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| author | Miquel Sabaté Solà <msabate@suse.com> | 2024-04-02 22:02:59 +0200 |
|---|---|---|
| committer | Miquel Sabaté Solà <mikisabate@gmail.com> | 2025-02-04 21:04:01 +0100 |
| commit | 1d1f08646352df00977a88adb99e04d54e4dfd5d (patch) | |
| tree | 4efb0259708c0b67ec4ed3876cb487e72073b584 /shared/diskun.s | |
| parent | c6bc9014c10858b8cfd482289c9691b11ef6ad39 (diff) | |
| download | code.nes-1d1f08646352df00977a88adb99e04d54e4dfd5d.tar.gz code.nes-1d1f08646352df00977a88adb99e04d54e4dfd5d.zip | |
basics: Add a flickering example
Add an example on how to flicker sprites so to not surpass the scanline
limit for them.
Signed-off-by: Miquel Sabaté Solà <msabate@suse.com>
Diffstat (limited to 'shared/diskun.s')
| -rw-r--r-- | shared/diskun.s | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/shared/diskun.s b/shared/diskun.s new file mode 100644 index 0000000..d8bab90 --- /dev/null +++ b/shared/diskun.s @@ -0,0 +1,95 @@ +;;; Simple sprite that can be moved with the dpad easily. Use it to have +;;; something funny moving. + +.include "joypad.s" + +.scope Diskun + m_screen_x = $30 + m_screen_y = $31 + + .proc init_palettes + lda #$3F + sta $2006 ; PPUADDR + lda #$00 + sta $2006 ; PPUADDR + + ldx #0 + @load_palettes_loop: + lda palettes, x + sta $2007 ; PPUDATA + inx + cpx #$20 + bne @load_palettes_loop + rts + palettes: + DEFAULT_COLOR = $11 + + ;; Background + .byte DEFAULT_COLOR, $36, $17, $0F + .byte DEFAULT_COLOR, $00, $00, $00 + .byte DEFAULT_COLOR, $00, $00, $00 + .byte DEFAULT_COLOR, $00, $00, $00 + + ;; Foreground + .byte DEFAULT_COLOR, $28, $0F, $30 + .byte DEFAULT_COLOR, $00, $00, $00 + .byte DEFAULT_COLOR, $00, $00, $00 + .byte DEFAULT_COLOR, $00, $00, $00 + + rts + .endproc + + .proc update + lda #Joypad::BUTTON_UP + and Joypad::m_buttons1 + beq @check_down + + dec Diskun::m_screen_y + dec Diskun::m_screen_y + jmp @check_left + @check_down: + lda #Joypad::BUTTON_DOWN + and Joypad::m_buttons1 + beq @check_left + + inc Diskun::m_screen_y + inc Diskun::m_screen_y + @check_left: + lda #Joypad::BUTTON_LEFT + and Joypad::m_buttons1 + beq @check_right + + dec Diskun::m_screen_x + dec Diskun::m_screen_x + @check_right: + lda #Joypad::BUTTON_RIGHT + and Joypad::m_buttons1 + beq @end + + inc Diskun::m_screen_x + inc Diskun::m_screen_x + @end: + rts + .endproc + + .proc nmi_update + lda Diskun::m_screen_x + sta $203 + sta $20B + clc + adc #8 + sta $207 + sta $20F + + lda Diskun::m_screen_y + sta $200 + sta $204 + clc + adc #8 + sta $208 + sta $20C + + rts + .endproc +.endscope + |