From 35f03a3d754d988aa33be953412dc81d2a7fe7b5 Mon Sep 17 00:00:00 2001
From: Lukas Krickl <lukas@krickl.dev>
Date: Thu, 30 Oct 2025 17:57:20 +0100
Subject: [PATCH] map: wip player scrolling

---
 src/map.s    |  5 -----
 src/player.s | 33 +++++++++++++++++++++++++++++----
 src/tiles.s  |  2 +-
 src/video.s  | 12 ++++++++++++
 src/wram.s   |  3 +++
 5 files changed, 45 insertions(+), 10 deletions(-)

diff --git a/src/map.s b/src/map.s
index e8afa88..f04823e 100644
--- a/src/map.s
+++ b/src/map.s
@@ -33,11 +33,6 @@ map_load:
 	call player_init
 	call ui_init
 
-	; initial scroll value 
-	; to make bottom of scrn0 visible
-	ld a, 144
-	ld [scroll_y], a
-
 	ret
 	
 	; loads a tileset
diff --git a/src/player.s b/src/player.s
index 8fb8662..9a98f0e 100644
--- a/src/player.s
+++ b/src/player.s
@@ -4,10 +4,15 @@
 
 	; sets up the player actor
 player_init:
+	xor a, a
+	ld [player+act_pos_y], a
+	ld [player+act_pos_x], a
+	
 	ret
 	
 	; updates the special player actor
-player_update:
+player_update:	
+	call scroll_center_player
 	ret
 	
 	; draws player at current location
@@ -16,10 +21,29 @@ player_draw:
 	call oamalloc
 	
 	; write left cursor
-	ld a, 100
+
+	; calculate y pos
+	ld a, [scroll_y]
+	ld b, a ; b = scroll y
+
+	ld a, [player+act_pos_y]
+	add a, OBJ_OFF_Y
+	sub a, b
+	; store y for second obj
+	ld [tmp_y], a
 
 	; write y
 	ld [hl+], a
+	
+	; calculate x pos
+	ld a, [scroll_x]
+	ld b, a
+	sub a, b
+
+	ld a, [player+act_pos_x]
+	add a, OBJ_OFF_X
+	; store x for second obj
+	ld [tmp_x], a
 
 	; write x
 	ld [hl+], a
@@ -36,11 +60,12 @@ player_draw:
 
 
 	; write y
-	ld a, 100
+	ld a, [tmp_y]
 	ld [hl+], a
 
 	; write x
-	ld a, 108
+	ld a, [tmp_x]
+	add a, 8
 	ld [hl+], a
 
 	; write tile
diff --git a/src/tiles.s b/src/tiles.s
index 4f1c9da..6327de7 100644
--- a/src/tiles.s
+++ b/src/tiles.s
@@ -1,7 +1,7 @@
 	; tile definitions
 
 #define GFX_GRASS 0x48
-#define GFX_PHIVE 0x4A
+#define GFX_PHIVE 0x62
 #define GFX_EHIVE 0x4A
 #define GFX_FOOD 0x03
 	
diff --git a/src/video.s b/src/video.s
index 1900c0d..f421c6c 100644
--- a/src/video.s
+++ b/src/video.s
@@ -156,6 +156,18 @@ video_wait_n_frames:
     or a, c
   jr nz, video_wait_n_frames REL
   ret
+	
+	; centers scroll on player
+	; but does not allow camera to wrap
+scroll_center_player:
+	ld a, [player+act_pos_y]
+	sub a, 32
+	ld [scroll_y], a
+
+	ld a, [player+act_pos_x]
+	sub a, 32
+	ld [scroll_x], a
+	ret
 
 
   ; loads tilesets
diff --git a/src/wram.s b/src/wram.s
index 1e7bc88..d099a18 100644
--- a/src/wram.s
+++ b/src/wram.s
@@ -68,6 +68,9 @@ srand: .adv 2
 
 player: .adv act_size
 enemy: .adv act_size
+
+tmp_y: .adv 1
+tmp_x: .adv 1
 	
 	; current map ptr
 map: .adv 2
-- 
2.30.2