Add mesh utilities nodes

[gregoire-dl]

Description

Add two nodes for mesh boolean operations and mesh conversion.

Features list

• Add MergeMeshes node
• Add ConvertMesh node

See alicevision/AliceVision#969

[natowi]

This part should be added to the MergeMeshes documentation/(probably too much for the description field):

Operation types used to merge two meshes:

• boolean_union: Create a new mesh with the combined volume of the two input meshes.
• boolean_intersection: Create a new mesh from the intersected volumes of the two input meshes.
• boolean_difference: Create a new mesh from the volume of the first input mesh subtracted by the second input mesh.

[flobotics]

hi,
i tried it, but did not work ? Also is there a way to output .obj also, now it seemed to output .stl only ?

After which node should the mergeMeshes node be added, after texturing?

The error in the log-view is like:

o-[DelaunyTetgen] Warning constraints have 4 edges on the border
Error: Encounterd a problem ,relaunch in diagnose mode
Error: Found 27 facets with intersections
o-[Booleans] Error could not tetrahedralize operand B

Then it saves an empty .stl file.

--I tried boolean-union option--

Or do i need to add e.g. 3-5 pictures from the first mesh into the "build"-process of the second textured-mesh and after that, mergeMesh A with mesh B ? So that the second mesh "knows" something ( compares camera alignment, position, etc. of these 3-5 camera-poses of second-mesh, to the camera alignment, position,etc. of the 3-5-camera-poses in the first mesh ) of the first mesh ?

thx for help