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;; Shared code for palettes across scrolling examples.
.scope Palettes
DEFAULT_COLOR = $11
;; Copies all the palettes for our game into the proper PPU address.
;;
;; NOTE: as explained in `metatile.s`, the engine for the scrolling examples
;; lack the ability to update the attributes for each tile. This is
;; embarrasing, but adding support for it would make these examples more
;; complex than they need to be. Hence we just reproduce the same palette
;; all over and avoid glitches on real hardware or emulators with randomized
;; memory.
.proc init
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
.byte DEFAULT_COLOR, $36, $17, $0F
.byte DEFAULT_COLOR, $36, $17, $0F
.byte DEFAULT_COLOR, $36, $17, $0F
.byte DEFAULT_COLOR, $36, $17, $0F
;; Foreground
.byte DEFAULT_COLOR, $28, $0F, $30
.byte DEFAULT_COLOR, $28, $0F, $30
.byte DEFAULT_COLOR, $28, $0F, $30
.byte DEFAULT_COLOR, $28, $0F, $30
.endproc
.endscope
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