From 44cc4c2ad521e9fc50aa93f855101ca152a558a9 Mon Sep 17 00:00:00 2001
From: narzoul <narzoul@users.noreply.github.com>
Date: Mon, 18 Apr 2016 22:32:27 +0200
Subject: [PATCH] Disabled smooth scrolling

Prevents a visual artifact where the area that is supposed to scroll out of view
remains static during the smooth scrolling animation.
---
 DDrawCompat/CompatGdiScrollFunctions.cpp | 26 ++++++++++--------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/DDrawCompat/CompatGdiScrollFunctions.cpp b/DDrawCompat/CompatGdiScrollFunctions.cpp
index 08d7a1f..292a1cf 100644
--- a/DDrawCompat/CompatGdiScrollFunctions.cpp
+++ b/DDrawCompat/CompatGdiScrollFunctions.cpp
@@ -6,12 +6,8 @@
 
 namespace
 {
-	BOOL WINAPI scrollWindow(
-		_In_       HWND hWnd,
-		_In_       int  XAmount,
-		_In_       int  YAmount,
-		_In_ const RECT *lpRect,
-		_In_ const RECT *lpClipRect)
+	BOOL WINAPI scrollWindow(HWND hWnd, int XAmount, int YAmount,
+		const RECT* lpRect, const RECT* lpClipRect)
 	{
 		Compat::LogEnter("scrollWindow", hWnd, XAmount, YAmount, lpRect, lpClipRect);
 		BOOL result = CALL_ORIG_FUNC(ScrollWindow)(hWnd, XAmount, YAmount, lpRect, lpClipRect);
@@ -23,24 +19,24 @@ namespace
 		return result;
 	}
 
-	int WINAPI scrollWindowEx(
-		_In_        HWND   hWnd,
-		_In_        int    dx,
-		_In_        int    dy,
-		_In_  const RECT   *prcScroll,
-		_In_  const RECT   *prcClip,
-		_In_        HRGN   hrgnUpdate,
-		_Out_       LPRECT prcUpdate,
-		_In_        UINT   flags)
+	int WINAPI scrollWindowEx(HWND hWnd, int dx, int dy, const RECT* prcScroll, const RECT* prcClip,
+		HRGN hrgnUpdate, LPRECT prcUpdate, UINT flags)
 	{
 		Compat::LogEnter("scrollWindowEx",
 			hWnd, dx, dy, prcScroll, prcClip, hrgnUpdate, prcUpdate, flags);
+
+		if (flags & SW_SMOOTHSCROLL)
+		{
+			flags = LOWORD(flags ^ SW_SMOOTHSCROLL);
+		}
+
 		int result = CALL_ORIG_FUNC(ScrollWindowEx)(
 			hWnd, dx, dy, prcScroll, prcClip, hrgnUpdate, prcUpdate, flags);
 		if (ERROR != result)
 		{
 			CompatGdiScrollFunctions::updateScrolledWindow(hWnd);
 		}
+
 		Compat::LogLeave("scrollWindowEx",
 			hWnd, dx, dy, prcScroll, prcClip, hrgnUpdate, prcUpdate, flags) << result;
 		return result;