Field Name             Bits   Default Description
PVS_NUM_SLOTS          3:0    0x0     Specifies the number of vertex slots to be used in the
                                      VAP PVS process. A slot represents a single vertex
                                      storage location1 across multiple engines (one vertex per
                                      engine). By decreasing the number of slots, there is more
                                      memory for each vertex, but less parallel processing.
                                      Similarly, by increasing the number of slots, there is less
                                      memory per vertex but more vertices being processed in
                                      parallel.
PVS_NUM_CNTLRS         7:4    0x0     Specifies the maximum number of controllers to be
                                      processing in parallel. In general should be set to max
                                      value of TBD. Can be changed for performance analysis.
PVS_NUM_FPUS           11:8   0x0     Specifies the number of Floating Point Units
                                      (Vector/Math Engines) to use when processing vertices.
VAP_NO_RENDER          17     0x0     If set, VAP will not process any draw commands (i.e.
                                      writes to VAP_VF_CNTL, the INDX and DATAPORT
                                      and Immediate mode writes are ignored.
VF_MAX_VTX_NUM         21:18  0x9     This field controls the number of vertices that the vertex
                                      fetcher manages for the TCL and Setup Vertex Storage
                                      memories (and therefore the number of vertices that can
                                      be re-used). This value should be set to 12 for most
                                      operation, This number may be modified for
                                      performance evaluation. The value is the maximum
                                      vertex number used which is one less than the number of
                                      vertices (i.e. a 12 means 13 vertices will be used)
DX_CLIP_SPACE_DEF      22     0x0     Clip space is defined as:
                                      0: -W < X < W, -W < Y < W, -W < Z < W (OpenGL Definition)
                                      1: -W < X < W, -W < Y < W, 0 < Z < W (DirectX Definition)
TCL_STATE_OPTIMIZATION 23     0x0     If set, enables the TCL state optimization, and the new
                                      state is used only if there is a change in TCL state,
                                      between VF_CNTL (triggers)
