From 1f4594b45075c53990f6fc5cf4ae99759de87944 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Mon, 14 Sep 2020 21:10:34 +0200
Subject: [PATCH] - Duke: Only read keyboard input for movement when called for
 the actual tic.

Since the added values are not scaled, doing this per frame has the potential risk of achieving too high total velocity when combined with other means of input.
The change here was kept as simple as possible.
---
 source/games/duke/src/input.cpp | 103 +++++++++++++++++---------------
 1 file changed, 54 insertions(+), 49 deletions(-)

diff --git a/source/games/duke/src/input.cpp b/source/games/duke/src/input.cpp
index 0df2701f9..d48450de2 100644
--- a/source/games/duke/src/input.cpp
+++ b/source/games/duke/src/input.cpp
@@ -586,7 +586,7 @@ int getticssincelastupdate()
 //
 //---------------------------------------------------------------------------
 
-static void processMovement(player_struct *p, InputPacket &input, ControlInfo* const hidInput, double scaleFactor)
+static void processMovement(player_struct *p, InputPacket &input, ControlInfo* const hidInput, double scaleFactor, bool allowkeys)
 {
 	bool mouseaim = !(loc.actions & SB_AIMMODE);
 
@@ -608,21 +608,10 @@ static void processMovement(player_struct *p, InputPacket &input, ControlInfo* c
 	if (!in_mouseflip) input.q16horz = -input.q16horz;
 
 	input.q16horz -= FloatToFixed(scaleFactor * (hidInput->dpitch));
-	input.svel -= scaleFactor * (hidInput->dx * keymove);
-	input.fvel -= scaleFactor * (hidInput->dz * keymove);
+	input.svel -= xs_CRoundToInt(scaleFactor * hidInput->dx * keymove);
+	input.fvel -= xs_CRoundToInt(scaleFactor * hidInput->dz * keymove);
 
-	if (buttonMap.ButtonDown(gamefunc_Strafe))
-	{
-		if (!loc.svel)
-		{
-			if (buttonMap.ButtonDown(gamefunc_Turn_Left))
-				input.svel = keymove;
-
-			if (buttonMap.ButtonDown(gamefunc_Turn_Right))
-				input.svel = -keymove;
-		}
-	}
-	else
+	if (!buttonMap.ButtonDown(gamefunc_Strafe))
 	{
 		int tics = getticssincelastupdate();
 
@@ -644,44 +633,59 @@ static void processMovement(player_struct *p, InputPacket &input, ControlInfo* c
 
 	}
 
-	if (abs(loc.svel) < keymove)
+	if (allowkeys)
 	{
-		if (buttonMap.ButtonDown(gamefunc_Strafe_Left))
-			input.svel += keymove;
-
-		if (buttonMap.ButtonDown(gamefunc_Strafe_Right))
-			input.svel += -keymove;
-	}
-
-	if (abs(loc.fvel) < keymove)
-	{
-		if (isRR() && p->drink_amt >= 66 && p->drink_amt <= 87)
+		if (buttonMap.ButtonDown(gamefunc_Strafe))
 		{
-			if (buttonMap.ButtonDown(gamefunc_Move_Forward))
+			if (abs(loc.svel) < keymove)
 			{
-				input.fvel += keymove;
-				if (p->drink_amt & 1)
-					input.svel += keymove;
-				else
-					input.svel -= keymove;
-			}
+				if (buttonMap.ButtonDown(gamefunc_Turn_Left))
+					input.svel = keymove;
 
-			if (buttonMap.ButtonDown(gamefunc_Move_Backward))
-			{
-				input.fvel += -keymove;
-				if (p->drink_amt & 1)
-					input.svel -= keymove;
-				else
-					input.svel += keymove;
+				if (buttonMap.ButtonDown(gamefunc_Turn_Right))
+					input.svel = -keymove;
 			}
 		}
-		else
-		{
-			if (buttonMap.ButtonDown(gamefunc_Move_Forward))
-				input.fvel += keymove;
 
-			if (buttonMap.ButtonDown(gamefunc_Move_Backward))
-				input.fvel += -keymove;
+		if (abs(loc.svel) < keymove)
+		{
+			if (buttonMap.ButtonDown(gamefunc_Strafe_Left))
+				input.svel = keymove;
+
+			if (buttonMap.ButtonDown(gamefunc_Strafe_Right))
+				input.svel = -keymove;
+		}
+
+		if (abs(loc.fvel) < keymove)
+		{
+			if (isRR() && p->drink_amt >= 66 && p->drink_amt <= 87)
+			{
+				if (buttonMap.ButtonDown(gamefunc_Move_Forward))
+				{
+					input.fvel += keymove;
+					if (p->drink_amt & 1)
+						input.svel += keymove;
+					else
+						input.svel -= keymove;
+				}
+
+				if (buttonMap.ButtonDown(gamefunc_Move_Backward))
+				{
+					input.fvel += -keymove;
+					if (p->drink_amt & 1)
+						input.svel -= keymove;
+					else
+						input.svel += keymove;
+				}
+			}
+			else
+			{
+				if (buttonMap.ButtonDown(gamefunc_Move_Forward))
+					input.fvel += keymove;
+
+				if (buttonMap.ButtonDown(gamefunc_Move_Backward))
+					input.fvel -= keymove;
+			}
 		}
 	}
 }
@@ -982,7 +986,7 @@ static void FinalizeInput(int playerNum, InputPacket& input, bool vehicle)
 //
 //---------------------------------------------------------------------------
 
-static void GetInputInternal(InputPacket &locInput, ControlInfo* const hidInput)
+static void GetInputInternal(InputPacket &locInput, ControlInfo* const hidInput, bool allowkeys)
 {
 	auto const p = &ps[myconnectindex];
 
@@ -992,6 +996,7 @@ static void GetInputInternal(InputPacket &locInput, ControlInfo* const hidInput)
 		return;
 	}
 
+	// Todo: Handle this through SERVERINFO CVARs.
 	if (numplayers == 1)
 	{
 		setlocalplayerinput(p);
@@ -1015,7 +1020,7 @@ static void GetInputInternal(InputPacket &locInput, ControlInfo* const hidInput)
 	else
 	{
 		processInputBits(p, hidInput);
-		processMovement(p, input, hidInput, scaleAdjust);
+		processMovement(p, input, hidInput, scaleAdjust, allowkeys);
 		checkCrouchToggle(p);
 		FinalizeInput(myconnectindex, input, false);
 	}
@@ -1037,7 +1042,7 @@ static void GetInputInternal(InputPacket &locInput, ControlInfo* const hidInput)
 
 void GameInterface::GetInput(InputPacket* packet, ControlInfo* const hidInput)
 {
-	GetInputInternal(loc, hidInput);
+	GetInputInternal(loc, hidInput, packet != nullptr);
 	if (packet)
 	{
 		auto const pPlayer = &ps[myconnectindex];