ref: 145d8dd5c22e8e4c5b0dbf2b9b013db37b7dd844
dir: /engine/overworld/player_step.asm/
_HandlePlayerStep:: ld a, [wPlayerStepFlags] and a ret z bit PLAYERSTEP_START_F, a jr nz, .update_overworld_map bit PLAYERSTEP_STOP_F, a jr nz, .update_player_coords bit PLAYERSTEP_CONTINUE_F, a jr nz, .finish ret .update_overworld_map ld a, 4 ld [wHandlePlayerStep], a call UpdateOverworldMap jr .finish .update_player_coords call UpdatePlayerCoords jr .finish .finish call HandlePlayerStep ld a, [wPlayerStepVectorX] ld d, a ld a, [wPlayerStepVectorY] ld e, a ld a, [wPlayerBGMapOffsetX] sub d ld [wPlayerBGMapOffsetX], a ld a, [wPlayerBGMapOffsetY] sub e ld [wPlayerBGMapOffsetY], a ret ScrollScreen:: ld a, [wPlayerStepVectorX] ld d, a ld a, [wPlayerStepVectorY] ld e, a ldh a, [hSCX] add d ldh [hSCX], a ldh a, [hSCY] add e ldh [hSCY], a ret HandlePlayerStep: ld hl, wHandlePlayerStep ld a, [hl] and a ret z dec [hl] ld a, [hl] ld hl, .Jumptable rst JumpTable ret .Jumptable: dw GetMovementPermissions dw BufferScreen dw .mobile dw .fail2 ; The rest are never used. Ever. dw .fail1 dw .fail1 dw .fail1 dw .fail1 dw .fail1 dw .fail1 dw .fail1 .fail1 ret .mobile farcall StubbedTrainerRankings_StepCount ret .fail2 ret UpdatePlayerCoords: ld a, [wPlayerStepDirection] and a jr nz, .check_step_down ld hl, wYCoord inc [hl] ret .check_step_down cp UP jr nz, .check_step_left ld hl, wYCoord dec [hl] ret .check_step_left cp LEFT jr nz, .check_step_right ld hl, wXCoord dec [hl] ret .check_step_right cp RIGHT ret nz ld hl, wXCoord inc [hl] ret UpdateOverworldMap: ld a, [wPlayerStepDirection] and a jr z, .step_down cp UP jr z, .step_up cp LEFT jr z, .step_left cp RIGHT jr z, .step_right ret .step_down call .ScrollOverworldMapDown call LoadMapPart call ScrollMapDown ret .step_up call .ScrollOverworldMapUp call LoadMapPart call ScrollMapUp ret .step_left call .ScrollOverworldMapLeft call LoadMapPart call ScrollMapLeft ret .step_right call .ScrollOverworldMapRight call LoadMapPart call ScrollMapRight ret .ScrollOverworldMapDown: ld a, [wBGMapAnchor] add 2 * BG_MAP_WIDTH ld [wBGMapAnchor], a jr nc, .not_overflowed ld a, [wBGMapAnchor + 1] inc a and %11 or HIGH(vBGMap0) ld [wBGMapAnchor + 1], a .not_overflowed ld hl, wMetatileStandingY inc [hl] ld a, [hl] cp 2 ; was 1 jr nz, .done_down ld [hl], 0 call .ScrollMapDataDown .done_down ret .ScrollMapDataDown: ld hl, wOverworldMapAnchor ld a, [wMapWidth] add 3 * 2 ; surrounding tiles add [hl] ld [hli], a ret nc inc [hl] ret .ScrollOverworldMapUp: ld a, [wBGMapAnchor] sub 2 * BG_MAP_WIDTH ld [wBGMapAnchor], a jr nc, .not_underflowed ld a, [wBGMapAnchor + 1] dec a and %11 or HIGH(vBGMap0) ld [wBGMapAnchor + 1], a .not_underflowed ld hl, wMetatileStandingY dec [hl] ld a, [hl] cp -1 ; was 0 jr nz, .done_up ld [hl], $1 call .ScrollMapDataUp .done_up ret .ScrollMapDataUp: ld hl, wOverworldMapAnchor ld a, [wMapWidth] add 3 * 2 ; surrounding tiles ld b, a ld a, [hl] sub b ld [hli], a ret nc dec [hl] ret .ScrollOverworldMapLeft: ld a, [wBGMapAnchor] ld e, a and $e0 ld d, a ld a, e sub $2 and $1f or d ld [wBGMapAnchor], a ld hl, wMetatileStandingX dec [hl] ld a, [hl] cp -1 jr nz, .done_left ld [hl], 1 call .ScrollMapDataLeft .done_left ret .ScrollMapDataLeft: ld hl, wOverworldMapAnchor ld a, [hl] sub 1 ld [hli], a ret nc dec [hl] ret .ScrollOverworldMapRight: ld a, [wBGMapAnchor] ld e, a and $e0 ld d, a ld a, e add $2 and $1f or d ld [wBGMapAnchor], a ld hl, wMetatileStandingX inc [hl] ld a, [hl] cp 2 jr nz, .done_right ld [hl], 0 call .ScrollMapDataRight .done_right ret .ScrollMapDataRight: ld hl, wOverworldMapAnchor ld a, [hl] add 1 ld [hli], a ret nc inc [hl] ret