1. Editor Modes
##Editing Modes
The editor supports both vertex and split normals, and detects which type is currently active on the selected mesh.
To switch modes, click Switch Mode in the editor panel.
- The label and icon will change to show the currently selected mode for the mesh.
- Switching from vertex to split mode preserves the selected mesh's current normals, and switching from split to vertex mode averages any normals that are split.
###Vertex
Vertex normals are stored as a direction vector for each vertex on a mesh. This mode does not allow for normal-based edge splits, so any splits will have to be part of the actual mesh.
Vertex normals reset when switching from Edit Mode or when certain operations to update the mesh data are called and do not support active modifiers present on the mesh. This mode is best used in situations that don't require switching back and forth between Blender's Object and Edit modes.
###Split
Split normals are a new addition to Blender as of version 2.74 and are stored per loop, so each polygon has an associated direction vector for each vertex it contains. This mode can only be used in Blender's Object mode and allows splitting edges.
Split normals will not reset under most conditions and support most active mesh modifiers.