From 11db1300b2a48b3861636f8a092c901e01d110ce Mon Sep 17 00:00:00 2001
From: xCrystal <rgr.crystal@gmail.com>
Date: Mon, 28 Aug 2023 12:03:32 +0200
Subject: [PATCH] Window HUD: Handle Window being fully shown during reanchor
 map (#15)

---
 engine/battle/battle_transition.asm |  3 +--
 engine/overworld/init_map.asm       |  7 +++++--
 home/window.asm                     | 23 +++++++++++++++++------
 3 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/engine/battle/battle_transition.asm b/engine/battle/battle_transition.asm
index 703a4dacc..c626b033f 100644
--- a/engine/battle/battle_transition.asm
+++ b/engine/battle/battle_transition.asm
@@ -70,8 +70,7 @@ DoBattleTransition:
 	call DelayFrame
 	call .LoadPokeballTiles
 	call CopyTilemapAtOnce
-	ld a, SCREEN_HEIGHT_PX
-	ldh [hWY], a
+	call HideWindow_EnableLCDInt
 	call DelayFrame
 	xor a
 	ldh [hBGMapMode], a
diff --git a/engine/overworld/init_map.asm b/engine/overworld/init_map.asm
index 2a8ea4667..c394f3799 100644
--- a/engine/overworld/init_map.asm
+++ b/engine/overworld/init_map.asm
@@ -34,7 +34,11 @@ ReanchorBGMap_NoOAMUpdate::
 	farcall ApplyPals
 	ld a, TRUE
 	ldh [hCGBPalUpdate], a
+	; display window while BG map is reanchored.
+	; disable LCD interrupt to prevent cropping the window due to hWindowHUD
+	; (caller must re-enable when window is hidden again).
 	xor a
+	ldh [rSTAT], a
 	ldh [hBGMapMode], a
 	ldh [hWY], a
 	farcall HDMATransfer_FillBGMap0WithBlack ; no need to farcall
@@ -63,8 +67,7 @@ LoadFont_NoOAMUpdate::
 	ldh [hOAMUpdate], a
 
 	call LoadFrame
-	ld a, $90
-	ldh [hWY], a
+	call HideWindow_EnableLCDInt
 	call SafeUpdateSprites
 	call LoadStandardFont
 
diff --git a/home/window.asm b/home/window.asm
index b2611c384..002ce6dc1 100644
--- a/home/window.asm
+++ b/home/window.asm
@@ -7,8 +7,7 @@ RefreshScreen::
 
 	call ReanchorBGMap_NoOAMUpdate
 	call _OpenAndCloseMenu_HDMATransferTilemapAndAttrmap
-	ld a, $90
-	ldh [hWY], a
+	call HideWindow_EnableLCDInt
 
 	pop af
 	rst Bankswitch
@@ -51,8 +50,7 @@ OpenText2bpp::
 	call ReanchorBGMap_NoOAMUpdate ; clear bgmap
 	call SpeechTextbox2bpp
 	call _OpenAndCloseMenu_HDMATransferTilemapAndAttrmap ; anchor bgmap
-	ld a, $90
-	ldh [hWY], a
+	call HideWindow_EnableLCDInt
 
 	pop af
 	rst Bankswitch
@@ -109,6 +107,18 @@ SafeUpdateSprites::
 	ldh [hOAMUpdate], a
 	ret
 
+HideWindow_EnableLCDInt::
+	ld a, $90
+	ldh [hWY], a
+	ldh a, [hWindowHUD]
+	and a
+	ld a, 1 << rSTAT_INT_HBLANK
+	jr z, .ok
+	ld a, 1 << rSTAT_INT_LYC
+.ok
+	ldh [rSTAT], a
+	ret
+
 OVERWORLD_HUD_HEIGHT EQU 8
 
 EnableOverworldWindowHUD::
@@ -119,11 +129,12 @@ EnableWindowHUD:
 	ldh [hWindowHUD], a
 	; configure LCD interrupt
 	ldh [rLYC], a
-	ld a, 1 << rSTAT_INT_LYC ; LYC=LC
-	ldh [rSTAT], a
 	; make window hidden this frame to prevent graphical glitches
 	ld a, $90
 	ldh [hWY], a
+	; configure LCD interrupt
+	ld a, 1 << rSTAT_INT_LYC ; LYC=LC
+	ldh [rSTAT], a
 	ret
 
 DisableWindowHUD::