Ensure view interpolates between T-1 to T

src/p_tick.c

@@ -23,6 +23,7 @@
 #include "lua_hook.h"
 #include "m_perfstats.h"
 #include "i_system.h" // I_GetPreciseTime
+#include "r_main.h"
 #include "r_fps.h"
 
 // Object place
@@ -771,8 +772,30 @@ void P_Ticker(boolean run)
 
 	if (run)
 	{
+		player_t *player1;
+
 		R_UpdateLevelInterpolators();
 		R_UpdateViewInterpolation();
+
+		// Hack: ensure newview is assigned every tic.
+		// Ensures view interpolation is T-1 to T in poor network conditions
+		// We need a better way to assign view state decoupled from game logic
+		player1 = &players[displayplayer];
+		if (player1->mo && skyboxmo[0] && cv_skybox.value)
+		{
+			R_SkyboxFrame(player1);
+		}
+		R_SetupFrame(player1);
+
+		if (splitscreen)
+		{
+			player_t *player2 = &players[secondarydisplayplayer];
+			if (player2->mo && skyboxmo[0] && cv_skybox.value)
+			{
+				R_SkyboxFrame(player2);
+			}
+			R_SetupFrame(player2);
+		}
 	}
 
 	P_MapEnd();