diff options
Diffstat (limited to 'src/player.s')
| -rw-r--r-- | src/player.s | 98 |
1 files changed, 87 insertions, 11 deletions
diff --git a/src/player.s b/src/player.s index af5572b..dc87cb0 100644 --- a/src/player.s +++ b/src/player.s @@ -61,15 +61,24 @@ ;; Flags that manage the state of the game. ;; - ;; | Bit | Short name | Meaning when set | - ;; |-----+------------+----------------------------------------------------------| - ;; | 7 | throttle | Player is hitting the throttle | - ;; | 6 | heading | heading right | - ;; | 5-3 | - | Unused | - ;; | 2 | update | Sprite (animation or heading) must be updated | - ;; | 1-0 | walk | 0: still; 1: animation 1; 2: animation 2, 3: animation 3 | + ;; | Bit | Short name | Meaning when set | + ;; |-----+------------+-----------------------------------------------| + ;; | 7 | throttle | Player is hitting the throttle | + ;; | 6 | heading | heading right | + ;; | 5-3 | - | Unused | + ;; | 2 | update | Sprite (animation or heading) must be updated | + ;; | 1-0 | walk | 0: still; 1: animation 1; 2: animation 2 | zp_state = $50 + ;; Simple counter for the walking animation. + zp_walk_counter = $51 + + ;; How many animations are there for walking? + WALK_ANIMATION_NR = 3 + + ;; How many frames are we allowing for each walk animation state? + WALK_COUNTER_MAX = (HZ / 10) + ;; Initialize the player's sprite. Note that for the sprite to look ;; correctly on screen you still need to call `Player::update` afterwards. .proc init @@ -77,12 +86,13 @@ lda #%01000100 sta zp_state - ;; Reset velocity + ;; Reset velocity and walking counter. lda #0 sta zp_target_velocity_y sta zp_velocity_y sta zp_target_velocity_x sta zp_velocity_x + sta zp_walk_counter ;; Set position, and the screen coordinates will be updated upong ;; calling `update`, which on initialization will happen right after. @@ -98,10 +108,56 @@ rts .endproc + ;; Call this function to update anything player-related. Ideally this should + ;; be called on each game iteration for the main screen, and after the + ;; controller has been read. .proc update + ;; Update both vertical and horizontal positions. jsr update_vertical_position jsr update_horizontal_position + ;; If throttling, then reset the walking counter and the walk state. + bit zp_state + bpl @walk_animation + lda #0 + sta zp_walk_counter + lda #%11111100 + and zp_state + sta zp_state + jmp @to_screen + + @walk_animation: + ;; If the player is not even moving, skip the animation. + lda zp_velocity_x + beq @to_screen + + ;; Increase the counter and check for its maximum value. + inc zp_walk_counter + lda zp_walk_counter + cmp #WALK_COUNTER_MAX + bne @to_screen + + ;; The counter has reached the maximum value. Increase the walk state. + lda zp_state + tax + and #%00000011 + clc + adc #1 + cmp #WALK_ANIMATION_NR + bne @set_animation + lda #0 + @set_animation: + sta Globals::zp_tmp0 + txa + and #%11111100 + ora Globals::zp_tmp0 + sta zp_state + + ;; And reset the counter. + lda #0 + sta zp_walk_counter + + @to_screen: ;; At this point all positions are clear, transform them into screen ;; coordinates, eject out from boundaries and platforms, and update the ;; sprite with the new state. @@ -424,8 +480,8 @@ lda #0 sta zp_velocity_y - ;; Set the player's state to grounded and with the still animation. - lda #%01111100 + ;; Set the player's state to grounded. + lda #%01111111 and zp_state ora #%00000100 sta zp_state @@ -465,10 +521,30 @@ ;; dealing with heading can rely on these two registers. bit zp_state bmi @throttle - ;; TODO: walk animation + + ;; The walking sprites depends on the current walking animation set on + ;; the player's state. + lda zp_state + and #%00000011 + cmp #1 + beq @animation1 + cmp #2 + beq @animation2 + ;; NOTE: fallthrough for either 0 or even buggy states. + @still: ldx #$21 ldy #$20 bne @heading + @animation1: + ldx #$02 + ldy #$20 + bne @heading + @animation2: + ldx #$13 + ldy #$12 + bne @heading + + ;; There's only one set for the throttle, no animations here. @throttle: ldx #$23 ldy #$22 |