dos33fsprogs/games/keen/level1_enemies.s

NUM_ENEMIES = 4


	;=======================
	; move enemies
	;=======================

move_enemies:

	ldy	#0

move_enemies_loop:

	; only move if out

	lda	enemy_data+ENEMY_DATA_OUT,Y
	beq	done_move_enemy

	; check if falling


	; check if moving right/left

;	lda	enemy_data+ENEMY_DATA_X,Y
;	clc
;	adc	#1
;	sta	enemy_data+ENEMY_DATA_X,Y

;	cmp	#36
;	bcc	done_move_enemy

;	lda	#0
;	sta	enemy_data+ENEMY_DATA_OUT,Y

done_move_enemy:

	iny
	cpy	#NUM_ENEMIES
	bne	move_enemies_loop

	rts



	;=======================
	; draw and move enemies
	;=======================
draw_enemies:

	ldy	#0
draw_enemies_loop:

	; see if out

	lda	enemy_data+ENEMY_DATA_OUT,Y
	beq	done_draw_enemy

	; check if on screen

;	lda	TILEMAP_X
;	cmp	enemy_data+ENEMY_DATA_TILEX,Y
;	bcs	done_draw_enemy

;	clc
;	adc	#14
;	cmp	enemy_data+ENEMY_DATA_TILEX,Y
;	bcc	done_draw_enemy

;	lda	TILEMAP_Y
;	cmp	enemy_data+ENEMY_DATA_TILEY,Y
;	bcs	done_draw_enemy

;	clc
;	adc	#10
;	cmp	enemy_data+ENEMY_DATA_TILEY,Y
;	bcc	done_draw_enemy

	; set X and Y value
	; convert tile values to X,Y
	; X = (ENEMY_TILE_X-TILEX)*2 + 6
;	lda	enemy_data+ENEMY_DATA_TILEX,Y
;	sec
;	sbc	TILEMAP_X
;	asl
;	clc
;	adc	#4
;	sta	XPOS

	; Y = (ENEMY_TILE_Y-TILEY)*4
;	lda	enemy_data+ENEMY_DATA_TILEY,Y
;	sec
;	sbc	TILEMAP_Y
;	asl
;	asl
;	sta	YPOS

	; see if exploding
;	lda	enemy_data+ENEMY_DATA_EXPLODING,Y
;	beq	draw_proper_enemy
;draw_exploding_enemy:
;	asl
;	tax
;	lda	enemy_explosion_sprites,X
;	sta	INL
;	lda	enemy_explosion_sprites+1,X
;	sta	INH

;	lda	FRAMEL
;	and	#$3
;	bne	done_exploding

	; move to next frame
;	lda	enemy_data+ENEMY_DATA_EXPLODING,Y
;	clc
;	adc	#1
;	sta	enemy_data+ENEMY_DATA_EXPLODING,Y

;	cmp	#4
;	bne	done_exploding
;	lda	#0
;	sta	enemy_data+ENEMY_DATA_OUT,Y

;done_exploding:
;	jmp	draw_enemy

	; otherwise draw proper sprite
draw_proper_enemy:
;	lda	enemy_data+ENEMY_DATA_TYPE,Y
;	tax
;	lda	enemy_sprites,X
;	sta	INL
;	lda	enemy_sprites+1,X
;	sta	INH

	lda	#<yorp_sprite_walking_right
	sta	INL

	lda	#>yorp_sprite_walking_right
	sta	INH

	lda	enemy_data+ENEMY_DATA_X,Y
	sta	XPOS
	lda	enemy_data+ENEMY_DATA_Y,Y
	sta	YPOS



draw_enemy:
	tya
	pha

	jsr	put_sprite_crop

	pla
	tay

done_draw_enemy:

	tya
	clc
	adc	#8
	tay
	cpy	#(NUM_ENEMIES*8)
	beq	exit_draw_enemy
	jmp	draw_enemies_loop

exit_draw_enemy:
	rts

enemy_explosion_sprites:
	.word	enemy_explosion_sprite1
	.word	enemy_explosion_sprite1
	.word	enemy_explosion_sprite2
	.word	enemy_explosion_sprite3

enemy_explosion_sprite1:
	.byte	2,2
	.byte	$d9,$d9
	.byte	$9d,$9d

enemy_explosion_sprite2:
	.byte	2,2
	.byte	$9A,$9A
	.byte	$A9,$A9

enemy_explosion_sprite3:
	.byte	2,2
	.byte	$7A,$5A
	.byte	$A5,$A7

ENEMY_YORP	= 0

ENEMY_DATA_OUT		= 0
ENEMY_DATA_EXPLODING	= 1
ENEMY_DATA_TYPE		= 2
ENEMY_DATA_DIRECTION	= 3
ENEMY_DATA_TILEX	= 4
ENEMY_DATA_TILEY	= 5
ENEMY_DATA_X		= 6
ENEMY_DATA_Y		= 7


enemy_data:

enemy0:
	; 156,92 (-80,-12) -> 76,80 -> (/4,/4) -> 19,20
	.byte	1		; out
	.byte	0		; exploding
	.byte	ENEMY_YORP	; type
	.byte	$ff		; direction
	.byte	19,20		; tilex,tiley
	.byte	10,10		; x,y

enemy1:
	; 272,92 (-80,-12) -> 192,80 -> (/4,/4) -> 48,20
	.byte	0		; out
	.byte	0		; exploding
	.byte	ENEMY_YORP	; type
	.byte	$ff		; direction
	.byte	48,20		; tilex,tiley
	.byte	0,0		; x,y

enemy2:
	; 156,112 (-80,-12) -> 76,100 -> (/4,/4) -> 19,25
	.byte	0		; out
	.byte	0		; exploding
	.byte	ENEMY_YORP	; type
	.byte	$ff		; direction
	.byte	19,25		; tilex,tiley
	.byte	0,0		; x,y

enemy3:
	; 184,116 (-80,-12) -> 104,104 -> (/4,/4) -> 26,26
	.byte	0		; out
	.byte	0		; exploding
	.byte	ENEMY_YORP	; type
	.byte	$ff		; direction
	.byte	26,26		; tilex,tiley
	.byte	0,0		; x,y