From 97feb483ab1c78cc6d88b891c80e5fa481afb9a2 Mon Sep 17 00:00:00 2001
From: Mitchell Richters <mjr4077au@gmail.com>
Date: Fri, 28 Aug 2020 15:27:16 +1000
Subject: [PATCH] - Set frame-time as close to the buffer swap as possible, and
 calculate smoothratio for Duke/SW as late as possible.

* Micro-optimisation, but was getting a very occasional jitter in Duke 3D that seems to have gone with this.
---
 source/build/src/engine.cpp        | 1 +
 source/core/gamecontrol.cpp        | 1 -
 source/games/duke/src/gameloop.cpp | 3 +--
 source/sw/src/game.cpp             | 4 ++--
 4 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/source/build/src/engine.cpp b/source/build/src/engine.cpp
index 42ce85175..01086eb35 100644
--- a/source/build/src/engine.cpp
+++ b/source/build/src/engine.cpp
@@ -2724,6 +2724,7 @@ void videoNextPage(void)
 {
  	g_beforeSwapTime = I_msTimeF();
 	videoShowFrame(0);
+    I_SetFrameTime();
 
     omdtims = mdtims;
     mdtims = I_msTime();
diff --git a/source/core/gamecontrol.cpp b/source/core/gamecontrol.cpp
index 2f53733b4..14b69bf59 100644
--- a/source/core/gamecontrol.cpp
+++ b/source/core/gamecontrol.cpp
@@ -941,7 +941,6 @@ void app_loop()
 			TickSubsystems();
 			twod->SetSize(screen->GetWidth(), screen->GetHeight());
 			twodpsp.SetSize(screen->GetWidth(), screen->GetHeight());
-			I_SetFrameTime();
 
 			handleevents();
 			updatePauseStatus();
diff --git a/source/games/duke/src/gameloop.cpp b/source/games/duke/src/gameloop.cpp
index c0ec5f9bc..5c3dd9455 100644
--- a/source/games/duke/src/gameloop.cpp
+++ b/source/games/duke/src/gameloop.cpp
@@ -353,8 +353,6 @@ bool GameTicker()
 		}
 	}
 
-	double const smoothRatio = playrunning() ? I_GetTimeFrac() * MaxSmoothRatio : MaxSmoothRatio;
-
 	gameupdatetime.Unclock();
 
 	if (ps[myconnectindex].gm & (MODE_EOL | MODE_RESTART))
@@ -370,6 +368,7 @@ bool GameTicker()
 	drawtime.Reset();
 	drawtime.Clock();
 	S_Update();
+	double const smoothRatio = playrunning() ? I_GetTimeFrac() * MaxSmoothRatio : MaxSmoothRatio;
 	displayrooms(screenpeek, smoothRatio);
 	displayrest(smoothRatio);
 	drawtime.Unclock();
diff --git a/source/sw/src/game.cpp b/source/sw/src/game.cpp
index edf851112..dd9a5ba29 100644
--- a/source/sw/src/game.cpp
+++ b/source/sw/src/game.cpp
@@ -788,11 +788,11 @@ void GameTicker(void)
                 MoveTicker();
             }
 
-            smoothratio = I_GetTimeFrac() * MaxSmoothRatio;
-
             // Get input again to update q16ang/q16horiz.
             if (!PedanticMode)
                 getinput(&loc, TRUE);
+
+            smoothratio = I_GetTimeFrac() * MaxSmoothRatio;
         }
 
         drawscreen(Player + screenpeek, smoothratio);