From b4d78a1bc16c5cb01189cff7f931a6478596e14a Mon Sep 17 00:00:00 2001
From: myT <mighty.cow@mailinator.com>
Date: Mon, 4 Dec 2017 20:50:45 +0100
Subject: [PATCH] fixed and unified Windows mouse wheel handling

---
 code/win32/win_input.cpp   | 39 +++++++++++++++++++-------------------
 code/win32/win_wndproc.cpp | 26 +------------------------
 2 files changed, 20 insertions(+), 45 deletions(-)

diff --git a/code/win32/win_input.cpp b/code/win32/win_input.cpp
index 3d081da..a7c2cd5 100644
--- a/code/win32/win_input.cpp
+++ b/code/win32/win_input.cpp
@@ -29,7 +29,7 @@ static cvar_t* in_noGrab;
 
 
 struct Mouse {
-	Mouse() : active(qfalse), wheel(0) {}
+	Mouse() : active(qfalse) {}
 
 	qbool IsActive() const { return active; }
 
@@ -42,7 +42,6 @@ protected:
 	void UpdateWheel( int delta );	// queues mouse wheel events if needed
 
 	qbool active;
-	int wheel;
 };
 
 static Mouse* mouse;
@@ -51,18 +50,18 @@ static qbool mouseSettingsSet = qfalse;
 
 void Mouse::UpdateWheel( int delta )
 {
-	wheel += delta;
-
-	while (wheel >= WHEEL_DELTA) {
-		WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELUP, qtrue, 0, NULL );
-		WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELUP, qfalse, 0, NULL );
-		wheel -= WHEEL_DELTA;
-	}
-
-	while (wheel <= -WHEEL_DELTA) {
-		WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELDOWN, qtrue, 0, NULL );
-		WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELDOWN, qfalse, 0, NULL );
-		wheel += WHEEL_DELTA;
+	if (delta > 0) {
+		while (delta >= WHEEL_DELTA) {
+			WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELUP, qtrue,  0, NULL );
+			WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELUP, qfalse, 0, NULL );
+			delta -= WHEEL_DELTA;
+		}
+	} else {
+		while (delta <= -WHEEL_DELTA) {
+			WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELDOWN, qtrue,  0, NULL );
+			WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELDOWN, qfalse, 0, NULL );
+			delta += WHEEL_DELTA;
+		}
 	}
 }
 
@@ -82,8 +81,6 @@ static rawmouse_t rawmouse;
 
 qbool rawmouse_t::Init()
 {
-	wheel = 0;
-
 	// Problems with the RIDEV_NOLEGACY flag:
 	// - When focusing the app while pressing a mouse button, the cursor becomes visible and stays so indefinitely
 	//   despite properly having done the repeated calls to ShowCursor(FALSE) until the counter is negative.
@@ -111,7 +108,6 @@ qbool rawmouse_t::Init()
 
 qbool rawmouse_t::Activate( qbool _active )
 {
-	wheel = 0;
 	active = _active;
 
 	return qtrue;
@@ -160,7 +156,7 @@ qbool rawmouse_t::ProcessMessage( UINT msg, WPARAM wParam, LPARAM lParam )
 	if (!ri.data.mouse.usButtonFlags) // no button or wheel transitions
 		return qfalse;
 
-	if (active && (ri.data.mouse.usButtonFlags & RI_MOUSE_WHEEL) != 0)
+	if ((ri.data.mouse.usButtonFlags & RI_MOUSE_WHEEL) != 0)
 		UpdateWheel( (SHORT)ri.data.mouse.usButtonData );
 
 	for (int i = 0; i < 5; ++i) {
@@ -204,7 +200,6 @@ void winmouse_t::UpdateWindowCenter()
 
 qbool winmouse_t::Activate( qbool _active )
 {
-	wheel = 0;
 	active = _active;
 
 	if (!_active)
@@ -219,8 +214,12 @@ qbool winmouse_t::Activate( qbool _active )
 
 qbool winmouse_t::ProcessMessage( UINT msg, WPARAM wParam, LPARAM lParam )
 {
-	if ( !active )
+	if ( !active ) {
+		if ( msg == WM_MOUSEWHEEL )
+			UpdateWheel( GET_WHEEL_DELTA_WPARAM(wParam) );
+
 		return qfalse;
+	}
 
 	UpdateWindowCenter();
 
diff --git a/code/win32/win_wndproc.cpp b/code/win32/win_wndproc.cpp
index 2b9e33e..4e5dfbc 100644
--- a/code/win32/win_wndproc.cpp
+++ b/code/win32/win_wndproc.cpp
@@ -214,30 +214,6 @@ LRESULT CALLBACK MainWndProc (
 {
 	switch (uMsg)
 	{
-
-	case WM_MOUSEWHEEL:
-		{
-			int i = (short)HIWORD(wParam);
-			// note: apparently the vista mouse driver often returns < WHEEL_DELTA
-			// but anyone running vista is a moron anyway, so fkit  :P
-			if (i > 0) {
-				while (i >= WHEEL_DELTA) {
-					WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELUP, qtrue, 0, NULL );
-					WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELUP, qfalse, 0, NULL );
-					i -= WHEEL_DELTA;
-				}
-			} else {
-				while (i <= -WHEEL_DELTA) {
-					WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELDOWN, qtrue, 0, NULL );
-					WIN_QueEvent( g_wv.sysMsgTime, SE_KEY, K_MWHEELDOWN, qfalse, 0, NULL );
-					i += WHEEL_DELTA;
-				}
-			}
-			// when an application processes the WM_MOUSEWHEEL message, it must return zero
-			return 0;
-		}
-		break;
-
 	case WM_CREATE:
 
 		g_wv.hWnd = hWnd;
@@ -373,7 +349,7 @@ LRESULT CALLBACK MainWndProc (
 	default:
 		// this is complicated because Win32 seems to pack multiple mouse events into
 		// one update sometimes, so we always check all states and look for events
-		if ( uMsg == WM_INPUT || (uMsg >= WM_MOUSEFIRST && uMsg <= WM_MOUSELAST) )
+		if ( uMsg == WM_INPUT || (uMsg >= WM_MOUSEFIRST && uMsg <= WM_MOUSELAST) || uMsg == WM_MOUSEWHEEL )
 			if ( IN_ProcessMessage(uMsg, wParam, lParam) )
 				return 0;
 		break;