Routines
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29361: Control a policeman (2)
The address of this primary command routine is placed into bytes 8 and 9 of a policeman's buffer by the routine at 29354. It makes the policeman continue patrol duty, and chase and pick up Sam when appropriate.
Input
H 222 or 223 (policeman)
29361 CALL 63128 Exit now if the policeman is midstride
29364 CALL 31998 Is Sam wanted by the police at the moment?
29367 RRA
29368 JR NC,29476 Jump if not
29370 LD L,8 Change the address of the primary command routine in bytes 8 and 9 of the policeman's buffer to 29374 (below)
29372 LD (HL),190
This entry point is used when the policeman is not chasing Sam.
29374 CALL 63128 Exit now if the policeman is midstride
29377 CALL 31998 Is Sam wanted by the police at the moment?
29380 RRA
29381 JR C,29397 Jump if so
29383 LD L,29 Clear any disguise identifier and timeout counter in byte 29 of the policeman's buffer
29385 LD (HL),0
29387 LD L,3 Reset bit 7 of byte 3 of the policeman's buffer (no need to run if Sam's not wanted by the police)
29389 RES 7,(HL)
29391 LD L,8 Change the address of the primary command routine in bytes 8 and 9 of the policeman's buffer to 29361
29393 LD (HL),177
29395 JR 29476 Determine the policeman's next move
Sam is wanted by the police.
29397 CALL 29559 Make the policeman start chasing Sam if he spots him, or go to Sam's last known whereabouts if Sam's disguise has become known to the police
29400 JR NC,29419 Jump if the policeman is now doing either of those things
29402 LD DE,32732 32732 holds the y-coordinate of the location the police should be heading for to get Sam
29405 LD A,(DE) Pick it up in A
29406 AND A Do the police know where they should be heading to get Sam?
29407 JR Z,29476 Jump if not to make the policeman continue to go about his normal business
29409 DEC E DE=32731
29410 LD BC,3 Copy the coordinates and location identifier of the spot to which the police should be heading to get Sam into byte 10-12 of the policeman's buffer, thus making it his destination
29413 LD L,10
29415 EX DE,HL
29416 LDIR
29418 EX DE,HL
29419 LD L,3 Set bit 7 of byte 3 of the policeman's buffer (to make him run)
29421 SET 7,(HL)
29423 LD L,8 Change the address of the primary command routine in bytes 8 and 9 of the policeman's buffer to 29429 (below)
29425 LD (HL),245
29427 JR 29476
This entry point is used when the policeman is chasing Sam or heading to his last known whereabouts.
29429 CALL 31998 Should the police be chasing Sam at the moment?
29432 RRA
29433 JR NC,29374 Jump if not
29435 LD A,(32713) Collect the ID of Sam's current disguise from 32713
29438 ADD A,160 B=160-167
29440 LD B,A
29441 EX DE,HL Transfer the policeman's character number to D briefly
29442 LD C,21 Point BC at byte 21 of one of the pages 160-167, which hold the values 128, 64, 32, 16, 8, 4, 2 and 1
29444 LD HL,32744 The disguise status flags are stored at 32744
29447 LD A,(BC) Set the zero flag if Sam's disguise is unknown to the police
29448 AND (HL)
29449 EX DE,HL Transfer the policeman's character number back to H
29450 JR Z,29467 Jump if Sam's disguise is unknown to the police
29452 CALL 28942 Is the policeman close enough to Sam to pick him up?
29455 JR NC,29467 Jump if not
29457 XOR A Clear the y-coordinate of the spot to which the police should run to get Sam at 32732 (Sam has been caught)
29458 LD (32732),A
29461 LD L,29 Clear any disguise ID and timeout counter in byte 29 of the policeman's buffer
29463 LD (HL),A
29464 JP 31642 End the game if Sam has less than $46, or make the policeman pick Sam up
Sam's disguise is unknown to the police, or the policeman is not close enough to Sam to pick him up.
29467 CALL 63128 Exit now if the policeman is midstride
29470 CALL 29559 Make the policeman start chasing Sam if his disguise becomes known
29473 CALL 29052 Make the policeman switch a light on if possible
29476 CALL 60812 Determine the next move the policeman should make to reach his destination
This entry point is used by the routine at 62976 with A=1-6.
29479 CP 5 Is the character standing behind or in front of a closed door?
29481 JP NC,63100 Jump if so
29484 AND A Is the character already at his destination?
29485 JP NZ,63036 Jump if not
The policeman has reached his destination.
29488 LD L,8 Collect the LSB of the primary command routine address from byte 8 of the policeman's buffer
29490 LD A,(HL)
29491 CP 245 Is the primary command routine address 29429 (which is true if the policeman was either chasing Sam or heading towards his last known whereabouts)?
29493 JR C,29536 If not, send the policeman to a randomly chosen spot on the sidewalk or road
29495 LD DE,32732 Collect the y-coordinate of the location to which the police should run to get Sam from 32732
29498 LD A,(DE)
29499 AND A Do the police know where to run to get Sam?
29500 JR Z,29515 Jump if not
29502 LD L,2 Point HL at byte 2 of the policeman's buffer
29504 CP (HL) Compare the policeman's y-coordinate with that of the spot to which the police should run to get Sam
29505 DEC DE DE=32731
29506 JR NZ,29525 Jump unless the policeman's y-coordinate matches
29508 DEC L L=1
29509 LD A,(DE) A=x-coordinate of the spot to which the police should run to get Sam
29510 SUB (HL) Does it match the policeman's x-coordinate?
29511 JR NZ,29525 Jump if not
29513 INC E Set 32732 to 0 now that a policeman has made it to the spot to which the police should run to get Sam
29514 LD (DE),A
29515 LD L,3 Reset bit 7 of byte 3 of the policeman's buffer (to make him stop running)
29517 RES 7,(HL)
29519 LD L,8 Change the address of the primary command routine in bytes 8 and 9 of the policeman's buffer to 29374 (above)
29521 LD (HL),190
29523 JR 29536 Send the policeman to a randomly chosen spot on the sidewalk or road
29525 LD L,10 Copy the coordinates and location identifier of the spot to which the police should run to get Sam from 32731 into bytes 10-12 of the policeman's buffer, thus making it his destination
29527 LD BC,3
29530 EX DE,HL
29531 LDIR
29533 EX DE,HL Point HL back at the policeman's buffer
29534 JR 29476 Determine the policeman's next move
This entry point is used by the routine at 29354. It sets the policeman's destination to a randomly chosen spot on the sidewalk or road.
29536 CALL 61823 Get a random number in A
29539 OR 0 The operand of this OR instruction is changed by the routine at 29952: to 0 (using the event entry at 24544), or to 192 (using the event entry at 24727) to keep the policeman close to Sam's office
29541 AND 253 Discard bit 1
29543 LD E,A Copy this x-coordinate to E
29544 CALL 60165 Set the carry flag if there is no sidewalk at this x-coordinate
29547 ADC A,34 A=34 (if there is sidewalk) or 35 (if there is no sidewalk)
29549 SUB E
29550 LD D,A Copy this y-coordinate to D
29551 LD C,0 Clear bit 0 of C to indicate that the destination is not indoors
29553 CALL 29076 Set the policeman's destination to the coordinates in E, D and C
29556 JR 29476 Determine the policeman's next move
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