From 4ed93e39672a7e215698bf963203bc5373fcf774 Mon Sep 17 00:00:00 2001
From: Lukas Krickl <lukas@krickl.dev>
Date: Tue, 12 Aug 2025 21:16:23 +0200
Subject: [PATCH] objanim: Added top door animation

---
 src/objanim.s      | 60 +++++++++++++++++++++++++++++++++++++++++++++-
 src/roompatterns.s |  6 ++---
 2 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/src/objanim.s b/src/objanim.s
index bce08f6..4090b76 100644
--- a/src/objanim.s
+++ b/src/objanim.s
@@ -20,10 +20,27 @@ objanim_init:
 objanim_door_open:
 	push de
 	push bc
+
+	; set up the correct state based on tile index
+	ld a, b ; a = tile index
+	cp a, DOOR_TILE_TOP
+	jr nz, @not_top REL
+		
+		ld de, st_objanim_door_open_up
+		ld hl, objanim
+		ld bc, st_size
+		call memcpy
+		jp @done
+@not_top:
+
+	; default to down
 	ld de, st_objanim_door_open_down
 	ld hl, objanim
 	ld bc, st_size
 	call memcpy
+
+@done:
+
 	pop bc
 	pop de
 
@@ -52,7 +69,7 @@ objanim_door_open:
 	; clear frame counter
 	xor a, a
 	ld [de], a
-
+	
 	; set gameplay flag to pause object updates
 	ld a, [gameplay_flags]
 	or a, GPF_PAUSE_UPDATE
@@ -93,6 +110,44 @@ objanim_door_open_down_fn:
 	pop bc ; restore next state
 	ret
 
+objanim_door_open_up_fn:
+	ld a, [objanim+obja_timer] ; read timer before calling handler
+	push af
+	call objanim_door_open_generic_fn
+
+	pop af
+	push bc ; save next state
+	; hl = oam ptr
+	inc hl ; skip obj1 y
+
+	; adjust x position based on timer
+	; offset position by counter 
+	sra a
+	ld b, a
+	ld a, [hl]
+	sub a, b
+	; wirte adjusted obj1 x 
+	ld [hl+], a ; hl = obj1 tile
+
+	inc hl ; skip obj1 tile
+	ld a, OAM_FYFLIP
+	ld [hl+], a ; write obj1 flag and ++
+	inc hl ; skip obj2 y 
+	
+	; hl = obj2 x 
+	ld a, [hl]
+	add a, b
+	; write adjusted obj2 x
+	ld [hl+], a
+
+	inc hl ; skip obj2 tile
+	ld a, OAM_FYFLIP ; write obj2 flag 
+	ld [hl], a
+	
+	pop bc ; restore next state
+
+	ret
+
 	; state function for door opening animation
 	; is called by more specific functions that take this base setup
 	; and set the right tiles and animations after
@@ -184,3 +239,6 @@ door_open_done:
 
 st_objanim_door_open_down:
 	st_def 0x00, objanim_door_open_down_fn, st_objanim_door_open_down 
+
+st_objanim_door_open_up:
+	st_def 0x00, objanim_door_open_up_fn, st_objanim_door_open_up 
diff --git a/src/roompatterns.s b/src/roompatterns.s
index 4eb6e7a..a78b1b6 100644
--- a/src/roompatterns.s
+++ b/src/roompatterns.s
@@ -99,8 +99,8 @@ room_pattern_special1:
   .db RPLW, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRF, RPRW
   .db RPBL, RPBW, RPBW, RPBW, RPBW, RPDB, RPBW, RPBW, RPBW, RPBW, RPBW, RPBW, RPBW, RPBR
 
-#define DOOR_TILE_TOP 0x0E
-#define DOOR_TILE_BOTTOM 0x2E
+#define DOOR_TILE_TOP 0x2E
+#define DOOR_TILE_BOTTOM 0x0E
 #define DOOR_TILE_LEFT 0x2C
 #define DOOR_TILE_RIGHT 0x0C
   
@@ -113,7 +113,7 @@ room_pattern_tile_translation:
  .db 0x44, 0x42
  .db 0x00 ; floor
  ; doors
- .db DOOR_TILE_BOTTOM, DOOR_TILE_TOP, DOOR_TILE_RIGHT, DOOR_TILE_LEFT 
+ .db DOOR_TILE_TOP, DOOR_TILE_BOTTOM, DOOR_TILE_RIGHT, DOOR_TILE_LEFT 
  ; roof
  .db 0x48
 
-- 
2.30.2