From 358f0912fcaf20049978a2f142d20439cc9b8e5a Mon Sep 17 00:00:00 2001
From: Daniel Borges <msk@lywenn.eu.org>
Date: Mon, 31 Dec 2018 14:26:57 +0100
Subject: [PATCH] it's not necessary to load mask into A, and can use direct
 value too! 11 => 10 VBLs

---
 Code/main.asm | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/Code/main.asm b/Code/main.asm
index a0f0820..a4be0d9 100644
--- a/Code/main.asm
+++ b/Code/main.asm
@@ -37,8 +37,7 @@ AddLiveNeighbors: MACRO
 	; load current 2x2 cell and mask out bits that are not neighbors
 	ld c, LOW(Cells + \1)
 	ld a, [$FF00+c]
-	ld b, \2
-	and a, b
+	and a, \2
 	
 	; count bits set
 	ld e, a
@@ -71,14 +70,11 @@ Conway: MACRO
 	AddLiveNeighbors (1 + (\2 + 1) % 8), \4
 	AddLiveNeighbors (1 + (\2 + 2) % 8), \5
 	
-	; load current group mask
-	ld b, (~\1) & $F
-	
 	; load current cell group
 	ldh a, [Cells]
 	
 	; mask data
-	and a, b
+	and a, (~\1) & $F
 	
 	; put alive neighbors in A
 	ld a, h
@@ -94,7 +90,7 @@ Conway: MACRO
 .writealive\@
 	; add mask to result
 	ld a, l
-	add a, b
+	add a, (~\1) & $F
 	ld l, a
 	jr .writedead\@