First Commit

Upload literally everything from the pokecrystal16 expand-move-ID branch

engine/overworld/player_step.asm

@@ -0,0 +1,270 @@
+_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, wPlayerMetatileY
+	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, wPlayerMetatileY
+	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, wPlayerMetatileX
+	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, wPlayerMetatileX
+	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