format  void SPR_3Initial (Spr3WorkArea * workArea)
 Input  workArea: Work area definition table
 Output  None
 Function value  None
 Function  VDP1 3D display is initialized.
 
 
 The viewpoint is the origin of the world coordinate system and the viewpoint angle is (0,0,0) (Z positive direction)
Are set in the order X → Y → Z.
 Light source angle is (0,0,0) (positive direction of Z).
 The clipping level is 2, and the maximum / minimum display range of the viewpoint coordinate system Z coordinate is -0.005
To the negative minimum. 

  format  void SPR_3SetClipLevel (Uint16 clipLevel, Fixed32 clipZmin,
 Fixed32 clipZmax)
 Input  clipLevel: Clipping level number
  0 = No clipping
  1 ​​= clip in Z range of viewpoint coordinate system (after coordinate conversion)
.  2 = Delete polygons that do not appear on the screen (after perspective transformation)
:  3 = Clip at frame buffer boundary (after perspective transformation)
  clipZmin: Minimum value of viewpoint coordinate system Z coordinate clip
:  clipZmax: Maximum value of the viewpoint coordinate system Z coordinate clip
 Output  None
 Function value  None
 Function  Sets the polygon clipping level. Higher level has lower level functions
Includes  . For level 1, clipping in the viewpoint coordinate system with the maximum Z coordinate value of the polygon
 Do , but set the range with clipZmin and clipZmax before executing SPR3_DrawModel ()
  needs to be determined.