Fix line endings. WHAMMY.

1 files changed, 1895 insertions, 1895 deletions

diff --git a/mp/src/game/server/physconstraint.cpp b/mp/src/game/server/physconstraint.cpp
index 3d1cc1f1..8fa25cdd 100644
--- a/mp/src/game/server/physconstraint.cpp
+++ b/mp/src/game/server/physconstraint.cpp
@@ -1,1895 +1,1895 @@
-//========= Copyright Valve Corporation, All rights reserved. ============//

-//

-// Purpose: Physics constraint entities

-//

-// $NoKeywords: $

-//===========================================================================//

-

-#include "cbase.h"

-#include "physics.h"

-#include "entityoutput.h"

-#include "engine/IEngineSound.h"

-#include "igamesystem.h"

-#include "physics_saverestore.h"

-#include "vcollide_parse.h"

-#include "positionwatcher.h"

-#include "fmtstr.h"

-#include "physics_prop_ragdoll.h"

-

-#define HINGE_NOTIFY HL2_EPISODIC

-#if HINGE_NOTIFY

-#include "physconstraint_sounds.h"

-#endif

-

-#include "physconstraint.h"

-

-// memdbgon must be the last include file in a .cpp file!!!

-#include "tier0/memdbgon.h"

-

-#define SF_CONSTRAINT_DISABLE_COLLISION			0x0001

-#define SF_SLIDE_LIMIT_ENDS						0x0002

-#define SF_PULLEY_RIGID							0x0002

-#define SF_LENGTH_RIGID							0x0002

-#define SF_RAGDOLL_FREEMOVEMENT					0x0002

-#define SF_CONSTRAINT_START_INACTIVE			0x0004

-#define SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY		0x0008

-#define SF_CONSTRAINT_NO_CONNECT_UNTIL_ACTIVATED	0x0010	// Will only check the two attached entities at activation

-

-

-ConVar    g_debug_constraint_sounds	  ( "g_debug_constraint_sounds", "0", FCVAR_CHEAT, "Enable debug printing about constraint sounds.");

-

-struct constraint_anchor_t

-{

-	Vector		localOrigin;

-	EHANDLE		hEntity;

-	int			parentAttachment;

-	string_t	name;

-	float		massScale;

-};

-

-class CAnchorList : public CAutoGameSystem

-{

-public:

-	CAnchorList( char const *name ) : CAutoGameSystem( name )

-	{

-	}

-	void LevelShutdownPostEntity() 

-	{

-		m_list.Purge();

-	}

-

-	void AddToList( CBaseEntity *pEntity, float massScale )

-	{

-		int index = m_list.AddToTail();

-		constraint_anchor_t *pAnchor = &m_list[index];

-

-		pAnchor->hEntity = pEntity->GetParent();

-		pAnchor->parentAttachment = pEntity->GetParentAttachment();

-		pAnchor->name = pEntity->GetEntityName();

-		pAnchor->localOrigin = pEntity->GetLocalOrigin();

-		pAnchor->massScale = massScale;

-	}

-

-	constraint_anchor_t *Find( string_t name )

-	{

-		for ( int i = m_list.Count()-1; i >=0; i-- )

-		{

-			if ( FStrEq( STRING(m_list[i].name), STRING(name) ) )

-			{

-				return &m_list[i];

-			}

-		}

-		return NULL;

-	}

-

-private:

-	CUtlVector<constraint_anchor_t>	m_list;

-};

-

-static CAnchorList g_AnchorList( "CAnchorList" );

-

-class CConstraintAnchor : public CPointEntity

-{

-	DECLARE_CLASS( CConstraintAnchor, CPointEntity );

-public:

-	CConstraintAnchor()

-	{

-		m_massScale = 1.0f;

-	}

-	void Spawn( void )

-	{

-		if ( GetParent() )

-		{

-			g_AnchorList.AddToList( this, m_massScale );

-			UTIL_Remove( this );

-		}

-	}

-	DECLARE_DATADESC();

-

-	float m_massScale;

-};

-

-BEGIN_DATADESC( CConstraintAnchor )

-	DEFINE_KEYFIELD( m_massScale, FIELD_FLOAT, "massScale" ),

-END_DATADESC()

-

-LINK_ENTITY_TO_CLASS( info_constraint_anchor, CConstraintAnchor );

-

-class CPhysConstraintSystem : public CLogicalEntity

-{

-	DECLARE_CLASS( CPhysConstraintSystem, CLogicalEntity );

-public:

-

-	void Spawn();

-	IPhysicsConstraintGroup *GetVPhysicsGroup() { return m_pMachine; }

-

-	DECLARE_DATADESC();

-private:

-	IPhysicsConstraintGroup *m_pMachine;

-	int						m_additionalIterations;

-};

-

-BEGIN_DATADESC( CPhysConstraintSystem )

-	DEFINE_PHYSPTR( m_pMachine ),

-	DEFINE_KEYFIELD( m_additionalIterations, FIELD_INTEGER, "additionaliterations" ),

-	

-END_DATADESC()

-

-

-void CPhysConstraintSystem::Spawn()

-{

-	constraint_groupparams_t group;

-	group.Defaults();

-	group.additionalIterations = m_additionalIterations;

-	m_pMachine = physenv->CreateConstraintGroup( group );

-}

-

-LINK_ENTITY_TO_CLASS( phys_constraintsystem, CPhysConstraintSystem );

-

-void PhysTeleportConstrainedEntity( CBaseEntity *pTeleportSource, IPhysicsObject *pObject0, IPhysicsObject *pObject1, const Vector &prevPosition, const QAngle &prevAngles, bool physicsRotate )

-{

-	// teleport the other object

-	CBaseEntity *pEntity0 = static_cast<CBaseEntity *> (pObject0->GetGameData());

-	CBaseEntity *pEntity1 = static_cast<CBaseEntity *> (pObject1->GetGameData());

-	if ( !pEntity0 || !pEntity1 )

-		return;

-

-	// figure out which entity needs to be fixed up (the one that isn't pTeleportSource)

-	CBaseEntity *pFixup = pEntity1;

-	// teleport the other object

-	if ( pTeleportSource != pEntity0 )

-	{

-		if ( pTeleportSource != pEntity1 )

-		{

-			Msg("Bogus teleport notification!!\n");

-			return;

-		}

-		pFixup = pEntity0;

-	}

-

-	// constraint doesn't move this entity

-	if ( pFixup->GetMoveType() != MOVETYPE_VPHYSICS )

-		return;

-

-	if ( !pFixup->VPhysicsGetObject() || !pFixup->VPhysicsGetObject()->IsMoveable() )

-		return;

-

-	QAngle oldAngles = prevAngles;

-

-	if ( !physicsRotate )

-	{

-		oldAngles = pTeleportSource->GetAbsAngles();

-	}

-

-	matrix3x4_t startCoord, startInv, endCoord, xform;

-	AngleMatrix( oldAngles, prevPosition, startCoord );

-	MatrixInvert( startCoord, startInv );

-	ConcatTransforms( pTeleportSource->EntityToWorldTransform(), startInv, xform );

-	QAngle fixupAngles;

-	Vector fixupPos;

-

-	ConcatTransforms( xform, pFixup->EntityToWorldTransform(), endCoord );

-	MatrixAngles( endCoord, fixupAngles, fixupPos );

-	pFixup->Teleport( &fixupPos, &fixupAngles, NULL );

-}

-

-static void DrawPhysicsBounds( IPhysicsObject *pObject, int r, int g, int b, int a )

-{

-	const CPhysCollide *pCollide = pObject->GetCollide();

-	Vector pos;

-	QAngle angles;

-	pObject->GetPosition( &pos, &angles );

-	Vector mins, maxs;

-	physcollision->CollideGetAABB( &mins, &maxs, pCollide, vec3_origin, vec3_angle );

-	// don't fight the z-buffer

-	mins -= Vector(1,1,1);

-	maxs += Vector(1,1,1);

-	NDebugOverlay::BoxAngles( pos, mins, maxs, angles, r, g, b, a, 0 );

-}

-

-static void DrawConstraintObjectsAxes(CBaseEntity *pConstraintEntity, IPhysicsConstraint *pConstraint)

-{

-	if ( !pConstraint || !pConstraintEntity )

-		return;

-	matrix3x4_t xformRef, xformAtt;

-	bool bXform = pConstraint->GetConstraintTransform( &xformRef, &xformAtt );

-	IPhysicsObject *pRef = pConstraint->GetReferenceObject();

-

-	if ( pRef && !pRef->IsStatic() )

-	{

-		if ( bXform )

-		{

-			Vector pos, posWorld;

-			QAngle angles;

-			MatrixAngles( xformRef, angles, pos );

-			pRef->LocalToWorld( &posWorld, pos );

-			NDebugOverlay::Axis( posWorld, vec3_angle, 12, false, 0 );

-		}

-		DrawPhysicsBounds( pRef, 0, 255, 0, 12 );

-	}

-	IPhysicsObject *pAttach = pConstraint->GetAttachedObject();

-	if ( pAttach && !pAttach->IsStatic() )

-	{

-		if ( bXform )

-		{

-			Vector pos, posWorld;

-			QAngle angles;

-			MatrixAngles( xformAtt, angles, pos );

-			pAttach->LocalToWorld( &posWorld, pos );

-			NDebugOverlay::Axis( posWorld, vec3_angle, 12, false, 0 );

-		}

-		DrawPhysicsBounds( pAttach, 255, 0, 0, 12 );

-	}

-}

-

-void CPhysConstraint::ClearStaticFlag( IPhysicsObject *pObj )

-{

-	if ( !pObj )

-		return;

-	PhysClearGameFlags( pObj, FVPHYSICS_CONSTRAINT_STATIC );

-}

-

-void CPhysConstraint::Deactivate()

-{

-	if ( !m_pConstraint )

-		return;

-	m_pConstraint->Deactivate();

-	ClearStaticFlag( m_pConstraint->GetReferenceObject() );

-	ClearStaticFlag( m_pConstraint->GetAttachedObject() );

-	if ( m_spawnflags & SF_CONSTRAINT_DISABLE_COLLISION )

-	{

-		// constraint may be getting deactivated because an object got deleted, so check them here.

-		IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();

-		IPhysicsObject *pAtt = m_pConstraint->GetAttachedObject();

-		if ( pRef && pAtt )

-		{

-			PhysEnableEntityCollisions( pRef, pAtt );

-		}

-	}

-}

-

-void CPhysConstraint::OnBreak( void )

-{

-	Deactivate();

-	if ( m_breakSound != NULL_STRING )

-	{

-		CPASAttenuationFilter filter( this, ATTN_STATIC );

-

-		Vector origin = GetAbsOrigin();

-		Vector refPos = origin, attachPos = origin;

-

-		IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();

-		if ( pRef && (pRef != g_PhysWorldObject) )

-		{

-			pRef->GetPosition( &refPos, NULL );

-			attachPos = refPos;

-		}

-		IPhysicsObject *pAttach = m_pConstraint->GetAttachedObject();

-		if ( pAttach && (pAttach != g_PhysWorldObject) )

-		{

-			pAttach->GetPosition( &attachPos, NULL );

-			if ( !pRef || (pRef == g_PhysWorldObject) )

-			{

-				refPos = attachPos;

-			}

-		}

-		

-		VectorAdd( refPos, attachPos, origin );

-		origin *= 0.5f;

-

-		EmitSound_t ep;

-		ep.m_nChannel = CHAN_STATIC;

-		ep.m_pSoundName = STRING(m_breakSound);

-		ep.m_flVolume = VOL_NORM;

-		ep.m_SoundLevel = ATTN_TO_SNDLVL( ATTN_STATIC );

-		ep.m_pOrigin = &origin;

-

-		EmitSound( filter, entindex(), ep );

-	}

-	m_OnBreak.FireOutput( this, this );

-	// queue this up to be deleted at the end of physics 

-	// The Deactivate() call should make sure we don't get more of these callbacks.

-	PhysCallbackRemove( this->NetworkProp() );

-}

-

-void CPhysConstraint::InputBreak( inputdata_t &inputdata )

-{

-	if ( m_pConstraint ) 

-		m_pConstraint->Deactivate();

-	

-	OnBreak();

-}

-

-void CPhysConstraint::InputOnBreak( inputdata_t &inputdata )

-{

-	OnBreak();

-}

-

-void CPhysConstraint::InputTurnOn( inputdata_t &inputdata )

-{

-	if ( HasSpawnFlags( SF_CONSTRAINT_NO_CONNECT_UNTIL_ACTIVATED ) )

-	{

-		ActivateConstraint();

-	}

-

-	if ( !m_pConstraint || !m_pConstraint->GetReferenceObject() || !m_pConstraint->GetAttachedObject() )

-		return;

-

-	m_pConstraint->Activate();

-	m_pConstraint->GetReferenceObject()->Wake();

-	m_pConstraint->GetAttachedObject()->Wake();

-}

-

-void CPhysConstraint::InputTurnOff( inputdata_t &inputdata )

-{

-	Deactivate();

-}

-

-int CPhysConstraint::DrawDebugTextOverlays()

-{

-	int pos = BaseClass::DrawDebugTextOverlays();

-	if ( m_pConstraint && (m_debugOverlays & OVERLAY_TEXT_BIT) )

-	{

-		constraint_breakableparams_t params;

-		Q_memset(&params,0,sizeof(params));

-		m_pConstraint->GetConstraintParams( &params );

-		

-		if ( (params.bodyMassScale[0] != 1.0f && params.bodyMassScale[0] != 0.0f) || (params.bodyMassScale[1] != 1.0f && params.bodyMassScale[1] != 0.0f) )

-		{

-			CFmtStr str("mass ratio %.4f:%.4f\n", params.bodyMassScale[0], params.bodyMassScale[1] );

-			NDebugOverlay::EntityTextAtPosition( GetAbsOrigin(), pos, str.Access(), 0, 255, 255, 0, 255 );

-		}

-		pos++;

-	}

-	return pos;

-}

-

-void CPhysConstraint::DrawDebugGeometryOverlays()

-{

-	if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )

-	{

-		DrawConstraintObjectsAxes(this, m_pConstraint);

-	}

-	BaseClass::DrawDebugGeometryOverlays();

-}

-

-void CPhysConstraint::GetBreakParams( constraint_breakableparams_t &params, const hl_constraint_info_t &info )

-{

-	params.Defaults();

-	params.forceLimit = lbs2kg(m_forceLimit);

-	params.torqueLimit = lbs2kg(m_torqueLimit);

-	params.isActive = HasSpawnFlags( SF_CONSTRAINT_START_INACTIVE ) ? false : true;

-	params.bodyMassScale[0] = info.massScale[0];

-	params.bodyMassScale[1] = info.massScale[1];

-}

-

-BEGIN_DATADESC( CPhysConstraint )

-

-	DEFINE_PHYSPTR( m_pConstraint ),

-

-	DEFINE_KEYFIELD( m_nameSystem, FIELD_STRING, "constraintsystem" ),

-	DEFINE_KEYFIELD( m_nameAttach1, FIELD_STRING, "attach1" ),

-	DEFINE_KEYFIELD( m_nameAttach2, FIELD_STRING, "attach2" ),

-	DEFINE_KEYFIELD( m_breakSound, FIELD_SOUNDNAME, "breaksound" ),

-	DEFINE_KEYFIELD( m_forceLimit, FIELD_FLOAT, "forcelimit" ),

-	DEFINE_KEYFIELD( m_torqueLimit, FIELD_FLOAT, "torquelimit" ),

-	DEFINE_KEYFIELD( m_minTeleportDistance, FIELD_FLOAT, "teleportfollowdistance" ),

-//	DEFINE_FIELD( m_teleportTick, FIELD_INTEGER ),

-

-	DEFINE_OUTPUT( m_OnBreak, "OnBreak" ),

-

-	DEFINE_INPUTFUNC( FIELD_VOID, "Break", InputBreak ),

-	DEFINE_INPUTFUNC( FIELD_VOID, "ConstraintBroken", InputOnBreak ),

-

-	DEFINE_INPUTFUNC( FIELD_VOID, "TurnOn", InputTurnOn ),

-	DEFINE_INPUTFUNC( FIELD_VOID, "TurnOff", InputTurnOff ),

-

-END_DATADESC()

-

-

-CPhysConstraint::CPhysConstraint( void )

-{

-	m_pConstraint = NULL;

-	m_nameAttach1 = NULL_STRING;

-	m_nameAttach2 = NULL_STRING;

-	m_forceLimit = 0;

-	m_torqueLimit = 0;

-	m_teleportTick = 0xFFFFFFFF;

-	m_minTeleportDistance = 0.0f;

-}

-

-CPhysConstraint::~CPhysConstraint()

-{

-	Deactivate();

-	physenv->DestroyConstraint( m_pConstraint );

-}

-

-void CPhysConstraint::Precache( void )

-{

-	if ( m_breakSound != NULL_STRING )

-	{

-		PrecacheScriptSound( STRING(m_breakSound) );

-	}

-}

-

-void CPhysConstraint::Spawn( void )

-{

-	BaseClass::Spawn();

-

-	Precache();

-}

-

-// debug function - slow, uses dynamic_cast<> - use this to query the attached objects

-// physics_debug_entity toggles the constraint system for an object using this

-bool GetConstraintAttachments( CBaseEntity *pEntity, CBaseEntity *pAttachOut[2], IPhysicsObject *pAttachVPhysics[2] )

-{

-	CPhysConstraint *pConstraintEntity = dynamic_cast<CPhysConstraint *>(pEntity);

-	if ( pConstraintEntity )

-	{

-		IPhysicsConstraint *pConstraint = pConstraintEntity->GetPhysConstraint();

-		if ( pConstraint )

-		{

-			IPhysicsObject *pRef = pConstraint->GetReferenceObject();

-			pAttachVPhysics[0] = pRef;

-			pAttachOut[0] = pRef ? static_cast<CBaseEntity *>(pRef->GetGameData()) : NULL;

-			IPhysicsObject *pAttach = pConstraint->GetAttachedObject();

-			pAttachVPhysics[1] = pAttach;

-			pAttachOut[1] = pAttach ? static_cast<CBaseEntity *>(pAttach->GetGameData()) : NULL;

-			return true;

-		}

-	}

-	return false;

-}

-

-void DebugConstraint(CBaseEntity *pEntity)

-{

-	CPhysConstraint *pConstraintEntity = dynamic_cast<CPhysConstraint *>(pEntity);

-	if ( pConstraintEntity )

-	{

-		IPhysicsConstraint *pConstraint = pConstraintEntity->GetPhysConstraint();

-		if ( pConstraint )

-		{

-			pConstraint->OutputDebugInfo();

-		}

-	}

-}

-

-

-void FindPhysicsAnchor( string_t name, hl_constraint_info_t &info, int index, CBaseEntity *pErrorEntity )

-{

-	constraint_anchor_t *pAnchor = g_AnchorList.Find( name );

-	if ( pAnchor )

-	{

-		CBaseEntity *pEntity = pAnchor->hEntity;

-		if ( pEntity )

-		{

-			info.massScale[index] = pAnchor->massScale;

-			bool bWroteAttachment = false;

-			if ( pAnchor->parentAttachment > 0 )

-			{

-				CBaseAnimating *pAnim = pAnchor->hEntity->GetBaseAnimating();

-				if ( pAnim )

-				{

-					IPhysicsObject *list[VPHYSICS_MAX_OBJECT_LIST_COUNT];

-					int listCount = pAnchor->hEntity->VPhysicsGetObjectList( list, ARRAYSIZE(list) );

-					int iPhysicsBone = pAnim->GetPhysicsBone( pAnim->GetAttachmentBone( pAnchor->parentAttachment ) );

-					if ( iPhysicsBone < listCount )

-					{

-						Vector pos;

-						info.pObjects[index] = list[iPhysicsBone];

-						pAnim->GetAttachment( pAnchor->parentAttachment, pos );

-						list[iPhysicsBone]->WorldToLocal( &info.anchorPosition[index], pos );

-						bWroteAttachment = true;

-					}

-				}

-			}

-			if ( !bWroteAttachment )

-			{

-				info.anchorPosition[index] = pAnchor->localOrigin;

-				info.pObjects[index] = pAnchor->hEntity->VPhysicsGetObject();

-			}

-		}

-		else

-		{

-			pAnchor = NULL;

-		}

-	}

-	if ( !pAnchor )

-	{

-		info.anchorPosition[index] = vec3_origin;

-		info.pObjects[index] = FindPhysicsObjectByName( STRING(name), pErrorEntity );

-		info.massScale[index] = 1.0f;

-	}

-}

-

-void CPhysConstraint::OnConstraintSetup( hl_constraint_info_t &info )

-{

-	if ( info.pObjects[0] && info.pObjects[1] )

-	{

-		SetupTeleportationHandling( info );

-	}

-	if ( m_spawnflags & SF_CONSTRAINT_DISABLE_COLLISION )

-	{

-		PhysDisableEntityCollisions( info.pObjects[0], info.pObjects[1] );

-	}

-}

-

-void CPhysConstraint::SetupTeleportationHandling( hl_constraint_info_t &info )

-{

-	CBaseEntity *pEntity0 = (CBaseEntity *)info.pObjects[0]->GetGameData();

-	if ( pEntity0 )

-	{

-		g_pNotify->AddEntity( this, pEntity0 );

-	}

-

-	CBaseEntity *pEntity1 = (CBaseEntity *)info.pObjects[1]->GetGameData();

-	if ( pEntity1 )

-	{

-		g_pNotify->AddEntity( this, pEntity1 );

-	}

-}

-

-static IPhysicsConstraintGroup *GetRagdollConstraintGroup( IPhysicsObject *pObj )

-{

-	if ( pObj )

-	{

-		CBaseEntity *pEntity = static_cast<CBaseEntity *>(pObj->GetGameData());

-		ragdoll_t *pRagdoll = Ragdoll_GetRagdoll(pEntity);

-		if ( pRagdoll )

-			return pRagdoll->pGroup;

-	}

-	return NULL;

-}

-

-void CPhysConstraint::GetConstraintObjects( hl_constraint_info_t &info )

-{

-	FindPhysicsAnchor( m_nameAttach1, info, 0, this );

-	FindPhysicsAnchor( m_nameAttach2, info, 1, this );

-

-	// Missing one object, assume the world instead

-	if ( info.pObjects[0] == NULL && info.pObjects[1] )

-	{

-		if ( Q_strlen(STRING(m_nameAttach1)) )

-		{

-			Warning("Bogus constraint %s (attaches ENTITY NOT FOUND:%s to %s)\n", GetDebugName(), STRING(m_nameAttach1), STRING(m_nameAttach2));

-#ifdef HL2_EPISODIC

-			info.pObjects[0] = info.pObjects[1] = NULL;

-			return;

-#endif	// HL2_EPISODIC

-		}

-		info.pObjects[0] = g_PhysWorldObject;

-		info.massScale[0] = info.massScale[1] = 1.0f; // no mass scale on world constraint

-	}

-	else if ( info.pObjects[0] && !info.pObjects[1] )

-	{

-		if ( Q_strlen(STRING(m_nameAttach2)) )

-		{

-			Warning("Bogus constraint %s (attaches %s to ENTITY NOT FOUND:%s)\n", GetDebugName(), STRING(m_nameAttach1), STRING(m_nameAttach2));

-#ifdef HL2_EPISODIC

-			info.pObjects[0] = info.pObjects[1] = NULL;

-			return;

-#endif	// HL2_EPISODIC

-		}

-		info.pObjects[1] = info.pObjects[0];

-		info.pObjects[0] = g_PhysWorldObject;		// Try to make the world object consistently object0 for ease of implementation

-		info.massScale[0] = info.massScale[1] = 1.0f; // no mass scale on world constraint

-		info.swapped = true;

-	}

-

-	info.pGroup = GetRagdollConstraintGroup(info.pObjects[0]);

-	if ( !info.pGroup )

-	{

-		info.pGroup = GetRagdollConstraintGroup(info.pObjects[1]);

-	}

-}

-

-void CPhysConstraint::Activate( void )

-{

-	BaseClass::Activate();

-

-	if ( HasSpawnFlags( SF_CONSTRAINT_NO_CONNECT_UNTIL_ACTIVATED ) == false )

-	{

-		if ( !ActivateConstraint() )

-		{

-			UTIL_Remove(this);

-		}

-	}

-}

-

-IPhysicsConstraintGroup *GetConstraintGroup( string_t systemName )

-{

-	CBaseEntity *pMachine = gEntList.FindEntityByName( NULL, systemName );

-

-	if ( pMachine )

-	{

-		CPhysConstraintSystem *pGroup = dynamic_cast<CPhysConstraintSystem *>(pMachine);

-		if ( pGroup )

-		{

-			return pGroup->GetVPhysicsGroup();

-		}

-	}

-	return NULL;

-}

-

-bool CPhysConstraint::ActivateConstraint( void )

-{

-	// A constraint attaches two objects to each other.

-	// The constraint is specified in the coordinate frame of the "reference" object

-	// and constrains the "attached" object

-	hl_constraint_info_t info;

-	if ( m_pConstraint )

-	{

-		// already have a constraint, don't make a new one

-		info.pObjects[0] = m_pConstraint->GetReferenceObject();

-		info.pObjects[1] = m_pConstraint->GetAttachedObject();

-		OnConstraintSetup(info);

-		return true;

-	}

-

-	GetConstraintObjects( info );

-	if ( !info.pObjects[0] && !info.pObjects[1] )

-		return false;

-

-	if ( info.pObjects[0]->IsStatic() && info.pObjects[1]->IsStatic() )

-	{

-		Warning("Constraint (%s) attached to two static objects (%s and %s)!!!\n", STRING(GetEntityName()), STRING(m_nameAttach1), m_nameAttach2 == NULL_STRING ? "world" : STRING(m_nameAttach2) );

-		return false;

-	}

-

-	if ( info.pObjects[0]->GetShadowController() && info.pObjects[1]->GetShadowController() )

-	{

-		Warning("Constraint (%s) attached to two shadow objects (%s and %s)!!!\n", STRING(GetEntityName()), STRING(m_nameAttach1), m_nameAttach2 == NULL_STRING ? "world" : STRING(m_nameAttach2) );

-		return false;

-	}

-	IPhysicsConstraintGroup *pGroup = GetConstraintGroup( m_nameSystem );

-	if ( !pGroup )

-	{

-		pGroup = info.pGroup;

-	}

-	m_pConstraint = CreateConstraint( pGroup, info );

-	if ( !m_pConstraint )

-		return false;

-

-	m_pConstraint->SetGameData( (void *)this );

-

-	if ( pGroup )

-	{

-		pGroup->Activate();

-	}

-

-	OnConstraintSetup(info);

-

-	return true;

-}

-

-void CPhysConstraint::NotifySystemEvent( CBaseEntity *pNotify, notify_system_event_t eventType, const notify_system_event_params_t &params )

-{

-	// don't recurse

-	if ( eventType != NOTIFY_EVENT_TELEPORT || (unsigned int)gpGlobals->tickcount == m_teleportTick )

-		return;

-

-	float distance = (params.pTeleport->prevOrigin - pNotify->GetAbsOrigin()).Length();

-	

-	// no need to follow a small teleport

-	if ( distance <= m_minTeleportDistance )

-		return;

-

-	m_teleportTick = gpGlobals->tickcount;

-

-	PhysTeleportConstrainedEntity( pNotify, m_pConstraint->GetReferenceObject(), m_pConstraint->GetAttachedObject(), params.pTeleport->prevOrigin, params.pTeleport->prevAngles, params.pTeleport->physicsRotate );

-}

-

-class CPhysHinge : public CPhysConstraint, public IVPhysicsWatcher

-{

-	DECLARE_CLASS( CPhysHinge, CPhysConstraint );

-

-public:

-	void Spawn( void );

-	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-	{

-		if ( m_hinge.worldAxisDirection == vec3_origin )

-		{

-			DevMsg("ERROR: Hinge with bad data!!!\n" );

-			return NULL;

-		}

-		GetBreakParams( m_hinge.constraint, info );

-		m_hinge.constraint.strength = 1.0;

-		// BUGBUG: These numbers are very hard to edit

-		// Scale by 1000 to make things easier

-		// CONSIDER: Unify the units of torque around something other 

-		// than HL units (kg * in^2 / s ^2)

-		m_hinge.hingeAxis.SetAxisFriction( 0, 0, m_hingeFriction * 1000 );

-

-		int hingeAxis;

-		if ( IsWorldHinge( info, &hingeAxis ) )

-		{

-			info.pObjects[1]->BecomeHinged( hingeAxis );

-		}

-		else

-		{

-			RemoveSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY );

-		}

-

-		return physenv->CreateHingeConstraint( info.pObjects[0], info.pObjects[1], pGroup, m_hinge );

-	}

-

-	void DrawDebugGeometryOverlays()

-	{

-		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )

-		{

-			NDebugOverlay::Line(m_hinge.worldPosition, m_hinge.worldPosition + 48 * m_hinge.worldAxisDirection, 0, 255, 0, false, 0 );

-		}

-		BaseClass::DrawDebugGeometryOverlays();

-	}

-

-	void InputSetVelocity( inputdata_t &inputdata )

-	{

-		if ( !m_pConstraint || !m_pConstraint->GetReferenceObject() || !m_pConstraint->GetAttachedObject() )

-			return;

-	

-		float speed = inputdata.value.Float();

-		float massLoad = 1;

-		int numMasses = 0;

-		if ( m_pConstraint->GetReferenceObject()->IsMoveable() )

-		{

-			massLoad = m_pConstraint->GetReferenceObject()->GetInertia().Length();

-			numMasses++;

-			m_pConstraint->GetReferenceObject()->Wake();

-		}

-		if ( m_pConstraint->GetAttachedObject()->IsMoveable() )

-		{

-			massLoad += m_pConstraint->GetAttachedObject()->GetInertia().Length();

-			numMasses++;

-			m_pConstraint->GetAttachedObject()->Wake();

-		}

-		if ( numMasses > 0 )

-		{

-			massLoad /= (float)numMasses;

-		}

-		

-		float loadscale = m_systemLoadScale != 0 ? m_systemLoadScale : 1;

-		m_pConstraint->SetAngularMotor( speed, speed * loadscale * massLoad * loadscale * (1.0/TICK_INTERVAL) );

-	}

-

-	void InputSetHingeFriction( inputdata_t &inputdata )

-	{

-		m_hingeFriction = inputdata.value.Float();

-		Msg("Setting hinge friction to %f\n", m_hingeFriction );

-		m_hinge.hingeAxis.SetAxisFriction( 0, 0, m_hingeFriction * 1000 );

-	}

-

-	virtual void Deactivate()

-	{

-		if ( HasSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY ) )

-		{

-			if ( m_pConstraint && m_pConstraint->GetAttachedObject() )

-			{

-				// NOTE: RemoveHinged() is always safe

-				m_pConstraint->GetAttachedObject()->RemoveHinged();

-			}

-		}

-

-		BaseClass::Deactivate();

-	}

-	

-	void NotifyVPhysicsStateChanged( IPhysicsObject *pPhysics, CBaseEntity *pEntity, bool bAwake )

-	{

-#if HINGE_NOTIFY

-		Assert(m_pConstraint);

-		if (!m_pConstraint) 

-			return;

-

-		// if something woke up, start thinking. If everything is asleep, stop thinking.

-		if ( bAwake )

-		{

-			// Did something wake up when I was not thinking?

-			if ( GetNextThink() == TICK_NEVER_THINK )

-			{

-				m_soundInfo.StartThinking(this, 

-					VelocitySampler::GetRelativeAngularVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()) ,

-					m_hinge.worldAxisDirection

-					);

-

-				SetThink(&CPhysHinge::SoundThink);

-				SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());

-			}

-		}

-		else

-		{

-			// Is everything asleep? If so, stop thinking.

-			if ( GetNextThink() != TICK_NEVER_THINK				&&

-				m_pConstraint->GetAttachedObject()->IsAsleep() &&

-				m_pConstraint->GetReferenceObject()->IsAsleep() )

-			{

-				m_soundInfo.StopThinking(this);

-				SetNextThink(TICK_NEVER_THINK);

-			}

-		}

-#endif

-	}

-

-

-#if HINGE_NOTIFY

-	virtual void OnConstraintSetup( hl_constraint_info_t &info )

-	{

-		CBaseEntity *pEntity0 = info.pObjects[0] ? static_cast<CBaseEntity *>(info.pObjects[0]->GetGameData()) : NULL;

-		if ( pEntity0 && !info.pObjects[0]->IsStatic()  )

-		{

-			WatchVPhysicsStateChanges( this, pEntity0 );

-		}

-		CBaseEntity *pEntity1 = info.pObjects[1] ? static_cast<CBaseEntity *>(info.pObjects[1]->GetGameData()) : NULL;

-		if ( pEntity1 && !info.pObjects[1]->IsStatic()  )

-		{

-			WatchVPhysicsStateChanges( this, pEntity1 );

-		}

-		BaseClass::OnConstraintSetup(info);

-	}

-

-	void SoundThink( void );

-	// void Spawn( void );

-	void Activate( void );

-	void Precache( void );

-#endif

-

-	DECLARE_DATADESC();

-

-

-#if HINGE_NOTIFY

-protected:

-	ConstraintSoundInfo m_soundInfo;

-#endif

-

-private:

-	constraint_hingeparams_t m_hinge;

-	float m_hingeFriction;

-	float	m_systemLoadScale;

-	bool IsWorldHinge( const hl_constraint_info_t &info, int *pAxisOut );

-};

-

-BEGIN_DATADESC( CPhysHinge )

-

-// Quiet down classcheck

-//	DEFINE_FIELD( m_hinge, FIELD_??? ),

-

-	DEFINE_KEYFIELD( m_hingeFriction, FIELD_FLOAT, "hingefriction" ),

-	DEFINE_FIELD( m_hinge.worldPosition, FIELD_POSITION_VECTOR ),

-	DEFINE_KEYFIELD( m_hinge.worldAxisDirection, FIELD_VECTOR, "hingeaxis" ),

-	DEFINE_KEYFIELD( m_systemLoadScale, FIELD_FLOAT, "systemloadscale" ),

-	DEFINE_INPUTFUNC( FIELD_FLOAT, "SetAngularVelocity", InputSetVelocity ),

-	DEFINE_INPUTFUNC( FIELD_FLOAT, "SetHingeFriction", InputSetHingeFriction ),

-

-#if HINGE_NOTIFY

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_THRESHOLD] , FIELD_FLOAT, "minSoundThreshold" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_FULL] , FIELD_FLOAT, "maxSoundThreshold" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundFwd, FIELD_SOUNDNAME, "slidesoundfwd" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundBack, FIELD_SOUNDNAME, "slidesoundback" ),

-

-	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[0], FIELD_SOUNDNAME, "reversalsoundSmall" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[1], FIELD_SOUNDNAME, "reversalsoundMedium" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[2], FIELD_SOUNDNAME, "reversalsoundLarge" ),

-

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[0] , FIELD_FLOAT, "reversalsoundthresholdSmall" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[1], FIELD_FLOAT, "reversalsoundthresholdMedium" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[2] , FIELD_FLOAT, "reversalsoundthresholdLarge" ),

-

-	DEFINE_THINKFUNC( SoundThink ),

-#endif

-

-END_DATADESC()

-

-

-LINK_ENTITY_TO_CLASS( phys_hinge, CPhysHinge );

-

-

-void CPhysHinge::Spawn( void )

-{

-	m_hinge.worldPosition = GetLocalOrigin();

-	m_hinge.worldAxisDirection -= GetLocalOrigin();

-	VectorNormalize(m_hinge.worldAxisDirection);

-	UTIL_SnapDirectionToAxis( m_hinge.worldAxisDirection );

-

-	m_hinge.hingeAxis.SetAxisFriction( 0, 0, 0 );

-

-	if ( HasSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY ) )

-	{

-		masscenteroverride_t params;

-		if ( m_nameAttach1 == NULL_STRING )

-		{

-			params.SnapToAxis( m_nameAttach2, m_hinge.worldPosition, m_hinge.worldAxisDirection );

-			PhysSetMassCenterOverride( params );

-		}

-		else if ( m_nameAttach2 == NULL_STRING )

-		{

-			params.SnapToAxis( m_nameAttach1, m_hinge.worldPosition, m_hinge.worldAxisDirection );

-			PhysSetMassCenterOverride( params );

-		}

-		else

-		{

-			RemoveSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY );

-		}

-	}

-

-	Precache();

-}

-

-#if HINGE_NOTIFY

-void CPhysHinge::Activate( void )

-{

-	BaseClass::Activate();

-

-	m_soundInfo.OnActivate(this);

-	if (m_pConstraint)

-	{

-		m_soundInfo.StartThinking(this, 

-			VelocitySampler::GetRelativeAngularVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()) ,

-			m_hinge.worldAxisDirection

-			);

-

-		SetThink(&CPhysHinge::SoundThink);

-		SetNextThink( gpGlobals->curtime + m_soundInfo.getThinkRate() );

-	}

-}

-

-void CPhysHinge::Precache( void )

-{

-	BaseClass::Precache();

-	return m_soundInfo.OnPrecache(this);

-}

-

-#endif

-

-

-static int GetUnitAxisIndex( const Vector &axis )

-{

-	bool valid = false;

-	int index = -1;

-

-	for ( int i = 0; i < 3; i++ )

-	{

-		if ( axis[i] != 0 )

-		{

-			if ( fabs(axis[i]) == 1 )

-			{

-				if ( index  < 0 )

-				{

-					index = i;

-					valid = true;

-					continue;

-				}

-			}

-			valid = false;

-		}

-	}

-	return valid ? index : -1;

-}

-

-bool CPhysHinge::IsWorldHinge( const hl_constraint_info_t &info, int *pAxisOut )

-{

-	if ( HasSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY ) && info.pObjects[0] == g_PhysWorldObject )

-	{

-		Vector localHinge;

-		info.pObjects[1]->WorldToLocalVector( &localHinge, m_hinge.worldAxisDirection );

-		UTIL_SnapDirectionToAxis( localHinge );

-		int hingeAxis = GetUnitAxisIndex( localHinge );

-		if ( hingeAxis >= 0 )

-		{

-			*pAxisOut = hingeAxis;

-			return true;

-		}

-	}

-	return false;

-}

-

-

-#if HINGE_NOTIFY

-void CPhysHinge::SoundThink( void )

-{

-	Assert(m_pConstraint);

-	if (!m_pConstraint)

-		return;

-

-	IPhysicsObject * pAttached = m_pConstraint->GetAttachedObject(), *pReference = m_pConstraint->GetReferenceObject();

-	Assert( pAttached && pReference );

-	if (pAttached && pReference)

-	{

-		Vector relativeVel = VelocitySampler::GetRelativeAngularVelocity(pAttached,pReference);

-		if (g_debug_constraint_sounds.GetBool())

-		{

-			NDebugOverlay::Line( GetAbsOrigin(), GetAbsOrigin() + (relativeVel), 255, 255, 0, true, 0.1f );

-		}

-		m_soundInfo.OnThink( this, relativeVel );

-

-		SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());

-	}

-}

-#endif

-

-class CPhysBallSocket : public CPhysConstraint

-{

-public:

-	DECLARE_CLASS( CPhysBallSocket, CPhysConstraint );

-

-	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-	{

-		constraint_ballsocketparams_t ballsocket;

-	

-		ballsocket.Defaults();

-		

-		for ( int i = 0; i < 2; i++ )

-		{

-			info.pObjects[i]->WorldToLocal( &ballsocket.constraintPosition[i], GetAbsOrigin() );

-		}

-		GetBreakParams( ballsocket.constraint, info );

-		ballsocket.constraint.torqueLimit = 0;

-

-		return physenv->CreateBallsocketConstraint( info.pObjects[0], info.pObjects[1], pGroup, ballsocket );

-	}

-};

-

-LINK_ENTITY_TO_CLASS( phys_ballsocket, CPhysBallSocket );

-

-class CPhysSlideConstraint : public CPhysConstraint, public IVPhysicsWatcher

-{

-public:

-	DECLARE_CLASS( CPhysSlideConstraint, CPhysConstraint );

-

-	DECLARE_DATADESC();

-	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );

-	void InputSetVelocity( inputdata_t &inputdata )

-	{

-		if ( !m_pConstraint || !m_pConstraint->GetReferenceObject() || !m_pConstraint->GetAttachedObject() )

-			return;

-

-		float speed = inputdata.value.Float();

-		float massLoad = 1;

-		int numMasses = 0;

-		if ( m_pConstraint->GetReferenceObject()->IsMoveable() )

-		{

-			massLoad = m_pConstraint->GetReferenceObject()->GetMass();

-			numMasses++;

-			m_pConstraint->GetReferenceObject()->Wake();

-		}

-		if ( m_pConstraint->GetAttachedObject()->IsMoveable() )

-		{

-			massLoad += m_pConstraint->GetAttachedObject()->GetMass();

-			numMasses++;

-			m_pConstraint->GetAttachedObject()->Wake();

-		}

-		if ( numMasses > 0 )

-		{

-			massLoad /= (float)numMasses;

-		}

-		float loadscale = m_systemLoadScale != 0 ? m_systemLoadScale : 1;

-		m_pConstraint->SetLinearMotor( speed, speed * loadscale * massLoad * (1.0/TICK_INTERVAL) );

-	}

-

-	void DrawDebugGeometryOverlays()

-	{

-		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )

-		{

-			NDebugOverlay::Box( GetAbsOrigin(), -Vector(8,8,8), Vector(8,8,8), 0, 255, 0, 0, 0 );

-			NDebugOverlay::Box( m_axisEnd, -Vector(4,4,4), Vector(4,4,4), 0, 0, 255, 0, 0 );

-			NDebugOverlay::Line( GetAbsOrigin(), m_axisEnd, 255, 255, 0, false, 0 );

-		}

-		BaseClass::DrawDebugGeometryOverlays();

-	}

-

-	void NotifyVPhysicsStateChanged( IPhysicsObject *pPhysics, CBaseEntity *pEntity, bool bAwake )

-	{

-#if HINGE_NOTIFY

-		Assert(m_pConstraint);

-		if (!m_pConstraint) 

-			return;

-

-		// if something woke up, start thinking. If everything is asleep, stop thinking.

-		if ( bAwake )

-		{

-			// Did something wake up when I was not thinking?

-			if ( GetNextThink() == TICK_NEVER_THINK )

-			{

-				Vector axisDirection = m_axisEnd - GetAbsOrigin();

-				VectorNormalize( axisDirection );

-				UTIL_SnapDirectionToAxis( axisDirection );

-

-				m_soundInfo.StartThinking(this, 

-					VelocitySampler::GetRelativeVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()),

-					axisDirection

-					);

-				SetThink(&CPhysSlideConstraint::SoundThink);

-				SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());

-			}

-		}

-		else

-		{

-			// Is everything asleep? If so, stop thinking.

-			if ( GetNextThink() != TICK_NEVER_THINK				&&

-				 m_pConstraint->GetAttachedObject()->IsAsleep() &&

-				 m_pConstraint->GetReferenceObject()->IsAsleep() )

-			{

-				m_soundInfo.StopThinking(this);

-				SetNextThink(TICK_NEVER_THINK);

-			}

-		}

-#endif

-	}

-

-

-#if HINGE_NOTIFY

-	virtual void OnConstraintSetup( hl_constraint_info_t &info )

-	{

-		CBaseEntity *pEntity0 = info.pObjects[0] ? static_cast<CBaseEntity *>(info.pObjects[0]->GetGameData()) : NULL;

-		if ( pEntity0 && !info.pObjects[0]->IsStatic()  )

-		{

-			WatchVPhysicsStateChanges( this, pEntity0 );

-		}

-		CBaseEntity *pEntity1 = info.pObjects[1] ? static_cast<CBaseEntity *>(info.pObjects[1]->GetGameData()) : NULL;

-		if ( pEntity1 && !info.pObjects[1]->IsStatic()  )

-		{

-			WatchVPhysicsStateChanges( this, pEntity1 );

-		}

-		BaseClass::OnConstraintSetup(info);

-	}

-

-

-	void SoundThink( void );

-	// void Spawn( void );

-	void Activate( void );

-	void Precache( void );

-#endif

-

-	Vector	m_axisEnd;

-	float	m_slideFriction;

-	float	m_systemLoadScale;

-

-#if HINGE_NOTIFY

-protected:

-	ConstraintSoundInfo m_soundInfo;

-#endif

-};

-

-LINK_ENTITY_TO_CLASS( phys_slideconstraint, CPhysSlideConstraint );

-

-BEGIN_DATADESC( CPhysSlideConstraint )

-

-	DEFINE_KEYFIELD( m_axisEnd, FIELD_POSITION_VECTOR, "slideaxis" ),

-	DEFINE_KEYFIELD( m_slideFriction, FIELD_FLOAT, "slidefriction" ),

-	DEFINE_KEYFIELD( m_systemLoadScale, FIELD_FLOAT, "systemloadscale" ),

-	DEFINE_INPUTFUNC( FIELD_FLOAT, "SetVelocity", InputSetVelocity ),

-#if HINGE_NOTIFY

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_THRESHOLD] , FIELD_FLOAT, "minSoundThreshold" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_FULL] , FIELD_FLOAT, "maxSoundThreshold" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundFwd, FIELD_SOUNDNAME, "slidesoundfwd" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundBack, FIELD_SOUNDNAME, "slidesoundback" ),

-

-	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[0], FIELD_SOUNDNAME, "reversalsoundSmall" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[1], FIELD_SOUNDNAME, "reversalsoundMedium" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[2], FIELD_SOUNDNAME, "reversalsoundLarge" ),

-

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[0] , FIELD_FLOAT, "reversalsoundthresholdSmall" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[1], FIELD_FLOAT, "reversalsoundthresholdMedium" ),

-	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[2] , FIELD_FLOAT, "reversalsoundthresholdLarge" ),

-

-

-	DEFINE_THINKFUNC( SoundThink ),

-#endif

-

-END_DATADESC()

-

-

-

-IPhysicsConstraint *CPhysSlideConstraint::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-{

-	constraint_slidingparams_t sliding;

-	sliding.Defaults();

-	GetBreakParams( sliding.constraint, info );

-	sliding.constraint.strength = 1.0;

-

-	Vector axisDirection = m_axisEnd - GetAbsOrigin();

-	VectorNormalize( axisDirection );

-	UTIL_SnapDirectionToAxis( axisDirection );

-

-	sliding.InitWithCurrentObjectState( info.pObjects[0], info.pObjects[1], axisDirection );

-	sliding.friction = m_slideFriction;

-	if ( m_spawnflags & SF_SLIDE_LIMIT_ENDS )

-	{

-		Vector position;

-		info.pObjects[1]->GetPosition( &position, NULL );

-

-		sliding.limitMin = DotProduct( axisDirection, GetAbsOrigin() );

-		sliding.limitMax = DotProduct( axisDirection, m_axisEnd );

-		if ( sliding.limitMax < sliding.limitMin )

-		{

-			::V_swap( sliding.limitMin, sliding.limitMax );

-		}

-

-		// expand limits to make initial position of the attached object valid

-		float limit = DotProduct( position, axisDirection );

-		if ( limit < sliding.limitMin )

-		{

-			sliding.limitMin = limit;

-		}

-		else if ( limit > sliding.limitMax )

-		{

-			sliding.limitMax = limit;

-		}

-		// offset so that the current position is 0

-		sliding.limitMin -= limit;

-		sliding.limitMax -= limit;

-	}

-

-	return physenv->CreateSlidingConstraint( info.pObjects[0], info.pObjects[1], pGroup, sliding );

-}

-

-

-#if HINGE_NOTIFY

-void CPhysSlideConstraint::SoundThink( void )

-{

-	Assert(m_pConstraint);

-	if (!m_pConstraint)

-		return;

-

-	IPhysicsObject * pAttached = m_pConstraint->GetAttachedObject(), *pReference = m_pConstraint->GetReferenceObject();

-	Assert( pAttached && pReference );

-	if (pAttached && pReference)

-	{

-		Vector relativeVel = VelocitySampler::GetRelativeVelocity(pAttached,pReference);

-		// project velocity onto my primary axis.:

-

-		Vector axisDirection = m_axisEnd - GetAbsOrigin();

-		relativeVel = m_axisEnd * relativeVel.Dot(m_axisEnd)/m_axisEnd.Dot(m_axisEnd);

-

-		m_soundInfo.OnThink( this, relativeVel );

-

-		SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());

-	}

-

-}

-

-void CPhysSlideConstraint::Activate( void )

-{

-	BaseClass::Activate();

-

-	m_soundInfo.OnActivate(this);

-

-	Vector axisDirection = m_axisEnd - GetAbsOrigin();

-	VectorNormalize( axisDirection );

-	UTIL_SnapDirectionToAxis( axisDirection );

-	m_soundInfo.StartThinking(this, 

-		VelocitySampler::GetRelativeVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()),

-		axisDirection

-		);

-

-	SetThink(&CPhysSlideConstraint::SoundThink);

-	SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());

-}

-

-void CPhysSlideConstraint::Precache()

-{

-	m_soundInfo.OnPrecache(this);

-}

-

-#endif

-

-

-

-LINK_ENTITY_TO_CLASS( phys_constraint, CPhysFixed );

-

-//-----------------------------------------------------------------------------

-// Purpose: Activate/create the constraint

-//-----------------------------------------------------------------------------

-IPhysicsConstraint *CPhysFixed::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-{

-	constraint_fixedparams_t fixed;

-	fixed.Defaults();

-	fixed.InitWithCurrentObjectState( info.pObjects[0], info.pObjects[1] );

-	GetBreakParams( fixed.constraint, info );

-

-	// constraining to the world means object 1 is fixed

-	if ( info.pObjects[0] == g_PhysWorldObject )

-	{

-		PhysSetGameFlags( info.pObjects[1], FVPHYSICS_CONSTRAINT_STATIC );

-	}

-

-	return physenv->CreateFixedConstraint( info.pObjects[0], info.pObjects[1], pGroup, fixed );

-}

-

-

-//-----------------------------------------------------------------------------

-// Purpose: Breakable pulley w/ropes constraint

-//-----------------------------------------------------------------------------

-class CPhysPulley : public CPhysConstraint

-{

-	DECLARE_CLASS( CPhysPulley, CPhysConstraint );

-public:

-	DECLARE_DATADESC();

-

-	void DrawDebugGeometryOverlays()

-	{

-		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )

-		{

-			Vector origin = GetAbsOrigin();

-			Vector refPos = origin, attachPos = origin;

-			IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();

-			if ( pRef )

-			{

-				matrix3x4_t matrix;

-				pRef->GetPositionMatrix( &matrix );

-				VectorTransform( m_offset[0], matrix, refPos );

-			}

-			IPhysicsObject *pAttach = m_pConstraint->GetAttachedObject();

-			if ( pAttach )

-			{

-				matrix3x4_t matrix;

-				pAttach->GetPositionMatrix( &matrix );

-				VectorTransform( m_offset[1], matrix, attachPos );

-			}

-			NDebugOverlay::Line( refPos, origin, 0, 255, 0, false, 0 );

-			NDebugOverlay::Line( origin, m_position2, 128, 128, 128, false, 0 );

-			NDebugOverlay::Line( m_position2, attachPos, 0, 255, 0, false, 0 );

-			NDebugOverlay::Box( origin, -Vector(8,8,8), Vector(8,8,8), 128, 255, 128, 32, 0 );

-			NDebugOverlay::Box( m_position2, -Vector(8,8,8), Vector(8,8,8), 255, 128, 128, 32, 0 );

-		}

-		BaseClass::DrawDebugGeometryOverlays();

-	}

-

-	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );

-

-private:

-	Vector		m_position2;

-	Vector		m_offset[2];

-	float		m_addLength;

-	float		m_gearRatio;

-};

-

-BEGIN_DATADESC( CPhysPulley )

-

-	DEFINE_KEYFIELD( m_position2, FIELD_POSITION_VECTOR, "position2" ),

-	DEFINE_AUTO_ARRAY( m_offset, FIELD_VECTOR ),

-	DEFINE_KEYFIELD( m_addLength, FIELD_FLOAT, "addlength" ),

-	DEFINE_KEYFIELD( m_gearRatio, FIELD_FLOAT, "gearratio" ),

-

-END_DATADESC()

-

-

-LINK_ENTITY_TO_CLASS( phys_pulleyconstraint, CPhysPulley );

-

-

-//-----------------------------------------------------------------------------

-// Purpose: Activate/create the constraint

-//-----------------------------------------------------------------------------

-IPhysicsConstraint *CPhysPulley::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-{

-	constraint_pulleyparams_t pulley;

-	pulley.Defaults();

-	pulley.pulleyPosition[0] = GetAbsOrigin();

-	pulley.pulleyPosition[1] = m_position2;

-

-	matrix3x4_t matrix;

-	Vector world[2];

-

-	info.pObjects[0]->GetPositionMatrix( &matrix );

-	VectorTransform( info.anchorPosition[0], matrix, world[0] );

-	info.pObjects[1]->GetPositionMatrix( &matrix );

-	VectorTransform( info.anchorPosition[1], matrix, world[1] );

-

-	for ( int i = 0; i < 2; i++ )

-	{

-		pulley.objectPosition[i] = info.anchorPosition[i];

-		m_offset[i] = info.anchorPosition[i];

-	}

-	

-	pulley.totalLength = m_addLength + 

-		(world[0] - pulley.pulleyPosition[0]).Length() + 

-		((world[1] - pulley.pulleyPosition[1]).Length() * m_gearRatio);

-

-	if ( m_gearRatio != 0 )

-	{

-		pulley.gearRatio = m_gearRatio;

-	}

-	GetBreakParams( pulley.constraint, info );

-	if ( m_spawnflags & SF_PULLEY_RIGID )

-	{

-		pulley.isRigid = true;

-	}

-

-	return physenv->CreatePulleyConstraint( info.pObjects[0], info.pObjects[1], pGroup, pulley );

-}

-

-//-----------------------------------------------------------------------------

-// Purpose: Breakable rope/length constraint

-//-----------------------------------------------------------------------------

-class CPhysLength : public CPhysConstraint

-{

-	DECLARE_CLASS( CPhysLength, CPhysConstraint );

-public:

-	DECLARE_DATADESC();

-

-	void DrawDebugGeometryOverlays()

-	{

-		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )

-		{

-			Vector origin = GetAbsOrigin();

-			Vector refPos = origin, attachPos = origin;

-			IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();

-			if ( pRef )

-			{

-				matrix3x4_t matrix;

-				pRef->GetPositionMatrix( &matrix );

-				VectorTransform( m_offset[0], matrix, refPos );

-			}

-			IPhysicsObject *pAttach = m_pConstraint->GetAttachedObject();

-			if ( pAttach )

-			{

-				matrix3x4_t matrix;

-				pAttach->GetPositionMatrix( &matrix );

-				VectorTransform( m_offset[1], matrix, attachPos );

-			}

-			Vector dir = attachPos - refPos;

-

-			float len = VectorNormalize(dir);

-			if ( len > m_totalLength )

-			{

-				Vector mid = refPos + dir * m_totalLength;

-				NDebugOverlay::Line( refPos, mid, 0, 255, 0, false, 0 );

-				NDebugOverlay::Line( mid, attachPos, 255, 0, 0, false, 0 );

-			}

-			else

-			{

-				NDebugOverlay::Line( refPos, attachPos, 0, 255, 0, false, 0 );

-			}

-		}

-		BaseClass::DrawDebugGeometryOverlays();

-	}

-

-	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );

-

-private:

-	Vector		m_offset[2];

-	Vector		m_vecAttach;

-	float		m_addLength;

-	float		m_minLength;

-	float		m_totalLength;

-};

-

-BEGIN_DATADESC( CPhysLength )

-

-	DEFINE_AUTO_ARRAY( m_offset, FIELD_VECTOR ),

-	DEFINE_KEYFIELD( m_addLength, FIELD_FLOAT, "addlength" ),

-	DEFINE_KEYFIELD( m_minLength, FIELD_FLOAT, "minlength" ),

-	DEFINE_KEYFIELD( m_vecAttach, FIELD_POSITION_VECTOR, "attachpoint" ),

-	DEFINE_FIELD( m_totalLength, FIELD_FLOAT ),

-END_DATADESC()

-

-

-LINK_ENTITY_TO_CLASS( phys_lengthconstraint, CPhysLength );

-

-

-//-----------------------------------------------------------------------------

-// Purpose: Activate/create the constraint

-//-----------------------------------------------------------------------------

-IPhysicsConstraint *CPhysLength::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-{

-	constraint_lengthparams_t length;

-	length.Defaults();

-	Vector position[2];

-	position[0] = GetAbsOrigin();

-	position[1] = m_vecAttach;

-	int index = info.swapped ? 1 : 0;

-	length.InitWorldspace( info.pObjects[0], info.pObjects[1], position[index], position[!index] );

-	length.totalLength += m_addLength;

-	length.minLength = m_minLength;

-	m_totalLength = length.totalLength;

-	if ( HasSpawnFlags(SF_LENGTH_RIGID) )

-	{

-		length.minLength = length.totalLength;

-	}

-

-	for ( int i = 0; i < 2; i++ )

-	{

-		m_offset[i] = length.objectPosition[i];

-	}

-	GetBreakParams( length.constraint, info );

-

-	return physenv->CreateLengthConstraint( info.pObjects[0], info.pObjects[1], pGroup, length );

-}

-

-//-----------------------------------------------------------------------------

-// Purpose: Limited ballsocket constraint with toggle-able translation constraints

-//-----------------------------------------------------------------------------

-class CRagdollConstraint : public CPhysConstraint

-{

-	DECLARE_CLASS( CRagdollConstraint, CPhysConstraint );

-public:

-	DECLARE_DATADESC();

-#if 0

-	void DrawDebugGeometryOverlays()

-	{

-		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )

-		{

-			NDebugOverlay::Line( refPos, attachPos, 0, 255, 0, false, 0 );

-		}

-		BaseClass::DrawDebugGeometryOverlays();

-	}

-#endif

-

-	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );

-

-private:

-	float		m_xmin;	// constraint limits in degrees

-	float		m_xmax;

-	float		m_ymin;

-	float		m_ymax;

-	float		m_zmin;

-	float		m_zmax;

-

-	float		m_xfriction;

-	float		m_yfriction;

-	float		m_zfriction;

-};

-

-BEGIN_DATADESC( CRagdollConstraint )

-

-	DEFINE_KEYFIELD( m_xmin, FIELD_FLOAT, "xmin" ),

-	DEFINE_KEYFIELD( m_xmax, FIELD_FLOAT, "xmax" ),

-	DEFINE_KEYFIELD( m_ymin, FIELD_FLOAT, "ymin" ),

-	DEFINE_KEYFIELD( m_ymax, FIELD_FLOAT, "ymax" ),

-	DEFINE_KEYFIELD( m_zmin, FIELD_FLOAT, "zmin" ),

-	DEFINE_KEYFIELD( m_zmax, FIELD_FLOAT, "zmax" ),

-	DEFINE_KEYFIELD( m_xfriction, FIELD_FLOAT, "xfriction" ),

-	DEFINE_KEYFIELD( m_yfriction, FIELD_FLOAT, "yfriction" ),

-	DEFINE_KEYFIELD( m_zfriction, FIELD_FLOAT, "zfriction" ),

-

-END_DATADESC()

-

-

-LINK_ENTITY_TO_CLASS( phys_ragdollconstraint, CRagdollConstraint );

-

-//-----------------------------------------------------------------------------

-// Purpose: Activate/create the constraint

-//-----------------------------------------------------------------------------

-IPhysicsConstraint *CRagdollConstraint::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )

-{

-	constraint_ragdollparams_t ragdoll;

-	ragdoll.Defaults();

-

-	matrix3x4_t entityToWorld, worldToEntity;

-	info.pObjects[0]->GetPositionMatrix( &entityToWorld );

-	MatrixInvert( entityToWorld, worldToEntity );

-	ConcatTransforms( worldToEntity, EntityToWorldTransform(), ragdoll.constraintToReference );

-

-	info.pObjects[1]->GetPositionMatrix( &entityToWorld );

-	MatrixInvert( entityToWorld, worldToEntity );

-	ConcatTransforms( worldToEntity, EntityToWorldTransform(), ragdoll.constraintToAttached );

-

-	ragdoll.onlyAngularLimits = HasSpawnFlags( SF_RAGDOLL_FREEMOVEMENT ) ? true : false;

-

-	// FIXME: Why are these friction numbers in different units from what the hinge uses?

-	ragdoll.axes[0].SetAxisFriction( m_xmin, m_xmax, m_xfriction );

-	ragdoll.axes[1].SetAxisFriction( m_ymin, m_ymax, m_yfriction );

-	ragdoll.axes[2].SetAxisFriction( m_zmin, m_zmax, m_zfriction );

-

-	if ( HasSpawnFlags( SF_CONSTRAINT_START_INACTIVE ) )

-	{

-		ragdoll.isActive = false;

-	}

-	return physenv->CreateRagdollConstraint( info.pObjects[0], info.pObjects[1], pGroup, ragdoll );

-}

-

-

-

-class CPhysConstraintEvents : public IPhysicsConstraintEvent

-{

-	void ConstraintBroken( IPhysicsConstraint *pConstraint )

-	{

-		CBaseEntity *pEntity = (CBaseEntity *)pConstraint->GetGameData();

-		if ( pEntity )

-		{

-			IPhysicsConstraintEvent *pConstraintEvent = dynamic_cast<IPhysicsConstraintEvent*>( pEntity );

-			//Msg("Constraint broken %s\n", pEntity->GetDebugName() );

-			if ( pConstraintEvent )

-			{

-				pConstraintEvent->ConstraintBroken( pConstraint );

-			}

-			else

-			{

-				variant_t emptyVariant;

-				pEntity->AcceptInput( "ConstraintBroken", NULL, NULL, emptyVariant, 0 );

-			}

-		}

-	}

-};

-

-static CPhysConstraintEvents constraintevents;

-// registered in physics.cpp

-IPhysicsConstraintEvent *g_pConstraintEvents = &constraintevents;

-

-

-

-

-

-#if HINGE_NOTIFY

-//-----------------------------------------------------------------------------

-// Code for sampler

-//-----------------------------------------------------------------------------

-

-

-/// Call this in spawn(). (Not a constructor because those are difficult to use in entities.)

-void VelocitySampler::Initialize(float samplerate)

-{

-	m_fIdealSampleRate = samplerate;

-}

-

-// This is an old style approach to reversal sounds, from when there was only one.

-#if 0

-bool VelocitySampler::HasReversed(const Vector &relativeVelocity, float thresholdAcceleration)

-{

-	// first, make sure the velocity has reversed (is more than 90deg off) from last time, or is zero now.

-	// float rVsq = relativeVelocity.LengthSqr();

-	float vDot = relativeVelocity.Dot(m_prevSample);

-	if (vDot <= 0) // there is a reversal in direction. compute the magnitude of acceleration.

-	{

-		// find the scalar projection of the relative acceleration this fame onto the previous frame's

-		// velocity, and compare that to the threshold. 

-		Vector accel = relativeVelocity - m_prevSample;

-

-		float prevSampleLength = m_prevSample.Length();

-		float projection = 0;

-		// divide through by dt to get the accel per sec

-		if (prevSampleLength)

-		{

-			projection = -(accel.Dot(m_prevSample) / prevSampleLength) / (gpGlobals->curtime - m_fPrevSampleTime);

-		}

-		else

-		{

-			projection = accel.Length() / (gpGlobals->curtime - m_fPrevSampleTime);

-		}

-

-		if (g_debug_constraint_sounds.GetBool())

-		{

-			Msg("Reversal accel is %f/%f\n",projection,thresholdAcceleration);

-		}

-		return ((projection) > thresholdAcceleration); // the scalar projection is negative because the acceleration is against vel

-	}

-	else

-	{

-		return false;

-	}

-}

-#endif

-

-/// Looks at the force of reversal and compares it to a ladder of thresholds.

-/// Returns the index of the highest threshold exceeded by the reversal velocity. 

-int VelocitySampler::HasReversed(const Vector &relativeVelocity, const float thresholdAcceleration[], const unsigned short numThresholds)

-{

-	// first, make sure the velocity has reversed (is more than 90deg off) from last time, or is zero now.

-	// float rVsq = relativeVelocity.LengthSqr();

-	float vDot = relativeVelocity.Dot(m_prevSample);

-	if (vDot <= 0) // there is a reversal in direction. compute the magnitude of acceleration.

-	{

-		// find the scalar projection of the relative acceleration this fame onto the previous frame's

-		// velocity, and compare that to the threshold. 

-		Vector accel = relativeVelocity - m_prevSample;

-

-		float prevSampleLength = m_prevSample.Length();

-		float projection = 0;

-		// divide through by dt to get the accel per sec

-		if (prevSampleLength)

-		{

-			// the scalar projection is negative because the acceleration is against vel

-			projection = -(accel.Dot(m_prevSample) / prevSampleLength) / (gpGlobals->curtime - m_fPrevSampleTime);

-		}

-		else

-		{

-			projection = accel.Length() / (gpGlobals->curtime - m_fPrevSampleTime);

-		}

-

-		if (g_debug_constraint_sounds.GetBool())

-		{

-			Msg("Reversal accel is %f/%f\n", projection, thresholdAcceleration[0]);

-		}

-

-

-		// now find the threshold crossed.

-		int retval;

-		for (retval = numThresholds - 1; retval >= 0 ; --retval)

-		{

-			if (projection > thresholdAcceleration[retval])

-				break;

-		}

-

-		return retval; 

-	}

-	else

-	{

-		return -1;

-	}

-}

-

-/// small helper function used just below (technique copy-pasted  from sound.cpp)

-inline static bool IsEmpty (const string_t &str)

-{

-	return (!str || strlen(str.ToCStr()) < 1 );

-}

-

-void ConstraintSoundInfo::OnActivate( CPhysConstraint *pOuter )

-{

-	m_pTravelSound = NULL;

-	m_vSampler.Initialize( getThinkRate() );

-

-

-	ValidateInternals( pOuter );

-

-	// make sure sound filenames are not empty 

-	m_bPlayTravelSound   = !IsEmpty(m_iszTravelSoundFwd) || !IsEmpty(m_iszTravelSoundBack);

-	m_bPlayReversalSound = false;

-	for (int i = 0; i < SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE ; ++i)

-	{

-		if ( !IsEmpty(m_iszReversalSounds[i]) )

-		{

-			// if there is at least one filled sound field, we should try

-			// to play reversals

-			m_bPlayReversalSound = true;

-			break;

-		}

-	}

-

-

-	/*

-	SetThink(&CPhysSlideConstraint::SoundThink);

-	SetNextThink(gpGlobals->curtime + m_vSampler.getSampleRate());

-	*/

-}

-

-/// Maintain consistency of internal datastructures on start

-void ConstraintSoundInfo::ValidateInternals( CPhysConstraint *pOuter )

-{

-	// Make sure the reversal sound thresholds are strictly increasing.

-	for (int i = 1 ; i < SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE ; ++i)

-	{

-		// if decreases from small to medium, promote small to medium and warn.

-		if (m_soundProfile.m_reversalSoundThresholds[i] < m_soundProfile.m_reversalSoundThresholds[i-1])

-		{

-			Warning("Constraint reversal sounds for %s are out of order!", pOuter->GetDebugName() );

-			m_soundProfile.m_reversalSoundThresholds[i] = m_soundProfile.m_reversalSoundThresholds[i-1];

-			m_iszReversalSounds[i] = m_iszReversalSounds[i-1];

-		}

-	}

-}

-

-void ConstraintSoundInfo::OnPrecache( CPhysConstraint *pOuter )

-{

-	pOuter->PrecacheScriptSound( m_iszTravelSoundFwd.ToCStr() ); 

-	pOuter->PrecacheScriptSound( m_iszTravelSoundBack.ToCStr() ); 

-	for (int i = 0 ; i < SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE; ++i )

-	{

-		pOuter->PrecacheScriptSound( m_iszReversalSounds[i].ToCStr() );

-	}

-}

-

-void ConstraintSoundInfo::OnThink( CPhysConstraint *pOuter, const Vector &relativeVelocity )

-{

-	// have we had a hard reversal?

-	int playReversal = m_vSampler.HasReversed( relativeVelocity, m_soundProfile.m_reversalSoundThresholds, SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE );

-	float relativeVelMag = relativeVelocity.Length(); //< magnitude of relative velocity

-

-	CBaseEntity *pChildEntity = static_cast<CBaseEntity *>(pOuter->GetPhysConstraint()->GetAttachedObject()->GetGameData());

-

-	// compute sound level

-	float soundVol = this->m_soundProfile.GetVolume(relativeVelMag);

-

-	if (g_debug_constraint_sounds.GetBool())

-	{

-		char tempstr[512];

-		Q_snprintf(tempstr,sizeof(tempstr),"Velocity: %.3f", relativeVelMag );

-		pChildEntity->EntityText( 0, tempstr, m_vSampler.getSampleRate() );

-

-		Q_snprintf(tempstr,sizeof(tempstr),"Sound volume: %.3f", soundVol );

-		pChildEntity->EntityText( 1, tempstr, m_vSampler.getSampleRate() );

-

-		if (playReversal >= 0)

-		{

-			Q_snprintf(tempstr,sizeof(tempstr),"Reversal [%d]", playReversal );

-			pChildEntity->EntityText(2,tempstr,m_vSampler.getSampleRate());

-		}

-	}

-

-	// if we loaded a travel sound

-	if (m_bPlayTravelSound)

-	{

-		if (soundVol > 0)

-		{

-			// if we want to play a sound...

-			if ( m_pTravelSound )

-			{	// if a sound exists, modify it

-				CSoundEnvelopeController::GetController().SoundChangeVolume( m_pTravelSound, soundVol, 0.1f );

-			}

-			else

-			{	// if a sound does not exist, create it

-				bool travellingForward = relativeVelocity.Dot(m_forwardAxis) > 0;

-

-				CSoundEnvelopeController &controller = CSoundEnvelopeController::GetController();

-				CPASAttenuationFilter filter( pChildEntity );

-				m_pTravelSound = controller.SoundCreate( filter, pChildEntity->entindex(), 

-					(travellingForward ? m_iszTravelSoundFwd : m_iszTravelSoundBack).ToCStr() );

-				controller.Play( m_pTravelSound, soundVol, 100 );

-			}

-		}

-		else

-		{

-			// if we want to not play sound

-			if ( m_pTravelSound )

-			{	// and it exists, kill it

-				CSoundEnvelopeController::GetController().SoundDestroy( m_pTravelSound );

-				m_pTravelSound = NULL;

-			}

-		}

-	}

-

-	if (m_bPlayReversalSound && (playReversal >= 0))

-	{

-		pChildEntity->EmitSound(m_iszReversalSounds[playReversal].ToCStr());

-	}

-

-	m_vSampler.AddSample( relativeVelocity );

-	

-}

-

-

-void ConstraintSoundInfo::StartThinking( CPhysConstraint *pOuter, const Vector &relativeVelocity, const Vector &forwardVector )

-{

-	m_forwardAxis = forwardVector;

-	m_vSampler.BeginSampling( relativeVelocity );

-

-	/*

-	IPhysicsConstraint *pConstraint = pOuter->GetPhysConstraint();

-	Assert(pConstraint);

-	if (pConstraint)

-	{

-		IPhysicsObject * pAttached = pConstraint->GetAttachedObject(), *pReference = pConstraint->GetReferenceObject();

-		m_vSampler.BeginSampling( VelocitySampler::GetRelativeVelocity(pAttached,pReference) );

-	}

-	*/

-}

-

-void ConstraintSoundInfo::StopThinking( CPhysConstraint *pOuter )

-{

-	DeleteAllSounds();

-}

-

-

-ConstraintSoundInfo::~ConstraintSoundInfo()

-{

-	DeleteAllSounds();

-}

-

-// Any sounds envelopes that are active, kill.

-void ConstraintSoundInfo::DeleteAllSounds()

-{

-	if ( m_pTravelSound )

-	{

-		CSoundEnvelopeController::GetController().SoundDestroy( m_pTravelSound );

-		m_pTravelSound = NULL;

-	}

-}

-

-#endif

+//========= Copyright Valve Corporation, All rights reserved. ============//
+//
+// Purpose: Physics constraint entities
+//
+// $NoKeywords: $
+//===========================================================================//
+
+#include "cbase.h"
+#include "physics.h"
+#include "entityoutput.h"
+#include "engine/IEngineSound.h"
+#include "igamesystem.h"
+#include "physics_saverestore.h"
+#include "vcollide_parse.h"
+#include "positionwatcher.h"
+#include "fmtstr.h"
+#include "physics_prop_ragdoll.h"
+
+#define HINGE_NOTIFY HL2_EPISODIC
+#if HINGE_NOTIFY
+#include "physconstraint_sounds.h"
+#endif
+
+#include "physconstraint.h"
+
+// memdbgon must be the last include file in a .cpp file!!!
+#include "tier0/memdbgon.h"
+
+#define SF_CONSTRAINT_DISABLE_COLLISION			0x0001
+#define SF_SLIDE_LIMIT_ENDS						0x0002
+#define SF_PULLEY_RIGID							0x0002
+#define SF_LENGTH_RIGID							0x0002
+#define SF_RAGDOLL_FREEMOVEMENT					0x0002
+#define SF_CONSTRAINT_START_INACTIVE			0x0004
+#define SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY		0x0008
+#define SF_CONSTRAINT_NO_CONNECT_UNTIL_ACTIVATED	0x0010	// Will only check the two attached entities at activation
+
+
+ConVar    g_debug_constraint_sounds	  ( "g_debug_constraint_sounds", "0", FCVAR_CHEAT, "Enable debug printing about constraint sounds.");
+
+struct constraint_anchor_t
+{
+	Vector		localOrigin;
+	EHANDLE		hEntity;
+	int			parentAttachment;
+	string_t	name;
+	float		massScale;
+};
+
+class CAnchorList : public CAutoGameSystem
+{
+public:
+	CAnchorList( char const *name ) : CAutoGameSystem( name )
+	{
+	}
+	void LevelShutdownPostEntity() 
+	{
+		m_list.Purge();
+	}
+
+	void AddToList( CBaseEntity *pEntity, float massScale )
+	{
+		int index = m_list.AddToTail();
+		constraint_anchor_t *pAnchor = &m_list[index];
+
+		pAnchor->hEntity = pEntity->GetParent();
+		pAnchor->parentAttachment = pEntity->GetParentAttachment();
+		pAnchor->name = pEntity->GetEntityName();
+		pAnchor->localOrigin = pEntity->GetLocalOrigin();
+		pAnchor->massScale = massScale;
+	}
+
+	constraint_anchor_t *Find( string_t name )
+	{
+		for ( int i = m_list.Count()-1; i >=0; i-- )
+		{
+			if ( FStrEq( STRING(m_list[i].name), STRING(name) ) )
+			{
+				return &m_list[i];
+			}
+		}
+		return NULL;
+	}
+
+private:
+	CUtlVector<constraint_anchor_t>	m_list;
+};
+
+static CAnchorList g_AnchorList( "CAnchorList" );
+
+class CConstraintAnchor : public CPointEntity
+{
+	DECLARE_CLASS( CConstraintAnchor, CPointEntity );
+public:
+	CConstraintAnchor()
+	{
+		m_massScale = 1.0f;
+	}
+	void Spawn( void )
+	{
+		if ( GetParent() )
+		{
+			g_AnchorList.AddToList( this, m_massScale );
+			UTIL_Remove( this );
+		}
+	}
+	DECLARE_DATADESC();
+
+	float m_massScale;
+};
+
+BEGIN_DATADESC( CConstraintAnchor )
+	DEFINE_KEYFIELD( m_massScale, FIELD_FLOAT, "massScale" ),
+END_DATADESC()
+
+LINK_ENTITY_TO_CLASS( info_constraint_anchor, CConstraintAnchor );
+
+class CPhysConstraintSystem : public CLogicalEntity
+{
+	DECLARE_CLASS( CPhysConstraintSystem, CLogicalEntity );
+public:
+
+	void Spawn();
+	IPhysicsConstraintGroup *GetVPhysicsGroup() { return m_pMachine; }
+
+	DECLARE_DATADESC();
+private:
+	IPhysicsConstraintGroup *m_pMachine;
+	int						m_additionalIterations;
+};
+
+BEGIN_DATADESC( CPhysConstraintSystem )
+	DEFINE_PHYSPTR( m_pMachine ),
+	DEFINE_KEYFIELD( m_additionalIterations, FIELD_INTEGER, "additionaliterations" ),
+	
+END_DATADESC()
+
+
+void CPhysConstraintSystem::Spawn()
+{
+	constraint_groupparams_t group;
+	group.Defaults();
+	group.additionalIterations = m_additionalIterations;
+	m_pMachine = physenv->CreateConstraintGroup( group );
+}
+
+LINK_ENTITY_TO_CLASS( phys_constraintsystem, CPhysConstraintSystem );
+
+void PhysTeleportConstrainedEntity( CBaseEntity *pTeleportSource, IPhysicsObject *pObject0, IPhysicsObject *pObject1, const Vector &prevPosition, const QAngle &prevAngles, bool physicsRotate )
+{
+	// teleport the other object
+	CBaseEntity *pEntity0 = static_cast<CBaseEntity *> (pObject0->GetGameData());
+	CBaseEntity *pEntity1 = static_cast<CBaseEntity *> (pObject1->GetGameData());
+	if ( !pEntity0 || !pEntity1 )
+		return;
+
+	// figure out which entity needs to be fixed up (the one that isn't pTeleportSource)
+	CBaseEntity *pFixup = pEntity1;
+	// teleport the other object
+	if ( pTeleportSource != pEntity0 )
+	{
+		if ( pTeleportSource != pEntity1 )
+		{
+			Msg("Bogus teleport notification!!\n");
+			return;
+		}
+		pFixup = pEntity0;
+	}
+
+	// constraint doesn't move this entity
+	if ( pFixup->GetMoveType() != MOVETYPE_VPHYSICS )
+		return;
+
+	if ( !pFixup->VPhysicsGetObject() || !pFixup->VPhysicsGetObject()->IsMoveable() )
+		return;
+
+	QAngle oldAngles = prevAngles;
+
+	if ( !physicsRotate )
+	{
+		oldAngles = pTeleportSource->GetAbsAngles();
+	}
+
+	matrix3x4_t startCoord, startInv, endCoord, xform;
+	AngleMatrix( oldAngles, prevPosition, startCoord );
+	MatrixInvert( startCoord, startInv );
+	ConcatTransforms( pTeleportSource->EntityToWorldTransform(), startInv, xform );
+	QAngle fixupAngles;
+	Vector fixupPos;
+
+	ConcatTransforms( xform, pFixup->EntityToWorldTransform(), endCoord );
+	MatrixAngles( endCoord, fixupAngles, fixupPos );
+	pFixup->Teleport( &fixupPos, &fixupAngles, NULL );
+}
+
+static void DrawPhysicsBounds( IPhysicsObject *pObject, int r, int g, int b, int a )
+{
+	const CPhysCollide *pCollide = pObject->GetCollide();
+	Vector pos;
+	QAngle angles;
+	pObject->GetPosition( &pos, &angles );
+	Vector mins, maxs;
+	physcollision->CollideGetAABB( &mins, &maxs, pCollide, vec3_origin, vec3_angle );
+	// don't fight the z-buffer
+	mins -= Vector(1,1,1);
+	maxs += Vector(1,1,1);
+	NDebugOverlay::BoxAngles( pos, mins, maxs, angles, r, g, b, a, 0 );
+}
+
+static void DrawConstraintObjectsAxes(CBaseEntity *pConstraintEntity, IPhysicsConstraint *pConstraint)
+{
+	if ( !pConstraint || !pConstraintEntity )
+		return;
+	matrix3x4_t xformRef, xformAtt;
+	bool bXform = pConstraint->GetConstraintTransform( &xformRef, &xformAtt );
+	IPhysicsObject *pRef = pConstraint->GetReferenceObject();
+
+	if ( pRef && !pRef->IsStatic() )
+	{
+		if ( bXform )
+		{
+			Vector pos, posWorld;
+			QAngle angles;
+			MatrixAngles( xformRef, angles, pos );
+			pRef->LocalToWorld( &posWorld, pos );
+			NDebugOverlay::Axis( posWorld, vec3_angle, 12, false, 0 );
+		}
+		DrawPhysicsBounds( pRef, 0, 255, 0, 12 );
+	}
+	IPhysicsObject *pAttach = pConstraint->GetAttachedObject();
+	if ( pAttach && !pAttach->IsStatic() )
+	{
+		if ( bXform )
+		{
+			Vector pos, posWorld;
+			QAngle angles;
+			MatrixAngles( xformAtt, angles, pos );
+			pAttach->LocalToWorld( &posWorld, pos );
+			NDebugOverlay::Axis( posWorld, vec3_angle, 12, false, 0 );
+		}
+		DrawPhysicsBounds( pAttach, 255, 0, 0, 12 );
+	}
+}
+
+void CPhysConstraint::ClearStaticFlag( IPhysicsObject *pObj )
+{
+	if ( !pObj )
+		return;
+	PhysClearGameFlags( pObj, FVPHYSICS_CONSTRAINT_STATIC );
+}
+
+void CPhysConstraint::Deactivate()
+{
+	if ( !m_pConstraint )
+		return;
+	m_pConstraint->Deactivate();
+	ClearStaticFlag( m_pConstraint->GetReferenceObject() );
+	ClearStaticFlag( m_pConstraint->GetAttachedObject() );
+	if ( m_spawnflags & SF_CONSTRAINT_DISABLE_COLLISION )
+	{
+		// constraint may be getting deactivated because an object got deleted, so check them here.
+		IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();
+		IPhysicsObject *pAtt = m_pConstraint->GetAttachedObject();
+		if ( pRef && pAtt )
+		{
+			PhysEnableEntityCollisions( pRef, pAtt );
+		}
+	}
+}
+
+void CPhysConstraint::OnBreak( void )
+{
+	Deactivate();
+	if ( m_breakSound != NULL_STRING )
+	{
+		CPASAttenuationFilter filter( this, ATTN_STATIC );
+
+		Vector origin = GetAbsOrigin();
+		Vector refPos = origin, attachPos = origin;
+
+		IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();
+		if ( pRef && (pRef != g_PhysWorldObject) )
+		{
+			pRef->GetPosition( &refPos, NULL );
+			attachPos = refPos;
+		}
+		IPhysicsObject *pAttach = m_pConstraint->GetAttachedObject();
+		if ( pAttach && (pAttach != g_PhysWorldObject) )
+		{
+			pAttach->GetPosition( &attachPos, NULL );
+			if ( !pRef || (pRef == g_PhysWorldObject) )
+			{
+				refPos = attachPos;
+			}
+		}
+		
+		VectorAdd( refPos, attachPos, origin );
+		origin *= 0.5f;
+
+		EmitSound_t ep;
+		ep.m_nChannel = CHAN_STATIC;
+		ep.m_pSoundName = STRING(m_breakSound);
+		ep.m_flVolume = VOL_NORM;
+		ep.m_SoundLevel = ATTN_TO_SNDLVL( ATTN_STATIC );
+		ep.m_pOrigin = &origin;
+
+		EmitSound( filter, entindex(), ep );
+	}
+	m_OnBreak.FireOutput( this, this );
+	// queue this up to be deleted at the end of physics 
+	// The Deactivate() call should make sure we don't get more of these callbacks.
+	PhysCallbackRemove( this->NetworkProp() );
+}
+
+void CPhysConstraint::InputBreak( inputdata_t &inputdata )
+{
+	if ( m_pConstraint ) 
+		m_pConstraint->Deactivate();
+	
+	OnBreak();
+}
+
+void CPhysConstraint::InputOnBreak( inputdata_t &inputdata )
+{
+	OnBreak();
+}
+
+void CPhysConstraint::InputTurnOn( inputdata_t &inputdata )
+{
+	if ( HasSpawnFlags( SF_CONSTRAINT_NO_CONNECT_UNTIL_ACTIVATED ) )
+	{
+		ActivateConstraint();
+	}
+
+	if ( !m_pConstraint || !m_pConstraint->GetReferenceObject() || !m_pConstraint->GetAttachedObject() )
+		return;
+
+	m_pConstraint->Activate();
+	m_pConstraint->GetReferenceObject()->Wake();
+	m_pConstraint->GetAttachedObject()->Wake();
+}
+
+void CPhysConstraint::InputTurnOff( inputdata_t &inputdata )
+{
+	Deactivate();
+}
+
+int CPhysConstraint::DrawDebugTextOverlays()
+{
+	int pos = BaseClass::DrawDebugTextOverlays();
+	if ( m_pConstraint && (m_debugOverlays & OVERLAY_TEXT_BIT) )
+	{
+		constraint_breakableparams_t params;
+		Q_memset(&params,0,sizeof(params));
+		m_pConstraint->GetConstraintParams( &params );
+		
+		if ( (params.bodyMassScale[0] != 1.0f && params.bodyMassScale[0] != 0.0f) || (params.bodyMassScale[1] != 1.0f && params.bodyMassScale[1] != 0.0f) )
+		{
+			CFmtStr str("mass ratio %.4f:%.4f\n", params.bodyMassScale[0], params.bodyMassScale[1] );
+			NDebugOverlay::EntityTextAtPosition( GetAbsOrigin(), pos, str.Access(), 0, 255, 255, 0, 255 );
+		}
+		pos++;
+	}
+	return pos;
+}
+
+void CPhysConstraint::DrawDebugGeometryOverlays()
+{
+	if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )
+	{
+		DrawConstraintObjectsAxes(this, m_pConstraint);
+	}
+	BaseClass::DrawDebugGeometryOverlays();
+}
+
+void CPhysConstraint::GetBreakParams( constraint_breakableparams_t &params, const hl_constraint_info_t &info )
+{
+	params.Defaults();
+	params.forceLimit = lbs2kg(m_forceLimit);
+	params.torqueLimit = lbs2kg(m_torqueLimit);
+	params.isActive = HasSpawnFlags( SF_CONSTRAINT_START_INACTIVE ) ? false : true;
+	params.bodyMassScale[0] = info.massScale[0];
+	params.bodyMassScale[1] = info.massScale[1];
+}
+
+BEGIN_DATADESC( CPhysConstraint )
+
+	DEFINE_PHYSPTR( m_pConstraint ),
+
+	DEFINE_KEYFIELD( m_nameSystem, FIELD_STRING, "constraintsystem" ),
+	DEFINE_KEYFIELD( m_nameAttach1, FIELD_STRING, "attach1" ),
+	DEFINE_KEYFIELD( m_nameAttach2, FIELD_STRING, "attach2" ),
+	DEFINE_KEYFIELD( m_breakSound, FIELD_SOUNDNAME, "breaksound" ),
+	DEFINE_KEYFIELD( m_forceLimit, FIELD_FLOAT, "forcelimit" ),
+	DEFINE_KEYFIELD( m_torqueLimit, FIELD_FLOAT, "torquelimit" ),
+	DEFINE_KEYFIELD( m_minTeleportDistance, FIELD_FLOAT, "teleportfollowdistance" ),
+//	DEFINE_FIELD( m_teleportTick, FIELD_INTEGER ),
+
+	DEFINE_OUTPUT( m_OnBreak, "OnBreak" ),
+
+	DEFINE_INPUTFUNC( FIELD_VOID, "Break", InputBreak ),
+	DEFINE_INPUTFUNC( FIELD_VOID, "ConstraintBroken", InputOnBreak ),
+
+	DEFINE_INPUTFUNC( FIELD_VOID, "TurnOn", InputTurnOn ),
+	DEFINE_INPUTFUNC( FIELD_VOID, "TurnOff", InputTurnOff ),
+
+END_DATADESC()
+
+
+CPhysConstraint::CPhysConstraint( void )
+{
+	m_pConstraint = NULL;
+	m_nameAttach1 = NULL_STRING;
+	m_nameAttach2 = NULL_STRING;
+	m_forceLimit = 0;
+	m_torqueLimit = 0;
+	m_teleportTick = 0xFFFFFFFF;
+	m_minTeleportDistance = 0.0f;
+}
+
+CPhysConstraint::~CPhysConstraint()
+{
+	Deactivate();
+	physenv->DestroyConstraint( m_pConstraint );
+}
+
+void CPhysConstraint::Precache( void )
+{
+	if ( m_breakSound != NULL_STRING )
+	{
+		PrecacheScriptSound( STRING(m_breakSound) );
+	}
+}
+
+void CPhysConstraint::Spawn( void )
+{
+	BaseClass::Spawn();
+
+	Precache();
+}
+
+// debug function - slow, uses dynamic_cast<> - use this to query the attached objects
+// physics_debug_entity toggles the constraint system for an object using this
+bool GetConstraintAttachments( CBaseEntity *pEntity, CBaseEntity *pAttachOut[2], IPhysicsObject *pAttachVPhysics[2] )
+{
+	CPhysConstraint *pConstraintEntity = dynamic_cast<CPhysConstraint *>(pEntity);
+	if ( pConstraintEntity )
+	{
+		IPhysicsConstraint *pConstraint = pConstraintEntity->GetPhysConstraint();
+		if ( pConstraint )
+		{
+			IPhysicsObject *pRef = pConstraint->GetReferenceObject();
+			pAttachVPhysics[0] = pRef;
+			pAttachOut[0] = pRef ? static_cast<CBaseEntity *>(pRef->GetGameData()) : NULL;
+			IPhysicsObject *pAttach = pConstraint->GetAttachedObject();
+			pAttachVPhysics[1] = pAttach;
+			pAttachOut[1] = pAttach ? static_cast<CBaseEntity *>(pAttach->GetGameData()) : NULL;
+			return true;
+		}
+	}
+	return false;
+}
+
+void DebugConstraint(CBaseEntity *pEntity)
+{
+	CPhysConstraint *pConstraintEntity = dynamic_cast<CPhysConstraint *>(pEntity);
+	if ( pConstraintEntity )
+	{
+		IPhysicsConstraint *pConstraint = pConstraintEntity->GetPhysConstraint();
+		if ( pConstraint )
+		{
+			pConstraint->OutputDebugInfo();
+		}
+	}
+}
+
+
+void FindPhysicsAnchor( string_t name, hl_constraint_info_t &info, int index, CBaseEntity *pErrorEntity )
+{
+	constraint_anchor_t *pAnchor = g_AnchorList.Find( name );
+	if ( pAnchor )
+	{
+		CBaseEntity *pEntity = pAnchor->hEntity;
+		if ( pEntity )
+		{
+			info.massScale[index] = pAnchor->massScale;
+			bool bWroteAttachment = false;
+			if ( pAnchor->parentAttachment > 0 )
+			{
+				CBaseAnimating *pAnim = pAnchor->hEntity->GetBaseAnimating();
+				if ( pAnim )
+				{
+					IPhysicsObject *list[VPHYSICS_MAX_OBJECT_LIST_COUNT];
+					int listCount = pAnchor->hEntity->VPhysicsGetObjectList( list, ARRAYSIZE(list) );
+					int iPhysicsBone = pAnim->GetPhysicsBone( pAnim->GetAttachmentBone( pAnchor->parentAttachment ) );
+					if ( iPhysicsBone < listCount )
+					{
+						Vector pos;
+						info.pObjects[index] = list[iPhysicsBone];
+						pAnim->GetAttachment( pAnchor->parentAttachment, pos );
+						list[iPhysicsBone]->WorldToLocal( &info.anchorPosition[index], pos );
+						bWroteAttachment = true;
+					}
+				}
+			}
+			if ( !bWroteAttachment )
+			{
+				info.anchorPosition[index] = pAnchor->localOrigin;
+				info.pObjects[index] = pAnchor->hEntity->VPhysicsGetObject();
+			}
+		}
+		else
+		{
+			pAnchor = NULL;
+		}
+	}
+	if ( !pAnchor )
+	{
+		info.anchorPosition[index] = vec3_origin;
+		info.pObjects[index] = FindPhysicsObjectByName( STRING(name), pErrorEntity );
+		info.massScale[index] = 1.0f;
+	}
+}
+
+void CPhysConstraint::OnConstraintSetup( hl_constraint_info_t &info )
+{
+	if ( info.pObjects[0] && info.pObjects[1] )
+	{
+		SetupTeleportationHandling( info );
+	}
+	if ( m_spawnflags & SF_CONSTRAINT_DISABLE_COLLISION )
+	{
+		PhysDisableEntityCollisions( info.pObjects[0], info.pObjects[1] );
+	}
+}
+
+void CPhysConstraint::SetupTeleportationHandling( hl_constraint_info_t &info )
+{
+	CBaseEntity *pEntity0 = (CBaseEntity *)info.pObjects[0]->GetGameData();
+	if ( pEntity0 )
+	{
+		g_pNotify->AddEntity( this, pEntity0 );
+	}
+
+	CBaseEntity *pEntity1 = (CBaseEntity *)info.pObjects[1]->GetGameData();
+	if ( pEntity1 )
+	{
+		g_pNotify->AddEntity( this, pEntity1 );
+	}
+}
+
+static IPhysicsConstraintGroup *GetRagdollConstraintGroup( IPhysicsObject *pObj )
+{
+	if ( pObj )
+	{
+		CBaseEntity *pEntity = static_cast<CBaseEntity *>(pObj->GetGameData());
+		ragdoll_t *pRagdoll = Ragdoll_GetRagdoll(pEntity);
+		if ( pRagdoll )
+			return pRagdoll->pGroup;
+	}
+	return NULL;
+}
+
+void CPhysConstraint::GetConstraintObjects( hl_constraint_info_t &info )
+{
+	FindPhysicsAnchor( m_nameAttach1, info, 0, this );
+	FindPhysicsAnchor( m_nameAttach2, info, 1, this );
+
+	// Missing one object, assume the world instead
+	if ( info.pObjects[0] == NULL && info.pObjects[1] )
+	{
+		if ( Q_strlen(STRING(m_nameAttach1)) )
+		{
+			Warning("Bogus constraint %s (attaches ENTITY NOT FOUND:%s to %s)\n", GetDebugName(), STRING(m_nameAttach1), STRING(m_nameAttach2));
+#ifdef HL2_EPISODIC
+			info.pObjects[0] = info.pObjects[1] = NULL;
+			return;
+#endif	// HL2_EPISODIC
+		}
+		info.pObjects[0] = g_PhysWorldObject;
+		info.massScale[0] = info.massScale[1] = 1.0f; // no mass scale on world constraint
+	}
+	else if ( info.pObjects[0] && !info.pObjects[1] )
+	{
+		if ( Q_strlen(STRING(m_nameAttach2)) )
+		{
+			Warning("Bogus constraint %s (attaches %s to ENTITY NOT FOUND:%s)\n", GetDebugName(), STRING(m_nameAttach1), STRING(m_nameAttach2));
+#ifdef HL2_EPISODIC
+			info.pObjects[0] = info.pObjects[1] = NULL;
+			return;
+#endif	// HL2_EPISODIC
+		}
+		info.pObjects[1] = info.pObjects[0];
+		info.pObjects[0] = g_PhysWorldObject;		// Try to make the world object consistently object0 for ease of implementation
+		info.massScale[0] = info.massScale[1] = 1.0f; // no mass scale on world constraint
+		info.swapped = true;
+	}
+
+	info.pGroup = GetRagdollConstraintGroup(info.pObjects[0]);
+	if ( !info.pGroup )
+	{
+		info.pGroup = GetRagdollConstraintGroup(info.pObjects[1]);
+	}
+}
+
+void CPhysConstraint::Activate( void )
+{
+	BaseClass::Activate();
+
+	if ( HasSpawnFlags( SF_CONSTRAINT_NO_CONNECT_UNTIL_ACTIVATED ) == false )
+	{
+		if ( !ActivateConstraint() )
+		{
+			UTIL_Remove(this);
+		}
+	}
+}
+
+IPhysicsConstraintGroup *GetConstraintGroup( string_t systemName )
+{
+	CBaseEntity *pMachine = gEntList.FindEntityByName( NULL, systemName );
+
+	if ( pMachine )
+	{
+		CPhysConstraintSystem *pGroup = dynamic_cast<CPhysConstraintSystem *>(pMachine);
+		if ( pGroup )
+		{
+			return pGroup->GetVPhysicsGroup();
+		}
+	}
+	return NULL;
+}
+
+bool CPhysConstraint::ActivateConstraint( void )
+{
+	// A constraint attaches two objects to each other.
+	// The constraint is specified in the coordinate frame of the "reference" object
+	// and constrains the "attached" object
+	hl_constraint_info_t info;
+	if ( m_pConstraint )
+	{
+		// already have a constraint, don't make a new one
+		info.pObjects[0] = m_pConstraint->GetReferenceObject();
+		info.pObjects[1] = m_pConstraint->GetAttachedObject();
+		OnConstraintSetup(info);
+		return true;
+	}
+
+	GetConstraintObjects( info );
+	if ( !info.pObjects[0] && !info.pObjects[1] )
+		return false;
+
+	if ( info.pObjects[0]->IsStatic() && info.pObjects[1]->IsStatic() )
+	{
+		Warning("Constraint (%s) attached to two static objects (%s and %s)!!!\n", STRING(GetEntityName()), STRING(m_nameAttach1), m_nameAttach2 == NULL_STRING ? "world" : STRING(m_nameAttach2) );
+		return false;
+	}
+
+	if ( info.pObjects[0]->GetShadowController() && info.pObjects[1]->GetShadowController() )
+	{
+		Warning("Constraint (%s) attached to two shadow objects (%s and %s)!!!\n", STRING(GetEntityName()), STRING(m_nameAttach1), m_nameAttach2 == NULL_STRING ? "world" : STRING(m_nameAttach2) );
+		return false;
+	}
+	IPhysicsConstraintGroup *pGroup = GetConstraintGroup( m_nameSystem );
+	if ( !pGroup )
+	{
+		pGroup = info.pGroup;
+	}
+	m_pConstraint = CreateConstraint( pGroup, info );
+	if ( !m_pConstraint )
+		return false;
+
+	m_pConstraint->SetGameData( (void *)this );
+
+	if ( pGroup )
+	{
+		pGroup->Activate();
+	}
+
+	OnConstraintSetup(info);
+
+	return true;
+}
+
+void CPhysConstraint::NotifySystemEvent( CBaseEntity *pNotify, notify_system_event_t eventType, const notify_system_event_params_t &params )
+{
+	// don't recurse
+	if ( eventType != NOTIFY_EVENT_TELEPORT || (unsigned int)gpGlobals->tickcount == m_teleportTick )
+		return;
+
+	float distance = (params.pTeleport->prevOrigin - pNotify->GetAbsOrigin()).Length();
+	
+	// no need to follow a small teleport
+	if ( distance <= m_minTeleportDistance )
+		return;
+
+	m_teleportTick = gpGlobals->tickcount;
+
+	PhysTeleportConstrainedEntity( pNotify, m_pConstraint->GetReferenceObject(), m_pConstraint->GetAttachedObject(), params.pTeleport->prevOrigin, params.pTeleport->prevAngles, params.pTeleport->physicsRotate );
+}
+
+class CPhysHinge : public CPhysConstraint, public IVPhysicsWatcher
+{
+	DECLARE_CLASS( CPhysHinge, CPhysConstraint );
+
+public:
+	void Spawn( void );
+	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+	{
+		if ( m_hinge.worldAxisDirection == vec3_origin )
+		{
+			DevMsg("ERROR: Hinge with bad data!!!\n" );
+			return NULL;
+		}
+		GetBreakParams( m_hinge.constraint, info );
+		m_hinge.constraint.strength = 1.0;
+		// BUGBUG: These numbers are very hard to edit
+		// Scale by 1000 to make things easier
+		// CONSIDER: Unify the units of torque around something other 
+		// than HL units (kg * in^2 / s ^2)
+		m_hinge.hingeAxis.SetAxisFriction( 0, 0, m_hingeFriction * 1000 );
+
+		int hingeAxis;
+		if ( IsWorldHinge( info, &hingeAxis ) )
+		{
+			info.pObjects[1]->BecomeHinged( hingeAxis );
+		}
+		else
+		{
+			RemoveSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY );
+		}
+
+		return physenv->CreateHingeConstraint( info.pObjects[0], info.pObjects[1], pGroup, m_hinge );
+	}
+
+	void DrawDebugGeometryOverlays()
+	{
+		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )
+		{
+			NDebugOverlay::Line(m_hinge.worldPosition, m_hinge.worldPosition + 48 * m_hinge.worldAxisDirection, 0, 255, 0, false, 0 );
+		}
+		BaseClass::DrawDebugGeometryOverlays();
+	}
+
+	void InputSetVelocity( inputdata_t &inputdata )
+	{
+		if ( !m_pConstraint || !m_pConstraint->GetReferenceObject() || !m_pConstraint->GetAttachedObject() )
+			return;
+	
+		float speed = inputdata.value.Float();
+		float massLoad = 1;
+		int numMasses = 0;
+		if ( m_pConstraint->GetReferenceObject()->IsMoveable() )
+		{
+			massLoad = m_pConstraint->GetReferenceObject()->GetInertia().Length();
+			numMasses++;
+			m_pConstraint->GetReferenceObject()->Wake();
+		}
+		if ( m_pConstraint->GetAttachedObject()->IsMoveable() )
+		{
+			massLoad += m_pConstraint->GetAttachedObject()->GetInertia().Length();
+			numMasses++;
+			m_pConstraint->GetAttachedObject()->Wake();
+		}
+		if ( numMasses > 0 )
+		{
+			massLoad /= (float)numMasses;
+		}
+		
+		float loadscale = m_systemLoadScale != 0 ? m_systemLoadScale : 1;
+		m_pConstraint->SetAngularMotor( speed, speed * loadscale * massLoad * loadscale * (1.0/TICK_INTERVAL) );
+	}
+
+	void InputSetHingeFriction( inputdata_t &inputdata )
+	{
+		m_hingeFriction = inputdata.value.Float();
+		Msg("Setting hinge friction to %f\n", m_hingeFriction );
+		m_hinge.hingeAxis.SetAxisFriction( 0, 0, m_hingeFriction * 1000 );
+	}
+
+	virtual void Deactivate()
+	{
+		if ( HasSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY ) )
+		{
+			if ( m_pConstraint && m_pConstraint->GetAttachedObject() )
+			{
+				// NOTE: RemoveHinged() is always safe
+				m_pConstraint->GetAttachedObject()->RemoveHinged();
+			}
+		}
+
+		BaseClass::Deactivate();
+	}
+	
+	void NotifyVPhysicsStateChanged( IPhysicsObject *pPhysics, CBaseEntity *pEntity, bool bAwake )
+	{
+#if HINGE_NOTIFY
+		Assert(m_pConstraint);
+		if (!m_pConstraint) 
+			return;
+
+		// if something woke up, start thinking. If everything is asleep, stop thinking.
+		if ( bAwake )
+		{
+			// Did something wake up when I was not thinking?
+			if ( GetNextThink() == TICK_NEVER_THINK )
+			{
+				m_soundInfo.StartThinking(this, 
+					VelocitySampler::GetRelativeAngularVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()) ,
+					m_hinge.worldAxisDirection
+					);
+
+				SetThink(&CPhysHinge::SoundThink);
+				SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());
+			}
+		}
+		else
+		{
+			// Is everything asleep? If so, stop thinking.
+			if ( GetNextThink() != TICK_NEVER_THINK				&&
+				m_pConstraint->GetAttachedObject()->IsAsleep() &&
+				m_pConstraint->GetReferenceObject()->IsAsleep() )
+			{
+				m_soundInfo.StopThinking(this);
+				SetNextThink(TICK_NEVER_THINK);
+			}
+		}
+#endif
+	}
+
+
+#if HINGE_NOTIFY
+	virtual void OnConstraintSetup( hl_constraint_info_t &info )
+	{
+		CBaseEntity *pEntity0 = info.pObjects[0] ? static_cast<CBaseEntity *>(info.pObjects[0]->GetGameData()) : NULL;
+		if ( pEntity0 && !info.pObjects[0]->IsStatic()  )
+		{
+			WatchVPhysicsStateChanges( this, pEntity0 );
+		}
+		CBaseEntity *pEntity1 = info.pObjects[1] ? static_cast<CBaseEntity *>(info.pObjects[1]->GetGameData()) : NULL;
+		if ( pEntity1 && !info.pObjects[1]->IsStatic()  )
+		{
+			WatchVPhysicsStateChanges( this, pEntity1 );
+		}
+		BaseClass::OnConstraintSetup(info);
+	}
+
+	void SoundThink( void );
+	// void Spawn( void );
+	void Activate( void );
+	void Precache( void );
+#endif
+
+	DECLARE_DATADESC();
+
+
+#if HINGE_NOTIFY
+protected:
+	ConstraintSoundInfo m_soundInfo;
+#endif
+
+private:
+	constraint_hingeparams_t m_hinge;
+	float m_hingeFriction;
+	float	m_systemLoadScale;
+	bool IsWorldHinge( const hl_constraint_info_t &info, int *pAxisOut );
+};
+
+BEGIN_DATADESC( CPhysHinge )
+
+// Quiet down classcheck
+//	DEFINE_FIELD( m_hinge, FIELD_??? ),
+
+	DEFINE_KEYFIELD( m_hingeFriction, FIELD_FLOAT, "hingefriction" ),
+	DEFINE_FIELD( m_hinge.worldPosition, FIELD_POSITION_VECTOR ),
+	DEFINE_KEYFIELD( m_hinge.worldAxisDirection, FIELD_VECTOR, "hingeaxis" ),
+	DEFINE_KEYFIELD( m_systemLoadScale, FIELD_FLOAT, "systemloadscale" ),
+	DEFINE_INPUTFUNC( FIELD_FLOAT, "SetAngularVelocity", InputSetVelocity ),
+	DEFINE_INPUTFUNC( FIELD_FLOAT, "SetHingeFriction", InputSetHingeFriction ),
+
+#if HINGE_NOTIFY
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_THRESHOLD] , FIELD_FLOAT, "minSoundThreshold" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_FULL] , FIELD_FLOAT, "maxSoundThreshold" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundFwd, FIELD_SOUNDNAME, "slidesoundfwd" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundBack, FIELD_SOUNDNAME, "slidesoundback" ),
+
+	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[0], FIELD_SOUNDNAME, "reversalsoundSmall" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[1], FIELD_SOUNDNAME, "reversalsoundMedium" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[2], FIELD_SOUNDNAME, "reversalsoundLarge" ),
+
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[0] , FIELD_FLOAT, "reversalsoundthresholdSmall" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[1], FIELD_FLOAT, "reversalsoundthresholdMedium" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[2] , FIELD_FLOAT, "reversalsoundthresholdLarge" ),
+
+	DEFINE_THINKFUNC( SoundThink ),
+#endif
+
+END_DATADESC()
+
+
+LINK_ENTITY_TO_CLASS( phys_hinge, CPhysHinge );
+
+
+void CPhysHinge::Spawn( void )
+{
+	m_hinge.worldPosition = GetLocalOrigin();
+	m_hinge.worldAxisDirection -= GetLocalOrigin();
+	VectorNormalize(m_hinge.worldAxisDirection);
+	UTIL_SnapDirectionToAxis( m_hinge.worldAxisDirection );
+
+	m_hinge.hingeAxis.SetAxisFriction( 0, 0, 0 );
+
+	if ( HasSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY ) )
+	{
+		masscenteroverride_t params;
+		if ( m_nameAttach1 == NULL_STRING )
+		{
+			params.SnapToAxis( m_nameAttach2, m_hinge.worldPosition, m_hinge.worldAxisDirection );
+			PhysSetMassCenterOverride( params );
+		}
+		else if ( m_nameAttach2 == NULL_STRING )
+		{
+			params.SnapToAxis( m_nameAttach1, m_hinge.worldPosition, m_hinge.worldAxisDirection );
+			PhysSetMassCenterOverride( params );
+		}
+		else
+		{
+			RemoveSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY );
+		}
+	}
+
+	Precache();
+}
+
+#if HINGE_NOTIFY
+void CPhysHinge::Activate( void )
+{
+	BaseClass::Activate();
+
+	m_soundInfo.OnActivate(this);
+	if (m_pConstraint)
+	{
+		m_soundInfo.StartThinking(this, 
+			VelocitySampler::GetRelativeAngularVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()) ,
+			m_hinge.worldAxisDirection
+			);
+
+		SetThink(&CPhysHinge::SoundThink);
+		SetNextThink( gpGlobals->curtime + m_soundInfo.getThinkRate() );
+	}
+}
+
+void CPhysHinge::Precache( void )
+{
+	BaseClass::Precache();
+	return m_soundInfo.OnPrecache(this);
+}
+
+#endif
+
+
+static int GetUnitAxisIndex( const Vector &axis )
+{
+	bool valid = false;
+	int index = -1;
+
+	for ( int i = 0; i < 3; i++ )
+	{
+		if ( axis[i] != 0 )
+		{
+			if ( fabs(axis[i]) == 1 )
+			{
+				if ( index  < 0 )
+				{
+					index = i;
+					valid = true;
+					continue;
+				}
+			}
+			valid = false;
+		}
+	}
+	return valid ? index : -1;
+}
+
+bool CPhysHinge::IsWorldHinge( const hl_constraint_info_t &info, int *pAxisOut )
+{
+	if ( HasSpawnFlags( SF_CONSTRAINT_ASSUME_WORLD_GEOMETRY ) && info.pObjects[0] == g_PhysWorldObject )
+	{
+		Vector localHinge;
+		info.pObjects[1]->WorldToLocalVector( &localHinge, m_hinge.worldAxisDirection );
+		UTIL_SnapDirectionToAxis( localHinge );
+		int hingeAxis = GetUnitAxisIndex( localHinge );
+		if ( hingeAxis >= 0 )
+		{
+			*pAxisOut = hingeAxis;
+			return true;
+		}
+	}
+	return false;
+}
+
+
+#if HINGE_NOTIFY
+void CPhysHinge::SoundThink( void )
+{
+	Assert(m_pConstraint);
+	if (!m_pConstraint)
+		return;
+
+	IPhysicsObject * pAttached = m_pConstraint->GetAttachedObject(), *pReference = m_pConstraint->GetReferenceObject();
+	Assert( pAttached && pReference );
+	if (pAttached && pReference)
+	{
+		Vector relativeVel = VelocitySampler::GetRelativeAngularVelocity(pAttached,pReference);
+		if (g_debug_constraint_sounds.GetBool())
+		{
+			NDebugOverlay::Line( GetAbsOrigin(), GetAbsOrigin() + (relativeVel), 255, 255, 0, true, 0.1f );
+		}
+		m_soundInfo.OnThink( this, relativeVel );
+
+		SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());
+	}
+}
+#endif
+
+class CPhysBallSocket : public CPhysConstraint
+{
+public:
+	DECLARE_CLASS( CPhysBallSocket, CPhysConstraint );
+
+	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+	{
+		constraint_ballsocketparams_t ballsocket;
+	
+		ballsocket.Defaults();
+		
+		for ( int i = 0; i < 2; i++ )
+		{
+			info.pObjects[i]->WorldToLocal( &ballsocket.constraintPosition[i], GetAbsOrigin() );
+		}
+		GetBreakParams( ballsocket.constraint, info );
+		ballsocket.constraint.torqueLimit = 0;
+
+		return physenv->CreateBallsocketConstraint( info.pObjects[0], info.pObjects[1], pGroup, ballsocket );
+	}
+};
+
+LINK_ENTITY_TO_CLASS( phys_ballsocket, CPhysBallSocket );
+
+class CPhysSlideConstraint : public CPhysConstraint, public IVPhysicsWatcher
+{
+public:
+	DECLARE_CLASS( CPhysSlideConstraint, CPhysConstraint );
+
+	DECLARE_DATADESC();
+	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );
+	void InputSetVelocity( inputdata_t &inputdata )
+	{
+		if ( !m_pConstraint || !m_pConstraint->GetReferenceObject() || !m_pConstraint->GetAttachedObject() )
+			return;
+
+		float speed = inputdata.value.Float();
+		float massLoad = 1;
+		int numMasses = 0;
+		if ( m_pConstraint->GetReferenceObject()->IsMoveable() )
+		{
+			massLoad = m_pConstraint->GetReferenceObject()->GetMass();
+			numMasses++;
+			m_pConstraint->GetReferenceObject()->Wake();
+		}
+		if ( m_pConstraint->GetAttachedObject()->IsMoveable() )
+		{
+			massLoad += m_pConstraint->GetAttachedObject()->GetMass();
+			numMasses++;
+			m_pConstraint->GetAttachedObject()->Wake();
+		}
+		if ( numMasses > 0 )
+		{
+			massLoad /= (float)numMasses;
+		}
+		float loadscale = m_systemLoadScale != 0 ? m_systemLoadScale : 1;
+		m_pConstraint->SetLinearMotor( speed, speed * loadscale * massLoad * (1.0/TICK_INTERVAL) );
+	}
+
+	void DrawDebugGeometryOverlays()
+	{
+		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )
+		{
+			NDebugOverlay::Box( GetAbsOrigin(), -Vector(8,8,8), Vector(8,8,8), 0, 255, 0, 0, 0 );
+			NDebugOverlay::Box( m_axisEnd, -Vector(4,4,4), Vector(4,4,4), 0, 0, 255, 0, 0 );
+			NDebugOverlay::Line( GetAbsOrigin(), m_axisEnd, 255, 255, 0, false, 0 );
+		}
+		BaseClass::DrawDebugGeometryOverlays();
+	}
+
+	void NotifyVPhysicsStateChanged( IPhysicsObject *pPhysics, CBaseEntity *pEntity, bool bAwake )
+	{
+#if HINGE_NOTIFY
+		Assert(m_pConstraint);
+		if (!m_pConstraint) 
+			return;
+
+		// if something woke up, start thinking. If everything is asleep, stop thinking.
+		if ( bAwake )
+		{
+			// Did something wake up when I was not thinking?
+			if ( GetNextThink() == TICK_NEVER_THINK )
+			{
+				Vector axisDirection = m_axisEnd - GetAbsOrigin();
+				VectorNormalize( axisDirection );
+				UTIL_SnapDirectionToAxis( axisDirection );
+
+				m_soundInfo.StartThinking(this, 
+					VelocitySampler::GetRelativeVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()),
+					axisDirection
+					);
+				SetThink(&CPhysSlideConstraint::SoundThink);
+				SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());
+			}
+		}
+		else
+		{
+			// Is everything asleep? If so, stop thinking.
+			if ( GetNextThink() != TICK_NEVER_THINK				&&
+				 m_pConstraint->GetAttachedObject()->IsAsleep() &&
+				 m_pConstraint->GetReferenceObject()->IsAsleep() )
+			{
+				m_soundInfo.StopThinking(this);
+				SetNextThink(TICK_NEVER_THINK);
+			}
+		}
+#endif
+	}
+
+
+#if HINGE_NOTIFY
+	virtual void OnConstraintSetup( hl_constraint_info_t &info )
+	{
+		CBaseEntity *pEntity0 = info.pObjects[0] ? static_cast<CBaseEntity *>(info.pObjects[0]->GetGameData()) : NULL;
+		if ( pEntity0 && !info.pObjects[0]->IsStatic()  )
+		{
+			WatchVPhysicsStateChanges( this, pEntity0 );
+		}
+		CBaseEntity *pEntity1 = info.pObjects[1] ? static_cast<CBaseEntity *>(info.pObjects[1]->GetGameData()) : NULL;
+		if ( pEntity1 && !info.pObjects[1]->IsStatic()  )
+		{
+			WatchVPhysicsStateChanges( this, pEntity1 );
+		}
+		BaseClass::OnConstraintSetup(info);
+	}
+
+
+	void SoundThink( void );
+	// void Spawn( void );
+	void Activate( void );
+	void Precache( void );
+#endif
+
+	Vector	m_axisEnd;
+	float	m_slideFriction;
+	float	m_systemLoadScale;
+
+#if HINGE_NOTIFY
+protected:
+	ConstraintSoundInfo m_soundInfo;
+#endif
+};
+
+LINK_ENTITY_TO_CLASS( phys_slideconstraint, CPhysSlideConstraint );
+
+BEGIN_DATADESC( CPhysSlideConstraint )
+
+	DEFINE_KEYFIELD( m_axisEnd, FIELD_POSITION_VECTOR, "slideaxis" ),
+	DEFINE_KEYFIELD( m_slideFriction, FIELD_FLOAT, "slidefriction" ),
+	DEFINE_KEYFIELD( m_systemLoadScale, FIELD_FLOAT, "systemloadscale" ),
+	DEFINE_INPUTFUNC( FIELD_FLOAT, "SetVelocity", InputSetVelocity ),
+#if HINGE_NOTIFY
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_THRESHOLD] , FIELD_FLOAT, "minSoundThreshold" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_keyPoints[SimpleConstraintSoundProfile::kMIN_FULL] , FIELD_FLOAT, "maxSoundThreshold" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundFwd, FIELD_SOUNDNAME, "slidesoundfwd" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszTravelSoundBack, FIELD_SOUNDNAME, "slidesoundback" ),
+
+	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[0], FIELD_SOUNDNAME, "reversalsoundSmall" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[1], FIELD_SOUNDNAME, "reversalsoundMedium" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_iszReversalSounds[2], FIELD_SOUNDNAME, "reversalsoundLarge" ),
+
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[0] , FIELD_FLOAT, "reversalsoundthresholdSmall" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[1], FIELD_FLOAT, "reversalsoundthresholdMedium" ),
+	DEFINE_KEYFIELD( m_soundInfo.m_soundProfile.m_reversalSoundThresholds[2] , FIELD_FLOAT, "reversalsoundthresholdLarge" ),
+
+
+	DEFINE_THINKFUNC( SoundThink ),
+#endif
+
+END_DATADESC()
+
+
+
+IPhysicsConstraint *CPhysSlideConstraint::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+{
+	constraint_slidingparams_t sliding;
+	sliding.Defaults();
+	GetBreakParams( sliding.constraint, info );
+	sliding.constraint.strength = 1.0;
+
+	Vector axisDirection = m_axisEnd - GetAbsOrigin();
+	VectorNormalize( axisDirection );
+	UTIL_SnapDirectionToAxis( axisDirection );
+
+	sliding.InitWithCurrentObjectState( info.pObjects[0], info.pObjects[1], axisDirection );
+	sliding.friction = m_slideFriction;
+	if ( m_spawnflags & SF_SLIDE_LIMIT_ENDS )
+	{
+		Vector position;
+		info.pObjects[1]->GetPosition( &position, NULL );
+
+		sliding.limitMin = DotProduct( axisDirection, GetAbsOrigin() );
+		sliding.limitMax = DotProduct( axisDirection, m_axisEnd );
+		if ( sliding.limitMax < sliding.limitMin )
+		{
+			::V_swap( sliding.limitMin, sliding.limitMax );
+		}
+
+		// expand limits to make initial position of the attached object valid
+		float limit = DotProduct( position, axisDirection );
+		if ( limit < sliding.limitMin )
+		{
+			sliding.limitMin = limit;
+		}
+		else if ( limit > sliding.limitMax )
+		{
+			sliding.limitMax = limit;
+		}
+		// offset so that the current position is 0
+		sliding.limitMin -= limit;
+		sliding.limitMax -= limit;
+	}
+
+	return physenv->CreateSlidingConstraint( info.pObjects[0], info.pObjects[1], pGroup, sliding );
+}
+
+
+#if HINGE_NOTIFY
+void CPhysSlideConstraint::SoundThink( void )
+{
+	Assert(m_pConstraint);
+	if (!m_pConstraint)
+		return;
+
+	IPhysicsObject * pAttached = m_pConstraint->GetAttachedObject(), *pReference = m_pConstraint->GetReferenceObject();
+	Assert( pAttached && pReference );
+	if (pAttached && pReference)
+	{
+		Vector relativeVel = VelocitySampler::GetRelativeVelocity(pAttached,pReference);
+		// project velocity onto my primary axis.:
+
+		Vector axisDirection = m_axisEnd - GetAbsOrigin();
+		relativeVel = m_axisEnd * relativeVel.Dot(m_axisEnd)/m_axisEnd.Dot(m_axisEnd);
+
+		m_soundInfo.OnThink( this, relativeVel );
+
+		SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());
+	}
+
+}
+
+void CPhysSlideConstraint::Activate( void )
+{
+	BaseClass::Activate();
+
+	m_soundInfo.OnActivate(this);
+
+	Vector axisDirection = m_axisEnd - GetAbsOrigin();
+	VectorNormalize( axisDirection );
+	UTIL_SnapDirectionToAxis( axisDirection );
+	m_soundInfo.StartThinking(this, 
+		VelocitySampler::GetRelativeVelocity(m_pConstraint->GetAttachedObject(), m_pConstraint->GetReferenceObject()),
+		axisDirection
+		);
+
+	SetThink(&CPhysSlideConstraint::SoundThink);
+	SetNextThink(gpGlobals->curtime + m_soundInfo.getThinkRate());
+}
+
+void CPhysSlideConstraint::Precache()
+{
+	m_soundInfo.OnPrecache(this);
+}
+
+#endif
+
+
+
+LINK_ENTITY_TO_CLASS( phys_constraint, CPhysFixed );
+
+//-----------------------------------------------------------------------------
+// Purpose: Activate/create the constraint
+//-----------------------------------------------------------------------------
+IPhysicsConstraint *CPhysFixed::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+{
+	constraint_fixedparams_t fixed;
+	fixed.Defaults();
+	fixed.InitWithCurrentObjectState( info.pObjects[0], info.pObjects[1] );
+	GetBreakParams( fixed.constraint, info );
+
+	// constraining to the world means object 1 is fixed
+	if ( info.pObjects[0] == g_PhysWorldObject )
+	{
+		PhysSetGameFlags( info.pObjects[1], FVPHYSICS_CONSTRAINT_STATIC );
+	}
+
+	return physenv->CreateFixedConstraint( info.pObjects[0], info.pObjects[1], pGroup, fixed );
+}
+
+
+//-----------------------------------------------------------------------------
+// Purpose: Breakable pulley w/ropes constraint
+//-----------------------------------------------------------------------------
+class CPhysPulley : public CPhysConstraint
+{
+	DECLARE_CLASS( CPhysPulley, CPhysConstraint );
+public:
+	DECLARE_DATADESC();
+
+	void DrawDebugGeometryOverlays()
+	{
+		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )
+		{
+			Vector origin = GetAbsOrigin();
+			Vector refPos = origin, attachPos = origin;
+			IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();
+			if ( pRef )
+			{
+				matrix3x4_t matrix;
+				pRef->GetPositionMatrix( &matrix );
+				VectorTransform( m_offset[0], matrix, refPos );
+			}
+			IPhysicsObject *pAttach = m_pConstraint->GetAttachedObject();
+			if ( pAttach )
+			{
+				matrix3x4_t matrix;
+				pAttach->GetPositionMatrix( &matrix );
+				VectorTransform( m_offset[1], matrix, attachPos );
+			}
+			NDebugOverlay::Line( refPos, origin, 0, 255, 0, false, 0 );
+			NDebugOverlay::Line( origin, m_position2, 128, 128, 128, false, 0 );
+			NDebugOverlay::Line( m_position2, attachPos, 0, 255, 0, false, 0 );
+			NDebugOverlay::Box( origin, -Vector(8,8,8), Vector(8,8,8), 128, 255, 128, 32, 0 );
+			NDebugOverlay::Box( m_position2, -Vector(8,8,8), Vector(8,8,8), 255, 128, 128, 32, 0 );
+		}
+		BaseClass::DrawDebugGeometryOverlays();
+	}
+
+	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );
+
+private:
+	Vector		m_position2;
+	Vector		m_offset[2];
+	float		m_addLength;
+	float		m_gearRatio;
+};
+
+BEGIN_DATADESC( CPhysPulley )
+
+	DEFINE_KEYFIELD( m_position2, FIELD_POSITION_VECTOR, "position2" ),
+	DEFINE_AUTO_ARRAY( m_offset, FIELD_VECTOR ),
+	DEFINE_KEYFIELD( m_addLength, FIELD_FLOAT, "addlength" ),
+	DEFINE_KEYFIELD( m_gearRatio, FIELD_FLOAT, "gearratio" ),
+
+END_DATADESC()
+
+
+LINK_ENTITY_TO_CLASS( phys_pulleyconstraint, CPhysPulley );
+
+
+//-----------------------------------------------------------------------------
+// Purpose: Activate/create the constraint
+//-----------------------------------------------------------------------------
+IPhysicsConstraint *CPhysPulley::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+{
+	constraint_pulleyparams_t pulley;
+	pulley.Defaults();
+	pulley.pulleyPosition[0] = GetAbsOrigin();
+	pulley.pulleyPosition[1] = m_position2;
+
+	matrix3x4_t matrix;
+	Vector world[2];
+
+	info.pObjects[0]->GetPositionMatrix( &matrix );
+	VectorTransform( info.anchorPosition[0], matrix, world[0] );
+	info.pObjects[1]->GetPositionMatrix( &matrix );
+	VectorTransform( info.anchorPosition[1], matrix, world[1] );
+
+	for ( int i = 0; i < 2; i++ )
+	{
+		pulley.objectPosition[i] = info.anchorPosition[i];
+		m_offset[i] = info.anchorPosition[i];
+	}
+	
+	pulley.totalLength = m_addLength + 
+		(world[0] - pulley.pulleyPosition[0]).Length() + 
+		((world[1] - pulley.pulleyPosition[1]).Length() * m_gearRatio);
+
+	if ( m_gearRatio != 0 )
+	{
+		pulley.gearRatio = m_gearRatio;
+	}
+	GetBreakParams( pulley.constraint, info );
+	if ( m_spawnflags & SF_PULLEY_RIGID )
+	{
+		pulley.isRigid = true;
+	}
+
+	return physenv->CreatePulleyConstraint( info.pObjects[0], info.pObjects[1], pGroup, pulley );
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: Breakable rope/length constraint
+//-----------------------------------------------------------------------------
+class CPhysLength : public CPhysConstraint
+{
+	DECLARE_CLASS( CPhysLength, CPhysConstraint );
+public:
+	DECLARE_DATADESC();
+
+	void DrawDebugGeometryOverlays()
+	{
+		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )
+		{
+			Vector origin = GetAbsOrigin();
+			Vector refPos = origin, attachPos = origin;
+			IPhysicsObject *pRef = m_pConstraint->GetReferenceObject();
+			if ( pRef )
+			{
+				matrix3x4_t matrix;
+				pRef->GetPositionMatrix( &matrix );
+				VectorTransform( m_offset[0], matrix, refPos );
+			}
+			IPhysicsObject *pAttach = m_pConstraint->GetAttachedObject();
+			if ( pAttach )
+			{
+				matrix3x4_t matrix;
+				pAttach->GetPositionMatrix( &matrix );
+				VectorTransform( m_offset[1], matrix, attachPos );
+			}
+			Vector dir = attachPos - refPos;
+
+			float len = VectorNormalize(dir);
+			if ( len > m_totalLength )
+			{
+				Vector mid = refPos + dir * m_totalLength;
+				NDebugOverlay::Line( refPos, mid, 0, 255, 0, false, 0 );
+				NDebugOverlay::Line( mid, attachPos, 255, 0, 0, false, 0 );
+			}
+			else
+			{
+				NDebugOverlay::Line( refPos, attachPos, 0, 255, 0, false, 0 );
+			}
+		}
+		BaseClass::DrawDebugGeometryOverlays();
+	}
+
+	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );
+
+private:
+	Vector		m_offset[2];
+	Vector		m_vecAttach;
+	float		m_addLength;
+	float		m_minLength;
+	float		m_totalLength;
+};
+
+BEGIN_DATADESC( CPhysLength )
+
+	DEFINE_AUTO_ARRAY( m_offset, FIELD_VECTOR ),
+	DEFINE_KEYFIELD( m_addLength, FIELD_FLOAT, "addlength" ),
+	DEFINE_KEYFIELD( m_minLength, FIELD_FLOAT, "minlength" ),
+	DEFINE_KEYFIELD( m_vecAttach, FIELD_POSITION_VECTOR, "attachpoint" ),
+	DEFINE_FIELD( m_totalLength, FIELD_FLOAT ),
+END_DATADESC()
+
+
+LINK_ENTITY_TO_CLASS( phys_lengthconstraint, CPhysLength );
+
+
+//-----------------------------------------------------------------------------
+// Purpose: Activate/create the constraint
+//-----------------------------------------------------------------------------
+IPhysicsConstraint *CPhysLength::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+{
+	constraint_lengthparams_t length;
+	length.Defaults();
+	Vector position[2];
+	position[0] = GetAbsOrigin();
+	position[1] = m_vecAttach;
+	int index = info.swapped ? 1 : 0;
+	length.InitWorldspace( info.pObjects[0], info.pObjects[1], position[index], position[!index] );
+	length.totalLength += m_addLength;
+	length.minLength = m_minLength;
+	m_totalLength = length.totalLength;
+	if ( HasSpawnFlags(SF_LENGTH_RIGID) )
+	{
+		length.minLength = length.totalLength;
+	}
+
+	for ( int i = 0; i < 2; i++ )
+	{
+		m_offset[i] = length.objectPosition[i];
+	}
+	GetBreakParams( length.constraint, info );
+
+	return physenv->CreateLengthConstraint( info.pObjects[0], info.pObjects[1], pGroup, length );
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: Limited ballsocket constraint with toggle-able translation constraints
+//-----------------------------------------------------------------------------
+class CRagdollConstraint : public CPhysConstraint
+{
+	DECLARE_CLASS( CRagdollConstraint, CPhysConstraint );
+public:
+	DECLARE_DATADESC();
+#if 0
+	void DrawDebugGeometryOverlays()
+	{
+		if ( m_debugOverlays & (OVERLAY_BBOX_BIT|OVERLAY_PIVOT_BIT|OVERLAY_ABSBOX_BIT) )
+		{
+			NDebugOverlay::Line( refPos, attachPos, 0, 255, 0, false, 0 );
+		}
+		BaseClass::DrawDebugGeometryOverlays();
+	}
+#endif
+
+	IPhysicsConstraint *CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info );
+
+private:
+	float		m_xmin;	// constraint limits in degrees
+	float		m_xmax;
+	float		m_ymin;
+	float		m_ymax;
+	float		m_zmin;
+	float		m_zmax;
+
+	float		m_xfriction;
+	float		m_yfriction;
+	float		m_zfriction;
+};
+
+BEGIN_DATADESC( CRagdollConstraint )
+
+	DEFINE_KEYFIELD( m_xmin, FIELD_FLOAT, "xmin" ),
+	DEFINE_KEYFIELD( m_xmax, FIELD_FLOAT, "xmax" ),
+	DEFINE_KEYFIELD( m_ymin, FIELD_FLOAT, "ymin" ),
+	DEFINE_KEYFIELD( m_ymax, FIELD_FLOAT, "ymax" ),
+	DEFINE_KEYFIELD( m_zmin, FIELD_FLOAT, "zmin" ),
+	DEFINE_KEYFIELD( m_zmax, FIELD_FLOAT, "zmax" ),
+	DEFINE_KEYFIELD( m_xfriction, FIELD_FLOAT, "xfriction" ),
+	DEFINE_KEYFIELD( m_yfriction, FIELD_FLOAT, "yfriction" ),
+	DEFINE_KEYFIELD( m_zfriction, FIELD_FLOAT, "zfriction" ),
+
+END_DATADESC()
+
+
+LINK_ENTITY_TO_CLASS( phys_ragdollconstraint, CRagdollConstraint );
+
+//-----------------------------------------------------------------------------
+// Purpose: Activate/create the constraint
+//-----------------------------------------------------------------------------
+IPhysicsConstraint *CRagdollConstraint::CreateConstraint( IPhysicsConstraintGroup *pGroup, const hl_constraint_info_t &info )
+{
+	constraint_ragdollparams_t ragdoll;
+	ragdoll.Defaults();
+
+	matrix3x4_t entityToWorld, worldToEntity;
+	info.pObjects[0]->GetPositionMatrix( &entityToWorld );
+	MatrixInvert( entityToWorld, worldToEntity );
+	ConcatTransforms( worldToEntity, EntityToWorldTransform(), ragdoll.constraintToReference );
+
+	info.pObjects[1]->GetPositionMatrix( &entityToWorld );
+	MatrixInvert( entityToWorld, worldToEntity );
+	ConcatTransforms( worldToEntity, EntityToWorldTransform(), ragdoll.constraintToAttached );
+
+	ragdoll.onlyAngularLimits = HasSpawnFlags( SF_RAGDOLL_FREEMOVEMENT ) ? true : false;
+
+	// FIXME: Why are these friction numbers in different units from what the hinge uses?
+	ragdoll.axes[0].SetAxisFriction( m_xmin, m_xmax, m_xfriction );
+	ragdoll.axes[1].SetAxisFriction( m_ymin, m_ymax, m_yfriction );
+	ragdoll.axes[2].SetAxisFriction( m_zmin, m_zmax, m_zfriction );
+
+	if ( HasSpawnFlags( SF_CONSTRAINT_START_INACTIVE ) )
+	{
+		ragdoll.isActive = false;
+	}
+	return physenv->CreateRagdollConstraint( info.pObjects[0], info.pObjects[1], pGroup, ragdoll );
+}
+
+
+
+class CPhysConstraintEvents : public IPhysicsConstraintEvent
+{
+	void ConstraintBroken( IPhysicsConstraint *pConstraint )
+	{
+		CBaseEntity *pEntity = (CBaseEntity *)pConstraint->GetGameData();
+		if ( pEntity )
+		{
+			IPhysicsConstraintEvent *pConstraintEvent = dynamic_cast<IPhysicsConstraintEvent*>( pEntity );
+			//Msg("Constraint broken %s\n", pEntity->GetDebugName() );
+			if ( pConstraintEvent )
+			{
+				pConstraintEvent->ConstraintBroken( pConstraint );
+			}
+			else
+			{
+				variant_t emptyVariant;
+				pEntity->AcceptInput( "ConstraintBroken", NULL, NULL, emptyVariant, 0 );
+			}
+		}
+	}
+};
+
+static CPhysConstraintEvents constraintevents;
+// registered in physics.cpp
+IPhysicsConstraintEvent *g_pConstraintEvents = &constraintevents;
+
+
+
+
+
+#if HINGE_NOTIFY
+//-----------------------------------------------------------------------------
+// Code for sampler
+//-----------------------------------------------------------------------------
+
+
+/// Call this in spawn(). (Not a constructor because those are difficult to use in entities.)
+void VelocitySampler::Initialize(float samplerate)
+{
+	m_fIdealSampleRate = samplerate;
+}
+
+// This is an old style approach to reversal sounds, from when there was only one.
+#if 0
+bool VelocitySampler::HasReversed(const Vector &relativeVelocity, float thresholdAcceleration)
+{
+	// first, make sure the velocity has reversed (is more than 90deg off) from last time, or is zero now.
+	// float rVsq = relativeVelocity.LengthSqr();
+	float vDot = relativeVelocity.Dot(m_prevSample);
+	if (vDot <= 0) // there is a reversal in direction. compute the magnitude of acceleration.
+	{
+		// find the scalar projection of the relative acceleration this fame onto the previous frame's
+		// velocity, and compare that to the threshold. 
+		Vector accel = relativeVelocity - m_prevSample;
+
+		float prevSampleLength = m_prevSample.Length();
+		float projection = 0;
+		// divide through by dt to get the accel per sec
+		if (prevSampleLength)
+		{
+			projection = -(accel.Dot(m_prevSample) / prevSampleLength) / (gpGlobals->curtime - m_fPrevSampleTime);
+		}
+		else
+		{
+			projection = accel.Length() / (gpGlobals->curtime - m_fPrevSampleTime);
+		}
+
+		if (g_debug_constraint_sounds.GetBool())
+		{
+			Msg("Reversal accel is %f/%f\n",projection,thresholdAcceleration);
+		}
+		return ((projection) > thresholdAcceleration); // the scalar projection is negative because the acceleration is against vel
+	}
+	else
+	{
+		return false;
+	}
+}
+#endif
+
+/// Looks at the force of reversal and compares it to a ladder of thresholds.
+/// Returns the index of the highest threshold exceeded by the reversal velocity. 
+int VelocitySampler::HasReversed(const Vector &relativeVelocity, const float thresholdAcceleration[], const unsigned short numThresholds)
+{
+	// first, make sure the velocity has reversed (is more than 90deg off) from last time, or is zero now.
+	// float rVsq = relativeVelocity.LengthSqr();
+	float vDot = relativeVelocity.Dot(m_prevSample);
+	if (vDot <= 0) // there is a reversal in direction. compute the magnitude of acceleration.
+	{
+		// find the scalar projection of the relative acceleration this fame onto the previous frame's
+		// velocity, and compare that to the threshold. 
+		Vector accel = relativeVelocity - m_prevSample;
+
+		float prevSampleLength = m_prevSample.Length();
+		float projection = 0;
+		// divide through by dt to get the accel per sec
+		if (prevSampleLength)
+		{
+			// the scalar projection is negative because the acceleration is against vel
+			projection = -(accel.Dot(m_prevSample) / prevSampleLength) / (gpGlobals->curtime - m_fPrevSampleTime);
+		}
+		else
+		{
+			projection = accel.Length() / (gpGlobals->curtime - m_fPrevSampleTime);
+		}
+
+		if (g_debug_constraint_sounds.GetBool())
+		{
+			Msg("Reversal accel is %f/%f\n", projection, thresholdAcceleration[0]);
+		}
+
+
+		// now find the threshold crossed.
+		int retval;
+		for (retval = numThresholds - 1; retval >= 0 ; --retval)
+		{
+			if (projection > thresholdAcceleration[retval])
+				break;
+		}
+
+		return retval; 
+	}
+	else
+	{
+		return -1;
+	}
+}
+
+/// small helper function used just below (technique copy-pasted  from sound.cpp)
+inline static bool IsEmpty (const string_t &str)
+{
+	return (!str || strlen(str.ToCStr()) < 1 );
+}
+
+void ConstraintSoundInfo::OnActivate( CPhysConstraint *pOuter )
+{
+	m_pTravelSound = NULL;
+	m_vSampler.Initialize( getThinkRate() );
+
+
+	ValidateInternals( pOuter );
+
+	// make sure sound filenames are not empty 
+	m_bPlayTravelSound   = !IsEmpty(m_iszTravelSoundFwd) || !IsEmpty(m_iszTravelSoundBack);
+	m_bPlayReversalSound = false;
+	for (int i = 0; i < SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE ; ++i)
+	{
+		if ( !IsEmpty(m_iszReversalSounds[i]) )
+		{
+			// if there is at least one filled sound field, we should try
+			// to play reversals
+			m_bPlayReversalSound = true;
+			break;
+		}
+	}
+
+
+	/*
+	SetThink(&CPhysSlideConstraint::SoundThink);
+	SetNextThink(gpGlobals->curtime + m_vSampler.getSampleRate());
+	*/
+}
+
+/// Maintain consistency of internal datastructures on start
+void ConstraintSoundInfo::ValidateInternals( CPhysConstraint *pOuter )
+{
+	// Make sure the reversal sound thresholds are strictly increasing.
+	for (int i = 1 ; i < SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE ; ++i)
+	{
+		// if decreases from small to medium, promote small to medium and warn.
+		if (m_soundProfile.m_reversalSoundThresholds[i] < m_soundProfile.m_reversalSoundThresholds[i-1])
+		{
+			Warning("Constraint reversal sounds for %s are out of order!", pOuter->GetDebugName() );
+			m_soundProfile.m_reversalSoundThresholds[i] = m_soundProfile.m_reversalSoundThresholds[i-1];
+			m_iszReversalSounds[i] = m_iszReversalSounds[i-1];
+		}
+	}
+}
+
+void ConstraintSoundInfo::OnPrecache( CPhysConstraint *pOuter )
+{
+	pOuter->PrecacheScriptSound( m_iszTravelSoundFwd.ToCStr() ); 
+	pOuter->PrecacheScriptSound( m_iszTravelSoundBack.ToCStr() ); 
+	for (int i = 0 ; i < SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE; ++i )
+	{
+		pOuter->PrecacheScriptSound( m_iszReversalSounds[i].ToCStr() );
+	}
+}
+
+void ConstraintSoundInfo::OnThink( CPhysConstraint *pOuter, const Vector &relativeVelocity )
+{
+	// have we had a hard reversal?
+	int playReversal = m_vSampler.HasReversed( relativeVelocity, m_soundProfile.m_reversalSoundThresholds, SimpleConstraintSoundProfile::kREVERSAL_SOUND_ARRAY_SIZE );
+	float relativeVelMag = relativeVelocity.Length(); //< magnitude of relative velocity
+
+	CBaseEntity *pChildEntity = static_cast<CBaseEntity *>(pOuter->GetPhysConstraint()->GetAttachedObject()->GetGameData());
+
+	// compute sound level
+	float soundVol = this->m_soundProfile.GetVolume(relativeVelMag);
+
+	if (g_debug_constraint_sounds.GetBool())
+	{
+		char tempstr[512];
+		Q_snprintf(tempstr,sizeof(tempstr),"Velocity: %.3f", relativeVelMag );
+		pChildEntity->EntityText( 0, tempstr, m_vSampler.getSampleRate() );
+
+		Q_snprintf(tempstr,sizeof(tempstr),"Sound volume: %.3f", soundVol );
+		pChildEntity->EntityText( 1, tempstr, m_vSampler.getSampleRate() );
+
+		if (playReversal >= 0)
+		{
+			Q_snprintf(tempstr,sizeof(tempstr),"Reversal [%d]", playReversal );
+			pChildEntity->EntityText(2,tempstr,m_vSampler.getSampleRate());
+		}
+	}
+
+	// if we loaded a travel sound
+	if (m_bPlayTravelSound)
+	{
+		if (soundVol > 0)
+		{
+			// if we want to play a sound...
+			if ( m_pTravelSound )
+			{	// if a sound exists, modify it
+				CSoundEnvelopeController::GetController().SoundChangeVolume( m_pTravelSound, soundVol, 0.1f );
+			}
+			else
+			{	// if a sound does not exist, create it
+				bool travellingForward = relativeVelocity.Dot(m_forwardAxis) > 0;
+
+				CSoundEnvelopeController &controller = CSoundEnvelopeController::GetController();
+				CPASAttenuationFilter filter( pChildEntity );
+				m_pTravelSound = controller.SoundCreate( filter, pChildEntity->entindex(), 
+					(travellingForward ? m_iszTravelSoundFwd : m_iszTravelSoundBack).ToCStr() );
+				controller.Play( m_pTravelSound, soundVol, 100 );
+			}
+		}
+		else
+		{
+			// if we want to not play sound
+			if ( m_pTravelSound )
+			{	// and it exists, kill it
+				CSoundEnvelopeController::GetController().SoundDestroy( m_pTravelSound );
+				m_pTravelSound = NULL;
+			}
+		}
+	}
+
+	if (m_bPlayReversalSound && (playReversal >= 0))
+	{
+		pChildEntity->EmitSound(m_iszReversalSounds[playReversal].ToCStr());
+	}
+
+	m_vSampler.AddSample( relativeVelocity );
+	
+}
+
+
+void ConstraintSoundInfo::StartThinking( CPhysConstraint *pOuter, const Vector &relativeVelocity, const Vector &forwardVector )
+{
+	m_forwardAxis = forwardVector;
+	m_vSampler.BeginSampling( relativeVelocity );
+
+	/*
+	IPhysicsConstraint *pConstraint = pOuter->GetPhysConstraint();
+	Assert(pConstraint);
+	if (pConstraint)
+	{
+		IPhysicsObject * pAttached = pConstraint->GetAttachedObject(), *pReference = pConstraint->GetReferenceObject();
+		m_vSampler.BeginSampling( VelocitySampler::GetRelativeVelocity(pAttached,pReference) );
+	}
+	*/
+}
+
+void ConstraintSoundInfo::StopThinking( CPhysConstraint *pOuter )
+{
+	DeleteAllSounds();
+}
+
+
+ConstraintSoundInfo::~ConstraintSoundInfo()
+{
+	DeleteAllSounds();
+}
+
+// Any sounds envelopes that are active, kill.
+void ConstraintSoundInfo::DeleteAllSounds()
+{
+	if ( m_pTravelSound )
+	{
+		CSoundEnvelopeController::GetController().SoundDestroy( m_pTravelSound );
+		m_pTravelSound = NULL;
+	}
+}
+
+#endif