Ironsights

The goal of this tutorial is to create an ironsight system. It moves the origin of the weapon position up to the Player's eyes.
Here's a tutorial that implements a server-controlled Ironsight system: Adding Ironsights.
It might be better for MP mods, but works just as fine in SP.
== Intro ==
HL2DM and Singleplayer SDK
This could work with the Scratch as well. Normally all you have to do is replace hl2mp_ with sdk_xxx.cpp and you will find the right files to put it in.
This is a community project. The original code comes from this man: Cin.
He has credits to most of this code as it is now.
== hl2mp_weapon_parse.h (DM) or weapon_parse.h (Singleplayer) ==
Add this in the bottom of the file. Only add the lines with //ADDED behind.
public:
	//jorg40 - ironsight
	Vector m_expOffset; //ADDED
	QAngle m_expOriOffset; //ADDED
	int m_iPlayerDamage;
};
== hl2mp_weapon_parse.cpp (DM) or weapon_parse.cpp (Singleplayer) ==
Add this in the file.
void CHL2MPSWeaponInfo::Parse( KeyValues *pKeyValuesData, const char *szWeaponName )
{
...
 // this just saves off the data in the script file for later use
 KeyValues *pEt = pKeyValuesData->FindKey("ExpOffset");
 if (pEt)
 {
		m_expOffset.x = pEt->GetFloat("x", 0.0f);
		m_expOffset.y = pEt->GetFloat("y", 0.0f);
		m_expOffset.z = pEt->GetFloat("z", 0.0f);
		m_expOriOffset.x = pEt->GetFloat("xori", 0.0f);
		m_expOriOffset.y = pEt->GetFloat("yori", 0.0f);
		m_expOriOffset.z = pEt->GetFloat("zori", 0.0f);
 }
 else
 {
 m_expOffset = vec3_origin;
 m_expOriOffset.Init();
 }
...
}
== baseviewmodel_shared.cpp ==
Change in the beginning of the file so it looks like this
#include "cbase.h"
#include "baseviewmodel_shared.h"
#include "datacache/imdlcache.h"
#if defined( CLIENT_DLL )
#include "iprediction.h"
#include "prediction.h"
// cin: 070105 - ironsight mode changes
#include "convar.h"
#include "c_hl2mp_player.h"
#include "weapon_hl2mpbase.h"
#else
#include "vguiscreen.h"
#endif
// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"
Then under that add so it should look like this.
//THIS IS ALREADY IN THE CODE, just so you know where we are
#define VIEWMODEL_ANIMATION_PARITY_BITS 3
#define SCREEN_OVERLAY_MATERIAL "vgui/screens/vgui_overlay"
//ALL BELOW IS NEW
#if defined( CLIENT_DLL )
void ExpWpnTestOffset(ConVar *pConVar, char *pszString);
ConVar cl_exp_test_wpn_offset("cl_exp_test_wpn_offset", "0", 0, "Tests weapon offsets",
 (FnChangeCallback_t)ExpWpnTestOffset);
ConVar cl_exp_test_wpn_offset_x("cl_exp_test_wpn_offset_x", "0");
ConVar cl_exp_test_wpn_offset_y("cl_exp_test_wpn_offset_y", "0");
ConVar cl_exp_test_wpn_offset_z("cl_exp_test_wpn_offset_z", "0");
ConVar cl_exp_test_wpn_ori_offset_x("cl_exp_test_wpn_ori_offset_x", "0");
ConVar cl_exp_test_wpn_ori_offset_y("cl_exp_test_wpn_ori_offset_y", "0");
ConVar cl_exp_test_wpn_ori_offset_z("cl_exp_test_wpn_ori_offset_z", "0");
// cin: 070105 - applies existing weapon offsets when
// entering test mode (this will not be called upon
// weapon change, so beware)
// this mode should only be used for calibrating the
// ironsighted mode offests for a particular weapon
void ExpWpnTestOffset(ConVar *pConVar, char *pszString)
{
 CBasePlayer *pPlayer = UTIL_PlayerByIndex(engine->GetLocalPlayer());
 if (pPlayer)
 {
 CWeaponHL2MPBase *pWeapon = dynamic_cast<CWeaponHL2MPBase *>(pPlayer->GetActiveWeapon());
 if (pWeapon)
 {
 cl_exp_test_wpn_offset_x.SetValue(pWeapon->GetHL2MPWpnData().m_expOffset.x);
 cl_exp_test_wpn_offset_y.SetValue(pWeapon->GetHL2MPWpnData().m_expOffset.y);
 cl_exp_test_wpn_offset_z.SetValue(pWeapon->GetHL2MPWpnData().m_expOffset.z);
 cl_exp_test_wpn_ori_offset_x.SetValue(pWeapon->GetHL2MPWpnData().m_expOriOffset.x);
 cl_exp_test_wpn_ori_offset_y.SetValue(pWeapon->GetHL2MPWpnData().m_expOriOffset.y);
 cl_exp_test_wpn_ori_offset_z.SetValue(pWeapon->GetHL2MPWpnData().m_expOriOffset.z);
 }
 }
}
// last time ironsighted mode was toggled
float gIronsightedTime(0.0f);
// I bound this to a key for testing(i.e. bind [ ironsight_toggle)
CON_COMMAND(ironsight_toggle, "toggles ironsight mode for the current weapon")
{
 if (gpGlobals->curtime - gIronsightedTime < 0.5f)
 return;
 CBasePlayer *pPlayer = UTIL_PlayerByIndex(engine->GetLocalPlayer());
 if (pPlayer)
 {
 C_BaseViewModel *pVm = pPlayer->GetViewModel();
 if (pVm)
 {
		pPlayer->m_Local.m_iHideHUD ^= HIDEHUD_CROSSHAIR ;
 pVm->m_bExpSighted ^= true;
 gIronsightedTime = gpGlobals->curtime;
 }
 }
}
void CalcExpWpnOffsets(CBasePlayer *owner, Vector &pos, QAngle &ang)
{
 Vector forward, right, up, offset;
 // this is a simple test mode to help determine the proper values
 // to place in the weapon script
 if (cl_exp_test_wpn_offset.GetBool())
 {
 ang.x += cl_exp_test_wpn_ori_offset_x.GetFloat();
 ang.y += cl_exp_test_wpn_ori_offset_y.GetFloat();
 ang.z += cl_exp_test_wpn_ori_offset_z.GetFloat();
 offset.Init(cl_exp_test_wpn_offset_x.GetFloat(),
 cl_exp_test_wpn_offset_y.GetFloat(),
 cl_exp_test_wpn_offset_z.GetFloat());
 }
 else
 {
 CWeaponHL2MPBase *pWeapon = dynamic_cast<CWeaponHL2MPBase *>(ToHL2MPPlayer(owner)->GetActiveWeapon());
 if (pWeapon)
 {
 ang += pWeapon->GetHL2MPWpnData().m_expOriOffset;
 offset = pWeapon->GetHL2MPWpnData().m_expOffset;
 }
 }
 // get eye direction angles
 AngleVectors(ang, &forward, &right, &up);
 // apply the offsets
 pos += forward * offset.x;
 pos += right * offset.y;
 pos += up * offset.z;
}
#endif
Scroll down some and you will find the ViewModel::Spawn
Edit it to look like this:
void CBaseViewModel::Spawn( void )
{
	Precache( );
	SetSize( Vector( -8, -4, -2), Vector(8, 4, 2) );
	SetSolid( SOLID_NONE );
	#ifdef CLIENT_DLL
 // cin: 070105 - ironsighted mode changes
 m_bExpSighted = false;
 m_expFactor = 0.0f;
 gIronsightedTime = 0.0f; 
#endif
}
=== Animating the gun ===
Now while we are still in the file we need some more.
Look for void CBaseViewModel::CalcViewModelView.
Replace the whole function with this.
void CBaseViewModel::CalcViewModelView( CBasePlayer *owner, const Vector& eyePosition, const QAngle& eyeAngles )
{
 // UNDONE: Calc this on the server? Disabled for now as it seems unnecessary to have this info on the server
#if defined( CLIENT_DLL )
 QAngle vmangoriginal = eyeAngles;
 QAngle vmangles = eyeAngles;
 Vector vmorigin = eyePosition;
 CBaseCombatWeapon *pWeapon = m_hWeapon.Get();
 //Allow weapon lagging
 if ( pWeapon != NULL )
 {
#if defined( CLIENT_DLL )
 if ( !prediction->InPrediction() )
#endif
 {
 pWeapon->AddViewmodelBob( this, vmorigin, vmangles );
 CalcViewModelLag( vmorigin, vmangles, vmangoriginal );
 }
 }
#if defined( CLIENT_DLL )
 if ( !prediction->InPrediction() )
 {
 // Let the viewmodel shake at about 10% of the amplitude of the player's view
 vieweffects->ApplyShake( vmorigin, vmangles, 0.1 ); 
 }
#endif
 // cin: 070105 - ironsighted mode changes
 // get the wpn offsets
 CalcExpWpnOffsets(owner, vmorigin, vmangles);
 // get delta time for 1 sec interpolation and interpolate to/from positional offset
 float delta(gpGlobals->curtime - gIronsightedTime);
 m_expFactor = (m_bExpSighted) ? 
 (delta > 1.0f) ? 1.0f : delta :
 (delta > 1.0f) ? 0.0f : 1.0f - delta;
 Vector difPos(vmorigin - eyePosition);
 vmorigin = eyePosition + (difPos * m_expFactor);
 SetLocalOrigin(vmorigin);
 SetLocalAngles(vmangles);
#endif
}
Looks easy huh? What does it do then?
The delta variables says what is what.
1.0 is when the gun is fully ironsighted, and 0.0 says when it is not sighted at all. So this codes calculates the distance between and slide the gun from 0 to 1.
== baseviewmodel_shared.h ==
You need to add a couple of public defines here.
class CBaseViewModel : public CBaseAnimating
{
	DECLARE_CLASS( CBaseViewModel, CBaseAnimating );
public:
	bool m_bExpSighted; //ADDED
	float m_expFactor; //ADDED
	DECLARE_NETWORKCLASS();
	DECLARE_PREDICTABLE();
#if !defined( CLIENT_DLL )
	DECLARE_DATADESC();
#endif
== Extra ==
Some of you might think the gun is is moving up to the designated point a bit too slow, then here is the solution to it. Nothing hard nothing particular cool stuff, just 2 lines of code.
Look for this line: float gIronsightedTime(0.0f);
Below it add this.
float gMoveTime(0.1f); //Jorg40 - Seconds to use to move the model up to players view
Last line. Go to the delta
float delta(gpGlobals->curtime - gIronsightedTime);
Change it to look like this:
float delta((gpGlobals->curtime - gIronsightedTime) / gMoveTime);
Done! All we need to do is to change the script files.
== weapon_pistol.txt ==
Add this somewhere around the "WeaponData" section in the script file.
 ExpOffset
 {
 "x" "-15"
 "y" "-5.5"
 "z" "4.2"
 // "xori" "-2.9" //Does not work
 // "yori" "1.1" //Does not work
 // "zori" "2.0" // Does not work
 }
== Singleplayer Differences ==
To achieve this in singleplayer make the following alterations:
Replace:
CWeaponHL2MPBase *pWeapon = dynamic_cast<CWeaponHL2MPBase *>(pPlayer->GetActiveWeapon()); 
with
CBaseCombatWeapon *pWeapon = pPlayer->GetActiveWeapon(); 
Replace:
CWeaponHL2MPBase *pWeapon = dynamic_cast<CWeaponHL2MPBase *>(ToHL2MPPlayer(owner)->GetActiveWeapon());
with
CBaseCombatWeapon *pWeapon = owner->GetActiveWeapon(); 
Replace:
ConVar cl_exp_test_wpn_offset("cl_exp_test_wpn_offset", "0", 0, "Tests weapon offsets", (FnChangeCallback_t)ExpWpnTestOffset);
with 
ConVar cl_exp_test_wpn_offset("cl_exp_test_wpn_offset", "0", 0, "Tests weapon offsets", (FnChangeCallback)ExpWpnTestOffset);
Replace:
#include "convar.h"
#include "c_hl2mp_player.h"
#include "weapon_hl2mpbase.h"
with
#include "convar.h"
#include "c_baseplayer.h"
Replace:
pWeapon->GetHL2MPWpnData()
with
pWeapon->GetWpnData()
== Results ==
* An example image is shown on the right.
== Notes ==
Quote/Note from the real author:
How you set m_expFactor (time based interpolation is the easiest) and m_bExpSighted (button press) is up to you. Also , consider how you may pass this information to the server so ironsighted mode can be propagated over to other clients (i.e. other players will see that you're in ironsighted mode).
Also in-game, open console, write cl_exp and all the commands that are needed will show up.
Note from Pretador: Adding the Keybinds:
To add the keybind to toggle ironsight, open up your kb_act.
Under "#Valve_Combat_Title" Add:
"ironsight_toggle"		"#MOD_ironsight_toggle"
Then open your mod_english.txt in mod/resource and write:
"MOD_ironsight_toggle" "ironsight_toggle"
Category:Weapons programming