From 45fd2946d98def85a4e471b7327a7dfa73e5e5fd Mon Sep 17 00:00:00 2001
From: Waccoon <105848526+Waccoon@users.noreply.github.com>
Date: Tue, 24 May 2022 03:55:02 -0400
Subject: [PATCH] Update drawing.cpp

Update EHB logic so palette mirroring will be correct with A1000 early Denise chip.  With AGA chipset, bplehb may be zero (uses color registers 32-63), but for OCS/ECS it must be -1 (mirrors color registers 0-31).  Logic assumes that OCS Denise with EHB support cannot disable its EHB colors.
---
 drawing.cpp | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drawing.cpp b/drawing.cpp
index 12d492b7..748cdd4f 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -3112,10 +3112,15 @@ static void pfield_expand_dp_bplcon(void)
 	bplplanecnt = dp_for_drawing->nr_planes;
 	bplham = dp_for_drawing->ham_seen;
 	bplehb = dp_for_drawing->ehb_seen;
-	if (ecs_denise && (dp_for_drawing->bplcon2 & 0x0200)) {
-		bplehb = 0;
-		if (!aga_mode)
-			bplehb = -1;
+	if (ecs_denise) {
+		// Check for KillEHB bit in ECS/AGA
+		if (dp_for_drawing->bplcon2 & 0x0200) {
+			bplehb = 0;
+			if (!aga_mode)
+				bplehb = -1;
+		}
+	} else if ((currprefs.cs_denisenoehb)) {
+		bplehb = -1;
 	}
 	bplcolorburst = (dp_for_drawing->bplcon0 & 0x200) != 0;
 	if (!bplcolorburst)
-- 
2.47.3