From 3823c77cb890cfe2618313080b9476d6ee15b6f6 Mon Sep 17 00:00:00 2001
From: Toni Wilen <twilen@winuae.net>
Date: Sun, 25 Jul 2021 21:27:12 +0300
Subject: [PATCH] PAL/NTSC scaling non-standard line count support.

---
 include/custom.h          |  2 +-
 od-win32/win32_scaler.cpp | 56 ++++++++++++++++++++++++++-------------
 2 files changed, 38 insertions(+), 20 deletions(-)

diff --git a/include/custom.h b/include/custom.h
index 777a8582..d510aae9 100644
--- a/include/custom.h
+++ b/include/custom.h
@@ -238,7 +238,7 @@ void customhack_put(struct customhack *ch, uae_u16 v, int hpos);
 uae_u16 customhack_get(struct customhack *ch, int hpos);
 extern void alloc_cycle_ext(int, int);
 extern void alloc_cycle_blitter(int hpos, uaecptr *ptr, int);
-extern bool ispal(void);
+extern bool ispal(int *lines);
 extern bool isvga(void);
 extern int current_maxvpos(void);
 extern struct chipset_refresh *get_chipset_refresh(struct uae_prefs*);
diff --git a/od-win32/win32_scaler.cpp b/od-win32/win32_scaler.cpp
index 153c81ad..5194ea86 100644
--- a/od-win32/win32_scaler.cpp
+++ b/od-win32/win32_scaler.cpp
@@ -182,16 +182,17 @@ static bool get_aspect(int monid, float *dstratiop, float *srcratiop, float *xmu
 				if (keep_aspect == 1)
 					dstratio = dstratio * 0.93f;
 			} else {
+				bool isp = ispal(NULL);
 				if (currprefs.ntscmode) {
 					dstratio = dstratio * 1.21f;
-					if (keep_aspect == 2 && ispal())
+					if (keep_aspect == 2 && isp)
 						dstratio = dstratio * 0.93f;
-					else if (keep_aspect == 1 && !ispal())
+					else if (keep_aspect == 1 && !isp)
 						dstratio = dstratio * 0.98f;
 				} else {
-					if (keep_aspect == 2 && ispal())
+					if (keep_aspect == 2 && isp)
 						dstratio = dstratio * 0.95f;
-					else if (keep_aspect == 1 && !ispal())
+					else if (keep_aspect == 1 && !isp)
 						dstratio = dstratio * 0.95f;
 				}
 			}
@@ -578,7 +579,7 @@ void getfilterrect2(int monid, RECT *sr, RECT *dr, RECT *zr, int dst_width, int
 					ww = currprefs.gfx_xcenter_size;
 				if (currprefs.gfx_ycenter_size >= 0)
 					hh = currprefs.gfx_ycenter_size;
-				if (scalemode == oscalemode) {
+				if (scalemode == oscalemode && !useold) {
 					int oldwinw = gmc->gfx_size_win.width;
 					int oldwinh = gmc->gfx_size_win.height;
 					gmh->gfx_size_win.width = ww;
@@ -668,22 +669,39 @@ cont:
 
 	}
 
-	if (currprefs.ntscmode) {
-		if (palntscadjust && ispal()) {
-			dstratio = dstratio * (625 / 525.0);
+	{
+		float palntscratio = dstratio;
+		int l = 0;
+		bool isp = ispal(&l);
+		if (abs(l - 262) <= 5) {
+			l = 262;
 		}
-		if (keep_aspect == 2 && ispal ())
-			dstratio = dstratio * 0.93f;
-		else if (keep_aspect == 1 && !ispal ())
-			dstratio = dstratio * 0.98f;
-	} else {
-		if (palntscadjust && !ispal()) {
-			dstratio = dstratio * (625 / 525.0);
+		if (abs(l - 312) <= 5) {
+			l = 312;
+		}
+		float ll = l * 2 + 1;
+		if (currprefs.ntscmode) {
+			if (palntscadjust && isp) {
+				palntscratio = palntscratio * (ll / 525.0);
+			}
+			if (keep_aspect == 2 && isp) {
+				palntscratio = palntscratio * 0.93f;
+			} else if (keep_aspect == 1 && !isp) {
+				palntscratio = palntscratio * 0.98f;
+			}
+		} else {
+			if (palntscadjust && !isp) {
+				palntscratio = palntscratio * (625.0 / ll);
+			}
+			if (keep_aspect == 2 && isp) {
+				palntscratio = palntscratio * 0.95f;
+			} else if (keep_aspect == 1 && !isp) {
+				palntscratio = palntscratio * 0.95f;
+			}
+		}
+		if (palntscratio != dstratio) {
+			ymult = ymult * palntscratio / dstratio;
 		}
-		if (keep_aspect == 2 && ispal ())
-			dstratio = dstratio * 0.95f;
-		else if (keep_aspect == 1 && !ispal ())
-			dstratio = dstratio * 0.95f;
 	}
 
 	if (srcratio > dstratio) {
-- 
2.47.3