From e75561b3821355593867761fe013847c0311d282 Mon Sep 17 00:00:00 2001
From: Night Owl <sepulkarium45@yahoo.com>
Date: Thu, 12 Apr 2018 00:43:25 +0500
Subject: [PATCH] Add autojump from OpenAG.

---
 cl_dll/input.cpp      | 30 ++++++++++++++++++++++++++++++
 pm_shared/pm_shared.c | 10 ++++++++++
 2 files changed, 40 insertions(+)

diff --git a/cl_dll/input.cpp b/cl_dll/input.cpp
index 2e07f7ac..2bd27719 100644
--- a/cl_dll/input.cpp
+++ b/cl_dll/input.cpp
@@ -73,7 +73,14 @@ cvar_t	*cl_yawspeed;
 cvar_t	*cl_pitchspeed;
 cvar_t	*cl_anglespeedkey;
 cvar_t	*cl_vsmoothing;
+cvar_t	*cl_autojump;
 
+extern "C"
+{
+	int g_onground = false;
+	int g_inwater = false;
+	int g_walking = true; // Movetype == MOVETYPE_WALK. Filters out noclip, being on ladder, etc.
+}
 /*
 ===============================================================================
 
@@ -842,6 +849,28 @@ void DLLEXPORT CL_CreateMove( float frametime, struct usercmd_s *cmd, int active
 	//
 	cmd->buttons = CL_ButtonBits( 1 );
 
+	{
+		static bool s_jump_was_down_last_frame = false;
+
+		if( cl_autojump->value != 0.0f )
+		{
+			bool should_release_jump = ( !g_onground && !g_inwater && g_walking );
+
+			/*
+			 * Spam pressing and releasing jump if we're stuck in a spot where jumping still results in
+			 * being onground in the end of the frame. Without this check, +jump would remain held and
+			 * when the player exits this spot they would have to release and press the jump button to
+			 * start jumping again. This also helps with exiting water or ladder right onto the ground.
+			*/
+			if( s_jump_was_down_last_frame && g_onground && !g_inwater && g_walking )
+				should_release_jump = true;
+
+			if( should_release_jump )
+				cmd->buttons &= ~IN_JUMP;
+		}
+
+		s_jump_was_down_last_frame = ( ( cmd->buttons & IN_JUMP ) != 0 );
+	}
 	// Using joystick?
 	if( in_joystick->value )
 	{
@@ -1099,6 +1128,7 @@ void InitInput( void )
 	cl_pitchdown		= gEngfuncs.pfnRegisterVariable( "cl_pitchdown", "89", 0 );
 
 	cl_vsmoothing		= gEngfuncs.pfnRegisterVariable( "cl_vsmoothing", "0.05", FCVAR_ARCHIVE );
+	cl_autojump		= gEngfuncs.pfnRegisterVariable( "cl_autojump", "1", FCVAR_ARCHIVE );
 
 	m_pitch			= gEngfuncs.pfnRegisterVariable( "m_pitch","0.022", FCVAR_ARCHIVE );
 	m_yaw			= gEngfuncs.pfnRegisterVariable( "m_yaw","0.022", FCVAR_ARCHIVE );
diff --git a/pm_shared/pm_shared.c b/pm_shared/pm_shared.c
index 641876eb..f477f197 100644
--- a/pm_shared/pm_shared.c
+++ b/pm_shared/pm_shared.c
@@ -2734,6 +2734,16 @@ void PM_Move( struct playermove_s *ppmove, int server )
 	{
 		pmove->friction = 1.0f;
 	}
+
+#ifdef CLIENT_DLL
+	extern int g_onground;
+	extern int g_inwater;
+	extern int g_walking;
+
+	g_onground = ( pmove->onground != -1 );
+	g_inwater = ( pmove->waterlevel > 1 );
+	g_walking = ( pmove->movetype == MOVETYPE_WALK );
+#endif
 }
 
 int PM_GetInfo( int ent )