Godot Version
Godot 4.7.1 on Linux Fedora
Question
Hello; is there a way to tell Godot : hey buddy, this is a mesh, use the same data for it , occlusion shape and collision shape …
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For collisions you can select the MeshInstance3D node, press the Mesh button at the top of the 3D viewport and select Create Collision Shape...
For occluders you add an OccluderInstance3D node, select that node and press the Bake occluders button at the top of the 3D viewport.