From: Toni Wilen <twilen@winuae.net>
Date: Wed, 29 Aug 2018 17:52:27 +0000 (+0300)
Subject: Fix doublescan mode corruption.
X-Git-Tag: 4100~96
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=84ca82b4aa8893e33158d77b4da4e300cd14afb8;p=francis%2Fwinuae.git

Fix doublescan mode corruption.
---

diff --git a/custom.cpp b/custom.cpp
index dd28e26a..57527aba 100644
--- a/custom.cpp
+++ b/custom.cpp
@@ -9618,13 +9618,15 @@ static void hsync_handler_post (bool onvsync)
 	}
 	if (diw_change == 0) {
 		if (vpos >= first_planes_vpos && vpos <= last_planes_vpos) {
-			if (diwlastword > diwlastword_total) {
-				diwlastword_total = diwlastword;
+			int diwlastword_lores = diwlastword;
+			int diwfirstword_lores = diwfirstword;
+			if (diwlastword_lores > diwlastword_total) {
+				diwlastword_total = diwlastword_lores;
 				if (diwlastword_total > coord_diw_lores_to_window_x(hsyncstartpos * 2))
 					diwlastword_total = coord_diw_lores_to_window_x(hsyncstartpos * 2);
 			}
-			if (diwfirstword < diwfirstword_total) {
-				diwfirstword_total = diwfirstword;
+			if (diwfirstword_lores < diwfirstword_total) {
+				diwfirstword_total = diwfirstword_lores;
 				if (diwfirstword_total < coord_diw_lores_to_window_x(hsyncendpos * 2))
 					diwfirstword_total = coord_diw_lores_to_window_x(hsyncendpos * 2);
 				firstword_bplcon1 = bplcon1;
diff --git a/drawing.cpp b/drawing.cpp
index 65dcefe8..f081441d 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -90,10 +90,12 @@ static void lores_reset (void)
 	lores_factor = currprefs.gfx_resolution ? 2 : 1;
 	lores_set(currprefs.gfx_resolution);
 	if (doublescan > 0) {
-		if (lores_shift < 2)
-			lores_shift++;
+		int ls = lores_shift;
+		if (ls < 2) {
+			ls++;
+		}
 		lores_factor = 2;
-		lores_set(lores_shift);
+		lores_set(ls);
 	}
 	sprite_buffer_res = currprefs.gfx_resolution;
 	if (doublescan > 0 && sprite_buffer_res < RES_SUPERHIRES)