5.2.2.2 Tone Routines

  Input Coordinates Content of Processing
SZxxTU U Rotation/Normalization transformation, Linear interpolation
SZxxTT T Map projection, Great circle interpolation, Clipping at map boundaries
SZxxTV V Clipping in viewport
SZxxTP V Projection transformation, Switching between soft/hard fill
SZxxTR R Clipping in WS viewport
SZxxTZ R WS transformation, buffering
SZxxTS V Buffering (soft fill)
SZTNSV V Soft fill


These routines can be considered as expansions of the interface routine SZTNZc(N,PX,PY). The following is a program for producing a tone using the basic routines.


   CALL SZTNOP(ITPAT)

     CALL SZOPTc

       CALL SZSTTc(UXX,UYY)

        .......

     CALL SZCLTc

   CALL SZTNCL

SZTNOP changes the tone pattern, performs processing concerning the direction of the boundary lines, and inquires the necessary information using SGRGET, so frequent calls will affect speed.