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.segment "HEADER"
.byte 'N', 'E', 'S', $1A
.byte $02, $01
.res $0A, $00
.segment "CODE"
.include "../include/apu.s"
.include "../include/oam.s"
.include "../include/ppu.s"
.include "../include/globals.s"
.include "vectors.s"
.proc main
jsr init_palettes
jsr init_nametables
;;; TODO
cli
lda #%10110000
sta $2000
lda #%00011110
sta $2001
@main_game_loop:
;;;
;; TODO
;;;
lda #%10000000
ora Globals::zp_flags
sta Globals::zp_flags
@wait_for_render:
bit Globals::zp_flags
bmi @wait_for_render
;; Rendering is done, we can perform another iteration of the loop!
jmp @main_game_loop
.endproc
;; Copies all the palettes for our game into the proper PPU address.
.proc init_palettes
lda #$3F
sta PPU::ADDRESS
lda #$00
sta PPU::ADDRESS
ldx #0
@load_palettes_loop:
lda palettes, x
sta PPU::DATA
inx
cpx #$20
bne @load_palettes_loop
rts
palettes:
;; Background
;; 0: score
.byte $0F, $30, $2C, $28
;; 1: floating platforms
.byte $0F, $2C, $30, $2A
;; 2: ground
.byte $0F, $28, $14, $28
;; 3: ship
.byte $0F, $16, $30, $00
;; TODO: fuel tank needs color $24
;; Foreground
;; 0: player & ship
.byte $0F, $16, $10, $30
;; 1: enemy 1 & bonuses
.byte $0F, $16, $2C, $2A
;; 2: enemy 2, fuel & bonuses
.byte $0F, $16, $14, $28
;; 3: SUSE easter egg
.byte $0F, $16, $00, $2B
.endproc
.proc init_nametables
;; TODO
rts
.endproc
.segment "CHARS"
.incbin "../assets/jetpac.chr"
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