From 9285d91918ab63b48422e06da7d6ec18103d278f Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Sun, 27 Sep 2020 08:30:28 +0200
Subject: [PATCH] - added timescale support from GZDoom.

---
 source/common/utility/i_time.cpp | 7 ++++---
 source/common/utility/i_time.h   | 1 +
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/source/common/utility/i_time.cpp b/source/common/utility/i_time.cpp
index f54c80d78..023860d81 100644
--- a/source/common/utility/i_time.cpp
+++ b/source/common/utility/i_time.cpp
@@ -48,10 +48,13 @@ static uint64_t CurrentFrameStartTime;
 static uint64_t FreezeTime;
 int GameTicRate = 35;	// make sure it is not 0, even if the client doesn't set it.
 
+double TimeScale = 1.0;
+
 static uint64_t GetClockTimeNS()
 {
 	using namespace std::chrono;
-	return (uint64_t)(duration_cast<nanoseconds>(steady_clock::now().time_since_epoch()).count());
+	if (TimeScale == 1.0) return (uint64_t)(duration_cast<nanoseconds>(steady_clock::now().time_since_epoch()).count());
+	else return (uint64_t)((duration_cast<microseconds>(steady_clock::now().time_since_epoch()).count()) * (uint64_t)(TimeScale * 1000));
 }
 
 static uint64_t MSToNS(unsigned int ms)
@@ -73,12 +76,10 @@ static int NSToBuildTic(uint64_t ns)
 {
 	return static_cast<int>(ns * 120 / 1'000'000'000);
 }
-
 static uint64_t TicToNS(int tic)
 {
 	return static_cast<uint64_t>(tic) * 1'000'000'000 / GameTicRate;
 }
-
 static uint64_t BuildTicToNS(int tic)
 {
 	return static_cast<uint64_t>(tic) * 1'000'000'000 / 120;
diff --git a/source/common/utility/i_time.h b/source/common/utility/i_time.h
index 78a399939..6f95795dd 100644
--- a/source/common/utility/i_time.h
+++ b/source/common/utility/i_time.h
@@ -3,6 +3,7 @@
 #include <stdint.h>
 
 extern int GameTicRate;
+extern double TimeScale;
 
 // Called by D_DoomLoop, sets the time for the current frame
 void I_SetFrameTime();