000 JOB ENTER PLOT POINTS FROM 1407 CTL 4411 * * This is a revision of a routine by Jack Bresenham * or * by Van Snyder . The changes to Jack's * routine are in lower case. * ORG 501 * * TRAVEL SUBROUTINE * TRAVEL SBR LEAVE&3 ZA ZEROA,ALPHA ZA XTRGT,DELX ZA YTRGT,DELY S XPR,DELX S YPR,DELY MCW XTRGT,XPR MCW YTRGT,YPR ZA DELX,DELA ZA DELY,DELB MZ *&8,DELA NEED MAGNITUDE SO A B BITS MZ *&1,DELB * DETERMINE OCTANT C DELA,DELB BM DELXN,DELX BM DELYN,DELY MN PXPY,D45 BH D00PY D00PX MN PX,D00 SETDEL ZS DELA,DEL A DELA DELA NOW DOUBLED-SEE DRIVING LOOP A DELB NOW DOUBLED-SEE DRIVING LOOP B TALPHA DELXN BM DELXYN,DELY MN NXPY,D45 BH D00PY D00NX MN NX,D00 B SETDEL DELYN MN PXNY,D45 BL D00PX D00NY MN NY,D00 B DELAY D00PY MN PY,D00 DELAY MN DELY,DELA DELA S/B DELY SAVE PLUS MCW MN DELX,DELB DELB S/B DELX MCW B SETDEL DELXYN MN NXNY,D45 BL D00NX B D00NY * PLOTTER DRIVING LOOP D00GO MCW %T0,D00,S MOVE RELATIVE ZERO DEGREES TALPHA C ALPHA,DELA leave be * * dummy A TWOA,ALPHA NOTE DELA HAS BEEN DOUBLED A DELB,DEL NOTE DELB PREVIOUSLY DOUBLED BM D00GO,DEL MCW %T0,D45,S S DELA,DEL NOTE DELA PREVIOUSLY DOUBLED B TALPHA * CONSTANTS ALPHA DCW #6 YTRGT DCW #6 DESIRED Y COORDINATE XTRGT DCW #6 DESIRED X COORDINATE DELY DCW #6 Y2 MINUS Y1 DELX DCW #6 X2 MINUS X1 YPR DCW #6 PRESENT Y COORDINATE XPR DCW #6 PRESENT X COORDINATE DELB DCW #6 DEPENDENT VARIABLE DIFF DELA DCW #6 INDEPENDENT VARIABLE DIFF DEL DCW #6 DECISION DIFFERENCE D00 DA 1X1,G RELATIVE 0 DEGREE MOVE D45 DA 1X1,G RELATIVE 45 DEGREE MOVE PX DCW @3@ 0 DEGREE CODE PXPY DCW @2@ 45 DEGREE CODE PY DCW @1@ 90 DEGREE CODE NXPY DCW @8@ 135 DEGREE CODE NX DCW @7@ 180 DEGREE CODE NXNY DCW @6@ 225 DEGREE CODE NY DCW @5@ 270 DEGREE CODE PXNY DCW @4@ 315 DEGREE CODE ZEROA DCW &0 TWOA DCW &2 * * END OF TRAVEL SUBROUTINE * * --CALLING SEQUENCE-- * 1. ZA DESIRED X COORDINATE, XTRGT * 2. ZA DESIRED Y COORDINATE, YTRGT * 3. B TRAVEL * * XPR,YPR ARE UPDATED * TRAVEL EXECUTED * CONTROL RETURNED TO INSTR AFTER *B TRAVEL* x3 equ 99 BEGINX LCA MXGX,47 SW 27,MSGX-1 MCE XPR,33 sbr place&6,xtrgt type lca gmwm,48 MCW %T0,21,W CS 8 lca gmwm,8 wait bin vin,q b wait VIN MCW %T0,1,R sbr x3 BIN TYPE,* bce noplac,1,} BM VMINUS,1 mcw za,place BWZ VPLUS,1,B SW 1 place za 15998&x3,* noplac bw beginy,msgx-1 B TRAVEL B BEGINX vminus mcw zs,place VPLUS SW 2 B PLACE beginy lca msgx,47 mn y,47 mn y,21 convert msgx to msgy SW 27 CW MXGX-1 MCE YPR,33 sbr place&6,ytrgt B TYPE * CONSTANTS gmwm dcw @}@ group mark with word mark MSGX DCW @X NOW 0 -, ENTER NEXT X@ y dcw @y@ za za zs zs END BEGINX