diff options
| -rw-r--r-- | src/driver.s | 41 |
1 files changed, 22 insertions, 19 deletions
diff --git a/src/driver.s b/src/driver.s index c428475..66846ac 100644 --- a/src/driver.s +++ b/src/driver.s @@ -18,10 +18,9 @@ PAUSE_TIMER_VALUE = (HZ / 3) zp_pause_timer = $32 - ;; Number of sprites available for sprite cycling. - SPRITE_CYCLING_BYTES = (64 - Player::PLAYER_SPRITES_COUNT) * 4 - - ;; TODO + ;; Index from the pool of bullets from which the sprite cycling function + ;; will start on. This is constantly rotating so all bullets have at least + ;; the chance to have the highest priority every now and then. zp_next_bullet_cycle = $33 ;; Switch from the title screen to the main screen. Note that this function @@ -209,16 +208,16 @@ stx zp_next_bullet_cycle ;; TODO: ensure 1 enemy - iny - iny - iny - iny + ;; iny + ;; iny + ;; iny + ;; iny ;; TODO: ensure 1 item - iny - iny - iny - iny + ;; iny + ;; iny + ;; iny + ;; iny ;; TODO: rest of bullets ldx #0 @@ -276,21 +275,25 @@ ;; TODO: rest of enemies ;; TODO: rest of items - ;; We are done with all the sprites we wanted to allocat. Now let's + ;; Are all spots already filled? As in, did the 'y' register wrap + ;; around? If so, just go to the end. + tya + beq @end + + ;; We are done with all the sprites we wanted to allocate. Now let's ;; clear out the rest of the slots just in case there was some leftover - ;; from a past sprite. + ;; from a past sprite. Since the OAM space is 256 bytes long, we just + ;; need for the 'y' register to wrap around in order to quit. lda #$EF - @check_cycle_end: - cpy #SPRITE_CYCLING_BYTES - bne @reset_sprite - rts @reset_sprite: sta $200, y iny iny iny iny - jmp @check_cycle_end ;TODO: maybe just bne? + bne @reset_sprite + @end: + rts .endproc .ifdef PAL |