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diff --git a/ThirdParty/Box2D/Dynamics/Joints/b2DistanceJoint.cpp b/ThirdParty/Box2D/Dynamics/Joints/b2DistanceJoint.cpp
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+++ b/ThirdParty/Box2D/Dynamics/Joints/b2DistanceJoint.cpp
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+/*
+* Copyright (c) 2006-2011 Erin Catto http://www.box2d.org
+*
+* This software is provided 'as-is', without any express or implied
+* warranty.  In no event will the authors be held liable for any damages
+* arising from the use of this software.
+* Permission is granted to anyone to use this software for any purpose,
+* including commercial applications, and to alter it and redistribute it
+* freely, subject to the following restrictions:
+* 1. The origin of this software must not be misrepresented; you must not
+* claim that you wrote the original software. If you use this software
+* in a product, an acknowledgment in the product documentation would be
+* appreciated but is not required.
+* 2. Altered source versions must be plainly marked as such, and must not be
+* misrepresented as being the original software.
+* 3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "Box2D/Dynamics/Joints/b2DistanceJoint.h"
+#include "Box2D/Dynamics/b2Body.h"
+#include "Box2D/Dynamics/b2TimeStep.h"
+
+// 1-D constrained system
+// m (v2 - v1) = lambda
+// v2 + (beta/h) * x1 + gamma * lambda = 0, gamma has units of inverse mass.
+// x2 = x1 + h * v2
+
+// 1-D mass-damper-spring system
+// m (v2 - v1) + h * d * v2 + h * k * 
+
+// C = norm(p2 - p1) - L
+// u = (p2 - p1) / norm(p2 - p1)
+// Cdot = dot(u, v2 + cross(w2, r2) - v1 - cross(w1, r1))
+// J = [-u -cross(r1, u) u cross(r2, u)]
+// K = J * invM * JT
+//   = invMass1 + invI1 * cross(r1, u)^2 + invMass2 + invI2 * cross(r2, u)^2
+
+void b2DistanceJointDef::Initialize(b2Body* b1, b2Body* b2,
+									const b2Vec2& anchor1, const b2Vec2& anchor2)
+{
+	bodyA = b1;
+	bodyB = b2;
+	localAnchorA = bodyA->GetLocalPoint(anchor1);
+	localAnchorB = bodyB->GetLocalPoint(anchor2);
+	b2Vec2 d = anchor2 - anchor1;
+	length = d.Length();
+}
+
+b2DistanceJoint::b2DistanceJoint(const b2DistanceJointDef* def)
+: b2Joint(def)
+{
+	m_localAnchorA = def->localAnchorA;
+	m_localAnchorB = def->localAnchorB;
+	m_length = def->length;
+	m_frequencyHz = def->frequencyHz;
+	m_dampingRatio = def->dampingRatio;
+	m_impulse = 0.0f;
+	m_gamma = 0.0f;
+	m_bias = 0.0f;
+}
+
+void b2DistanceJoint::InitVelocityConstraints(const b2SolverData& data)
+{
+	m_indexA = m_bodyA->m_islandIndex;
+	m_indexB = m_bodyB->m_islandIndex;
+	m_localCenterA = m_bodyA->m_sweep.localCenter;
+	m_localCenterB = m_bodyB->m_sweep.localCenter;
+	m_invMassA = m_bodyA->m_invMass;
+	m_invMassB = m_bodyB->m_invMass;
+	m_invIA = m_bodyA->m_invI;
+	m_invIB = m_bodyB->m_invI;
+
+	b2Vec2 cA = data.positions[m_indexA].c;
+	float32 aA = data.positions[m_indexA].a;
+	b2Vec2 vA = data.velocities[m_indexA].v;
+	float32 wA = data.velocities[m_indexA].w;
+
+	b2Vec2 cB = data.positions[m_indexB].c;
+	float32 aB = data.positions[m_indexB].a;
+	b2Vec2 vB = data.velocities[m_indexB].v;
+	float32 wB = data.velocities[m_indexB].w;
+
+	b2Rot qA(aA), qB(aB);
+
+	m_rA = b2Mul(qA, m_localAnchorA - m_localCenterA);
+	m_rB = b2Mul(qB, m_localAnchorB - m_localCenterB);
+	m_u = cB + m_rB - cA - m_rA;
+
+	// Handle singularity.
+	float32 length = m_u.Length();
+	if (length > b2_linearSlop)
+	{
+		m_u *= 1.0f / length;
+	}
+	else
+	{
+		m_u.Set(0.0f, 0.0f);
+	}
+
+	float32 crAu = b2Cross(m_rA, m_u);
+	float32 crBu = b2Cross(m_rB, m_u);
+	float32 invMass = m_invMassA + m_invIA * crAu * crAu + m_invMassB + m_invIB * crBu * crBu;
+
+	// Compute the effective mass matrix.
+	m_mass = invMass != 0.0f ? 1.0f / invMass : 0.0f;
+
+	if (m_frequencyHz > 0.0f)
+	{
+		float32 C = length - m_length;
+
+		// Frequency
+		float32 omega = 2.0f * b2_pi * m_frequencyHz;
+
+		// Damping coefficient
+		float32 d = 2.0f * m_mass * m_dampingRatio * omega;
+
+		// Spring stiffness
+		float32 k = m_mass * omega * omega;
+
+		// magic formulas
+		float32 h = data.step.dt;
+		m_gamma = h * (d + h * k);
+		m_gamma = m_gamma != 0.0f ? 1.0f / m_gamma : 0.0f;
+		m_bias = C * h * k * m_gamma;
+
+		invMass += m_gamma;
+		m_mass = invMass != 0.0f ? 1.0f / invMass : 0.0f;
+	}
+	else
+	{
+		m_gamma = 0.0f;
+		m_bias = 0.0f;
+	}
+
+	if (data.step.warmStarting)
+	{
+		// Scale the impulse to support a variable time step.
+		m_impulse *= data.step.dtRatio;
+
+		b2Vec2 P = m_impulse * m_u;
+		vA -= m_invMassA * P;
+		wA -= m_invIA * b2Cross(m_rA, P);
+		vB += m_invMassB * P;
+		wB += m_invIB * b2Cross(m_rB, P);
+	}
+	else
+	{
+		m_impulse = 0.0f;
+	}
+
+	data.velocities[m_indexA].v = vA;
+	data.velocities[m_indexA].w = wA;
+	data.velocities[m_indexB].v = vB;
+	data.velocities[m_indexB].w = wB;
+}
+
+void b2DistanceJoint::SolveVelocityConstraints(const b2SolverData& data)
+{
+	b2Vec2 vA = data.velocities[m_indexA].v;
+	float32 wA = data.velocities[m_indexA].w;
+	b2Vec2 vB = data.velocities[m_indexB].v;
+	float32 wB = data.velocities[m_indexB].w;
+
+	// Cdot = dot(u, v + cross(w, r))
+	b2Vec2 vpA = vA + b2Cross(wA, m_rA);
+	b2Vec2 vpB = vB + b2Cross(wB, m_rB);
+	float32 Cdot = b2Dot(m_u, vpB - vpA);
+
+	float32 impulse = -m_mass * (Cdot + m_bias + m_gamma * m_impulse);
+	m_impulse += impulse;
+
+	b2Vec2 P = impulse * m_u;
+	vA -= m_invMassA * P;
+	wA -= m_invIA * b2Cross(m_rA, P);
+	vB += m_invMassB * P;
+	wB += m_invIB * b2Cross(m_rB, P);
+
+	data.velocities[m_indexA].v = vA;
+	data.velocities[m_indexA].w = wA;
+	data.velocities[m_indexB].v = vB;
+	data.velocities[m_indexB].w = wB;
+}
+
+bool b2DistanceJoint::SolvePositionConstraints(const b2SolverData& data)
+{
+	if (m_frequencyHz > 0.0f)
+	{
+		// There is no position correction for soft distance constraints.
+		return true;
+	}
+
+	b2Vec2 cA = data.positions[m_indexA].c;
+	float32 aA = data.positions[m_indexA].a;
+	b2Vec2 cB = data.positions[m_indexB].c;
+	float32 aB = data.positions[m_indexB].a;
+
+	b2Rot qA(aA), qB(aB);
+
+	b2Vec2 rA = b2Mul(qA, m_localAnchorA - m_localCenterA);
+	b2Vec2 rB = b2Mul(qB, m_localAnchorB - m_localCenterB);
+	b2Vec2 u = cB + rB - cA - rA;
+
+	float32 length = u.Normalize();
+	float32 C = length - m_length;
+	C = b2Clamp(C, -b2_maxLinearCorrection, b2_maxLinearCorrection);
+
+	float32 impulse = -m_mass * C;
+	b2Vec2 P = impulse * u;
+
+	cA -= m_invMassA * P;
+	aA -= m_invIA * b2Cross(rA, P);
+	cB += m_invMassB * P;
+	aB += m_invIB * b2Cross(rB, P);
+
+	data.positions[m_indexA].c = cA;
+	data.positions[m_indexA].a = aA;
+	data.positions[m_indexB].c = cB;
+	data.positions[m_indexB].a = aB;
+
+	return b2Abs(C) < b2_linearSlop;
+}
+
+b2Vec2 b2DistanceJoint::GetAnchorA() const
+{
+	return m_bodyA->GetWorldPoint(m_localAnchorA);
+}
+
+b2Vec2 b2DistanceJoint::GetAnchorB() const
+{
+	return m_bodyB->GetWorldPoint(m_localAnchorB);
+}
+
+b2Vec2 b2DistanceJoint::GetReactionForce(float32 inv_dt) const
+{
+	b2Vec2 F = (inv_dt * m_impulse) * m_u;
+	return F;
+}
+
+float32 b2DistanceJoint::GetReactionTorque(float32 inv_dt) const
+{
+	B2_NOT_USED(inv_dt);
+	return 0.0f;
+}
+
+void b2DistanceJoint::Dump()
+{
+	int32 indexA = m_bodyA->m_islandIndex;
+	int32 indexB = m_bodyB->m_islandIndex;
+
+	b2Log("  b2DistanceJointDef jd;\n");
+	b2Log("  jd.bodyA = bodies[%d];\n", indexA);
+	b2Log("  jd.bodyB = bodies[%d];\n", indexB);
+	b2Log("  jd.collideConnected = bool(%d);\n", m_collideConnected);
+	b2Log("  jd.localAnchorA.Set(%.15lef, %.15lef);\n", m_localAnchorA.x, m_localAnchorA.y);
+	b2Log("  jd.localAnchorB.Set(%.15lef, %.15lef);\n", m_localAnchorB.x, m_localAnchorB.y);
+	b2Log("  jd.length = %.15lef;\n", m_length);
+	b2Log("  jd.frequencyHz = %.15lef;\n", m_frequencyHz);
+	b2Log("  jd.dampingRatio = %.15lef;\n", m_dampingRatio);
+	b2Log("  joints[%d] = m_world->CreateJoint(&jd);\n", m_index);
+}