COMMENT ⊗   VALID 00002 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	BEGIN "PICNET"
C00005 ENDMK
C⊗;
BEGIN "PICNET"
REQUIRE "DDSUB.SAI[GRA,HPM]" SOURCE_FILE;
INTEGER PORTS,ROWS,LEVELS;
INTEGER I,J,K,L,M,C;

DDINIT;
WHILE TRUE DO
 BEGIN
 OUTSTR("PORTS:"); PORTS←CVD(INCHWL);
 OUTSTR("LEVELS:"); LEVELS←CVD(INCHWL);
 ROWS←PORTS↑(LEVELS-1);

 OUTSTR("DD CHAN "&CVS(C←GDDCHN(-1))&'15&'12); 
 SCREEN(-.1*LEVELS,-.1*ROWS,1.1*LEVELS,1.1*ROWS);
 DRKEN; RECTAN(-1000,-1000,1000,1000);

 LITEN;
 FOR K←0 STEP 1 UNTIL LEVELS-1 DO FOR I←0 STEP 1 UNTIL ROWS-1 DO
  RECTAN(K+5/12,I+1/8,K+7/12,I+7/8);
 FOR I←1,2,3 DO DPYUP(C); SHOW(C);
  
 FOR I←0 STEP 1 UNTIL ROWS-1 DO
 FOR J←0 STEP 1 UNTIL PORTS-1 DO
  BEGIN
  RECTAN(0,I+(J+1/3)/PORTS,1/6,I+(J+2/3)/PORTS);
  LINE(1/6,I+(J+1/2)/PORTS,5/12,I+1/8+6/8*(J+1)/(PORTS+1));
  RECTAN(LEVELS-1/6,I+(J+1/3)/PORTS,LEVELS,I+(J+2/3)/PORTS);
  LINE(LEVELS-1/6,I+(J+1/2)/PORTS,LEVELS-1+7/12,I+1/8+6/8*(J+1)/(PORTS+1));
  END;
 FOR I←1,2,3 DO DPYUP(C);

 FOR K←0 STEP 1 UNTIL LEVELS-2 DO
 FOR I←0 STEP 1 UNTIL ROWS-1 DO
 FOR J←0 STEP 1 UNTIL PORTS-1 DO
  BEGIN
  INTEGER II,JJ,KK,SUB,IMSUB;

  SUB←ROWS%PORTS↑K;
  IMSUB←I MOD SUB;
  KK←K+1;
  II←(J*SUB+IMSUB)%PORTS+I-IMSUB;
  JJ←IMSUB MOD PORTS;

  LINE(K+7/12,I+1/8+6/8*(J+1)/(PORTS+1),
      KK+5/12,II+1/8+6/8*(JJ+1)/(PORTS+1));
  DPYUP(C);
  END;

        IF (INCHRW LAND '137)="X" THEN
           BEGIN
           SHOWA(-1);
           OUTSTR(" xgping ... "&'15&'12);
           XGPUP(-4);
           END;
        CLRBUF; SHOW(-1); RDDCHN(C);
 END;

END;