- Fixed: LocalViewPitch could overflow and wrap around when a netgame stalls.

SVN r459 (trunk)

docs/rh-log.txt

@@ -1,4 +1,5 @@
 January 22, 2007
+- Fixed: LocalViewPitch could overflow and wrap around when a netgame stalls.
 - Changed the vertheight and rounding-error-checking code in
   DCanvas::DrawTexture() to calculate off the actual bottom of the image
   instead of the height, improving precision. Now the scaled status bar is

src/d_net.cpp

@@ -704,10 +704,11 @@ void GetPackets (void)
 		netnode = doomcom.remotenode;
 		netconsole = playerfornode[netnode] & ~PL_DRONE;
 
-		// [RH] Get "ping" times
+		// [RH] Get "ping" times - totally useless, since it's bound to the frequency
+		// packets go out at.
 		lastrecvtime[netconsole] = currrecvtime[netconsole];
 		currrecvtime[netconsole] = I_MSTime ();
-		
+
 		// check for exiting the game
 		if (netbuffer[0] & NCMD_EXIT)
 		{

src/g_game.cpp

@@ -646,13 +646,34 @@ void G_AddViewPitch (int look)
 	{
 		return;
 	}
+	look <<= 16;
 	if (dmflags & DF_NO_FREELOOK)
 	{
 		LocalViewPitch = 0;
 	}
-	else
+	else if (look > 0)
 	{
-		LocalViewPitch += look << 16;
+		// Avoid overflowing
+		if (LocalViewPitch + look <= LocalViewPitch)
+		{
+			LocalViewPitch = 0x78000000;
+		}
+		else
+		{
+			LocalViewPitch = MIN(LocalViewPitch + look, 0x78000000);
+		}
+	}
+	else if (look < 0)
+	{
+		// Avoid overflowing
+		if (LocalViewPitch + look >= LocalViewPitch)
+		{
+			LocalViewPitch = -0x78000000;
+		}
+		else
+		{
+			LocalViewPitch = MAX(LocalViewPitch + look, -0x78000000);
+		}
 	}
 	if (look != 0)
 	{

src/r_main.cpp

@@ -877,7 +877,34 @@ void R_InterpolateView (player_t *player, fixed_t frac, InterpolationViewer *ivi
 		!LocalKeyboardTurner)
 	{
 		viewangle = iview->nviewangle + (LocalViewAngle & 0xFFFF0000);
-		viewpitch = clamp<int> (iview->nviewpitch - (LocalViewPitch & 0xFFFF0000), -ANGLE_1*MAX_UP_ANGLE, +ANGLE_1*MAX_DN_ANGLE);
+
+		fixed_t delta = -(signed)(LocalViewPitch & 0xFFFF0000);
+
+		viewpitch = iview->nviewpitch;
+		if (delta > 0)
+		{
+			// Avoid overflowing viewpitch (can happen when a netgame is stalled)
+			if (viewpitch + delta <= viewpitch)
+			{
+				viewpitch = +ANGLE_1*MAX_DN_ANGLE;
+			}
+			else
+			{
+				viewpitch = MIN(viewpitch + delta, +ANGLE_1*MAX_DN_ANGLE);
+			}
+		}
+		else if (delta < 0)
+		{
+			// Avoid overflowing viewpitch (can happen when a netgame is stalled)
+			if (viewpitch + delta >= viewpitch)
+			{
+				viewpitch = -ANGLE_1*MAX_UP_ANGLE;
+			}
+			else
+			{
+				viewpitch = MAX(viewpitch + delta, -ANGLE_1*MAX_UP_ANGLE);
+			}
+		}
 	}
 	else
 	{