From: Lukas Krickl <lukas@krickl.dev>
Date: Wed, 1 Oct 2025 16:09:29 +0000 (+0200)
Subject: rectangle: optimized collision test by removing calls and pushes and calculating... 
X-Git-Url: https://git.krickl.dev/?a=commitdiff_plain;h=4b7fa5d7e0d2de1dcb2212c5280f7a763512c0a7;p=gbrg%2F.git

rectangle: optimized collision test by removing calls and pushes and calculating the points more directly
---

diff --git a/src/rectangle.s b/src/rectangle.s
index e8c8b77..99d3a10 100644
--- a/src/rectangle.s
+++ b/src/rectangle.s
@@ -159,20 +159,16 @@ rect_br:
 	;		a == 1: inside
 	;		a == 0: not inside
 rect_point_test:
-	; TODO: remove store hl
-	ld a, h
-	ld [h2], a
-	ld a, l
-	ld [l2], a
-
 	inc hl ; skip mask
 
 	; bottom left
 
 	; load bottom left point
 	ld a, [hl+]
+	; TODO: remove use of d2
+	ld [d2], a ; save y in d2
 	ld d, a ; d = y
-	ld a, [hl] 
+	ld a, [hl+] 
 	ld e, a ; e = x
 
 	ld a, b ; compare y
@@ -182,15 +178,17 @@ rect_point_test:
 	cp a, e
 	jr c, @no_collision REL
 
-	; TODO: remove restore hl
-	ld a, [h2]
-	ld h, a
-	ld a, [l2]
-	ld l, a
 
 	; top left
+
+	; get top left y point
+	ld a, [hl+]
 	push hl
-	call rect_tl
+	ld l, a ; TODO: remove use of l to avoid push
+	ld a, d
+	sub a, l ; y-height
+	capunderflow
+	ld d, a ; d = top left y
 	pop hl
 
 	ld a, b ; compare y points
@@ -203,9 +201,12 @@ rect_point_test:
 
 	
 	; top right
-	push hl
-	call rect_tr
-	pop hl
+
+	; get top right x
+	ld a, [hl]
+	add a, e ; e = x + width
+	capoverflow
+	ld e, a
 
 	ld a, b ; compare y
 	cp a, d
@@ -216,12 +217,15 @@ rect_point_test:
 
 
 	; bottom right 
-	push hl
-	call rect_br
-	pop hl
+
+	; remove height from y
+	; to get bottom right point
+	ld a, [d2] ; d2 = original y point
+	ld d, a
 
 	ld a, b ; compare y
-	jr c, @no_collision REL
+	cp a, d
+	jr nc, @no_collision REL
 	ld a, c ; compare x
 	cp a, e
 	jr nc, @no_collision REL