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| author | Miquel Sabaté Solà <mssola@mssola.com> | 2026-04-02 14:40:12 +0200 |
|---|---|---|
| committer | Miquel Sabaté Solà <mssola@mssola.com> | 2026-04-02 14:40:12 +0200 |
| commit | cb1111055f7b03989daac63675d27bfd156a4e21 (patch) | |
| tree | a3038f24c830b053dc7b63e7935f63e0bd50f7b3 | |
| parent | ba2711cb490c26e05c1b8f6cd3e1d081309d15fd (diff) | |
| download | jetpac.nes-cb1111055f7b03989daac63675d27bfd156a4e21.tar.gz jetpac.nes-cb1111055f7b03989daac63675d27bfd156a4e21.zip | |
Cycle the kind of shuttle to be used
In preparation to having multiple kinds of shuttles as in the original
game, introduce the 'Globals::zp_shuttle_kind' variable, which is just a
helper value by masking out the 'Globals::zp_level' variable. This in
turn will be the index for selecting which tile IDs for each shuttle
part.
Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>
| -rw-r--r-- | .nasm/memory.txt | 7 | ||||
| -rw-r--r-- | .nasm/segments.txt | 2 | ||||
| -rw-r--r-- | include/globals.s | 8 | ||||
| -rw-r--r-- | src/driver.s | 5 | ||||
| -rw-r--r-- | src/jetpac.s | 6 |
5 files changed, 22 insertions, 6 deletions
diff --git a/.nasm/memory.txt b/.nasm/memory.txt index b7a16bc..35133c5 100644 --- a/.nasm/memory.txt +++ b/.nasm/memory.txt @@ -22,8 +22,9 @@ $21: zp_prev $22: zp_buttons $24: zp_level $25: zp_level_kind -$26: zp_multiplayer -$27: zp_extra_flags +$26: zp_shuttle_kind +$27: zp_multiplayer +$28: zp_extra_flags $2E: zp_blink_status $2F: zp_blink_timer $30: zp_title_timer @@ -84,4 +85,4 @@ $4016: m_joypad $4017: m_frame_counter --- Summary (in bytes) --- -- Internal RAM: 438/2048 (21.39%) +- Internal RAM: 439/2048 (21.44%) diff --git a/.nasm/segments.txt b/.nasm/segments.txt index a741401..229318f 100644 --- a/.nasm/segments.txt +++ b/.nasm/segments.txt @@ -1,4 +1,4 @@ - HEADER: 16/16 (100%) -- ROM0: 9120/32762 (27.84%) +- ROM0: 9136/32762 (27.89%) - ROMV: 6/6 (100%) - ROM2: 8192/8192 (100%) diff --git a/include/globals.s b/include/globals.s index a958778..515d5d4 100644 --- a/include/globals.s +++ b/include/globals.s @@ -48,6 +48,10 @@ ;; masking `zp_level`. zp_level_kind = $25 + ;; The kind of shuttle to be used. As with 'zp_level_kind', this is just a + ;; cached version of masking 'zp_level'. + zp_shuttle_kind = $26 + ;; | Bit | Short name | Meaning | ;; |-----+------------------+--------------------------| ;; | 7 | enabled | Multiplayer enabled. | @@ -55,7 +59,7 @@ ;; | 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 + zp_multiplayer = $27 ;; Extra bitmap that was needed beyond the ones that we already have. Yeah, ;; I know, bad planning from my side, but now it's a bit complex to untangle @@ -66,5 +70,5 @@ ;; | 7 | score | The score has been updated. | ;; | 6 | high | The high score has been updated. | ;; | 5-0 | - | Unused. | - zp_extra_flags = $27 + zp_extra_flags = $28 .endscope diff --git a/src/driver.s b/src/driver.s index b367c63..9d31604 100644 --- a/src/driver.s +++ b/src/driver.s @@ -885,6 +885,11 @@ lda Globals::zp_level and #%00000111 sta Globals::zp_level_kind + lda Globals::zp_level + and #%00001100 + lsr + lsr + sta Globals::zp_shuttle_kind ;; Just like we did in Drivers::switch(), we re-initialize some things ;; like timers and the items. Note that re-setting the timers will force diff --git a/src/jetpac.s b/src/jetpac.s index 5716be8..b9e6311 100644 --- a/src/jetpac.s +++ b/src/jetpac.s @@ -153,9 +153,15 @@ sta Globals::zp_level and #%00000111 sta Globals::zp_level_kind + lda #LEVEL + and #%00001100 + lsr + lsr + sta Globals::zp_shuttle_kind .else sta Globals::zp_level sta Globals::zp_level_kind + sta Globals::zp_shuttle_kind .endif ;; Initialize the assets for the game. If the first sprite is not |