High Order Surface Render States
There are three render states that are used with high order surfaces. These render states are described below.
This render state is used to control whether patch edges use discrete or continuous tessellation. See the DirectX 8.0 SDK documentation for more details.
This render state gives the number of segments to be used for each edge of the patch. If an explicit number of segments is specified in the DP2 token those segments should override the value of this render state. For more details, see the DirectX 8.0 SDK documentation.
This render state notifies the driver that a patch is to be deleted. For more information, see D3DRENDERSTATETYPE.