From: Lukas Krickl <lukas@krickl.dev>
Date: Fri, 26 Sep 2025 08:11:11 +0000 (+0200)
Subject: actor: collision now uses pre-computed points for the source rectangle
X-Git-Url: https://git.krickl.dev/?a=commitdiff_plain;h=7ac9179a5a808364ec7cc8e03e3d45b41aad4e68;p=gbrg%2F.git

actor: collision now uses pre-computed points for the source rectangle
---

diff --git a/src/actor.s b/src/actor.s
index aa7fad3..e13760a 100644
--- a/src/actor.s
+++ b/src/actor.s
@@ -173,25 +173,29 @@ actor_write_default_collider:
 	; performs a single test case
 	; inputs:
 	;		tmp_rect: new target rect
+	;		de: ptr to 2 coordinates (y/x) e.g. tmp_rect_points
 	;		$1: rect_bl/tl/br/tr call
 	;		hl: rectangle to compare to
-	;	preserves all registers
-	; jumps to $2 on collision
+	; jumps to $1 on collision
+	;	returns:
+	;		de: de+=2
+	; preserves: hl
 #macro actor_test_movement_corner	
-		push_all
-
+		ld a, [de]
+		inc de
+		ld b, a
+		ld a, [de]
+		inc de
+		ld c, a
+		; bc = point
+		
 		push hl
-		ld hl, tmp_rect
-		call $1 ; bc = bottom left point
 		push de
-		pop bc
-		pop hl ; hl = test rect
-
 		call rect_point_test
+		pop de
+		pop hl
 		cp a, 1
-		jp z, $2
-
-		pop_all
+		jp z, $1
 #endmacro
 
 	; tests movement against all collision rectangles
@@ -341,62 +345,34 @@ actor_test_movement_write_points:
 	;		tmp_act_direction: direction
 	;		tmp_rect: new collision rectangle
 	;	  tmp_rect_mask: mask to test agains
+	;		tmp_rect_points: 2 rectangle points base don tmp_rect and the 
+	;										 chosen direction
 	;   hl: rectangle to test
 	;	returns:
 	; 		a: 1 collision
 	;			a: 0 no collision
+	;	preserves: all registers 
 actor_test_rect:
+	push_all
+
 	; pre-filter rectangle mask
 	ld a, [tmp_rect_mask]
 	call rect_test_mask
-	ret z
+	jp z, @no_collision
 	
-	ld a, [tmp_act_direction]
-	cp a, DIRUP
-	jp z, @up
-	cp a, DIRDOWN
-	jp z, @down
-	cp a, DIRLEFT
-	jp z, @left
-	cp a, DIRRIGHT
-	jp z, @right
-
-	; default: test all corners of tmp_rect 
-
-	actor_test_movement_corner rect_bl, @rect_collision
-	actor_test_movement_corner rect_br, @rect_collision
-	actor_test_movement_corner rect_tl, @rect_collision
-	actor_test_movement_corner rect_tr, @rect_collision
+	; test the first 2 points in tmp_rect_points
+	ld de, tmp_rect_points
+	actor_test_movement_corner @rect_collision
+	actor_test_movement_corner @rect_collision
 
 @no_collision:
+	pop_all
 	xor a, a
 	ret
 @rect_collision:
-	; actor_test_movement does not pop all when the check 
-	; passes
 	pop_all
 	ld a, 1
 	ret
-@up:
-	actor_test_movement_corner rect_tl, @rect_collision
-	actor_test_movement_corner rect_tr, @rect_collision
-	xor a, a
-	ret
-@down:
-	actor_test_movement_corner rect_bl, @rect_collision
-	actor_test_movement_corner rect_br, @rect_collision
-	xor a, a
-	ret
-@right:
-	actor_test_movement_corner rect_br, @rect_collision
-	actor_test_movement_corner rect_tr, @rect_collision
-	xor a, a
-	ret
-@left:
-	actor_test_movement_corner rect_bl, @rect_collision
-	actor_test_movement_corner rect_tl, @rect_collision
-	xor a, a
-	ret
 	
 	; calls collision resolution 
 	; inputs:
diff --git a/src/wram.s b/src/wram.s
index 5ba82e9..048107a 100644
--- a/src/wram.s
+++ b/src/wram.s
@@ -87,7 +87,7 @@ tmp_rect_mask: .adv 1
 	; temporary points 
 	; has enough space for 4 points
 	; store pre-calculated points here for collision checking
-tmp_rect_points: .adv 4 * 2
+tmp_rect_points: .adv 8 
 	
 	; temporary actor direction mask
 tmp_act_direction: .adv 1