Organize the engine/ directory

This is an informed attempt at reorganizing the engine/ directory by
creating categorized subdirectories, in order to make it easier to
navigate and find things.

The directories created are as follows:
* engine/game: Contains all "minigames", things like the unown puzzle
and slot machine.
* engine/gfx: Contains all handling of graphics. From loading palettes
to playing animations.
* engine/link: Contains all multiplayer functionality.
* engine/menu: Contains all generic/misc. menus and menu code.
Other, more specialized menus are in their own subdirectories (pokedex,
pokegear, party menu, etc).
* engine/overworld: Contains all handling of the overworld. From loading
and connecting maps to wild encounters and the scripting engine.
* engine/pokegear: In the same vein as engine/pokedex, except it could
use some more splitting up.
* engine/pokemon: Contains everything related to manipulating pokemon
data. From the pokemon storage system to evolution and mail.
* engine/printer: Contains everything related to printing things as well
as the printer communication.
* engine/title: Contains intro sequences, title screens and credits.

engine/overworld/map_setup.asm

@@ -0,0 +1,260 @@
+RunMapSetupScript:: ; 15363
+	ld a, [hMapEntryMethod]
+	and $f
+	dec a
+	ld c, a
+	ld b, 0
+	ld hl, MapSetupScripts
+	add hl, bc
+	add hl, bc
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	call ReadMapSetupScript
+	ret
+; 15377
+
+INCLUDE "data/maps/setup_scripts.asm"
+
+ReadMapSetupScript: ; 1541d
+.loop
+	ld a, [hli]
+	cp -1
+	ret z
+
+	push hl
+
+	ld c, a
+	ld b, 0
+	ld hl, MapSetupCommands
+	add hl, bc
+	add hl, bc
+	add hl, bc
+
+	; bank
+	ld b, [hl]
+	inc hl
+
+	; address
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+
+	; Bit 7 of the bank indicates a parameter.
+	; This is left unused.
+	bit 7, b
+	jr z, .go
+
+	pop de
+	ld a, [de]
+	ld c, a
+	inc de
+	push de
+
+.go
+	ld a, b
+	and $7f
+	rst FarCall
+
+	pop hl
+	jr .loop
+; 15440
+
+MapSetupCommands: ; 15440
+; entries correspond to command indexes in constants/map_setup_constants.asm
+	dba EnableLCD ; 00
+	dba DisableLCD ; 01
+	dba MapSetup_Sound_Off ; 02
+	dba PlayMapMusic ; 03
+	dba RestartMapMusic ; 04
+	dba FadeToMapMusic ; 05
+	dba RotatePalettesRightMapAndMusic ; 06
+	dba EnterMapMusic ; 07
+	dba ForceMapMusic ; 08
+	dba FadeInMusic ; 09
+	dba LoadBlockData ; 0a (callback 1)
+	dba LoadNeighboringBlockData ; 0b
+	dba SaveScreen ; 0c
+	dba BufferScreen ; 0d
+	dba LoadGraphics ; 0e
+	dba LoadTileset ; 0f
+	dba LoadMapTimeOfDay ; 10
+	dba LoadMapPalettes ; 11
+	dba LoadWildMonData ; 12
+	dba RefreshMapSprites ; 13
+	dba HandleNewMap ; 14
+	dba InitCommandQueue ; 15
+	dba LoadObjectsRunCallback_02 ; 16
+	dba LoadSpawnPoint ; 17
+	dba EnterMapConnection ; 18
+	dba LoadWarpData ; 19
+	dba LoadMapAttributes ; 1a
+	dba LoadMapAttributes_SkipPeople ; 1b
+	dba ClearBGPalettes ; 1c
+	dba FadeOutPalettes ; 1d
+	dba FadeInPalettes ; 1e
+	dba GetCoordOfUpperLeftCorner ; 1f
+	dba RestoreFacingAfterWarp ; 20
+	dba SpawnInFacingDown ; 21
+	dba SpawnPlayer ; 22
+	dba RefreshPlayerCoords ; 23
+	dba DelayClearingOldSprites ; 24
+	dba DelayLoadingNewSprites ; 25
+	dba UpdateRoamMons ; 26
+	dba JumpRoamMons ; 27
+	dba FadeOldMapMusic ; 28
+	dba ActivateMapAnims ; 29
+	dba SuspendMapAnims ; 2a
+	dba RetainOldPalettes ; 2b
+	dba DontScrollText ; 2c
+	dba ReturnFromMapSetupScript ; 2d
+; 154ca
+
+
+DontScrollText: ; 154ca
+	xor a
+	ld [wDisableTextAcceleration], a
+	ret
+; 154cf
+
+ActivateMapAnims: ; 154cf
+	ld a, $1
+	ld [hMapAnims], a
+	ret
+; 154d3
+
+SuspendMapAnims: ; 154d3
+	xor a
+	ld [hMapAnims], a
+	ret
+; 154d7
+
+LoadObjectsRunCallback_02: ; 154d7
+	ld a, MAPCALLBACK_OBJECTS
+	call RunMapCallback
+	farcall LoadObjectMasks
+	farcall InitializeVisibleSprites
+	ret
+; 154ea (5:54ea)
+
+; unused
+	ret
+; 154eb
+
+DelayClearingOldSprites: ; 154eb
+	ld hl, wPlayerSpriteSetupFlags
+	set PLAYERSPRITESETUP_RESET_ACTION_F, [hl]
+	ret
+; 154f1
+
+DelayLoadingNewSprites: ; 154f1
+	ld hl, wPlayerSpriteSetupFlags
+	set PLAYERSPRITESETUP_SKIP_RELOAD_GFX_F, [hl]
+	ret
+
+CheckReplaceKrisSprite: ; 154f7
+	nop
+	call .CheckBiking
+	jr c, .ok
+	call .CheckSurfing
+	jr c, .ok
+	call .CheckSurfing2
+	jr c, .ok
+	ret
+
+.ok
+	call ReplaceKrisSprite
+	ret
+
+.CheckBiking: ; 1550c (5:550c)
+	and a
+	ld hl, wBikeFlags
+	bit BIKEFLAGS_ALWAYS_ON_BIKE_F, [hl]
+	ret z
+	ld a, PLAYER_BIKE
+	ld [wPlayerState], a
+	scf
+	ret
+
+.CheckSurfing2: ; 1551a (5:551a)
+	ld a, [wPlayerState]
+	cp PLAYER_NORMAL
+	jr z, .nope
+	cp PLAYER_SKATE
+	jr z, .nope
+	cp PLAYER_SURF
+	jr z, .surfing
+	cp PLAYER_SURF_PIKA
+	jr z, .surfing
+	call GetMapEnvironment
+	cp INDOOR
+	jr z, .checkbiking
+	cp ENVIRONMENT_5
+	jr z, .checkbiking
+	cp DUNGEON
+	jr z, .checkbiking
+	jr .nope
+.checkbiking
+	ld a, [wPlayerState]
+	cp PLAYER_BIKE
+	jr nz, .nope
+.surfing
+	ld a, PLAYER_NORMAL
+	ld [wPlayerState], a
+	scf
+	ret
+
+.nope
+	and a
+	ret
+
+.CheckSurfing: ; 1554e (5:554e)
+	call CheckOnWater
+	jr nz, .ret_nc
+	ld a, [wPlayerState]
+	cp PLAYER_SURF
+	jr z, ._surfing
+	cp PLAYER_SURF_PIKA
+	jr z, ._surfing
+	ld a, PLAYER_SURF
+	ld [wPlayerState], a
+._surfing
+	scf
+	ret
+.ret_nc
+	and a
+	ret
+; 15567
+
+FadeOldMapMusic: ; 15567
+	ld a, 6
+	call SkipMusic
+	ret
+; 1556d
+
+RetainOldPalettes: ; 1556d
+	farcall _UpdateTimePals
+	ret
+
+RotatePalettesRightMapAndMusic: ; 15574
+	ld e, 0
+	ld a, [wMusicFadeID]
+	ld d, 0
+	ld a, [wMusicFadeID + 1]
+	ld a, $4
+	ld [wMusicFade], a
+	call RotateThreePalettesRight
+	ret
+; 15587
+
+ForceMapMusic: ; 15587
+	ld a, [wPlayerState]
+	cp PLAYER_BIKE
+	jr nz, .notbiking
+	call VolumeOff
+	ld a, $88
+	ld [wMusicFade], a
+.notbiking
+	call TryRestartMapMusic
+	ret
+; 1559a