# Objective
When merging two meshes, we need to find the offset of indices for the
second mesh. Currently it is done by inserting empty positions if
positions is not set.
Although practically it is not an issue, this does not feel right:
- We did not have positions before, then why we have positions after
merge?
- Moreover, if positions are not set, but uvs are not empty, computed
offset will be zero, while it should be equal to the number of uvs.
## Solution
Use `Mesh::count_vertices` to find the number of vertices.
## Testing
Looking hard.