From: Lukas Krickl <lukas@krickl.dev>
Date: Sun, 21 Sep 2025 15:46:04 +0000 (+0200)
Subject: debug: wip rectangle debug renderer
X-Git-Url: https://git.krickl.dev/?a=commitdiff_plain;h=89b050e6589ab8f5873e910046071dc410f8c903;p=gbrg%2F.git

debug: wip rectangle debug renderer
---

diff --git a/src/debug.s b/src/debug.s
index 558c5b9..929c22b 100644
--- a/src/debug.s
+++ b/src/debug.s
@@ -1,3 +1,5 @@
+#define DBG_MARKER_TILE 0x80
+
 debug_routines:
 	dw dbg_nop
 	dw dbg_rect_draw
@@ -8,6 +10,12 @@ dbg_nop:
 	
 	; inits the debug interface
 dbg_init:
+	; set first rectangle to display
+	ld a, rectangles LO
+	ld [dbg_rect], a
+	ld a, rectangles HI
+	ld [dbg_rect+1], a
+	
 	ret
 
 	; updates debug options
@@ -65,4 +73,116 @@ dbg_update:
 	; keys:
 	;		up + select: cycle to next debug rectangle
 dbg_rect_draw:
+	; TODO: add rectangle cycles
+
+	; draw each corner of the rectangle if it is not 0
+	ld a, [dbg_rect]
+	ld e, a
+	ld a, [dbg_rect+1]
+	ld d, a
+
+	; de = rectangle ptr
+	
+	; if flags are 0 we exit
+	ld a, [de]
+	cp a, 0
+	jp z, @rect_not_alloced
+	
+	push de
+	ld a, 4
+	call oamalloc
+	pop de
+
+	; hl = oam
+	inc de ; de = y position
+
+	ld a, [de]
+	add a, OBJ_OFF_Y
+	ld b, a ; b = y
+	
+	inc de
+	ld a, [de]
+	add a, OBJ_OFF_X
+	ld c, a ; c = x
+	inc de ; de = height
+	
+	; write top left y
+	ld a, b
+	ld [hl+], a
+
+	; write top left x
+	ld a, c
+	ld [hl+], a
+
+	; write tile
+	ld a, DBG_MARKER_TILE
+	ld [hl+], a
+
+	; write flags
+	xor a, a
+	ld [hl+], a
+	
+	; write top left y
+	ld a, [de] ; a = heigth
+	sub a, b ; height -  y
+	add a, 16 + OBJ_OFF_Y ; off by one obj height so it won't end up off-screen 
+	ld [hl+], a
+
+	; write top left x
+	ld a, c 
+	ld [hl+], a
+	
+	; write tile
+	ld a, DBG_MARKER_TILE
+	ld [hl+], a
+
+	; write flags
+	xor a, a
+	ld [hl+], a
+
+	; write bottom right y
+	inc de ; de = width
+	ld a, b ; a = y
+	ld [hl+], a
+
+	; write bottomt right x
+	ld a, [de]
+	sub a, c
+	add a, OBJ_OFF_X + 8 
+	ld [hl+], a
+
+	; write tile 
+	ld a, DBG_MARKER_TILE
+	ld [hl+], a
+
+	; write flags
+	xor a, a
+	ld [hl+], a
+
+	dec de ; de = height
+
+	; write top right y
+	ld a, [de] ; a = height
+	sub a, b ; height - y
+	add a, 16 + OBJ_OFF_Y ; off by one obj height so it won't end up off-screen 
+	ld [hl+], a
+
+	; write top left x
+	inc de ; de = width
+	ld a, [de]
+	sub a, c
+	add a, OBJ_OFF_X + 8 
+	ld [hl+], a
+
+	; write tile 
+	ld a, DBG_MARKER_TILE
+	ld [hl+], a
+
+	; write flags
+	xor a, a
+	ld [hl+], a
+
+
+	ret
+@rect_not_alloced:
 	ret
diff --git a/src/rectangle.s b/src/rectangle.s
index 74a0ee1..3e18848 100644
--- a/src/rectangle.s
+++ b/src/rectangle.s
@@ -111,4 +111,12 @@ rect_test:
 	;		a == 0: not inside
 rect_point_test:
 	ret
+
 	
+	; removes a rectangle
+	; inputs:
+	;		de: rectangle
+rect_despawn:
+	xor a, a
+	ld [de], a
+	ret
diff --git a/src/update.s b/src/update.s
index 788b685..016a04b 100644
--- a/src/update.s
+++ b/src/update.s
@@ -36,14 +36,15 @@ update:
   ; reset objects
   call oamfree_all 
 
-	call dbg_update
 
 	; load current sate routine
 	ld a, [game_state]
 	ld l, a
 	ld a, [game_state+1]
 	ld h, a
-	jp hl
+	call_hl
+	
+	call dbg_update
   
   ret
 
diff --git a/src/video.s b/src/video.s
index 5611a83..4f73deb 100644
--- a/src/video.s
+++ b/src/video.s
@@ -129,6 +129,12 @@ scroll_up_adjust:
 		ld a, [hl]
 		inc a
 		ld [hl], a
+	
+		; check if off-screen
+		pop de
+		push de
+		cp a, 0x70 
+		call nc, rect_despawn
 		
 		pop hl
 		dec b
diff --git a/tiles/bank8800.inc b/tiles/bank8800.inc
index 4022f01..e2f301c 100644
--- a/tiles/bank8800.inc
+++ b/tiles/bank8800.inc
@@ -1,8 +1,8 @@
 ; tile 0
-.chr 32000000
-.chr 10000000
-.chr 00000000
-.chr 00000000
+.chr 32130000
+.chr 13330000
+.chr 23000000
+.chr 33000000
 .chr 00000000
 .chr 00000000
 .chr 00000000