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.

1 files changed, 313 insertions, 0 deletions

diff --git a/engine/overworld/map_object_action.asm b/engine/overworld/map_object_action.asm
new file mode 100755
index 000000000..c82cd80a2
--- /dev/null
+++ b/engine/overworld/map_object_action.asm
@@ -0,0 +1,313 @@
+ObjectActionPairPointers: ; 445f
+; entries correspond to OBJECT_ACTION_* constants
+	dw SetFacingStanding,              SetFacingStanding
+	dw SetFacingStandAction,           SetFacingCurrent
+	dw SetFacingStepAction,            SetFacingCurrent
+	dw SetFacingBumpAction,            SetFacingCurrent
+	dw SetFacingCounterclockwiseSpin,  SetFacingCurrent
+	dw SetFacingCounterclockwiseSpin2, SetFacingStanding
+	dw SetFacingFish,                  SetFacingFish
+	dw SetFacingShadow,                SetFacingStanding
+	dw SetFacingEmote,                 SetFacingEmote
+	dw SetFacingBigDollSym,            SetFacingBigDollSym
+	dw SetFacingBounce,                SetFacingFreezeBounce
+	dw SetFacingWeirdTree,             SetFacingCurrent
+	dw SetFacingBigDollAsym,           SetFacingBigDollAsym
+	dw SetFacingBigDoll,               SetFacingBigDoll
+	dw SetFacingBoulderDust,           SetFacingStanding
+	dw SetFacingGrassShake,            SetFacingStanding
+	dw SetFacingSkyfall,               SetFacingCurrent
+; 44a3
+
+SetFacingStanding: ; 44a3
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], STANDING
+	ret
+; 44aa
+
+SetFacingCurrent: ; 44aa
+	call GetSpriteDirection
+	or FACING_STEP_DOWN_0 ; useless
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 44b5
+
+SetFacingStandAction: ; 44b5
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld a, [hl]
+	and 1
+	jr nz, SetFacingStepAction
+	jp SetFacingCurrent
+; 44c1
+
+SetFacingStepAction: ; 44c1
+	ld hl, OBJECT_FLAGS1
+	add hl, bc
+	bit SLIDING, [hl]
+	jp nz, SetFacingCurrent
+
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	ld a, [hl]
+	inc a
+	and %00001111
+	ld [hl], a
+
+	rrca
+	rrca
+	and %00000011
+	ld d, a
+
+	call GetSpriteDirection
+	or FACING_STEP_DOWN_0 ; useless
+	or d
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 44e4
+
+SetFacingSkyfall: ; 44e4
+	ld hl, OBJECT_FLAGS1
+	add hl, bc
+	bit SLIDING, [hl]
+	jp nz, SetFacingCurrent
+
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	ld a, [hl]
+	add 2
+	and %00001111
+	ld [hl], a
+
+	rrca
+	rrca
+	and %00000011
+	ld d, a
+
+	call GetSpriteDirection
+	or FACING_STEP_DOWN_0 ; useless
+	or d
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 4508
+
+SetFacingBumpAction: ; 4508
+	ld hl, OBJECT_FLAGS1
+	add hl, bc
+	bit SLIDING, [hl]
+	jp nz, SetFacingCurrent
+
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	inc [hl]
+
+	ld a, [hl]
+	rrca
+	rrca
+	rrca
+	and %00000011
+	ld d, a
+
+	call GetSpriteDirection
+	or FACING_STEP_DOWN_0 ; useless
+	or d
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 4529
+
+SetFacingCounterclockwiseSpin: ; 4529
+	call CounterclockwiseSpinAction
+	ld hl, OBJECT_FACING
+	add hl, bc
+	ld a, [hl]
+	or FACING_STEP_DOWN_0 ; useless
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 4539
+
+SetFacingCounterclockwiseSpin2: ; 4539
+	call CounterclockwiseSpinAction
+	jp SetFacingStanding
+; 453f
+
+CounterclockwiseSpinAction: ; 453f
+; Here, OBJECT_STEP_FRAME consists of two 2-bit components,
+; using only bits 0,1 and 4,5.
+; bits 0,1 is a timer (4 overworld frames)
+; bits 4,5 determines the facing - the direction is counterclockwise.
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	ld a, [hl]
+	and %11110000
+	ld e, a
+
+	ld a, [hl]
+	inc a
+	and %00001111
+	ld d, a
+	cp 4
+	jr c, .ok
+
+	ld d, 0
+	ld a, e
+	add $10
+	and %00110000
+	ld e, a
+
+.ok
+	ld a, d
+	or e
+	ld [hl], a
+
+	swap e
+	ld d, 0
+	ld hl, .Directions
+	add hl, de
+	ld a, [hl]
+	ld hl, OBJECT_FACING
+	add hl, bc
+	ld [hl], a
+	ret
+; 456a
+
+.Directions: ; 456a
+	db OW_DOWN, OW_RIGHT, OW_UP, OW_LEFT
+; 456e
+
+SetFacingFish: ; 456e
+	call GetSpriteDirection
+	rrca
+	rrca
+	add FACING_FISH_DOWN
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 457b
+
+SetFacingShadow: ; 457b
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], FACING_SHADOW
+	ret
+; 4582
+
+SetFacingEmote: ; 4582 emote
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], FACING_EMOTE
+	ret
+; 4589
+
+SetFacingBigDollSym: ; 4589
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], FACING_BIG_DOLL_SYM
+	ret
+; 4590
+
+SetFacingBounce: ; 4590
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	ld a, [hl]
+	inc a
+	and %00001111
+	ld [hl], a
+	and %00001000
+	jr z, SetFacingFreezeBounce
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], FACING_STEP_UP_0
+	ret
+; 45a4
+
+SetFacingFreezeBounce: ; 45a4
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], FACING_STEP_DOWN_0
+	ret
+; 45ab
+
+SetFacingWeirdTree: ; 45ab
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	ld a, [hl]
+	inc a
+	ld [hl], a
+	and %00001100
+	rrca
+	rrca
+	add FACING_WEIRD_TREE_0
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], a
+	ret
+; 45be
+
+SetFacingBigDollAsym: ; 45be
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], FACING_BIG_DOLL_ASYM
+	ret
+; 45c5
+
+SetFacingBigDoll: ; 45c5
+	ld a, [wVariableSprites + SPRITE_BIG_DOLL - SPRITE_VARS]
+	ld d, FACING_BIG_DOLL_SYM ; symmetric
+	cp SPRITE_BIG_SNORLAX
+	jr z, .ok
+	cp SPRITE_BIG_LAPRAS
+	jr z, .ok
+	ld d, FACING_BIG_DOLL_ASYM ; asymmetric
+
+.ok
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	ld [hl], d
+	ret
+; 45da
+
+SetFacingBoulderDust: ; 45da
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	inc [hl]
+	ld a, [hl]
+
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	and 2
+	ld a, FACING_BOULDER_DUST_1
+	jr z, .ok
+	inc a ; FACING_BOULDER_DUST_2
+.ok
+	ld [hl], a
+	ret
+; 45ed
+
+SetFacingGrassShake: ; 45ed
+	ld hl, OBJECT_STEP_FRAME
+	add hl, bc
+	inc [hl]
+	ld a, [hl]
+	ld hl, OBJECT_FACING_STEP
+	add hl, bc
+	and 4
+	ld a, FACING_GRASS_1
+	jr z, .ok
+	inc a ; FACING_GRASS_2
+
+.ok
+	ld [hl], a
+	ret
+; 4600