

Kyle Houchens
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Thank you very much! I tried the split by curve and that works really well! Exactly what I was looking for.

All the best


As a separate idea since I’ve done similar with mesh scans. I find Extractmeshface with SelBrush to be a speedy and satisfying way to do this. Selbrush with deletemeshface will also work. Theoutside’s method should work really well for a mesh that’s you can seperate off by modeling the cut but might be computationally intensive on a really dense mesh.