Routines
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40337: Handler: Flame
Handles a flame (sprite IDs 52-55) which has been started by SpawnFlame. A flame which is not in the player's room is counted off by ExpireActor. In the player's room it burns for a limited time, drifting around in a random direction (which is changed by ChooseFlameDirection whenever its timer runs out or it is blocked) and bouncing off the edges of the screen. It flickers by changing sprite and colour every time it is handled, and it plays a crackling sound. If it touches the player (while the player is coloured INK:WHITE, PAPER:BLACK (BRIGHT)) the player is hit. When its time is up, or the player is dead, the flame is blown up.
Input
IX Flame record
Count off the flame if it is not in the same room as the player.
HandlerFlame 40337 LD A,(38659) Fetch the room of the player from 38659.
40340 CP (IX+1) Jump to ExpireActor if the flame is in a different room to the player.
40343 JP NZ,ExpireActor
40346 LD A,23 Write 23 to Actor_Width (the width of the flame).
40348 LD (38573),A
40351 CALL StoreEntity Remember the previous position of the flame.
Explode the flame if the player is not alive.
40354 LD A,(38658) Fetch the sprite ID of the player.
40357 SUB 16 Subtract 16 (the first Sabreman sprite ID).
40359 CP 32 Jump to BlowUpActor if the player is not alive.
40361 JP NC,BlowUpActor
Explode the flame when its lifetime runs out.
40364 DEC (IX+8) Decrease the lifetime of the flame by one and jump to BlowUpFlame if it has run out.
40367 JP Z,BlowUpFlame
Choose a new direction when the direction timer has run out.
40370 DEC (IX+2) Decrease the direction timer by one and choose a new direction if it has run out.
40373 CALL Z,ChooseFlameDirection
Work out the new position of the flame and bounce off the edges of the screen.
40376 CALL CalculateNewPosition Work out the new position of the flame.
40379 BIT 0,B Jump to BounceFlameHorizontally if the flame has hit the left or right edge of the screen.
40381 JR NZ,BounceFlameHorizontally
40383 BIT 1,B Jump to BounceFlameVertically if the flame has hit the top or bottom edge of the screen.
40385 JR NZ,BounceFlameVertically
This entry point is used by the routines at BounceFlameHorizontally and BounceFlameVertically.
Stop the flame moving through objects in the room. If it did not manage to move then choose a new direction.
HandlerFlame_Move 40387 LD BC,5903 Set the height of the flame in B to 23 and the width in C to 15.
40390 CALL SlideActorPastObjects Stop the flame passing through objects in the room.
40393 CALL TestPositionUnchanged Test whether the flame has stayed where it was.
40396 CALL Z,ChooseFlameDirection Choose a new direction if the flame has stayed where it was.
Flicker the flame by choosing one of the four flame sprites and a colour at random.
40399 LD A,(38549) Fetch the random seed from RandomNumber.
40402 AND %00000011 Keep only bits 0-1.
40404 OR %00110100 Set bits 2, 4-5.
40406 LD (IX+0),A Set the sprite ID of the flame.
40409 CALL ChooseFlameColour Choose a colour for the flame.
40412 LD (IX+5),A Set the colour of the flame.
Store the new position.
40415 LD (IX+3),E Set the X position of the flame.
40418 LD (IX+4),D Set the Y position of the flame.
Hit the player if the flame touches the player, but only if the player is coloured INK:WHITE, PAPER:BLACK (BRIGHT).
40421 LD A,(38663) Fetch the colour of the player from 38663.
40424 CP 71 Jump to HandlerFlame_Draw if the player is not coloured INK:WHITE, PAPER:BLACK (BRIGHT).
40426 JR NZ,HandlerFlame_Draw
40428 LD BC,4879 Set the height of the flame in B to 19 and the width in C to 15.
40431 CALL TestPlayerTouchingActor Test whether the flame is touching the player.
40434 JR NC,HandlerFlame_Draw Jump to HandlerFlame_Draw if the flame is not touching the player.
40436 LD A,(38661) Fetch the X position of the player from 38661.
40439 RLCA Rotate bit 7 (which half of the screen the player is in) into bit 0.
40440 AND %00000001 Keep only bit 0.
40442 INC A Add one, so the hit direction is 1 or 2.
40443 LD (38660),A Store the hit direction in 38660 (the player's state).
Draw the flame and make the crackling sound.
HandlerFlame_Draw 40446 CALL DisplayActor Display the flame.
40449 JP PlayFlameSound Jump to PlayFlameSound to play the flame sound.
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