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| author | Miquel Sabaté Solà <mssola@mssola.com> | 2026-03-07 23:27:28 +0100 |
|---|---|---|
| committer | Miquel Sabaté Solà <mssola@mssola.com> | 2026-03-08 16:50:06 +0100 |
| commit | 220c80b987ba54d709180e3d95e9e0d82af4249c (patch) | |
| tree | 2b84b016d70650ad57a2acb8ad6ca7c28ff8629d | |
| parent | e8f39dc4a7cc19fb97e24ec0819ccd964cbd325f (diff) | |
| download | jetpac.nes-220c80b987ba54d709180e3d95e9e0d82af4249c.tar.gz jetpac.nes-220c80b987ba54d709180e3d95e9e0d82af4249c.zip | |
Define the bitmap for multiplayer support
Also give it a dummy value on start and initialize it properly after the
player's selection on the title screen.
Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>
| -rw-r--r-- | .nasm/memory.txt | 3 | ||||
| -rw-r--r-- | .nasm/segments.txt | 2 | ||||
| -rw-r--r-- | include/globals.s | 9 | ||||
| -rw-r--r-- | src/jetpac.s | 1 | ||||
| -rw-r--r-- | src/title.s | 11 |
5 files changed, 23 insertions, 3 deletions
diff --git a/.nasm/memory.txt b/.nasm/memory.txt index 66efcb4..dcdef5e 100644 --- a/.nasm/memory.txt +++ b/.nasm/memory.txt @@ -21,6 +21,7 @@ $22: zp_buttons1 $23: zp_buttons2 $24: zp_level $25: zp_level_kind +$26: zp_multiplayer $30: zp_title_timer $32: zp_pause_timer $33: zp_next_bullet_cycle @@ -69,4 +70,4 @@ $4016: m_joypad1 $4017: m_frame_counter --- Summary (in bytes) --- -- Internal RAM: 390/2048 (19.04%) +- Internal RAM: 391/2048 (19.09%) diff --git a/.nasm/segments.txt b/.nasm/segments.txt index 191f81e..ae19530 100644 --- a/.nasm/segments.txt +++ b/.nasm/segments.txt @@ -1,4 +1,4 @@ - HEADER: 16/16 (100%) -- ROM0: 6544/32762 (19.97%) +- ROM0: 6559/32762 (20.02%) - ROMV: 6/6 (100%) - ROM2: 8192/8192 (100%) diff --git a/include/globals.s b/include/globals.s index ca85d33..f6021b4 100644 --- a/include/globals.s +++ b/include/globals.s @@ -45,4 +45,13 @@ ;; "kind" repeats every 8 waves. Hence, this is just a cached version of ;; masking `zp_level`. zp_level_kind = $25 + + ;; | Bit | Short name | Meaning | + ;; |-----+------------------+--------------------------| + ;; | 7 | enabled | Multiplayer enabled. | + ;; | 6-3 | - | Unused. | + ;; | 2 | player's 2 state | 0: over; 1: alive | + ;; | 1 | player's 1 state | 0: over; 1: alive | + ;; | 0 | active | 0: player 1; 1: player 2 | + zp_multiplayer = $26 .endscope diff --git a/src/jetpac.s b/src/jetpac.s index 52ec1f7..e8d6543 100644 --- a/src/jetpac.s +++ b/src/jetpac.s @@ -124,6 +124,7 @@ ;; have zero as their initial values. Note that it's important to have these ;; variables defined before sta Globals::zp_flags + sta Globals::zp_multiplayer sta Joypad::zp_buttons1 sta Joypad::zp_buttons2 sta Player::zp_state diff --git a/src/title.s b/src/title.s index e3a2086..06ca1cb 100644 --- a/src/title.s +++ b/src/title.s @@ -89,9 +89,18 @@ rts .endproc - ;; Save the selection from the menu (TODO), hide all elements from the title + ;; Save the selection from the menu, hide all elements from the title ;; screen, and return always 1. .proc start + ;; Select whether player 2 is to be alive or not. + lda #%00000010 + ldx OAM::m_sprites + cpx #SPRITE_Y_POSITION1 + bne @set_multi + ora #%10000100 + @set_multi: + sta Globals::zp_multiplayer + ;; Hide the sprite from the menu. lda #$EF sta OAM::m_sprites |