1.1 --- a/plotting.oph	Sun Mar 30 23:06:08 2014 +0200
     1.2 +++ b/plotting.oph	Sun Mar 30 23:39:32 2014 +0200
     1.3 @@ -63,14 +63,7 @@
     1.4  read_screen_address_bank1:  ; X=row, A=column offset
     1.5                              ; sets $72,$73
     1.6  
     1.7 -    asl                     ; Multiply o by 8
     1.8 -    asl
     1.9 -    asl
    1.10 -    sta $72
    1.11 -    lda #0
    1.12 -    adc #0
    1.13 -    sta $73
    1.14 -    clc
    1.15 +    jsr read_screen_address_low
    1.16  
    1.17      lda $72
    1.18      adc banks_rows_low,x    ; Add to the screen start address for the
    1.19 @@ -82,8 +75,7 @@
    1.20  
    1.21      rts
    1.22  
    1.23 -read_screen_address_bank2:  ; X=row, A=column offset
    1.24 -                            ; sets $72,$73=screen address
    1.25 +read_screen_address_low:
    1.26  
    1.27      asl                     ; Multiply o by 8
    1.28      asl
    1.29 @@ -93,6 +85,12 @@
    1.30      adc #0
    1.31      sta $73
    1.32      clc
    1.33 +    rts
    1.34 +
    1.35 +read_screen_address_bank2:  ; X=row, A=column offset
    1.36 +                            ; sets $72,$73=screen address
    1.37 +
    1.38 +    jsr read_screen_address_low
    1.39  
    1.40      lda $72
    1.41      adc banks_rows_low,x    ; Add to the screen start address for the
    1.42 @@ -110,13 +108,9 @@
    1.43      cmp #$10
    1.44      bcc read_sprite_address_next
    1.45  
    1.46 -    jsr read_visible_sprite     ; check whether the sprite is visible
    1.47 -                                ; (it represents a special tile)
    1.48 -
    1.49 -    and #$1f
    1.50 +    jsr read_and_mask_visible_sprite
    1.51  
    1.52      read_sprite_address_next:   ; a regular tile
    1.53 -    clc
    1.54  
    1.55      asl
    1.56      asl
    1.57 @@ -130,18 +124,23 @@
    1.58      clc
    1.59      rts
    1.60  
    1.61 +read_and_mask_visible_sprite:
    1.62 +
    1.63 +    jsr read_visible_sprite     ; check whether the sprite is visible
    1.64 +                                ; (it represents a special tile)
    1.65 +    and #$1f
    1.66 +    clc
    1.67 +    rts
    1.68 +
    1.69  read_left_sprite_address:       ; A=tile number
    1.70                                  ; sets $70,$71=sprite address
    1.71  
    1.72      cmp #$10
    1.73      bcc read_left_sprite_address_next
    1.74  
    1.75 -    jsr read_visible_sprite     ; check whether the sprite is visible
    1.76 -                                ; (it represents a special tile)
    1.77 -    and #$1f
    1.78 +    jsr read_and_mask_visible_sprite
    1.79  
    1.80      read_left_sprite_address_next:  ; a regular tile
    1.81 -    clc
    1.82  
    1.83      asl
    1.84      asl
    1.85 @@ -161,12 +160,9 @@
    1.86      cmp #$10
    1.87      bcc read_rotated_sprite_address_next
    1.88  
    1.89 -    jsr read_visible_sprite     ; check whether the sprite is visible
    1.90 -                                ; (it represents a special tile)
    1.91 -    and #$1f
    1.92 +    jsr read_and_mask_visible_sprite
    1.93  
    1.94      read_rotated_sprite_address_next:   ; a regular tile
    1.95 -    clc
    1.96  
    1.97      asl
    1.98      asl
    1.99 @@ -186,12 +182,9 @@
   1.100      cmp #$10
   1.101      bcc read_right_sprite_address_next
   1.102  
   1.103 -    jsr read_visible_sprite     ; check whether the sprite is visible
   1.104 -                                ; (it represents a special tile)
   1.105 -    and #$1f
   1.106 +    jsr read_and_mask_visible_sprite
   1.107  
   1.108      read_right_sprite_address_next: ; a regular tile
   1.109 -    clc
   1.110  
   1.111      asl
   1.112      asl

     2.1 --- a/sound.oph	Sun Mar 30 23:06:08 2014 +0200
     2.2 +++ b/sound.oph	Sun Mar 30 23:39:32 2014 +0200
     2.3 @@ -13,11 +13,7 @@
     2.4  ; You should have received a copy of the GNU General Public License
     2.5  ; along with this program.  If not, see <http://www.gnu.org/licenses/>.
     2.6  
     2.7 -sounds_low:  .byte <demise_sound, <item_sound, <jump_sound, <step_sound
     2.8 -             .byte <door_sound, <portal_sound
     2.9 -sounds_high: .byte >demise_sound, >item_sound, >jump_sound, >step_sound
    2.10 -             .byte >door_sound, >portal_sound
    2.11 -
    2.12 +sounds:
    2.13  demise_sound:   .byte 1,0, 1,0, 160,0, 6,0      ; 6 * 50ms
    2.14  item_sound:     .byte $13,0, 2,0, 160,0, 4,0    ; 4 * 50ms
    2.15  jump_sound:     .byte $13,0, 3,0, 50,0, 2,0     ; 2 * 50ms
    2.16 @@ -27,10 +23,16 @@
    2.17  
    2.18  play_sound:     ; X=sound number
    2.19  
    2.20 -    lda sounds_high,x
    2.21 +    txa
    2.22 +    asl
    2.23 +    asl
    2.24 +    asl
    2.25 +    adc #<sounds
    2.26 +    tax
    2.27 +    lda #0
    2.28 +    adc #>sounds
    2.29      tay
    2.30 -    lda sounds_low,x
    2.31 -    tax
    2.32 +    clc
    2.33      lda #7
    2.34      jsr $fff1
    2.35