Routines
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59343: Spawn Tracked Enemy Entities
Used by the routine at Evaluate_And_Spawn_Tracked_Enemies.
Initialises the tracked-enemy active count at 50221 to zero, copies the per-wave count byte into 50220 and adds it to the total wave enemy count at Active_Enemy_Count, then stashes the wave data pointer. If the count is zero, jumps to Spawn_Tracked_Enemy_Entities_Terminate; otherwise loops B times: writes a 14-byte entity record (handler Process_Tracked_Enemy_Entity, entity type 176 random type variant, random screen position via Pick_Random_Spawn_Position_Y, three initial bytes from the wave data for velocity seeds, and 255 as the terminator) into the entity list via *Entity_List_Write_Pointer, spawning each entity via Draw_Wide_Entity_Sprite. Closes the entity list with the 53668 terminator.
Spawn_Tracked_Enemy_Entities 59343 XOR A Clear 50221 copy the spawn count into 50220 and accumulate it into the wave enemy count at Active_Enemy_Count.
59344 LD (50221),A
59347 LD A,(HL)
59348 LD (50220),A
59351 PUSH AF
59352 LD B,A Stash the wave data pointer, load the entity list write pointer, and jump to Spawn_Tracked_Enemy_Entities_Terminate if the count is zero.
59353 LD A,(50204)
59356 ADD A,B
59357 LD (50204),A
59360 POP AF
59361 INC HL
59362 AND A
59363 PUSH HL
59364 LD HL,(50441)
This entry point is used by the routine at 36963.
Spawn_Tracked_Enemy_Entities_0 59367 JP Z,Spawn_Tracked_Enemy_Entities_Terminate
59370 LD B,A
Spawn_Tracked_Enemy_Entities_Record 59371 PUSH BC Write the Process_Tracked_Enemy_Entity handler and entity type 176 to the entity list record.
59372 LD DE,58208
59375 LD (HL),E
59376 INC HL
59377 LD (HL),D
59378 INC HL
59379 LD (HL),176
59381 INC HL
59382 LD (HL),4 Generate a random entity type variant via Generate_Random_Byte.
59384 INC HL
59385 CALL Generate_Random_Byte Mask to 2 bits for the type variant and add 40.
59388 AND 3
59390 ADD A,40
59392 LD (HL),A Write the entity type variant and advance.
59393 INC HL
59394 PUSH HL Point HL at the spawn buffer, write the type variant, and call Pick_Random_Spawn_Position_Y to generate a valid random screen position.
59395 LD HL,50449
59398 LD (HL),A
59399 INC HL
59400 CALL Pick_Random_Spawn_Position_Y
59403 LD DE,50491
59406 LDD Copy three bytes from the wave data at 50491 using LDD×4 and apply the direction delta via Apply_Direction_Delta.
59408 LDD
59410 LDD
59412 PUSH HL
59413 LDD
59415 LD A,(HL)
59416 LD (DE),A
59417 EX DE,HL
59418 CALL Apply_Direction_Delta
59421 EXX Set colour INK: RED, PAPER: BLACK (BRIGHT) in B' and spawn the entity via Draw_Wide_Entity_Sprite.
59422 LD B,66
59424 EXX
59425 CALL Draw_Wide_Entity_Sprite
59428 POP HL Write three velocity seed bytes, initial deltas, and the 255 record terminator; loop back to Spawn_Tracked_Enemy_Entities_Record for the next entity.
59429 POP DE
59430 XOR A
59431 LDI
59433 LD (DE),A
59434 INC DE
59435 LDI
59437 LD (DE),A
59438 INC DE
59439 PUSH DE
59440 CALL Advance_RNG_Seed
59443 LD DE,0
59446 CALL Clamp_Entity_Velocity
59449 POP DE
59450 EX DE,HL
59451 LD (HL),D
59452 INC HL
59453 LD (HL),E
59454 INC HL
59455 PUSH HL
59456 CALL Advance_RNG_Seed
59459 LD DE,0
59462 CALL Clamp_Entity_Velocity
59465 POP DE
59466 EX DE,HL
59467 LD (HL),D
59468 INC HL
59469 LD (HL),E
59470 INC HL
59471 LD (HL),255
59473 INC HL
59474 POP BC
59475 DJNZ Spawn_Tracked_Enemy_Entities_Record
Spawn_Tracked_Enemy_Entities_Terminate 59477 LD DE,53668 Save the entity list pointer to *Entity_List_Write_Pointer and write the 53668 terminator.
59480 LD (50441),HL
59483 LD (HL),E
59484 INC HL
59485 LD (HL),D Write 255 and advance HL.
59486 INC HL
59487 LD (HL),255 Restore the wave data pointer and return.
59489 POP HL
59490 RET
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