A default map doesn't define any geometric properties. Instead, it uses the following five methods for defining the material space coordinates:
Surface - The target surface defines the material space. This is a useful method when creating waving flags and skin textures, where the texture must stretch with the surface.
|Some surfaces do not define valid UV coordinates along the surface.|
Identity - This method uses the rendering space coordinates. Because the rendering space is tied to the camera, this alternative is suitable only for still images.
Null - No material space computations at all. The material space remains as possibly defined by the previous material mapping objects. A quick mapping method for materials that do not contain any patterns, such as glass.
Camera - Uses the current camera orientation to project material properties to target objects. A point under the top left corner of the image has coordinates (0,0,distance), the bottom right corner (1,1,distance).
Custom - Moves a selected channel to the 'Map coords' channel. This is a suitable mapping type when you want to parametrize a material with a user channel that has been added as a 'vertex variable' to a SDS or NURBS object.