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|
.org 0
.equ INT_VECTOR 0xff00
call init
game_loop:
halt
call entities_erase
call stars_update
call entities_update
call entities_draw
jmp game_loop
init:
; setup an int handler so we
; can use the frame int to sync
ld a, >INT_VECTOR
ld x, <INT_VECTOR
ld b, <int_handler
ld [a : x], b
inc x
ld b, >int_handler
ld [a : x], b
; enable interrupts
cif
halt
; erase the screen
ld b, 0
ld a, 0xbf
ld x, 0
ld y, 0x40
fill_loop:
ld [a : x], b
inc x
bno
jmp fill_loop
inc a
dec y
bnz
jmp fill_loop
call entities_draw
ret
int_handler:
iret
.include "starfield.asm"
.include "entities.asm"
.include "player.asm"
;
; entity data
;
entities:
; type
.db ET_PLAYER
; x, y
.db 0, 0
; frame
.db 0
.dw player_sprite
.dw player_update
; end of list
.db ET_END
; sprite data
player_sprite:
.incpng "assets/player.png"
; starfield data
stars:
; video addr, speed, color
.dw 0xc361
.db 1, 15
.dw 0xc204
.db 1, 6
.dw 0xcdf9
.db 1, 15
.dw 0xdb87
.db 1, 3
.dw 0xd242
.db 1, 15
.dw 0xdeea
.db 1, 6
.dw 0xe7af
.db 1, 15
.dw 0xed68
.db 1, 3
.dw 0xf812
.db 1, 15
.dw 0xfbca
.db 1, 13
.dw 0xc361
.db 2, 8
.dw 0xc204
.db 2, 9
.dw 0xcdf9
.db 3, 7
.dw 0xdb87
.db 3, 4
.dw 0xd242
.db 2, 8
.dw 0xdeea
.db 3, 9
.dw 0xe7af
.db 3, 6
.dw 0xed68
.db 2, 9
.dw 0xf812
.db 3, 14
.dw 0xfbca
.db 2, 3
; end of list
.dw 0xffff
|
