How do I copy the vertices, edges, and faces of one mesh into another?

Question

I have a handful of mesh objects and I'd like to display one of them per frame. Thus far, I've been switching out entire mesh objects like this:

myObject.data = meshes[frame_number]

Unfortunately, the object's shader is tied to each mesh, so when I change the mesh, the shader disappears.

I know that I can use myMesh.from_pydata() to edit the actual mesh, but I'm not quite sure how to get the vertices, edges, and faces out of a mesh and copy them into another. I tried this, but got an error:

#gives an error:
myMesh.from_pydata(otherMesh.vertices, otherMesh.edges, otherMesh.polygons)

Any ideas on how I can swap meshes but retain the object's shader?

Answer 1

One way is, as you are doing, Swapping the mesh

ob1.data = mesh # assign mesh to ob1
ob1.data = mesh.copy() # assign a copy of the mesh to ob1

how to use another meshes verts, edges and polygons to pass to the mesh.from_pydata method.

cone = context.object # some other object
mymesh = bpy.data.meshes.new("mymesh")
vertices = [v.co for v in cone.data.vertices]
faces = [[v for v in p.vertices] for p in cone.data.polygons]
# let faces take care of edges
mymesh.from_pydata(vertices=vertices, edges=[], faces=faces)
# could make edges
edges = [[v for v in e.vertices] for e in cone.data.edges]

Using from_pydata isn't going to fix the shader issue.