Defines bit patterns that enable user-defined clipping planes. These macros are defined as a convenience when setting values for the D3DRS_CLIPPLANEENABLE render state.
This macro has no parameters.
This macro does not return a value.
User-defined clipping planes are enabled when the value set in the D3DRS_CLIPPLANEENABLE render state contains one or more set bits (that is, is not 0). The value of the render-state is not important; the system does not interpret the value as a number. Rather, the value enables the clipping plane whose corresponding bit is set. Bit 0 controls the state of the first clipping plane (at index 0), bit 1 the second plane, and so on.
The bit patterns that these macros create can be combined by using a logical OR operation to simultaneously enable multiple clipping planes. Omitting one of these macros from the combination effectively disables the clipping plane at that index.