From 304dbbf96191f5eec39146006ac69acfea9f524e Mon Sep 17 00:00:00 2001
From: Lukas Krickl <lukas@krickl.dev>
Date: Sat, 20 Sep 2025 17:01:19 +0200
Subject: [PATCH] actor: adjusting actors with scroll

Fixed map row draw not wrapping when reaching end of scrn0
---
 src/actor.s  |  5 +----
 src/defs.s   |  1 +
 src/map.s    | 11 +++++++++++
 src/mapobj.s |  4 ++++
 src/player.s |  6 +++---
 src/video.s  | 35 +++++++++++++++++++++++++++++++++--
 6 files changed, 53 insertions(+), 9 deletions(-)

diff --git a/src/actor.s b/src/actor.s
index aa5396e..29632a3 100644
--- a/src/actor.s
+++ b/src/actor.s
@@ -31,9 +31,6 @@ actor_draw:
 	add a, OBJ_OFF_Y
 	inc de ; de = y_hi 
 	add a, b ; a = y postion
-	ld b, a
-	ld a, [scroll_y]
-	add a, b
 
 	ld b, a
 	ld a, [de] ; a = y_hi
@@ -120,7 +117,7 @@ actor_load_test:
 	call memcpy
 
 	; set a test position
-	ld a, 130
+	ld a, 30
 	ld [actors+act_pos_y], a
 	ld [actors+act_pos_x], a
 
diff --git a/src/defs.s b/src/defs.s
index 319a96b..dab08a2 100644
--- a/src/defs.s
+++ b/src/defs.s
@@ -93,6 +93,7 @@
 
 	; map object types
 .se 0
+.de MOT_NOP, 1
 .de MOT_SET_PAT, 1
 .de MOT_DISABLE_SCROLL, 1
 .de MOT_ENABLE_SCROLL, 1
diff --git a/src/map.s b/src/map.s
index 5c59384..09b1c5c 100644
--- a/src/map.s
+++ b/src/map.s
@@ -180,6 +180,16 @@ map_advance_row:
 	ld a, h
 	ld [map_scrn_ptr+1], a
 	
+	; check if we reached the last row of scrn0
+	cp a, 0x97 
+	jr nz, @not_end_of_scrn0 REL
+		; end of scrn0 - wrap around back to first row
+		ld a, SCRN0_END LO
+		ld [map_scrn_ptr], a
+		ld a, SCRN0_END HI
+		ld [map_scrn_ptr+1], a
+@not_end_of_scrn0:
+	
 	; move to next row
 	ld a, [map_curr_row]
 	inc a
@@ -227,3 +237,4 @@ l1_map:
 l1_objs:
 	modef MOT_SET_PAT, 0, 3, pat_center_grass 
 	modef MOT_SET_PAT, 0, 5, pat_empty
+	modef MOT_NOP, 0, 0xFF, 0
diff --git a/src/mapobj.s b/src/mapobj.s
index fbd0c33..2ceab5d 100644
--- a/src/mapobj.s
+++ b/src/mapobj.s
@@ -6,12 +6,16 @@
 ; when an object is off-screen it is unloded
 
 mo_routines:
+	 dw mo_nop
 	 dw mo_set_pat
 	 dw mo_disable_scroll
 	 dw mo_enable_scroll
 	 dw mo_rect
 	 dw mo_actor_spawner
 	
+mo_nop:
+	ret
+
 	; executes all map objects in the map object list 
 	; until the mo's row != current row
 	; advances mo ptr
diff --git a/src/player.s b/src/player.s
index e0eb4f5..5949dcd 100644
--- a/src/player.s
+++ b/src/player.s
@@ -3,15 +3,15 @@
 	; sets up the player actor
 player_init:
 	; initial position
-	ld a, 132
+	ld a, 0
 	ld [player+act_pos_y], a
-	ld a, 24
+	ld a, 0
 	ld [player+act_pos_x], a
 
 	ld a, 0 
 	ld [player+act_pos_y_hi], a
 
-	ld a, 0xA0 ; initial next scroll
+	ld a, 0x30 ; initial next scroll
 	ld [player_next_scroll_y], a
 	ret
 	
diff --git a/src/video.s b/src/video.s
index 7a22390..8b4dc62 100644
--- a/src/video.s
+++ b/src/video.s
@@ -10,11 +10,12 @@ vblank:
   ld a, [RLCD]
   or a, LCDCF_OBJON
   ld [RLCD], a
+	
+	call video_map_perform_scroll
   
   ; dma previous frame's oam
   call OAMDMAFN
 
-	call video_map_perform_scroll
 
   call scroll_write
   
@@ -37,17 +38,47 @@ video_map_perform_scroll:
 	ld [scroll_y], a
 
 	ld a, [player_next_scroll_y]
-	sub a, MAP_ROW_H
+	; sub a, MAP_ROW_H/2
 	ld [player_next_scroll_y], a
 	
 	call map_advance_row
 
+	call scroll_up_adjust
+
 	; unset flag
 	ld a, [game_flags]
 	and a, ~GPF_SCROLL & 0xFF
 	ld [game_flags], a
 	ret
+	
+	; adjusts all actors and rectangles positions
+	; when a scroll occurs
+scroll_up_adjust:
+	ld b, ACTS_MAX
+	ld hl, actors
+
+@act_loop:
+	push hl
+
+	ld de, act_pos_y
+	add hl, de
+	ld a, [hl]
+	add a, MAP_ROW_H
+	ld [hl+], a ; hl = page y pos hi
+
+	ld a, [hl]
+	adc a, 0
+	ld [hl], a
+
+	pop hl
+	
+	dec b
+	ld de, act_size
+	add hl, de
+	jr nz, @act_loop REL
 
+	; TODO: adjust rectangles
+	ret
 
   ; writes scroll to scroll registers
   ; only call during blank
-- 
2.30.2