diff options
Diffstat (limited to 'engine/overworld/movement.asm')
| -rw-r--r-- | engine/overworld/movement.asm | 341 |
1 files changed, 178 insertions, 163 deletions
diff --git a/engine/overworld/movement.asm b/engine/overworld/movement.asm index c4482700..be10fd69 100644 --- a/engine/overworld/movement.asm +++ b/engine/overworld/movement.asm @@ -12,7 +12,7 @@ UpdatePlayerSprite: ; 4e31 (1:4e31) ; the maximum number for map tiles .checkIfTextBoxInFrontOfSprite aCoord 8, 9 - ld [$ff93], a + ld [hTilePlayerStandingOn], a cp $60 jr c, .lowerLeftTileIsMapTile .disableSprite @@ -21,52 +21,54 @@ UpdatePlayerSprite: ; 4e31 (1:4e31) ret .lowerLeftTileIsMapTile call DetectCollisionBetweenSprites - ld h, $c1 - ld a, [wWalkCounter] ; wcfc5 + ld h, wSpriteStateData1 / $100 + ld a, [wWalkCounter] and a - jr nz, .asm_4e90 - ld a, [wd528] - bit 2, a - jr z, .asm_4e65 - xor a - jr .asm_4e86 -.asm_4e65 - bit 3, a - jr z, .asm_4e6d - ld a, $4 - jr .asm_4e86 -.asm_4e6d - bit 1, a - jr z, .asm_4e75 - ld a, $8 - jr .asm_4e86 -.asm_4e75 - bit 0, a - jr z, .asm_4e7d - ld a, $c - jr .asm_4e86 -.asm_4e7d + jr nz, .moving + ld a, [wPlayerMovingDirection] +; check if down + bit PLAYER_DIR_BIT_DOWN, a + jr z, .checkIfUp + xor a ; ld a, SPRITE_FACING_DOWN + jr .next +.checkIfUp + bit PLAYER_DIR_BIT_UP, a + jr z, .checkIfLeft + ld a, SPRITE_FACING_UP + jr .next +.checkIfLeft + bit PLAYER_DIR_BIT_LEFT, a + jr z, .checkIfRight + ld a, SPRITE_FACING_LEFT + jr .next +.checkIfRight + bit PLAYER_DIR_BIT_RIGHT, a + jr z, .notMoving + ld a, SPRITE_FACING_RIGHT + jr .next +.notMoving +; zero the animation counters xor a ld [wSpriteStateData1 + 7], a ld [wSpriteStateData1 + 8], a - jr .asm_4eab -.asm_4e86 - ld [wSpriteStateData1 + 9], a + jr .calcImageIndex +.next + ld [wSpriteStateData1 + 9], a ; facing direction ld a, [wFontLoaded] bit 0, a - jr nz, .asm_4e7d -.asm_4e90 + jr nz, .notMoving +.moving ld a, [wd736] - bit 7, a - jr nz, .asm_4eb6 + bit 7, a ; is the player sprite spinning due to a spin tile? + jr nz, .skipSpriteAnim ld a, [H_CURRENTSPRITEOFFSET] add $7 ld l, a ld a, [hl] inc a ld [hl], a - cp $4 - jr nz, .asm_4eab + cp 4 + jr nz, .calcImageIndex xor a ld [hl], a inc hl @@ -74,28 +76,32 @@ UpdatePlayerSprite: ; 4e31 (1:4e31) inc a and $3 ld [hl], a -.asm_4eab +.calcImageIndex ld a, [wSpriteStateData1 + 8] ld b, a ld a, [wSpriteStateData1 + 9] add b ld [wSpriteStateData1 + 2], a -.asm_4eb6 - ld a, [$ff93] +.skipSpriteAnim +; If the player is standing on a grass tile, make the player's sprite have +; lower priority than the background so that it's partially obscured by the +; grass. Only the lower half of the sprite is permitted to have the priority +; bit set by later logic. + ld a, [hTilePlayerStandingOn] ld c, a ld a, [W_GRASSTILE] cp c ld a, $0 - jr nz, .asm_4ec3 + jr nz, .next2 ld a, $80 -.asm_4ec3 +.next2 ld [wSpriteStateData2 + $07], a ret -Func_4ec7: ; 4ec7 (1:4ec7) +UnusedReadSpriteDataFunction: ; 4ec7 (1:4ec7) push bc push af - ld a, [$ffda] + ld a, [H_CURRENTSPRITEOFFSET] ld c, a pop af add c @@ -103,12 +109,12 @@ Func_4ec7: ; 4ec7 (1:4ec7) pop bc ret -Func_4ed1: ; 4ed1 (1:4ed1) +UpdateNPCSprite: ; 4ed1 (1:4ed1) ld a, [H_CURRENTSPRITEOFFSET] swap a dec a add a - ld hl, W_MAPSPRITEDATA ; wd4e4 + ld hl, W_MAPSPRITEDATA add l ld l, a ld a, [hl] ; read movement byte 2 @@ -138,7 +144,7 @@ Func_4ed1: ; 4ed1 (1:4ed1) jp z, UpdateSpriteMovementDelay ; c1x1 == 2 cp $3 jp z, UpdateSpriteInWalkingAnimation ; c1x1 == 3 - ld a, [wWalkCounter] ; wcfc5 + ld a, [wWalkCounter] and a ret nz ; don't do anything yet if player is currently moving (redundant, already tested in CheckSpriteAvailability) call InitializeSpriteScreenPosition @@ -148,40 +154,43 @@ Func_4ed1: ; 4ed1 (1:4ed1) ld l, a ld a, [hl] ; c2x6: movement byte 1 inc a - jr z, .asm_4f59 ; value $FF + jr z, .randomMovement ; value $FF inc a - jr z, .asm_4f59 ; value $FE + jr z, .randomMovement ; value $FE +; scripted movement dec a - ld [hl], a ; (temporarily) increment movement byte 1 + ld [hl], a ; increment movement byte 1 (movement data index) dec a push hl - ld hl, wcf0f - dec [hl] ; decrement wcf0f + ld hl, wNPCNumScriptedSteps + dec [hl] ; decrement wNPCNumScriptedSteps pop hl - ld de, wcc5b - call LoadDEPlusA ; a = [wcc5b + movement byte 1] + ld de, wNPCMovementDirections + call LoadDEPlusA ; a = [wNPCMovementDirections + movement byte 1] cp $e0 jp z, ChangeFacingDirection cp $ff - jr nz, .asm_4f4b - ld [hl], a ; reset movement byte 1 to initial value + jr nz, .next +; reached end of wNPCMovementDirections list + ld [hl], a ; store $ff in movement byte 1, disabling scripted movement ld hl, wd730 res 0, [hl] xor a ld [wSimulatedJoypadStatesIndex], a ld [wWastedByteCD3A], a ret -.asm_4f4b +.next cp $fe - jr nz, .asm_4f5f + jr nz, .determineDirection +; current NPC movement data is $fe. this seems buggy ld [hl], $1 ; set movement byte 1 to $1 - ld de, wcc5b - call LoadDEPlusA ; a = [wcc5b + $fe] (?) - jr .asm_4f5f -.asm_4f59 - call getTileSpriteStandsOn + ld de, wNPCMovementDirections + call LoadDEPlusA ; a = [wNPCMovementDirections + $fe] (?) + jr .determineDirection +.randomMovement + call GetTileSpriteStandsOn call Random -.asm_4f5f +.determineDirection ld b, a ld a, [wCurSpriteMovement2] cp $d0 @@ -199,11 +208,10 @@ Func_4ed1: ; 4ed1 (1:4ed1) cp $2 jr z, .moveLeft ; movement byte 2 = $2 only allows left or right .moveDown - ld de, 2*20 + ld de, 2*SCREEN_WIDTH add hl, de ; move tile pointer two rows down - ld de, $100 - - ld bc, $400 + lb de, 1, 0 + lb bc, 4, SPRITE_FACING_DOWN jr TryWalking .notDown cp $80 ; $40 <= a < $80: up (or right) @@ -212,10 +220,10 @@ Func_4ed1: ; 4ed1 (1:4ed1) cp $2 jr z, .moveRight ; movement byte 2 = $2 only allows left or right .moveUp - ld de, -2*20 ; $ffd8 + ld de, -2*SCREEN_WIDTH add hl, de ; move tile pointer two rows up - ld de, $ff00 - ld bc, $804 + lb de, -1, 0 + lb bc, 8, SPRITE_FACING_UP jr TryWalking .notUp cp $c0 ; $80 <= a < $c0: left (or up) @@ -226,8 +234,8 @@ Func_4ed1: ; 4ed1 (1:4ed1) .moveLeft dec hl dec hl ; move tile pointer two columns left - ld de, $ff - ld bc, $208 + lb de, 0, -1 + lb bc, 2, SPRITE_FACING_LEFT jr TryWalking .notLeft ; $c0 <= a: right (or down) ld a, [wCurSpriteMovement2] @@ -236,8 +244,8 @@ Func_4ed1: ; 4ed1 (1:4ed1) .moveRight inc hl inc hl ; move tile pointer two columns right - ld de, $1 - ld bc, $10c + lb de, 0, 1 + lb bc, 1, SPRITE_FACING_RIGHT jr TryWalking ; changes facing direction by zeroing the movement delta and calling TryWalking @@ -249,7 +257,7 @@ ChangeFacingDirection: ; 4fc8 (1:4fc8) ; c: new facing direction (0,4,8 or $c) ; d: Y movement delta (-1, 0 or 1) ; e: X movement delta (-1, 0 or 1) -; hl: pointer to tile the sprite would wlak onto +; hl: pointer to tile the sprite would walk onto ; set carry on failure, clears carry on success TryWalking: ; 4fcb (1:4fcb) push hl @@ -397,23 +405,23 @@ InitializeSpriteFacingDirection: ; 507f (1:507f) bit 5, a jr nz, notYetMoving res 7, [hl] - ld a, [wd52a] - bit 3, a + ld a, [wPlayerDirection] + bit PLAYER_DIR_BIT_UP, a jr z, .notFacingDown - ld c, $0 ; make sprite face down + ld c, SPRITE_FACING_DOWN jr .facingDirectionDetermined .notFacingDown - bit 2, a + bit PLAYER_DIR_BIT_DOWN, a jr z, .notFacingUp - ld c, $4 ; make sprite face up + ld c, SPRITE_FACING_UP jr .facingDirectionDetermined .notFacingUp - bit 1, a + bit PLAYER_DIR_BIT_LEFT, a jr z, .notFacingRight - ld c, $c ; make sprite face right + ld c, SPRITE_FACING_RIGHT jr .facingDirectionDetermined .notFacingRight - ld c, $8 ; make sprite face left + ld c, SPRITE_FACING_LEFT .facingDirectionDetermined ld a, [H_CURRENTSPRITEOFFSET] add $9 @@ -440,7 +448,7 @@ InitializeSpriteScreenPosition: ; 50bd (1:50bd) ld a, [H_CURRENTSPRITEOFFSET] add $4 ld l, a - ld a, [W_YCOORD] ; wd361 + ld a, [W_YCOORD] ld b, a ld a, [hl] ; c2x4 (Y position + 4) sub b ; relative to player position @@ -449,7 +457,7 @@ InitializeSpriteScreenPosition: ; 50bd (1:50bd) dec h ld [hli], a ; c1x4 (screen Y position) inc h - ld a, [W_XCOORD] ; wd362 + ld a, [W_XCOORD] ld b, a ld a, [hli] ; c2x6 (X position + 4) sub b ; relative to player position @@ -470,12 +478,12 @@ CheckSpriteAvailability: ; 50dc (1:50dc) ld l, a ld a, [hl] ; c2x6: movement byte 1 cp $fe - jr c, .skipXVisibilityTest ; movement byte 1 < $fe + jr c, .skipXVisibilityTest ; movement byte 1 < $fe (i.e. the sprite's movement is scripted) ld a, [H_CURRENTSPRITEOFFSET] add $4 ld l, a ld b, [hl] ; c2x4: Y pos (+4) - ld a, [W_YCOORD] ; wd361 + ld a, [W_YCOORD] cp b jr z, .skipYVisibilityTest jr nc, .spriteInvisible ; above screen region @@ -485,7 +493,7 @@ CheckSpriteAvailability: ; 50dc (1:50dc) .skipYVisibilityTest inc l ld b, [hl] ; c2x5: X pos (+4) - ld a, [W_XCOORD] ; wd362 + ld a, [W_XCOORD] cp b jr z, .skipXVisibilityTest jr nc, .spriteInvisible ; left of screen region @@ -495,7 +503,7 @@ CheckSpriteAvailability: ; 50dc (1:50dc) .skipXVisibilityTest ; make the sprite invisible if a text box is in front of it ; $5F is the maximum number for map tiles - call getTileSpriteStandsOn + call GetTileSpriteStandsOn ld d, $60 ld a, [hli] cp d @@ -503,7 +511,7 @@ CheckSpriteAvailability: ; 50dc (1:50dc) ld a, [hld] cp d jr nc, .spriteInvisible ; standing on tile with ID >=$60 (bottom right tile) - ld bc, -20 ; $ffec + ld bc, -20 add hl, bc ; go back one row of tiles ld a, [hli] cp d @@ -521,7 +529,7 @@ CheckSpriteAvailability: ; 50dc (1:50dc) jr .done .spriteVisible ld c, a - ld a, [wWalkCounter] ; wcfc5 + ld a, [wWalkCounter] and a jr nz, .done ; if player is currently walking, we're done call UpdateSpriteImage @@ -572,10 +580,11 @@ CanWalkOntoTile: ; 516e (1:516e) ld l, a ld a, [hl] ; c2x6 (movement byte 1) cp $fe - jr nc, .canMove ; values $fe and $ff + jr nc, .notScripted ; values $fe and $ff +; always allow walking if the movement is scripted and a ret -.canMove +.notScripted ld a, [W_TILESETCOLLISIONPTR] ld l, a ld a, [W_TILESETCOLLISIONPTR+1] @@ -675,7 +684,7 @@ CanWalkOntoTile: ; 516e (1:516e) ; calculates the tile pointer pointing to the tile the current sprite stancs on ; this is always the lower left tile of the 2x2 tile blocks all sprites are snapped to ; hl: output pointer -getTileSpriteStandsOn: ; 5207 (1:5207) +GetTileSpriteStandsOn: ; 5207 (1:5207) ld h, $c1 ld a, [H_CURRENTSPRITEOFFSET] add $4 @@ -690,11 +699,11 @@ getTileSpriteStandsOn: ; 5207 (1:5207) ld a, [hl] ; c1x6: screen Y position srl a srl a - srl a ; screen X tile - add $14 ; screen X tile + 20 + srl a ; screen X tile + add SCREEN_WIDTH ; screen X tile + 20 ld d, $0 ld e, a - ld hl, wTileMap + coord hl, 0, 0 add hl, bc add hl, bc add hl, bc @@ -713,53 +722,58 @@ LoadDEPlusA: ; 522f (1:522f) ld a, [de] ret -Func_5236: ; 5236 (1:5236) +DoScriptedNPCMovement: ; 5236 (1:5236) +; This is an alternative method of scripting an NPC's movement and is only used +; a few times in the game. It is used when the NPC and player must walk together +; in sync, such as when the player is following the NPC somewhere. An NPC can't +; be moved in sync with the player using the other method. ld a, [wd730] bit 7, a ret z ld hl, wd72e bit 7, [hl] set 7, [hl] - jp z, Func_52a6 + jp z, InitScriptedNPCMovement ld hl, wNPCMovementDirections2 ld a, [wNPCMovementDirections2Index] add l ld l, a - jr nc, .asm_5251 + jr nc, .noCarry inc h -.asm_5251 +.noCarry ld a, [hl] - cp $40 - jr nz, .asm_525f - call Func_52b2 - ld c, $4 - ld a, $fe - jr .asm_5289 -.asm_525f - cp $0 - jr nz, .asm_526c - call Func_52b2 - ld c, $0 - ld a, $2 - jr .asm_5289 -.asm_526c - cp $80 - jr nz, .asm_5279 - call Func_52b7 - ld c, $8 - ld a, $fe - jr .asm_5289 -.asm_5279 - cp $c0 - jr nz, .asm_5286 - call Func_52b7 - ld c, $c - ld a, $2 - jr .asm_5289 -.asm_5286 +; check if moving up + cp NPC_MOVEMENT_UP + jr nz, .checkIfMovingDown + call GetSpriteScreenYPointer + ld c, SPRITE_FACING_UP + ld a, -2 + jr .move +.checkIfMovingDown + cp NPC_MOVEMENT_DOWN + jr nz, .checkIfMovingLeft + call GetSpriteScreenYPointer + ld c, SPRITE_FACING_DOWN + ld a, 2 + jr .move +.checkIfMovingLeft + cp NPC_MOVEMENT_LEFT + jr nz, .checkIfMovingRight + call GetSpriteScreenXPointer + ld c, SPRITE_FACING_LEFT + ld a, -2 + jr .move +.checkIfMovingRight + cp NPC_MOVEMENT_RIGHT + jr nz, .noMatch + call GetSpriteScreenXPointer + ld c, SPRITE_FACING_RIGHT + ld a, 2 + jr .move +.noMatch cp $ff ret -.asm_5289 +.move ld b, a ld a, [hl] add b @@ -768,33 +782,34 @@ Func_5236: ; 5236 (1:5236) add $9 ld l, a ld a, c - ld [hl], a - call Func_52c3 - ld hl, wcf18 + ld [hl], a ; facing direction + call AnimScriptedNPCMovement + ld hl, wScriptedNPCWalkCounter dec [hl] ret nz - ld a, $8 - ld [wcf18], a + ld a, 8 + ld [wScriptedNPCWalkCounter], a ld hl, wNPCMovementDirections2Index inc [hl] ret -Func_52a6: ; 52a6 (1:52a6) +InitScriptedNPCMovement: ; 52a6 (1:52a6) xor a ld [wNPCMovementDirections2Index], a - ld a, $8 - ld [wcf18], a - jp Func_52c3 + ld a, 8 + ld [wScriptedNPCWalkCounter], a + jp AnimScriptedNPCMovement -Func_52b2: ; 52b2 (1:52b2) +GetSpriteScreenYPointer: ; 52b2 (1:52b2) ld a, $4 ld b, a - jr asm_52ba + jr GetSpriteScreenXYPointerCommon -Func_52b7: ; 52b7 (1:52b7) +GetSpriteScreenXPointer: ; 52b7 (1:52b7) ld a, $6 ld b, a -asm_52ba: ; 52ba (1:52ba) + +GetSpriteScreenXYPointerCommon: ; 52ba (1:52ba) ld hl, wSpriteStateData1 ld a, [H_CURRENTSPRITEOFFSET] add l @@ -802,12 +817,12 @@ asm_52ba: ; 52ba (1:52ba) ld l, a ret -Func_52c3: ; 52c3 (1:52c3) +AnimScriptedNPCMovement: ; 52c3 (1:52c3) ld hl, wSpriteStateData2 ld a, [H_CURRENTSPRITEOFFSET] add $e ld l, a - ld a, [hl] + ld a, [hl] ; VRAM slot dec a swap a ld b, a @@ -815,47 +830,47 @@ Func_52c3: ; 52c3 (1:52c3) ld a, [H_CURRENTSPRITEOFFSET] add $9 ld l, a - ld a, [hl] - cp $0 - jr z, .asm_52ea - cp $4 - jr z, .asm_52ea - cp $8 - jr z, .asm_52ea - cp $c - jr z, .asm_52ea + ld a, [hl] ; facing direction + cp SPRITE_FACING_DOWN + jr z, .anim + cp SPRITE_FACING_UP + jr z, .anim + cp SPRITE_FACING_LEFT + jr z, .anim + cp SPRITE_FACING_RIGHT + jr z, .anim ret -.asm_52ea +.anim add b ld b, a - ld [$ffe9], a - call Func_5301 + ld [hSpriteVRAMSlotAndFacing], a + call AdvanceScriptedNPCAnimFrameCounter ld hl, wSpriteStateData1 ld a, [H_CURRENTSPRITEOFFSET] add $2 ld l, a - ld a, [$ffe9] + ld a, [hSpriteVRAMSlotAndFacing] ld b, a - ld a, [$ffea] + ld a, [hSpriteAnimFrameCounter] add b ld [hl], a ret -Func_5301: ; 5301 (1:5301) +AdvanceScriptedNPCAnimFrameCounter: ; 5301 (1:5301) ld a, [H_CURRENTSPRITEOFFSET] add $7 ld l, a - ld a, [hl] + ld a, [hl] ; intra-animation frame counter inc a ld [hl], a - cp $4 + cp 4 ret nz xor a - ld [hl], a + ld [hl], a ; reset intra-animation frame counter inc l - ld a, [hl] + ld a, [hl] ; animation frame counter inc a and $3 ld [hl], a - ld [$ffea], a + ld [hSpriteAnimFrameCounter], a ret |