Interp: do not update view interpolation state during sped-up tics

- If you called R_ResetViewInterpolation once but G_Ticker
  got called more than once, then the effect of
  R_ResetViewInterpolation would be cancelled
- This should be a comprehensive solution to the titlemap
  camera bug
- Multiple tests:
  - -skipintro
  - -warp, then exit to title
  - map command, then exit to title
  - Wait for attract demo, then skip and exit to title

src/d_clisrv.c

@@ -66,6 +66,7 @@
 #include "music.h"
 #include "k_bans.h"
 #include "sanitize.h"
+#include "r_fps.h"
 
 // cl loading screen
 #include "v_video.h"
@@ -6045,6 +6046,8 @@ boolean TryRunTics(tic_t realtics)
 
 	if (ticking)
 	{
+		boolean tickInterp = true;
+
 		// run the count * tics
 		while (neededtic > gametic)
 		{
@@ -6073,7 +6076,17 @@ boolean TryRunTics(tic_t realtics)
 					P_PostLoadLevel();
 				}
 
-				G_Ticker((gametic % NEWTICRATERATIO) == 0);
+				boolean run = (gametic % NEWTICRATERATIO) == 0;
+
+				if (run && tickInterp)
+				{
+					// Update old view state BEFORE ticking so resetting
+					// the old interpolation state from game logic works.
+					R_UpdateViewInterpolation();
+					tickInterp = false; // do not update again in sped-up tics
+				}
+
+				G_Ticker(run);
 			}
 
 			if (Playing() && netgame && (gametic % TICRATE == 0))

src/p_tick.c

@@ -852,13 +852,6 @@ void P_Ticker(boolean run)
 		}
 	}
 
-	if (run)
-	{
-		// Update old view state BEFORE ticking so resetting
-		// the old interpolation state from game logic works.
-		R_UpdateViewInterpolation();
-	}
-
 	if (objectplacing)
 	{
 		if (OP_FreezeObjectplace())