diff options
Diffstat (limited to 'src/driver.s')
| -rw-r--r-- | src/driver.s | 89 |
1 files changed, 80 insertions, 9 deletions
diff --git a/src/driver.s b/src/driver.s index 8d6ee52..8a0d452 100644 --- a/src/driver.s +++ b/src/driver.s @@ -2,12 +2,18 @@ .scope Driver ;; Timer for the player to be able to pick up the joypad upon entering the - ;; game. + ;; game (either when transitioning from the title or when losing a life). ;; ;; NOTE: this memory address is shared with `zp_title_timer`, as they can ;; never conflict with each other. zp_player_timer = $30 ; asan:ignore - PLAYER_TIMER_VALUE = HZ * 2 + PLAYER_TIMER_FULL_VALUE = HZ * 3 + PLAYER_TIMER_DEV_VALUE = HZ / 2 + .ifdef PARTIAL + PLAYER_TIMER_VALUE = PLAYER_TIMER_DEV_VALUE + .else + PLAYER_TIMER_VALUE = PLAYER_TIMER_FULL_VALUE + .endif .ifdef PAL ;; Frame counter which resets every 5 frames. @@ -32,6 +38,12 @@ ;; Same as `zp_next_bullet_cycle` but for enemies. zp_next_enemy_cycle = $37 + ;; Whether sprites have already been moved out in the 'move_sprites_out' + ;; situation. It's probably a waste of resources to spend a full byte for + ;; this, but I didn't see where to put it either, and we still have plenty + ;; of RAM left. + zp_moved_out = $38 + ;; Switch from the title screen to the main screen. Note that this function ;; is to be called with the PPU disabled. If that's not the case, then it ;; will set the proper values to disable it on the next `nmi` call and set @@ -65,11 +77,7 @@ sta PPU::zp_mask ;; Setup the player timer. - .ifdef PARTIAL - lda #1 - .else - lda #PLAYER_TIMER_VALUE - .endif + lda #PLAYER_TIMER_VALUE sta zp_player_timer ;; Mark the state of the game as "game". That is, the player has @@ -82,14 +90,48 @@ rts .endproc + ;; Move enemies and bullets out of the screen. This is done by setting the + ;; 'inactive' state for each object. + .proc move_sprites_out + ldx #0 + lda #$FF + + ;; Invalidate all enemies. + ldy #Enemies::ENEMIES_POOL_CAPACITY + @enemies_reset_loop: + sta Enemies::zp_enemies_pool_base, x + NEXT_ENEMY_INDEX_X + dey + bne @enemies_reset_loop + + ;; Invalidate all bullets. + ldy #Bullets::BULLETS_POOL_CAPACITY + @bullets_reset_loop: + sta Bullets::zp_bullets_pool_base, x + NEXT_BULLET_INDEX_X + dey + bne @bullets_reset_loop + + ;; Set that we have done this operation so it's not done in future + ;; cycles. + lda #1 + sta Driver::zp_moved_out + + rts + .endproc + .proc update + ;; If the player timer is over, jump to the game immediately. Otherwise + ;; decrement the counter. lda zp_player_timer beq @game dec zp_player_timer beq @load_player + ;; TODO: items falling down. ;; TODO: blinking of the selected player (every HZ count?). + rts @load_player: @@ -98,15 +140,22 @@ jsr Enemies::init jsr Explosions::init - ;; Initialize pause timer. + ;; Initialize pause timer and whether sprites have been moved out of the + ;; screen. lda #0 sta zp_pause_timer + sta Driver::zp_moved_out ;; Initialize variables for sprite cycling. sta zp_next_bullet_cycle sta zp_next_enemy_cycle @game: + ;; Has the player died? + lda Globals::zp_flags + and #$10 + bne @do_minimal_update + ;; Check if the player is toggling the `pause` state. lda #(Joypad::BUTTON_START | Joypad::BUTTON_SELECT) and Joypad::zp_buttons1 @@ -158,10 +207,32 @@ jsr Player::update jsr Bullets::update jsr Enemies::update + @do_minimal_update: jsr Explosions::update - ;; TODO: check if player has died + ;; Has the player died? If it is dead, then we need to remove all + ;; sprites except for objects and explosions, and whenever + ;; explosions/items are done moving we can set the timer again to start + ;; over with the game screen. + lda Globals::zp_flags + and #$10 + beq @sprite_cycling + + ;; Invalidate bullets and enemies if we haven't already. + lda Driver::zp_moved_out + bne @check_explosions + jsr move_sprites_out + + @check_explosions: + ;; Are there still active explosions? + lda Explosions::zp_active + bne @sprite_cycling + + ;; Nope! Then set the player's timer. + lda #PLAYER_TIMER_VALUE + sta zp_player_timer + @sprite_cycling: __fallthrough__ sprite_cycling .endproc |