SUBROUTINE PERSPC(X,Y,Z,XT,YT)
      LOGICAL JUMP
      COMMON/CSETOR/JUMP,EX,EY,EZ,AX,AY,AZ,D,R,COSBE,COSAL,COSGA
      XLESEX=X-EX
      YLESEY=Y-EY
      ZLESEZ=Z-EZ
      Q=D/(XLESEX*COSAL+YLESEY*COSBE+ZLESEZ*COSGA)
      IF(JUMP) GOTO 30
      XT=((EX+Q*XLESEX-AX)*COSBE-(EY+Q*YLESEY-AY)*COSAL)*R
      YT=(EZ+Q*ZLESEZ-AZ)*R
      RETURN
 30   XT=((EZ+Q*ZLESEZ-AZ)*COSAL-(EX+Q*XLESEX-AX)*COSGA)*R
      YT=(EY+Q*YLESEY-AY)*R
      RETURN
      END