cleaned up animation code + fixed frame 0 bug

src/animation.asm

@@ -7,8 +7,8 @@
    bytes 1, XPos
    bytes 1, GFXCounter
    bytes 1, GFXState
-   words 1, GFXData
    bytes 1, TileData
+   words 1, GFXData
    end_struct
 
 SECTION "Actor STructs", WRAM0
@@ -28,7 +28,6 @@ hWorkingState: db
 hWorkingCounter: db
 hWorkingData: dw
 hWorkingTile: db
-hWorkingEnd:
 
 SECTION "Animations Subs", ROM0
 
@@ -47,117 +46,105 @@ SECTION "Animations Subs", ROM0
 RenderActor::
    ; @input: hl <- Player
    ; @input: de <- ShadowOAM place
-   ld a, [hli] ; a <- YPos
+   ; clobbers af, bc, de, hl
+   
+   ld a, [hli]                                  ; a <- YPos
    ldh [hWorkingScreenY], a
-   ld a, [hli] ; a <- XPos
+   ld a, [hli]                                  ; a <- XPos
    ldh [hWorkingScreenX], a
-   push hl
-   ld a, [hli] ; a <- GFXCounter
+   push hl                                      ; save counter pointer on stack
+   ld a, [hli]                                  ; a <- GFXCounter
    ldh [hWorkingCounter], a
-   ld a, [hli] ; a <- GFXState
+   ld a, [hli]                                  ; a <- GFXState
    ldh [hWorkingState], a
-   ld a, [hli] ; a <- GFXData(Low)
-   ldh [hWorkingData+1], a
-   ld a, [hli] ; a <- GFXData (High)
-   ldh [hWorkingData], a
-   ld a, [hl] ; a <- TileData
+   ld a, [hli]                                  ; a <- TileData
    ldh [hWorkingTile], a
-; fin loading data
-   ld a, [hWorkingData]
+   ld a, [hli]                                  ; a <- GFXData(Low)
+   ld h, [hl]                                   ; a <- GFXData (High)
    ld l, a
-   ld a, [hWorkingData+1]
-   ld h, a
-; add actor struct offset saved in wWorkingState
-   ld a, [hWorkingState]
-   rlca                  ; double state offset because of word length
+
+   ld a, [hWorkingState]                        ; add actor struct offset saved in wWorkingState
+   rlca                                         ; double state offset because of word length
    add a, l
    ld l, a
    adc a, h
    sub l
-   ld h, a               ; hl contains state struct pointer
-   ld a, [hli]
-   ld b, a
-   ld a, [hl]
-   ld l, b
-   ld h, a
-   ld a, [hli]           ; a <- state frame limit
-   ld b, a
+   ld h, a                                      ; hl contains state struct pointer
+
+   ld a, [hli]                                  ;
+   ld h, [hl]                                   ; derefence [hl]
+   ld l, a                                      ;
+
    ld a, [hWorkingCounter]
    inc a
-   ld c, a
-   ld a, b
-   ld b, c
+   ld b, a
+   ld a, [hli]                                  ; a <- state frame limit
    cp b
    ld a, b
    jr nc, .continueAnimation
    xor a
 .continueAnimation
-   ; TODO: make counter 0 indexed so doesnt skip first frame
    ldh [hWorkingCounter], a
-   ld b, h
-   ld c, l
-   pop hl
-   ld [hl], a
-   ld h, b
-   ld l, c
-.loopFrameFind
-   ld b, a      ; b <- current frame count
-   ld a, [hli]  ; a <- next frame block
-   ld c, a
-   ld a, b
-   ld b, c
-   sub b
-   jr z, .foundFrame
-   jr c, .foundFrame
+   ld b, h                                      ;
+   ld c, l                                      ; save current hl
+   pop hl                                       ; restore counter wram pointer
+   ld [hl], a                                   ;
+   ld h, b                                      ; restore hl
+   ld l, c                                      ;
+
+   ld c, a                                      ; save current frame in c
+   xor a                                        ; set a = 0
+.loopFrameFind                                  ; 
+   ld b, a                                      ; b <- current total
+   ld a, [hli]                                  ; a <- next frame tick limit
+   add b                                        ; add to limit
+   cp c                                         ; compare to limit
+   jr nc, .foundFrame                           ; if no carry, cum total > current frame
    inc hl
    inc hl
    jr .loopFrameFind
+
 .foundFrame
    ld a, [hli]
-   ld b, a
-   ld a, [hl]
-   ld h, a
-   ld l, b     ; hl <- pointer to frame data
+   ld h, [hl]
+   ld l, a                                      ; hl <- pointer to frame data
    ld a, [hli]
-   ld b, a     ; b <- sprite counter
+   ld b, a                                      ; b <- sprite counter
+
 .spriteLoop
-   ; load Y position, then offset by -16
-   ld a, [hli]
+
+   ld a, [hli]                                  ; load Y position, then offset by -16
    ld c, a
    ld a, [hWorkingScreenY]
    add c
    ld c, 16
    add c
-   ld [de], a          ; store YPos in shadowOAM
+   ld [de], a                                   ; store YPos in shadowOAM
    inc de
-   ; load X position, then offset by -8
-   ld a, [hli]
+   
+   ld a, [hli]                                  ; load X position, then offset by -8
    ld c, a
    ld a, [hWorkingScreenX]
    add c
    ld c, 8
    add c
-   ld [de], a          ; store YPos in shadowOAM
+   ld [de], a                                   ; store XPos in shadowOAM
    inc de
-   ; load tile offset, and add to base tile pointer
-   ld a, [hli]
+
+   ld a, [hli]                                  ; load tile offset, and add to base tile pointer
    ld c, a
    ld a, [hWorkingTile]
    add c
    ld [de], a
    inc de
-   ; load attributes and xor them
-   ld a, [hli]
+
+   ld a, [hli]                                  ; load attributes and xor them
    ld c, a
-   ld a, 0    ; TO DO: set base attributes
+   ld a, 0                                      ; TO DO: set base attributes
    xor c
    ld [de], a
    inc de
-   ; end of single sprite
-   dec b
+   
+   dec b                                        ; end of single sprite
    jr nz, .spriteLoop
    ret
-
-BUFFER       EQU 160
-TRUE         EQU $42
-FALSE        EQU $69

src/entry.asm

@@ -33,14 +33,15 @@ Start:
    ld [Player_YPos], a
    ld a, 80
    ld [Player_XPos], a
-   xor a
+   ld a, $FF
    ld [Player_GFXCounter], a
+   xor a
    ld [Player_GFXState], a
    ld [Player_TileData], a
    ld a, HIGH(ActorROM)
-   ld [Player_GFXData], a
+   ld [Player_GFXData+1], a
    ld a, LOW(ActorROM)
-   ld [Player_GFXData + 1], a
+   ld [Player_GFXData], a
 
    ld a, LCDCF_ON | LCDCF_OBJON | LCDCF_BGON
    ld [rLCDC], a