Use vertex path on one mesh to cut a hole in another mesh

Question

I am attempting to prepare a mesh for an acoustic simulation that requires a maximum edge of 4mm, with 1mm resolution at the ears.

The original mesh is @ 1mm res.

I'm aware of two techniques:

1. ReMesh

2. Sculpting with Simplify brush (and dynamic topology enabled)

   I've tried both out.

   My favourite is ReMesh, as it lets me precisely control the upper edge length:

But I require the ears to be at a higher density!

So, I duplicate, and remesh the duplicate to low resolution. Now I want to put the ears of the original onto the head of the Lo-Res.

Now I'm stuck, what next?

It would be wonderful if I could just use this path to cut the original mesh.

Maybe if I select the entire ear, and extrude slightly into the head and slightly out of the head, then I could perform Boolean operations using this extruded ear.

So I could do LoRes-mesh MINUS extruded-ear + original-mesh INTERSECT extruded-ear

I have to say, I don't like the sound of this.

How about Knife Project, using the vertex path?

Answer 1

Got it!

<3 Blender :]

I did it using the Knife Project tool:

1. Load full resolution mesh
2. Duplicate to 'LoRes', hide the original, select the duplicate
3. Remesh to a low resolution
4. Edit Mode
5. Create a vertex path around ear using CTRL+Click
6. Copy these into a new 'cutpath' object: 3dView ToolShelf -> Duplicate (click twice) 3DViewMenu->Mesh->Vertices->Separate->Selection
7. Object Mode -> Select 'cutpath', SHIFT+Select 'LoRes'
8. Edit Mode -> Knife Project
9. Circle Select to select bits of the ear that got missed out
   10. x to Delete verts

OK, now I have the LoRes mesh with the ear cutout. Now I just have to use the same 'cutpath' to cut the ear from the original mesh, and stick it in.