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objects.asm
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1691 lines (1340 loc) · 36.1 KB
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TYPE_PLAYER = 1
TYPE_SMOKE = 2
TYPE_DISK = 3
TYPE_EXPLOSION = 4
;sprite number constant
SPRITE_BASE = SPRITE_DATA / 64
SPRITE_BALL = SPRITE_BASE + 0
SPRITE_SMOKE = SPRITE_BASE + 3
SPRITE_DISK = SPRITE_DATA_BLUE_DISK / 64
SPRITE_EXPLOSION = SPRITE_BASE + 3 + 5 * 4
;offset from calculated char pos to true sprite pos
SPRITE_CENTER_OFFSET_X = 8
SPRITE_CENTER_OFFSET_Y = 1;11
;------------------------------------------------------------
;check joystick (player control)
;------------------------------------------------------------
!zone BHPlayer
BHPlayer
lda #0
sta PLAYER_AFFECTED
lda JOY_VALUE
and #$10
bne .NotFire
jsr .HandlePlayer
;did we die?
lda PLAYER_KILLED
beq +
.Killed
rts
+
.NotFire
.HandlePlayer
lda SPRITE_CHAR_POS_X_DELTA,x
ora SPRITE_CHAR_POS_Y_DELTA,x
bne .NoJoy
lda PLAYER_DIR
beq .HandleLRMove
lda JOY_VALUE
and #$01
bne .NotUp
lda #1
sta SPRITE_DIRECTION_Y,x
jmp .NoJoy
.NotUp
lda JOY_VALUE
and #$02
bne .NotDown
lda #2
sta SPRITE_DIRECTION_Y,x
jmp .NoJoy
.HandleLRMove
lda JOY_VALUE
and #$04
bne .NotLeft
lda #2
sta SPRITE_DIRECTION,x
jmp .NoJoy
.NotLeft
lda JOY_VALUE
and #$08
bne .NotRight
lda #1
sta SPRITE_DIRECTION,x
jmp .NoJoy
.NotDown
.NotRight
.NoJoy
.YMovement
;y movement
lda SPRITE_DIRECTION_Y,x
beq .NoYMovement
cmp #2
beq .GoDown
jsr ObjectMoveUpBlocking
bne .Moved
jmp .BlockedY
.GoDown
jsr ObjectMoveDownBlocking
bne .Moved
.BlockedY
lda PLAYER_AFFECTED
bne .Killed
;blocked, toggle dir (1<>2)
lda #3
eor SPRITE_DIRECTION_Y,x
sta SPRITE_DIRECTION_Y,x
jmp .YMovement
.Moved
;for vertical mode
lda PLAYER_DIR
beq +
;if we moved in y, reached full char pos again?
lda SPRITE_DIRECTION_Y,x
beq +
lda SPRITE_CHAR_POS_Y_DELTA,x
bne +
;yes!
lda #0
sta SPRITE_DIRECTION_Y,x
+
.NoYMovement
;x movement?
lda SPRITE_DIRECTION,x
beq .MovedX
cmp #1
beq .GoRight
.GoLeft
jsr ObjectMoveLeftBlocking
bne .MovedX
;blocked, auto-bounce right
lda PLAYER_AFFECTED
lbne .Killed
lda #1
sta SPRITE_DIRECTION,x
jmp .GoRight
.GoRight
jsr ObjectMoveRightBlocking
bne .MovedX
;blocked, auto-bounce left
lda PLAYER_AFFECTED
lbne .Killed
lda #2
sta SPRITE_DIRECTION,x
jmp .GoLeft
.MovedX
;for vertical mode
lda PLAYER_DIR
bne +
;if we moved in x, reached full char pos again?
lda SPRITE_DIRECTION,x
beq +
lda SPRITE_CHAR_POS_X_DELTA,x
bne +
;yes!
lda #0
sta SPRITE_DIRECTION,x
+
rts
!zone IsEnemyCollidingWithObject
.CalculateSimpleXPos
;Returns a with simple x pos (x halved + 128 if > 256)
;modifies y
lda BIT_TABLE,x
and SPRITE_POS_X_EXTEND
beq .NoXBit
lda SPRITE_POS_X,x
lsr
clc
adc #128
rts
.NoXBit
lda SPRITE_POS_X,x
lsr
rts
;modifies X
;check y pos
;check object collision with other object (object CURRENT_INDEX vs CURRENT_SUB_INDEX)
;return a = 1 when colliding, a = 0 when not
;------------------------------------------------------------
;temp PARAM8 holds height to check in pixels
IsEnemyCollidingWithObject
ldx CURRENT_SUB_INDEX
ldy CURRENT_INDEX
lda SPRITE_HEIGHT_CHARS,y
asl
asl
asl
sta PARAM8
lda SPRITE_POS_Y,y
sta PARAM2
lda SPRITE_POS_Y,x
sec
sbc PARAM8 ;offset to bottom
cmp PARAM2
bcs .NotTouching
;sprite x is above sprite y
clc
adc PARAM8
sta PARAM1
lda SPRITE_HEIGHT_CHARS,x
asl
asl
asl
clc
adc PARAM1
cmp PARAM2
bcc .NotTouching
;X = Index in enemy-table
jsr .CalculateSimpleXPos
sta PARAM1
ldx CURRENT_INDEX
jsr .CalculateSimpleXPos
sec
sbc #8 ;was 4
;position X-Anfang Player - 12 Pixel
cmp PARAM1
bcs .NotTouching
adc #16 ;was 8
cmp PARAM1
bcc .NotTouching
lda #1
;sta VIC.BORDER_COLOR
rts
.NotTouching
lda #0
;sta VIC.BORDER_COLOR
rts
;------------------------------------------------------------
;fly left/right
;------------------------------------------------------------
!if 0 {
!zone BehaviourBird
BehaviourBird
lda ENEMY_SPELL
cmp #2
beq .NoAnimUpdate
jsr HandleBehaviour
lda BEHAVIOUR_QUICKER
beq .SingleAnimStep
jsr .AnimStep
.SingleAnimStep
jmp .AnimStep
.AnimStep
inc SPRITE_ANIM_DELAY,x
lda SPRITE_ANIM_DELAY,x
cmp #4
bne .NoAnimUpdate
lda #0
sta SPRITE_ANIM_DELAY,x
inc SPRITE_ANIM_POS,x
lda SPRITE_ANIM_POS,x
and #$03
sta SPRITE_ANIM_POS,x
tay
lda SPRITE_DIRECTION,x
beq .FacingLeft
lda #3
.FacingLeft
clc
adc #SPRITE_BIRD_FLY_R_1
adc PING_PONG_ANIM_TABLE,y
sta SPRITE_POINTER_BASE,x
.NoAnimUpdate
rts
}
!zone FindEmptySpriteSlot
;Looks for an empty sprite slot, returns in X. Starts with Index X
;#1 in A when empty slot found, #0 when full
FindEmptySpriteSlot
.CheckSlot
lda SPRITE_ACTIVE,x
beq .FoundSlot
inx
cpx #8
bne .CheckSlot
lda #0
rts
.FoundSlot
lda #1
rts
!zone RemoveObject
;Removed object from array
;X = index of object
RemoveObject
;remove from array
lda #0
sta SPRITE_ACTIVE,x
;disable sprite
lda BIT_TABLE,x
eor #$ff
and VIC.SPRITE_ENABLE
sta VIC.SPRITE_ENABLE
lda BIT_TABLE,x
eor #$ff
and VIC.SPRITE_EXPAND_X
sta VIC.SPRITE_EXPAND_X
lda BIT_TABLE,x
eor #$ff
and VIC.SPRITE_EXPAND_Y
sta VIC.SPRITE_EXPAND_Y
rts
;------------------------------------------------------------
;move object left if not blocked
;x = object index
;returns: a=1 if moved, a=0 if blocked
;------------------------------------------------------------
!zone ObjectMoveLeftBlocking
ObjectMoveLeftBlocking
lda SPRITE_CHAR_POS_X_DELTA,x
beq .CheckCanMoveLeft
.CanMoveLeft
jsr ObjectMoveLeft
lda #1
rts
.CheckCanMoveLeft
lda #DIR_W
sta MOVE_DIR
lda SPRITE_CHAR_POS_X,x
beq .BlockedLeft
;lbeq HitTile.HitWallSound
lda SPRITE_CHAR_POS_Y,x
sec
sbc SPRITE_HEIGHT_CHARS,x
bmi .BlockedLeft
tay
iny
sty PARAM2
lda SCREEN_LINE_OFFSET_TABLE_LO,y
sta ZEROPAGE_POINTER_1
lda SCREEN_LINE_OFFSET_TABLE_HI,y
sta ZEROPAGE_POINTER_1 + 1
lda SPRITE_HEIGHT_CHARS,x
sta PARAM6
lda SPRITE_CHAR_POS_Y_DELTA,x
beq +
inc PARAM6
+
--
lda SPRITE_CHAR_POS_X,x
dec
asl
tay
lda (ZEROPAGE_POINTER_1),y
jsr IsCharBlocking
bne .BlockedLeft
inc PARAM2
dec PARAM6
beq .CanMoveLeft
lda ZEROPAGE_POINTER_1
clc
adc #80
sta ZEROPAGE_POINTER_1
bcc +
inc ZEROPAGE_POINTER_1 + 1
+
jmp --
.BlockedLeft
tya
lsr
lsr
sta PARAM1
lsr PARAM2
;PARAM1,PARAM2 = screen tile pos
lda #DIR_W
sta HIT_DIR
jsr HitTile
lda #1
sta BLOCKED_DIR
lda #0
rts
;------------------------------------------------------------
;move object left
;x = object index
;------------------------------------------------------------
!zone ObjectMoveLeft
ObjectMoveLeft
lda SPRITE_NUM_PARTS,x
sta PARAM11
-
lda SPRITE_CHAR_POS_X_DELTA,x
bne .NoCharStep
lda #8
sta SPRITE_CHAR_POS_X_DELTA,x
dec SPRITE_CHAR_POS_X,x
.NoCharStep
dec SPRITE_CHAR_POS_X_DELTA,x
jsr MoveSpriteLeft
inx
dec PARAM11
bne -
lda SPRITE_MAIN_INDEX - 1,x
tax
rts
;------------------------------------------------------------
;move object right if not blocked
;x = object index
;return a=1 when moved, 0 when blocked
;------------------------------------------------------------
!zone ObjectMoveRightBlocking
ObjectMoveRightBlocking
lda SPRITE_CHAR_POS_X_DELTA,x
beq .CheckCanMoveRight
.CanMoveRight
jsr ObjectMoveRight
lda #1
rts
.CheckCanMoveRight
lda #DIR_E
sta MOVE_DIR
ldy #40
lda SPRITE_CHAR_POS_X,x
cmp #39
lbeq HitTile.HitWallSound
lda SPRITE_CHAR_POS_Y,x
sec
sbc SPRITE_HEIGHT_CHARS,x
bmi .BlockedRight
tay
iny
sty PARAM2
lda SCREEN_LINE_OFFSET_TABLE_LO,y
sta ZEROPAGE_POINTER_1
lda SCREEN_LINE_OFFSET_TABLE_HI,y
sta ZEROPAGE_POINTER_1 + 1
lda SPRITE_HEIGHT_CHARS,x
sta PARAM6
lda SPRITE_CHAR_POS_Y_DELTA,x
beq +
inc PARAM6
+
--
lda SPRITE_CHAR_POS_X,x
clc
adc SPRITE_WIDTH_CHARS,x
asl
tay
lda (ZEROPAGE_POINTER_1),y
jsr IsCharBlocking
bne .BlockedRight
inc PARAM2
dec PARAM6
beq .CanMoveRight
lda ZEROPAGE_POINTER_1
clc
adc #80
sta ZEROPAGE_POINTER_1
bcc +
inc ZEROPAGE_POINTER_1 + 1
+
jmp --
.BlockedRight
tya
lsr
lsr
sta PARAM1
lsr PARAM2
;PARAM1,PARAM2 = screen char pos
lda #DIR_E
sta HIT_DIR
jsr HitTile
lda #1
sta BLOCKED_DIR
lda #0
rts
;------------------------------------------------------------
;move object right
;x = object index
;------------------------------------------------------------
!zone ObjectMoveRight
ObjectMoveRight
lda SPRITE_NUM_PARTS,x
sta PARAM11
-
inc SPRITE_CHAR_POS_X_DELTA,x
lda SPRITE_CHAR_POS_X_DELTA,x
cmp #8
bne .NoCharStep
lda #0
sta SPRITE_CHAR_POS_X_DELTA,x
inc SPRITE_CHAR_POS_X,x
.NoCharStep
jsr MoveSpriteRight
inx
dec PARAM11
bne -
lda SPRITE_MAIN_INDEX - 1,x
tax
rts
;------------------------------------------------------------
;move object up if not blocked
;x = object index
;return a=1 when moved, 0 when blocked
;------------------------------------------------------------
!zone ObjectMoveUpBlocking
ObjectMoveUpBlocking
lda SPRITE_CHAR_POS_Y_DELTA,x
beq .CheckCanMoveUp
.CanMoveUp
jsr ObjectMoveUp
lda #1
rts
.CheckCanMoveUp
lda #DIR_N
sta MOVE_DIR
;at top of screen?
lda SPRITE_CHAR_POS_Y,x
sec
sbc SPRITE_HEIGHT_CHARS,x
bmi .BlockedTop
beq .BlockedTop
.CheckUp
lda SPRITE_WIDTH_CHARS,x
sta PARAM5
lda SPRITE_CHAR_POS_X_DELTA,x
beq .NoSecondCharCheckNeeded
inc PARAM5
.NoSecondCharCheckNeeded
lda SPRITE_CHAR_POS_Y,x
sec
sbc SPRITE_HEIGHT_CHARS,x
tay
sty PARAM2
lda SCREEN_LINE_OFFSET_TABLE_LO,y
sta ZEROPAGE_POINTER_1
lda SCREEN_LINE_OFFSET_TABLE_HI,y
sta ZEROPAGE_POINTER_1 + 1
lda SPRITE_CHAR_POS_X,x
asl
dec
dec
tay
-
iny
iny
lda (ZEROPAGE_POINTER_1),y
jsr IsCharBlocking
bne .BlockedUp
dec PARAM5
bne -
jmp .CanMoveUp
.BlockedTop
cpx ACTIVE_PLAYER_INDEX
bne .BlockedUp
lda SPRITE_CHAR_POS_Y,x
sec
sbc SPRITE_HEIGHT_CHARS,x
bmi .CanMoveUp
beq .CanMoveUp
jmp .CheckUp
.BlockedUp
tya
lsr
lsr
sta PARAM1
lsr PARAM2
;PARAM1,PARAM2 = screen char pos
lda #DIR_N
sta HIT_DIR
jsr HitTile
lda #2
sta BLOCKED_DIR
lda #0
rts
;------------------------------------------------------------
;move object up
;x = object index
;------------------------------------------------------------
!zone ObjectMoveUp
ObjectMoveUp
lda SPRITE_NUM_PARTS,x
sta PARAM11
-
dec SPRITE_CHAR_POS_Y_DELTA,x
lda SPRITE_CHAR_POS_Y_DELTA,x
cmp #$ff
bne .NoCharStep
dec SPRITE_CHAR_POS_Y,x
lda #7
sta SPRITE_CHAR_POS_Y_DELTA,x
.NoCharStep
jsr MoveSpriteUp
inx
dec PARAM11
bne -
lda SPRITE_MAIN_INDEX - 1,x
tax
rts
;move object down if not blocked
;x = object index
;a = 1 if moved, 0 if blocked
!zone ObjectMoveDownBlocking
ObjectMoveDownBlocking
lda SPRITE_CHAR_POS_Y_DELTA,x
bne +
lda #DIR_S
sta MOVE_DIR
jsr CheckCanMoveDown
bne +
ldy #2
sty BLOCKED_DIR
lda #0
rts
+
jsr ObjectMoveDown
lda #1
rts
;------------------------------------------------------------
;move object down
;x = object index
;------------------------------------------------------------
!zone ObjectMoveDown
ObjectMoveDown
lda SPRITE_NUM_PARTS,x
sta PARAM11
-
inc SPRITE_CHAR_POS_Y_DELTA,x
lda SPRITE_CHAR_POS_Y_DELTA,x
cmp #8
bne .NoCharStep
lda #0
sta SPRITE_CHAR_POS_Y_DELTA,x
inc SPRITE_CHAR_POS_Y,x
.NoCharStep
jsr MoveSpriteDown
inx
dec PARAM11
bne -
lda SPRITE_MAIN_INDEX - 1,x
tax
rts
!zone CheckCanMoveDown
;returns 0 if blocked, 1 if move is possible
CheckCanMoveDown
lda SPRITE_WIDTH_CHARS,x
sta PARAM5
lda SPRITE_CHAR_POS_X_DELTA,x
beq .NoSecondCharCheckNeeded
inc PARAM5
.NoSecondCharCheckNeeded
ldy SPRITE_CHAR_POS_Y,x
iny
sty PARAM2
cpy #24
lbcs HitTile.HitWallSound
lda SCREEN_LINE_OFFSET_TABLE_LO,y
sta ZEROPAGE_POINTER_1
lda SCREEN_LINE_OFFSET_TABLE_HI,y
sta ZEROPAGE_POINTER_1 + 1
lda SPRITE_CHAR_POS_X,x
asl
dec
dec
tay
-
iny
iny
lda (ZEROPAGE_POINTER_1),y
jsr IsCharBlocking
bne .BlockedDown
dec PARAM5
bne -
;not blocked
lda #1
rts
.BlockedDown
tya
lsr
lsr
sta PARAM1
lsr PARAM2
;PARAM1,PARAM2 = screen char pos
lda #DIR_S
sta HIT_DIR
jsr HitTile
lda #0
rts
.BlockedDownBorder
.HitWallSound
lda #0
sta PLAYER_AFFECTED
rts
;------------------------------------------------------------
;Enemy Behaviour
;------------------------------------------------------------
!zone ObjectControl
ObjectControl
stx CURRENT_INDEX
.ObjectLoop
ldy SPRITE_ACTIVE,x
beq .NextObject
lda SPRITE_HITBACK,x
beq +
dec SPRITE_HITBACK,x
bne +
lda SPRITE_HITBACK_ORIG_COLOR,x
sta VIC.SPRITE_COLOR,x
+
;enemy is active
dey
lda ENEMY_BEHAVIOUR_TABLE_LO,y
sta .JumpPointer + 1
lda ENEMY_BEHAVIOUR_TABLE_HI,y
sta .JumpPointer + 2
.JumpPointer
jsr $8000
cpx CURRENT_INDEX
beq +
inc VIC.BORDER_COLOR
+
.NextObject
inc CURRENT_INDEX
ldx CURRENT_INDEX
cpx #8
bne .ObjectLoop
rts
;------------------------------------------------------------
;Move Sprite Left
;expect x as sprite index (0 to 7)
;------------------------------------------------------------
!zone MoveSpriteLeft
MoveSpriteLeft
dec SPRITE_POS_X,x
bpl .NoChangeInExtendedFlag
lda BIT_TABLE,x
trb SPRITE_POS_X_EXTEND
trb VIC.SPRITE_X_EXTEND
.NoChangeInExtendedFlag
txa
asl
tay
lda SPRITE_POS_X,x
sta VIC.SPRITE_X_POS,y
rts
;------------------------------------------------------------
;Move Sprite Right
;expect x as sprite index (0 to 7)
;------------------------------------------------------------
!zone MoveSpriteRight
MoveSpriteRight
inc SPRITE_POS_X,x
lda SPRITE_POS_X,x
bne .NoChangeInExtendedFlag
lda BIT_TABLE,x
tsb SPRITE_POS_X_EXTEND
tsb VIC.SPRITE_X_EXTEND
.NoChangeInExtendedFlag
txa
asl
tay
lda SPRITE_POS_X,x
sta VIC.SPRITE_X_POS,y
rts
;------------------------------------------------------------
;Move Sprite Up
;expect x as sprite index (0 to 7)
;------------------------------------------------------------
!zone MoveSpriteUp
MoveSpriteUp
dec SPRITE_POS_Y,x
txa
asl
tay
lda SPRITE_POS_Y,x
sta VIC.SPRITE_Y_POS,y
rts
;------------------------------------------------------------
;Move Sprite Down
;expect x as sprite index (0 to 7)
;------------------------------------------------------------
!zone MoveSpriteDown
MoveSpriteDown
inc SPRITE_POS_Y,x
txa
asl
tay
lda SPRITE_POS_Y,x
sta VIC.SPRITE_Y_POS,y
rts
;------------------------------------------------------------
;IsCharBlocking
;checks if a char is blocking
;A = character, ZEROPAGE_POINTER1 + y is char offset
;returns 1 for blocking, 0 for not blocking,
; sets HIT_CRUMBLE if char was crumble and returns 1
;------------------------------------------------------------
!zone IsCharBlocking