Subdivision generates a smoother, higher resolution mesh which is based on the geometry of the base mesh, and updates when you make changes to the base mesh. This allows you to construct and edit a high resolution model without having to deal with all of its geometry directly. To get a quick idea of what subdivision does, create a cube or some other shape and then press C one or two times to Subdivide. Try selecting and moving some of its faces, and you will see that even though the cube has been subdivided into a refined spherical shape, you are still actually working with the geometry of the original cube. Press V to Unsubdivide again. If you want to export or work with the high resolution mesh directly, you will need to Refine it, which will make the current subdivision level the new base mesh. The exception to this is Displacement Painting, which uses brush-like tools to manipulate the underlying mesh at any subdivision level without needing to refine it. No file type currently supports the transfer of subdivision or displacement information directly between applications, although an object can be subdivided again with similar results in applications which support subdivision. Displacement data can be exported via a Normal Map.
- Subdivide creates a smoothed version of an object underlying the original object. Edits applied to the original polygon mesh will affect the subdivided shape. This operation can be performed multiple times to create a smoother underlying shape. You can use the Paint Displacement tool to displace the smooth subdivided surface using brush tools.
- If an object has been subdivided, Unsubdivide goes back one level of subdivision. This can be performed until there is no underlying subdivided shape.
Refine Control Mesh: Shift + C
- Refine Control Mesh deletes the polygonal control mesh and makes the underlying subdivided shape at the current subdivision level directly editable.
- Crease Edges makes the subdivided shape more closely conform to the control mesh along the creased edges. Creased edges cannot be exported to other applications, unless you refine the control mesh.
- Uncrease Edges removes creases (if applied) from the selected edges.
Subdivision in Silo can be used to preview how a rendered model will look.
- Subdivision behaves unexpectedly with non-manifold geometry (e.g. where more than two faces share a single edge). If you see "spikes" in your mesh when subdividing, this is most likely the cause. This is not a bug.