BlankScreen: call DisableSpriteUpdates xor a ldh [hBGMapMode], a call ClearBGPalettes call ClearSprites hlcoord 0, 0 ld bc, wTilemapEnd - wTilemap ld a, " " call ByteFill hlcoord 0, 0, wAttrmap ld bc, wAttrmapEnd - wAttrmap ld a, $7 call ByteFill call WaitBGMap2 call SetDefaultBGPAndOBP ret SpawnPlayer: ld a, -1 ld [wObjectFollow_Leader], a ld [wObjectFollow_Follower], a ld a, PLAYER ld hl, PlayerObjectTemplate call CopyPlayerObjectTemplate ld b, PLAYER call PlayerSpawn_ConvertCoords ld a, PLAYER_OBJECT call GetMapObject ld hl, MAPOBJECT_PALETTE add hl, bc push hl ld a, [wPlayerCharacter] ld e, PLAYERDATA_OW_PAL call GetPlayerField add PAL_NPC ; convert from PAL_OW to PAL_NPC swap a or OBJECTTYPE_SCRIPT pop hl ld [hl], a ld a, PLAYER_OBJECT ldh [hMapObjectIndex], a ld bc, wMapObjects ld a, PLAYER_OBJECT ldh [hObjectStructIndex], a ld de, wObjectStructs call CopyMapObjectToObjectStruct ld a, PLAYER ld [wCenteredObject], a ret PlayerObjectTemplate: ; A dummy map object used to initialize the player object. ; Shorter than the actual amount copied by two bytes. ; Said bytes seem to be unused. object_event -4, -4, SPRITE_CHRIS, SPRITEMOVEDATA_PLAYER, 15, 15, -1, -1, 0, OBJECTTYPE_SCRIPT, 0, 0, -1 CopyDECoordsToMapObject:: push de ld a, b call GetMapObject pop de ld hl, MAPOBJECT_X_COORD add hl, bc ld [hl], d ld hl, MAPOBJECT_Y_COORD add hl, bc ld [hl], e ret PlayerSpawn_ConvertCoords: push bc ld a, [wXCoord] add 4 ld d, a ld a, [wYCoord] add 4 ld e, a pop bc call CopyDECoordsToMapObject ret WriteObjectXY:: ld a, b call CheckObjectVisibility ret c ld hl, OBJECT_MAP_X add hl, bc ld d, [hl] ld hl, OBJECT_MAP_Y add hl, bc ld e, [hl] ldh a, [hMapObjectIndex] ld b, a call CopyDECoordsToMapObject and a ret RefreshPlayerCoords:: ld a, [wXCoord] add 4 ld d, a ld hl, wPlayerMapX sub [hl] ld [hl], d ld hl, wMapObjects + MAPOBJECT_X_COORD ld [hl], d ld hl, wPlayerLastMapX ld [hl], d ld d, a ld a, [wYCoord] add 4 ld e, a ld hl, wPlayerMapY sub [hl] ld [hl], e ld hl, wMapObjects + MAPOBJECT_Y_COORD ld [hl], e ld hl, wPlayerLastMapY ld [hl], e ld e, a ; the next three lines are useless ld a, [wObjectFollow_Leader] cp PLAYER ret nz ret CopyObjectStruct:: call CheckObjectMask and a ret nz ; masked ld hl, wObjectStructs + OBJECT_LENGTH * 1 ld a, 1 ld de, OBJECT_LENGTH .loop ldh [hObjectStructIndex], a ld a, [hl] and a jr z, .done add hl, de ldh a, [hObjectStructIndex] inc a cp NUM_OBJECT_STRUCTS jr nz, .loop scf ret ; overflow .done ld d, h ld e, l call CopyMapObjectToObjectStruct ld hl, wStateFlags bit 7, [hl] ret z ld hl, OBJECT_FLAGS2 add hl, de set 5, [hl] ret CopyMapObjectToObjectStruct: call .CopyMapObjectToTempObject call CopyTempObjectToObjectStruct ret .CopyMapObjectToTempObject: ldh a, [hObjectStructIndex] ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld [hl], a ldh a, [hMapObjectIndex] ld [wTempObjectCopyMapObjectIndex], a ld hl, MAPOBJECT_SPRITE add hl, bc ld a, [hl] ld [wTempObjectCopySprite], a call GetSpriteVTile ld [wTempObjectCopySpriteVTile], a ld a, [hl] call GetSpritePalette ld [wTempObjectCopyPalette], a ld hl, MAPOBJECT_PALETTE add hl, bc ld a, [hl] and MAPOBJECT_PALETTE_MASK jr z, .skip_color_override swap a and PALETTE_MASK ld [wTempObjectCopyPalette], a .skip_color_override ld hl, MAPOBJECT_MOVEMENT add hl, bc ld a, [hl] ld [wTempObjectCopyMovement], a ld hl, MAPOBJECT_SIGHT_RANGE add hl, bc ld a, [hl] ld [wTempObjectCopyRange], a ld hl, MAPOBJECT_X_COORD add hl, bc ld a, [hl] ld [wTempObjectCopyX], a ld hl, MAPOBJECT_Y_COORD add hl, bc ld a, [hl] ld [wTempObjectCopyY], a ld hl, MAPOBJECT_RADIUS add hl, bc ld a, [hl] ld [wTempObjectCopyRadius], a ret InitializeVisibleSprites: ld bc, wMapObject1 ld a, 1 .loop ldh [hMapObjectIndex], a ld hl, MAPOBJECT_SPRITE add hl, bc ld a, [hl] and a jr z, .next ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] cp -1 jr nz, .next ld a, [wXCoord] ld d, a ld a, [wYCoord] ld e, a ld hl, MAPOBJECT_X_COORD add hl, bc ld a, [hl] add 1 sub d jr c, .next cp MAPOBJECT_SCREEN_WIDTH jr nc, .next ld hl, MAPOBJECT_Y_COORD add hl, bc ld a, [hl] add 1 sub e jr c, .next cp MAPOBJECT_SCREEN_HEIGHT jr nc, .next push bc call CopyObjectStruct pop bc jp c, .ret .next ld hl, MAPOBJECT_LENGTH add hl, bc ld b, h ld c, l ldh a, [hMapObjectIndex] inc a cp NUM_OBJECTS jr nz, .loop ret .ret ret CheckObjectEnteringVisibleRange:: nop ld a, [wPlayerStepDirection] cp STANDING ret z ld hl, .dw rst JumpTable ret .dw dw .Down dw .Up dw .Left dw .Right .Up: ld a, [wYCoord] sub 1 jr .Vertical .Down: ld a, [wYCoord] add 9 .Vertical: ld d, a ld a, [wXCoord] ld e, a ld bc, wMapObject1 ld a, 1 .loop_v ldh [hMapObjectIndex], a ld hl, MAPOBJECT_SPRITE add hl, bc ld a, [hl] and a jr z, .next_v ld hl, MAPOBJECT_Y_COORD add hl, bc ld a, d cp [hl] jr nz, .next_v ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] cp -1 jr nz, .next_v ld hl, MAPOBJECT_X_COORD add hl, bc ld a, [hl] add 1 sub e jr c, .next_v cp MAPOBJECT_SCREEN_WIDTH jr nc, .next_v push de push bc call CopyObjectStruct pop bc pop de .next_v ld hl, MAPOBJECT_LENGTH add hl, bc ld b, h ld c, l ldh a, [hMapObjectIndex] inc a cp NUM_OBJECTS jr nz, .loop_v ret .Left: ld a, [wXCoord] sub 1 jr .Horizontal .Right: ld a, [wXCoord] add 10 .Horizontal: ld e, a ld a, [wYCoord] ld d, a ld bc, wMapObject1 ld a, 1 .loop_h ldh [hMapObjectIndex], a ld hl, MAPOBJECT_SPRITE add hl, bc ld a, [hl] and a jr z, .next_h ld hl, MAPOBJECT_X_COORD add hl, bc ld a, e cp [hl] jr nz, .next_h ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] cp -1 jr nz, .next_h ld hl, MAPOBJECT_Y_COORD add hl, bc ld a, [hl] add 1 sub d jr c, .next_h cp MAPOBJECT_SCREEN_HEIGHT jr nc, .next_h push de push bc call CopyObjectStruct pop bc pop de .next_h ld hl, MAPOBJECT_LENGTH add hl, bc ld b, h ld c, l ldh a, [hMapObjectIndex] inc a cp NUM_OBJECTS jr nz, .loop_h ret CopyTempObjectToObjectStruct: ld a, [wTempObjectCopyMapObjectIndex] ld hl, OBJECT_MAP_OBJECT_INDEX add hl, de ld [hl], a ld a, [wTempObjectCopyMovement] call CopySpriteMovementData ld a, [wTempObjectCopyPalette] ld hl, OBJECT_PALETTE add hl, de or [hl] ld [hl], a ld a, [wTempObjectCopyY] call .InitYCoord ld a, [wTempObjectCopyX] call .InitXCoord ld a, [wTempObjectCopySprite] ld hl, OBJECT_SPRITE add hl, de ld [hl], a ld a, [wTempObjectCopySpriteVTile] ld hl, OBJECT_SPRITE_TILE add hl, de ld [hl], a ld hl, OBJECT_STEP_TYPE add hl, de ld [hl], STEP_TYPE_RESET ld hl, OBJECT_FACING add hl, de ld [hl], STANDING ld a, [wTempObjectCopyRadius] call .InitRadius ld a, [wTempObjectCopyRange] ld hl, OBJECT_RANGE add hl, de ld [hl], a and a ret .InitYCoord: ld hl, OBJECT_INIT_Y add hl, de ld [hl], a ld hl, OBJECT_MAP_Y add hl, de ld [hl], a ld hl, wYCoord sub [hl] and $f swap a ld hl, wPlayerBGMapOffsetY sub [hl] ld hl, OBJECT_SPRITE_Y add hl, de ld [hl], a ret .InitXCoord: ld hl, OBJECT_INIT_X add hl, de ld [hl], a ld hl, OBJECT_MAP_X add hl, de ld [hl], a ld hl, wXCoord sub [hl] and $f swap a ld hl, wPlayerBGMapOffsetX sub [hl] ld hl, OBJECT_SPRITE_X add hl, de ld [hl], a ret .InitRadius: ld h, a inc a and $f ld l, a ld a, h add $10 and $f0 or l ld hl, OBJECT_RADIUS add hl, de ld [hl], a ret TrainerOrTalkerWalkToPlayer: ldh a, [hLastTalked] call InitMovementBuffer ld a, movement_step_sleep call AppendToMovementBuffer ld a, [wSeenTrainerOrTalkerDistance] dec a jr z, .TerminateStep ldh a, [hLastTalked] ld b, a ld c, PLAYER ld d, 1 call .GetPathToPlayer call DecrementMovementBufferCount .TerminateStep: ld a, movement_step_end call AppendToMovementBuffer ret .GetPathToPlayer: push de push bc ; get player object struct, load to de ld a, c call GetMapObject ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] call GetObjectStruct ld d, b ld e, c ; get last talked object struct, load to bc pop bc ld a, b call GetMapObject ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] call GetObjectStruct ; get last talked coords, load to bc ld hl, OBJECT_MAP_X add hl, bc ld a, [hl] ld hl, OBJECT_MAP_Y add hl, bc ld c, [hl] ld b, a ; get player coords, load to de ld hl, OBJECT_MAP_X add hl, de ld a, [hl] ld hl, OBJECT_MAP_Y add hl, de ld e, [hl] ld d, a pop af call ComputePathToWalkToPlayer ret SurfStartStep: call InitMovementBuffer call .GetMovementData call AppendToMovementBuffer ld a, movement_step_end call AppendToMovementBuffer ret .GetMovementData: ld a, [wPlayerDirection] srl a srl a maskbits NUM_DIRECTIONS ld e, a ld d, 0 ld hl, .movement_data add hl, de ld a, [hl] ret .movement_data slow_step DOWN slow_step UP slow_step LEFT slow_step RIGHT FollowNotExact:: push bc ld a, c call CheckObjectVisibility ld d, b ld e, c pop bc ret c ld a, b call CheckObjectVisibility ret c ; object 2 is now in bc, object 1 is now in de ld hl, OBJECT_MAP_X add hl, bc ld a, [hl] ld hl, OBJECT_MAP_Y add hl, bc ld c, [hl] ld b, a ld hl, OBJECT_MAP_X add hl, de ld a, [hl] cp b jr z, .same_x jr c, .to_the_left inc b jr .continue .to_the_left dec b jr .continue .same_x ld hl, OBJECT_MAP_Y add hl, de ld a, [hl] cp c jr z, .continue jr c, .below inc c jr .continue .below dec c .continue ld hl, OBJECT_MAP_X add hl, de ld [hl], b ld a, b ld hl, wXCoord sub [hl] and $f swap a ld hl, wPlayerBGMapOffsetX sub [hl] ld hl, OBJECT_SPRITE_X add hl, de ld [hl], a ld hl, OBJECT_MAP_Y add hl, de ld [hl], c ld a, c ld hl, wYCoord sub [hl] and $f swap a ld hl, wPlayerBGMapOffsetY sub [hl] ld hl, OBJECT_SPRITE_Y add hl, de ld [hl], a ldh a, [hObjectStructIndex] ld hl, OBJECT_RANGE add hl, de ld [hl], a ld hl, OBJECT_MOVEMENT_TYPE add hl, de ld [hl], SPRITEMOVEDATA_FOLLOWNOTEXACT ld hl, OBJECT_STEP_TYPE add hl, de ld [hl], STEP_TYPE_RESET ret GetRelativeFacing:: ; Determines which way map object e would have to turn to face map object d. Returns carry if it's impossible for whatever reason. ld a, d call GetMapObject ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] cp NUM_OBJECT_STRUCTS jr nc, .carry ld d, a ld a, e call GetMapObject ld hl, MAPOBJECT_OBJECT_STRUCT_ID add hl, bc ld a, [hl] cp NUM_OBJECT_STRUCTS jr nc, .carry ld e, a call .GetFacing_e_relativeto_d ret .carry scf ret .GetFacing_e_relativeto_d: ; Determines which way object e would have to turn to face object d. Returns carry if it's impossible. ; load the coordinates of object d into bc ld a, d call GetObjectStruct ld hl, OBJECT_MAP_X add hl, bc ld a, [hl] ld hl, OBJECT_MAP_Y add hl, bc ld c, [hl] ld b, a push bc ; load the coordinates of object e into de ld a, e call GetObjectStruct ld hl, OBJECT_MAP_X add hl, bc ld d, [hl] ld hl, OBJECT_MAP_Y add hl, bc ld e, [hl] pop bc ; |x1 - x2| ld a, b sub d jr z, .same_x_1 jr nc, .b_right_of_d_1 cpl inc a .b_right_of_d_1 ; |y1 - y2| ld h, a ld a, c sub e jr z, .same_y_1 jr nc, .c_below_e_1 cpl inc a .c_below_e_1 ; |y1 - y2| - |x1 - x2| sub h jr c, .same_y_1 .same_x_1 ; compare the y coordinates ld a, c cp e jr z, .same_x_and_y jr c, .c_directly_below_e ; c directly above e ld d, DOWN and a ret .c_directly_below_e ld d, UP and a ret .same_y_1 ld a, b cp d jr z, .same_x_and_y jr c, .b_directly_right_of_d ; b directly left of d ld d, RIGHT and a ret .b_directly_right_of_d ld d, LEFT and a ret .same_x_and_y scf ret QueueFollowerFirstStep: call .QueueFirstStep jr c, .same ld [wFollowMovementQueue], a xor a ld [wFollowerMovementQueueLength], a ret .same ld a, -1 ld [wFollowerMovementQueueLength], a ret .QueueFirstStep: ld a, [wObjectFollow_Leader] call GetObjectStruct ld hl, OBJECT_MAP_X add hl, bc ld d, [hl] ld hl, OBJECT_MAP_Y add hl, bc ld e, [hl] ld a, [wObjectFollow_Follower] call GetObjectStruct ld hl, OBJECT_MAP_X add hl, bc ld a, d cp [hl] jr z, .check_y jr c, .left and a ld a, movement_step + RIGHT ret .left and a ld a, movement_step + LEFT ret .check_y ld hl, OBJECT_MAP_Y add hl, bc ld a, e cp [hl] jr z, .same_xy jr c, .up and a ld a, movement_step + DOWN ret .up and a ld a, movement_step + UP ret .same_xy scf ret RepositionMockedPlayerObject:: ; map setup command called by map setup script MAPSETUP_CONNECTION after LoadBlockData, ; once the new map blocks have been loaded to wOverworldMapBlocks. ; Only applies during BOARDEVENT_VIEW_MAP_MODE ldh a, [hCurBoardEvent] cp BOARDEVENT_VIEW_MAP_MODE ret nz ; if map at wBeforeViewMapMapGroup, wBeforeViewMapMapNumber is not the current map, ; or a map connected to the current map, we are done. ld hl, wBeforeViewMapMapGroup ld a, [hli] ld b, a ld c, [hl] ; wBeforeViewMapMapNumber ld a, [wMapGroup] cp b jr nz, .next_map_1 ld a, [wMapNumber] cp c jr z, MockPlayerObject .next_map_1 ld a, [wNorthConnectedMapGroup] cp b jr nz, .next_map_2 ld a, [wNorthConnectedMapNumber] cp c ld a, 0 ; north connected map jr z, .is_connected_map .next_map_2 ld a, [wSouthConnectedMapGroup] cp b jr nz, .next_map_3 ld a, [wSouthConnectedMapNumber] cp c ld a, 1 ; south connected map jr z, .is_connected_map .next_map_3 ld a, [wWestConnectedMapGroup] cp b jr nz, .next_map_4 ld a, [wWestConnectedMapNumber] cp c ld a, 2 ; west connected map jr z, .is_connected_map .next_map_4 ld a, [wEastConnectedMapGroup] cp b ret nz ld a, [wEastConnectedMapNumber] cp c ld a, 3 ; east connected map ret nz .is_connected_map ld [wTempByteValue], a ld hl, .got_sprite_coords push hl ld a, [wBeforeViewMapXCoord] ld d, a ld a, [wBeforeViewMapYCoord] ld e, a jumptable_bc .Jumptable, wTempByteValue .Jumptable: dw GetNorthConnectedSpriteCoords dw GetSouthConnectedSpriteCoords dw GetWestConnectedSpriteCoords dw GetEastConnectedSpriteCoords .got_sprite_coords ret nc ; return if sprite is not in visible part of connected map jr MockPlayerObject.loaded_player_mock_coords MockPlayerObject:: ld hl, wBeforeViewMapYCoord ld de, wPlayerMockYCoord ld a, [hli] ld [de], a inc de ld a, [hl] ld [de], a .loaded_player_mock_coords ; refresh wPlayerObjectYCoord and wPlayerObjectXCoord (not strictly necessary) farcall RefreshPlayerCoords ; copy default sprite object to the last object struct ld hl, .DefaultPlayerObject ld de, wMapObject{d:LAST_OBJECT} ld bc, OBJECT_EVENT_SIZE + 1 call CopyBytes ; adjust palette number ld a, [wPlayerCharacter] ld e, PLAYERDATA_OW_PAL call GetPlayerField add PAL_NPC ; convert from PAL_OW to PAL_NPC swap a or OBJECTTYPE_SCRIPT ld [wMapObject{d:LAST_OBJECT}Palette], a ; also wMapObject{d:LAST_OBJECT}Type ; adjust sprite id farcall DeterminePlayerSprite ld a, c ld [wMapObject{d:LAST_OBJECT}Sprite], a ; copy player's coordinates ld hl, wPlayerMockYCoord ld de, wMapObject{d:LAST_OBJECT}YCoord ld a, [hli] add 4 ld [de], a inc de ld a, [hl] ; wPlayerMockXCoord add 4 ld [de], a ; wMapObject{d:LAST_OBJECT}XCoord ; set facing direction ld a, [wBeforeViewMapDirection] srl a srl a maskbits NUM_DIRECTIONS ld b, SPRITEMOVEDATA_STANDING_DOWN add b ld [wMapObject{d:LAST_OBJECT}Movement], a ; display mocked player object ; it will go to the last wMapObjects slot and to whichever wObjectStructs slot ; wObjectStructs[n][MAPOBJECT_OBJECT_STRUCT_ID] links both structs ld a, NUM_OBJECTS - 1 call UnmaskCopyMapObjectStruct ret .DefaultPlayerObject: db -1 ; MAPOBJECT_OBJECT_STRUCT_ID object_event 0, 0, SPRITE_CHRIS, SPRITEMOVEDATA_STANDING_DOWN, 0, 0, -1, -1, PAL_NPC_RED, OBJECTTYPE_SCRIPT, 0, ObjectEvent, -1 GetSouthConnectedSpriteCoords: ; ycoord / 2 <= 2 ld a, e srl a cp 3 ret nc ; [wSouthConnectionStripLocation] ld hl, wSouthConnectionStripLocation ld a, [hli] ld h, [hl] ld l, a ; + (xcoord / 2) srl d ld b, 0 ld c, d add hl, bc ; + ([wMapWidth] + 6) * ycoord / 2 ld a, [wMapWidth] add 6 ld c, a ld b, 0 srl e ld a, e and a jr z, .done .loop add hl, bc dec a jr nz, .loop .done call ConvertConnectedOverworldMapBlockAddressToXYCoords ret GetNorthConnectedSpriteCoords: ; wNorthConnectedMapHeight >= 3 ; ycoord / 2 >= ([wNorthConnectedMapHeight] - 3) ld a, [wNorthConnectedMapHeight] sub 3 jr c, .nope ld c, a ld a, e srl a sub c jr c, .nope ld e, a ; e = ycoord / 2 - ([wNorthConnectedMapHeight] - 3) ; [wNorthConnectionStripLocation] ld hl, wNorthConnectionStripLocation ld a, [hli] ld h, [hl] ld l, a ; + (xcoord / 2) srl d ld b, 0 ld c, d add hl, bc ; + ([wMapWidth] + 6) * {ycoord / 2 - ([wNorthConnectedMapHeight] - 3)} --> + ([wMapWidth] + 6) * e ld a, [wMapWidth] add 6 ld c, a ld b, 0 ld a, e and a jr z, .done .loop add hl, bc dec a jr nz, .loop .done call ConvertConnectedOverworldMapBlockAddressToXYCoords ret .nope xor a ret ; nc GetEastConnectedSpriteCoords: ; xcoord / 2 <= 2 ld a, d srl a cp 3 ret nc ; [wEastConnectionStripLocation] ld hl, wEastConnectionStripLocation ld a, [hli] ld h, [hl] ld l, a ; + (xcoord / 2) srl d ld b, 0 ld c, d add hl, bc ; + ([wMapWidth] + 6) * ycoord / 2 ld a, [wMapWidth] add 6 ld c, a ld b, 0 srl e ld a, e and a jr z, .done .loop add hl, bc dec a jr nz, .loop .done call ConvertConnectedOverworldMapBlockAddressToXYCoords ret GetWestConnectedSpriteCoords: ; wWestConnectedMapWidth >= 3 ; xcoord / 2 >= ([wWestConnectedMapWidth] - 3) ld a, [wWestConnectedMapWidth] sub 3 jr c, .nope ld c, a ld a, d srl a sub c jr c, .nope ld d, a ; d = xcoord / 2 - ([wWestConnectedMapWidth] - 3) ; [wWestConnectionStripLocation] ld hl, wWestConnectionStripLocation ld a, [hli] ld h, [hl] ld l, a ; + xcoord / 2 - ([wWestConnectedMapWidth] - 3) --> + d ld c, d ld b, 0 add hl, bc ; + ([wMapWidth] + 6) * ycoord / 2 ld a, [wMapWidth] add 6 ld c, a ld b, 0 srl e ld a, e and a jr z, .done .loop add hl, bc dec a jr nz, .loop .done call ConvertConnectedOverworldMapBlockAddressToXYCoords ret .nope xor a ret ; nc ; load into wPlayerMockYCoord and wPlayerMockXCoord the coordinates ; that correspond to wOverworldMapBlocks address at hl. ConvertConnectedOverworldMapBlockAddressToXYCoords: ld bc, -wOverworldMapBlocks + $10000 add hl, bc ld a, [wMapWidth] add 6 xor $ff inc a ld c, a ld b, $ff ld d, -2 ; .calc_y_coord_loop inc d ; inc d ; each block in wOverworldMapBlocks occupies two half-blocks add hl, bc ld a, h cp $ff jr nz, .calc_y_coord_loop ; for X, we want the value of l in the second-to-last iteration of the previous loop, ; so undo the last iteration in l by adding [wMapWidth]+6 to it ld a, [wMapWidth] add 6 add l add a ; each block in wOverworldMapBlocks occupies two half-blocks ; substract 6 tiles from y, substract 6 tiles from x. ; the '6's correspond to the 3 extra blocks in each margin of wOverworldMapBlocks. sub 6 ld [wPlayerMockXCoord], a ld a, d sub 6 ld [wPlayerMockYCoord], a call CheckPlayerMockSpriteOutOfScreen ret ; c or nc ; return nc if either X or Y coord is too negative to be visible in the screen. ; this corresponds to half-block coords -5 and -6, which are visible by wOverworldMapBlocks, ; but not by the map sprite engine when it adds 4 to X and to Y to obtain wPlayerObject coords. CheckPlayerMockSpriteOutOfScreen: ld a, [wPlayerMockXCoord] ld b, a ld a, [wPlayerMockYCoord] ld c, a ld a, -5 cp b ret z ; nc cp c ret z ; nc dec a ; -6 cp b ret z ; nc cp c ret z ; nc scf ret