Identify `wSavedCoordIndex` and its other usages

15 files changed, 57 insertions, 54 deletions

diff --git a/engine/gfx/sprite_oam.asm b/engine/gfx/sprite_oam.asm
index 4a31ab5e..8704814f 100644
--- a/engine/gfx/sprite_oam.asm
+++ b/engine/gfx/sprite_oam.asm
@@ -28,7 +28,7 @@ PrepareOAMData::
 	inc e
 	inc e
 	ld a, [de] ; [x#SPRITESTATEDATA1_IMAGEINDEX]
-	ld [wSpriteImageIndexBackup], a
+	ld [wSavedSpriteImageIndex], a
 	cp $ff ; off-screen (don't draw)
 	jr nz, .visible
 
@@ -98,7 +98,7 @@ PrepareOAMData::
 	push bc
 	ld b, a
 
-	ld a, [wSpriteImageIndexBackup]
+	ld a, [wSavedSpriteImageIndex]
 	swap a                   ; high nybble determines sprite used (0 is always player sprite, next are some npcs)
 	and $f
 
diff --git a/engine/items/item_effects.asm b/engine/items/item_effects.asm
index 927f54cb..12c7dade 100644
--- a/engine/items/item_effects.asm
+++ b/engine/items/item_effects.asm
@@ -740,7 +740,7 @@ ItemUseSurfboard:
 	ld a, b
 	ld [wSimulatedJoypadStatesEnd], a
 	xor a
-	ld [wWastedByteCD39], a
+	ld [wUnusedCD39], a
 	inc a
 	ld [wSimulatedJoypadStatesIndex], a
 	ret
diff --git a/engine/menus/pokedex.asm b/engine/menus/pokedex.asm
index 3411f729..96bae343 100644
--- a/engine/menus/pokedex.asm
+++ b/engine/menus/pokedex.asm
@@ -36,7 +36,7 @@ ShowPokedexMenu:
 	ld [wCurrentMenuItem], a
 	ld [wLastMenuItem], a
 	ldh [hJoy7], a
-	ld [wWastedByteCD3A], a
+	ld [wUnusedCD3A], a
 	ld [wOverrideSimulatedJoypadStatesMask], a
 	pop af
 	ld [wListScrollOffset], a
diff --git a/engine/overworld/auto_movement.asm b/engine/overworld/auto_movement.asm
index 75816886..53b70c19 100644
--- a/engine/overworld/auto_movement.asm
+++ b/engine/overworld/auto_movement.asm
@@ -17,7 +17,7 @@ PlayerStepOutFromDoor::
 	ret
 .notStandingOnDoor
 	xor a
-	ld [wWastedByteCD3A], a
+	ld [wUnusedCD3A], a
 	ld [wSimulatedJoypadStatesIndex], a
 	ld [wSimulatedJoypadStatesEnd], a
 	ld hl, wd736
@@ -39,7 +39,7 @@ _EndNPCMovementScript::
 	ld [wNPCMovementScriptSpriteOffset], a
 	ld [wNPCMovementScriptPointerTableNum], a
 	ld [wNPCMovementScriptFunctionNum], a
-	ld [wWastedByteCD3A], a
+	ld [wUnusedCD3A], a
 	ld [wSimulatedJoypadStatesIndex], a
 	ld [wSimulatedJoypadStatesEnd], a
 	ret
diff --git a/engine/overworld/movement.asm b/engine/overworld/movement.asm
index e08da61a..eb186f1e 100644
--- a/engine/overworld/movement.asm
+++ b/engine/overworld/movement.asm
@@ -179,7 +179,7 @@ UpdateNPCSprite:
 	res 0, [hl]
 	xor a
 	ld [wSimulatedJoypadStatesIndex], a
-	ld [wWastedByteCD3A], a
+	ld [wUnusedCD3A], a
 	ret
 .next
 	cp WALK
diff --git a/home/overworld.asm b/home/overworld.asm
index 8085f484..885a5327 100644
--- a/home/overworld.asm
+++ b/home/overworld.asm
@@ -1869,7 +1869,7 @@ JoypadOverworld::
 ; if done simulating button presses
 .doneSimulating
 	xor a
-	ld [wWastedByteCD3A], a
+	ld [wUnusedCD3A], a
 	ld [wSimulatedJoypadStatesIndex], a
 	ld [wSimulatedJoypadStatesEnd], a
 	ld [wJoyIgnore], a
diff --git a/home/pathfinding.asm b/home/pathfinding.asm
index 53f98847..77cb5c4b 100644
--- a/home/pathfinding.asm
+++ b/home/pathfinding.asm
@@ -40,7 +40,7 @@ MoveSprite_::
 	ld [wSimulatedJoypadStatesEnd], a
 	dec a
 	ld [wJoyIgnore], a
-	ld [wWastedByteCD3A], a
+	ld [wUnusedCD3A], a
 	ret
 
 ; divides [hDividend2] by [hDivisor2] and stores the quotient in [hQuotient2]
diff --git a/ram/wram.asm b/ram/wram.asm
index 8c246b8a..32749db3 100644
--- a/ram/wram.asm
+++ b/ram/wram.asm
@@ -576,10 +576,10 @@ wFilteredBagItemsCount:: db
 wSimulatedJoypadStatesIndex:: db
 
 ; written to but nothing ever reads it
-wWastedByteCD39:: db
+wUnusedCD39:: db
 
 ; written to but nothing ever reads it
-wWastedByteCD3A:: db
+wUnusedCD3A:: db
 
 ; mask indicating which real button presses can override simulated ones
 ; XXX is it ever not 0?
@@ -979,7 +979,10 @@ wBattleResult:: db
 ; bit 0: if set, DisplayTextID automatically draws a text box
 wAutoTextBoxDrawingControl:: db
 
-wcf0d:: db ; used with some overworld scripts (not exactly sure what it's used for)
+; used in some overworld scripts to vary scripted movement
+wSavedCoordIndex::
+wOakWalkedToPlayer::
+wNextSafariZoneGateScript:: db
 
 ; used in CheckForTilePairCollisions2 to store the tile the player is on
 wTilePlayerStandingOn:: db
@@ -1913,8 +1916,8 @@ wMissableObjectFlagsEnd::
 
 	ds 7
 
-; temp copy of SPRITESTATEDATA1_IMAGEINDEX (used for sprite facing/anim)
-wSpriteImageIndexBackup:: db
+; saved copy of SPRITESTATEDATA1_IMAGEINDEX (used for sprite facing/anim)
+wSavedSpriteImageIndex:: db
 
 ; each entry consists of 2 bytes
 ; * the sprite ID (depending on the current map)
diff --git a/scripts/FightingDojo.asm b/scripts/FightingDojo.asm
index 298c2fcb..d434f681 100644
--- a/scripts/FightingDojo.asm
+++ b/scripts/FightingDojo.asm
@@ -32,15 +32,15 @@ FightingDojoDefaultScript:
 	ret nz
 	xor a
 	ldh [hJoyHeld], a
-	ld [wcf0d], a
+	ld [wSavedCoordIndex], a
 	ld a, [wYCoord]
 	cp 3
 	ret nz
 	ld a, [wXCoord]
 	cp 4
 	ret nz
-	ld a, $1
-	ld [wcf0d], a
+	ld a, 1
+	ld [wSavedCoordIndex], a
 	ld a, PLAYER_DIR_RIGHT
 	ld [wPlayerMovingDirection], a
 	ld a, FIGHTINGDOJO_KARATE_MASTER
@@ -57,8 +57,8 @@ FightingDojoKarateMasterPostBattleScript:
 	ld a, [wIsInBattle]
 	cp $ff
 	jp z, FightingDojoResetScripts
-	ld a, [wcf0d]
-	and a
+	ld a, [wSavedCoordIndex]
+	and a ; nz if the player was at (4, 3), left of the Karate Master
 	jr z, .already_facing
 	ld a, PLAYER_DIR_RIGHT
 	ld [wPlayerMovingDirection], a
diff --git a/scripts/PalletTown.asm b/scripts/PalletTown.asm
index dd898ac6..4d5bebf0 100644
--- a/scripts/PalletTown.asm
+++ b/scripts/PalletTown.asm
@@ -45,7 +45,7 @@ PalletTownDefaultScript:
 
 PalletTownOakHeyWaitScript:
 	xor a
-	ld [wcf0d], a
+	ld [wOakWalkedToPlayer], a
 	ld a, TEXT_PALLETTOWN_OAK
 	ldh [hSpriteIndexOrTextID], a
 	call DisplayTextID
@@ -96,8 +96,8 @@ PalletTownOakNotSafeComeWithMeScript:
 	ret nz
 	xor a ; ld a, SPRITE_FACING_DOWN
 	ld [wSpritePlayerStateData1FacingDirection], a
-	ld a, 1
-	ld [wcf0d], a
+	ld a, TRUE
+	ld [wOakWalkedToPlayer], a
 	ld a, SELECT | START | D_RIGHT | D_LEFT | D_UP | D_DOWN
 	ld [wJoyIgnore], a
 	ld a, TEXT_PALLETTOWN_OAK
@@ -161,7 +161,7 @@ PalletTown_TextPointers:
 
 PalletTownOakText:
 	text_asm
-	ld a, [wcf0d]
+	ld a, [wOakWalkedToPlayer]
 	and a
 	jr nz, .next
 	ld a, 1
diff --git a/scripts/Route22.asm b/scripts/Route22.asm
index abf6c8e4..1e575e43 100644
--- a/scripts/Route22.asm
+++ b/scripts/Route22.asm
@@ -38,7 +38,7 @@ Route22GetRivalTrainerNoByStarterScript:
 
 Route22MoveRivalRightScript:
 	ld de, Route22RivalMovementData
-	ld a, [wcf0d]
+	ld a, [wSavedCoordIndex]
 	cp $1
 	jr z, .skip_first_right
 	inc de
@@ -62,7 +62,7 @@ Route22DefaultScript:
 	call ArePlayerCoordsInArray
 	ret nc
 	ld a, [wCoordIndex]
-	ld [wcf0d], a
+	ld [wSavedCoordIndex], a
 	xor a
 	ldh [hJoyHeld], a
 	ld a, D_RIGHT | D_LEFT | D_UP | D_DOWN
@@ -107,8 +107,8 @@ Route22Rival1StartBattleScript:
 	ld a, [wd730]
 	bit 0, a
 	ret nz
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, lower entry in Route22DefaultScript.Route22RivalBattleCoords
 	jr nz, .set_rival_facing_right
 	ld a, PLAYER_DIR_DOWN
 	ld [wPlayerMovingDirection], a
@@ -172,8 +172,8 @@ Route22Rival1AfterBattleScript:
 	ld [wNewSoundID], a
 	call PlaySound
 	farcall Music_RivalAlternateStart
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, lower entry in Route22DefaultScript.Route22RivalBattleCoords
 	jr nz, .exit_movement_2
 	call .RivalExit1Script
 	jr .next_script
@@ -263,8 +263,8 @@ Route22Rival2StartBattleScript:
 	ret nz
 	ld a, ROUTE22_RIVAL2
 	ldh [hSpriteIndex], a
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, lower entry in Route22DefaultScript.Route22RivalBattleCoords
 	jr nz, .set_player_direction_left
 	ld a, PLAYER_DIR_DOWN
 	ld [wPlayerMovingDirection], a
@@ -307,8 +307,8 @@ Route22Rival2AfterBattleScript:
 	jp z, Route22SetDefaultScript
 	ld a, ROUTE22_RIVAL2
 	ldh [hSpriteIndex], a
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, lower entry in Route22DefaultScript.Route22RivalBattleCoords
 	jr nz, .set_player_direction_left
 	ld a, PLAYER_DIR_DOWN
 	ld [wPlayerMovingDirection], a
@@ -331,8 +331,8 @@ Route22Rival2AfterBattleScript:
 	ld [wNewSoundID], a
 	call PlaySound
 	farcall Music_RivalAlternateStartAndTempo
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, lower entry in Route22DefaultScript.Route22RivalBattleCoords
 	jr nz, .exit_movement_2
 	call .RivalExit1Script
 	jr .next_script
diff --git a/scripts/SafariZoneGate.asm b/scripts/SafariZoneGate.asm
index a0f9c1f4..14a8a79b 100644
--- a/scripts/SafariZoneGate.asm
+++ b/scripts/SafariZoneGate.asm
@@ -29,14 +29,14 @@ SafariZoneGateDefaultScript:
 	ld a, SPRITE_FACING_RIGHT
 	ld [wSpritePlayerStateData1FacingDirection], a
 	ld a, [wCoordIndex]
-	cp $1
+	cp 1 ; index of second, lower entry in .PlayerNextToSafariZoneWorker1CoordsArray
 	jr z, .player_not_next_to_worker
 	ld a, SCRIPT_SAFARIZONEGATE_WOULD_YOU_LIKE_TO_JOIN
 	ld [wSafariZoneGateCurScript], a
 	ret
 .player_not_next_to_worker
 	ld a, D_RIGHT
-	ld c, $1
+	ld c, 1
 	call SafariZoneEntranceAutoWalk
 	ld a, D_RIGHT | D_LEFT | D_UP | D_DOWN
 	ld [wJoyIgnore], a
@@ -88,7 +88,7 @@ SafariZoneGateLeavingSafariScript:
 	xor a
 	ld [wNumSafariBalls], a
 	ld a, D_DOWN
-	ld c, $3
+	ld c, 3
 	call SafariZoneEntranceAutoWalk
 	ld a, SCRIPT_SAFARIZONEGATE_PLAYER_MOVING_DOWN
 	ld [wSafariZoneGateCurScript], a
@@ -113,7 +113,7 @@ SafariZoneGateSetScriptAfterMoveScript:
 	call SafariZoneGateReturnSimulatedJoypadStateScript
 	ret nz
 	call Delay3
-	ld a, [wcf0d]
+	ld a, [wNextSafariZoneGateScript]
 	ld [wSafariZoneGateCurScript], a
 	ret
 
@@ -236,11 +236,11 @@ SafariZoneGateSafariZoneWorker1LeavingEarlyText:
 	xor a
 	ld [wSpritePlayerStateData1FacingDirection], a
 	ld a, D_DOWN
-	ld c, $3
+	ld c, 3
 	call SafariZoneEntranceAutoWalk
 	ResetEvents EVENT_SAFARI_GAME_OVER, EVENT_IN_SAFARI_ZONE
-	ld a, $0
-	ld [wcf0d], a
+	ld a, SCRIPT_SAFARIZONEGATE_DEFAULT
+	ld [wNextSafariZoneGateScript], a
 	jr .set_current_script
 .not_ready_to_leave
 	ld hl, .GoodLuckText
@@ -248,10 +248,10 @@ SafariZoneGateSafariZoneWorker1LeavingEarlyText:
 	ld a, SPRITE_FACING_UP
 	ld [wSpritePlayerStateData1FacingDirection], a
 	ld a, D_UP
-	ld c, $1
+	ld c, 1
 	call SafariZoneEntranceAutoWalk
 	ld a, SCRIPT_SAFARIZONEGATE_LEAVING_SAFARI
-	ld [wcf0d], a
+	ld [wNextSafariZoneGateScript], a
 .set_current_script
 	ld a, SCRIPT_SAFARIZONEGATE_SET_SCRIPT_AFTER_MOVE
 	ld [wSafariZoneGateCurScript], a
diff --git a/scripts/SilphCo11F.asm b/scripts/SilphCo11F.asm
index 1a2978a8..778283c5 100644
--- a/scripts/SilphCo11F.asm
+++ b/scripts/SilphCo11F.asm
@@ -170,7 +170,7 @@ SilphCo11FDefaultScript:
 	call ArePlayerCoordsInArray
 	jp nc, CheckFightingMapTrainers
 	ld a, [wCoordIndex]
-	ld [wcf0d], a
+	ld [wSavedCoordIndex], a
 	xor a
 	ldh [hJoyHeld], a
 	ld a, D_RIGHT | D_LEFT | D_UP | D_DOWN
@@ -209,8 +209,8 @@ SilphCo11FGiovanniAfterBattleScript:
 	ld a, [wIsInBattle]
 	cp $ff
 	jp z, SilphCo11FResetCurScript
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, upper-right entry in SilphCo11FDefaultScript.PlayerCoordsArray
 	jr z, .face_player_up
 	ld a, PLAYER_DIR_LEFT
 	ld b, SPRITE_FACING_RIGHT
@@ -242,8 +242,8 @@ SilphCo11FGiovanniBattleFacingScript:
 	ld a, SILPHCO11F_GIOVANNI
 	ldh [hSpriteIndex], a
 	call SetSpriteMovementBytesToFF
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, upper-right entry in SilphCo11FDefaultScript.PlayerCoordsArray
 	jr z, .face_player_up
 	ld a, PLAYER_DIR_LEFT
 	ld b, SPRITE_FACING_RIGHT
diff --git a/scripts/SilphCo7F.asm b/scripts/SilphCo7F.asm
index c6afd27a..bfa78847 100644
--- a/scripts/SilphCo7F.asm
+++ b/scripts/SilphCo7F.asm
@@ -145,8 +145,8 @@ SilphCo7FDefaultScript:
 	call SetSpriteMovementBytesToFF
 	ld de, .RivalMovementUp
 	ld a, [wCoordIndex]
-	ld [wcf0d], a
-	cp $1
+	ld [wSavedCoordIndex], a
+	cp 1 ; index of second, lower entry in .RivalEncounterCoordinates
 	jr z, .full_rival_movement
 	inc de
 .full_rival_movement
@@ -225,8 +225,8 @@ SilphCo7FRivalAfterBattleScript:
 	call PlaySound
 	farcall Music_RivalAlternateStart
 	ld de, .RivalWalkAroundPlayerMovement
-	ld a, [wcf0d]
-	cp $1
+	ld a, [wSavedCoordIndex]
+	cp 1 ; index of second, lower entry in SilphCo7FDefaultScript.RivalEncounterCoordinates
 	jr nz, .walk_around_player
 	ld de, .RivalExitRightMovement
 .walk_around_player
diff --git a/scripts/VermilionCity.asm b/scripts/VermilionCity.asm
index 4c8a0b18..9d800233 100644
--- a/scripts/VermilionCity.asm
+++ b/scripts/VermilionCity.asm
@@ -47,7 +47,7 @@ VermilionCityDefaultScript:
 	ret nc
 	xor a
 	ldh [hJoyHeld], a
-	ld [wcf0d], a
+	ld [wSavedCoordIndex], a ; unnecessary
 	ld a, TEXT_VERMILIONCITY_SAILOR1
 	ldh [hSpriteIndexOrTextID], a
 	call DisplayTextID