Routines
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55444: Handler: Moving Objects
Used by the routine at Dispatch_Handlers.
Animates the 19-byte records at *ReferenceMovingObjects.
Walk the moving-object list.
Handler_MovingObjects 55444 LD IX,(25642) Point IX at the moving-object list.
Skip inactive objects and expired timers.
Handler_MovingObjects_Loop 55448 LD A,(IX+0) Jump to Handler_MovingObjects_Done if the terminator 255 is reached.
55451 CP 255
55453 JR Z,Handler_MovingObjects_Done Jump to Handler_MovingObjects_Next if this object is inactive.
55455 BIT 7,A
55457 JR NZ,Handler_MovingObjects_Next Deactivate the object if its timer is zero.
55459 XOR A
55460 CP (IX+1)
55463 JR NZ,Handler_MovingObjects_Draw
55465 SET 7,(IX+0) Jump to Handler_MovingObjects_Next.
55469 JR Handler_MovingObjects_Next
Set the font and clip window.
Handler_MovingObjects_Draw 55471 LD HL,31856 Use Buffer_ActiveFont, or Graphics_TileFont when the stored font ID differs.
55474 CP (IX+18)
55477 JR Z,Handler_MovingObjects_Font
55479 LD HL,36976
Handler_MovingObjects_Font 55482 LD (23606),HL Write HL to *CHARS.
55485 LD C,(IX+16) Write the object's clip window to *ClipWindow.
55488 LD B,(IX+17)
55491 LD (25625),BC
55495 CALL JumpTable_AdvanceEntity Call JumpTable_AdvanceEntity.
Test the moving edge against the stored limit.
55498 LD A,(IX+9) Compare the moving edge against the stored limit.
55501 OR A
55502 LD A,B
55503 JR NZ,Handler_MovingObjects_LimitHit
55505 LD A,C Jump to Handler_MovingObjects_Update if they differ.
Handler_MovingObjects_LimitHit 55506 CP (IX+14)
55509 JR NZ,Handler_MovingObjects_Update
Reverse at the stored limit.
55511 CALL Reverse_Direction Call Reverse_Direction.
55514 LD A,(IX+14) Swap the two limit bytes.
55517 LD B,(IX+15)
55520 LD (IX+15),A
55523 LD (IX+14),B
55526 CALL JumpTable_AdvanceEntity Call JumpTable_AdvanceEntity.
Store, move, draw and erase the object.
Handler_MovingObjects_Update 55529 CALL JumpTable_StorePosition Call JumpTable_StorePosition.
55532 CALL JumpTable_MoveEntity Call JumpTable_MoveEntity.
55535 CALL JumpTable_DrawEntity Call JumpTable_DrawEntity.
55538 CALL JumpTable_EraseEntity Call JumpTable_EraseEntity.
Advance to the next moving object.
Handler_MovingObjects_Next 55541 LD DE,19 IX+=0019.
55544 ADD IX,DE
55546 JR Handler_MovingObjects_Loop Jump to Handler_MovingObjects_Loop.
Restore the default clip window.
Handler_MovingObjects_Done 55548 LD BC,536 Write 536 to *ClipWindow.
55551 LD (25625),BC
55555 RET Return.
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