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diff --git a/ThirdParty/Box2D/Dynamics/Joints/b2WeldJoint.cpp b/ThirdParty/Box2D/Dynamics/Joints/b2WeldJoint.cpp
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+++ b/ThirdParty/Box2D/Dynamics/Joints/b2WeldJoint.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/b2WeldJoint.h"
+#include "Box2D/Dynamics/b2Body.h"
+#include "Box2D/Dynamics/b2TimeStep.h"
+
+// Point-to-point constraint
+// C = p2 - p1
+// Cdot = v2 - v1
+//      = v2 + cross(w2, r2) - v1 - cross(w1, r1)
+// J = [-I -r1_skew I r2_skew ]
+// Identity used:
+// w k % (rx i + ry j) = w * (-ry i + rx j)
+
+// Angle constraint
+// C = angle2 - angle1 - referenceAngle
+// Cdot = w2 - w1
+// J = [0 0 -1 0 0 1]
+// K = invI1 + invI2
+
+void b2WeldJointDef::Initialize(b2Body* bA, b2Body* bB, const b2Vec2& anchor)
+{
+	bodyA = bA;
+	bodyB = bB;
+	localAnchorA = bodyA->GetLocalPoint(anchor);
+	localAnchorB = bodyB->GetLocalPoint(anchor);
+	referenceAngle = bodyB->GetAngle() - bodyA->GetAngle();
+}
+
+b2WeldJoint::b2WeldJoint(const b2WeldJointDef* def)
+: b2Joint(def)
+{
+	m_localAnchorA = def->localAnchorA;
+	m_localAnchorB = def->localAnchorB;
+	m_referenceAngle = def->referenceAngle;
+	m_frequencyHz = def->frequencyHz;
+	m_dampingRatio = def->dampingRatio;
+
+	m_impulse.SetZero();
+}
+
+void b2WeldJoint::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;
+
+	float32 aA = data.positions[m_indexA].a;
+	b2Vec2 vA = data.velocities[m_indexA].v;
+	float32 wA = data.velocities[m_indexA].w;
+
+	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);
+
+	// J = [-I -r1_skew I r2_skew]
+	//     [ 0       -1 0       1]
+	// r_skew = [-ry; rx]
+
+	// Matlab
+	// K = [ mA+r1y^2*iA+mB+r2y^2*iB,  -r1y*iA*r1x-r2y*iB*r2x,          -r1y*iA-r2y*iB]
+	//     [  -r1y*iA*r1x-r2y*iB*r2x, mA+r1x^2*iA+mB+r2x^2*iB,           r1x*iA+r2x*iB]
+	//     [          -r1y*iA-r2y*iB,           r1x*iA+r2x*iB,                   iA+iB]
+
+	float32 mA = m_invMassA, mB = m_invMassB;
+	float32 iA = m_invIA, iB = m_invIB;
+
+	b2Mat33 K;
+	K.ex.x = mA + mB + m_rA.y * m_rA.y * iA + m_rB.y * m_rB.y * iB;
+	K.ey.x = -m_rA.y * m_rA.x * iA - m_rB.y * m_rB.x * iB;
+	K.ez.x = -m_rA.y * iA - m_rB.y * iB;
+	K.ex.y = K.ey.x;
+	K.ey.y = mA + mB + m_rA.x * m_rA.x * iA + m_rB.x * m_rB.x * iB;
+	K.ez.y = m_rA.x * iA + m_rB.x * iB;
+	K.ex.z = K.ez.x;
+	K.ey.z = K.ez.y;
+	K.ez.z = iA + iB;
+
+	if (m_frequencyHz > 0.0f)
+	{
+		K.GetInverse22(&m_mass);
+
+		float32 invM = iA + iB;
+		float32 m = invM > 0.0f ? 1.0f / invM : 0.0f;
+
+		float32 C = aB - aA - m_referenceAngle;
+
+		// Frequency
+		float32 omega = 2.0f * b2_pi * m_frequencyHz;
+
+		// Damping coefficient
+		float32 d = 2.0f * m * m_dampingRatio * omega;
+
+		// Spring stiffness
+		float32 k = m * 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;
+
+		invM += m_gamma;
+		m_mass.ez.z = invM != 0.0f ? 1.0f / invM : 0.0f;
+	}
+	else if (K.ez.z == 0.0f)
+	{
+		K.GetInverse22(&m_mass);
+		m_gamma = 0.0f;
+		m_bias = 0.0f;
+	}
+	else
+	{
+		K.GetSymInverse33(&m_mass);
+		m_gamma = 0.0f;
+		m_bias = 0.0f;
+	}
+
+	if (data.step.warmStarting)
+	{
+		// Scale impulses to support a variable time step.
+		m_impulse *= data.step.dtRatio;
+
+		b2Vec2 P(m_impulse.x, m_impulse.y);
+
+		vA -= mA * P;
+		wA -= iA * (b2Cross(m_rA, P) + m_impulse.z);
+
+		vB += mB * P;
+		wB += iB * (b2Cross(m_rB, P) + m_impulse.z);
+	}
+	else
+	{
+		m_impulse.SetZero();
+	}
+
+	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 b2WeldJoint::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;
+
+	float32 mA = m_invMassA, mB = m_invMassB;
+	float32 iA = m_invIA, iB = m_invIB;
+
+	if (m_frequencyHz > 0.0f)
+	{
+		float32 Cdot2 = wB - wA;
+
+		float32 impulse2 = -m_mass.ez.z * (Cdot2 + m_bias + m_gamma * m_impulse.z);
+		m_impulse.z += impulse2;
+
+		wA -= iA * impulse2;
+		wB += iB * impulse2;
+
+		b2Vec2 Cdot1 = vB + b2Cross(wB, m_rB) - vA - b2Cross(wA, m_rA);
+
+		b2Vec2 impulse1 = -b2Mul22(m_mass, Cdot1);
+		m_impulse.x += impulse1.x;
+		m_impulse.y += impulse1.y;
+
+		b2Vec2 P = impulse1;
+
+		vA -= mA * P;
+		wA -= iA * b2Cross(m_rA, P);
+
+		vB += mB * P;
+		wB += iB * b2Cross(m_rB, P);
+	}
+	else
+	{
+		b2Vec2 Cdot1 = vB + b2Cross(wB, m_rB) - vA - b2Cross(wA, m_rA);
+		float32 Cdot2 = wB - wA;
+		b2Vec3 Cdot(Cdot1.x, Cdot1.y, Cdot2);
+
+		b2Vec3 impulse = -b2Mul(m_mass, Cdot);
+		m_impulse += impulse;
+
+		b2Vec2 P(impulse.x, impulse.y);
+
+		vA -= mA * P;
+		wA -= iA * (b2Cross(m_rA, P) + impulse.z);
+
+		vB += mB * P;
+		wB += iB * (b2Cross(m_rB, P) + impulse.z);
+	}
+
+	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 b2WeldJoint::SolvePositionConstraints(const b2SolverData& data)
+{
+	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);
+
+	float32 mA = m_invMassA, mB = m_invMassB;
+	float32 iA = m_invIA, iB = m_invIB;
+
+	b2Vec2 rA = b2Mul(qA, m_localAnchorA - m_localCenterA);
+	b2Vec2 rB = b2Mul(qB, m_localAnchorB - m_localCenterB);
+
+	float32 positionError, angularError;
+
+	b2Mat33 K;
+	K.ex.x = mA + mB + rA.y * rA.y * iA + rB.y * rB.y * iB;
+	K.ey.x = -rA.y * rA.x * iA - rB.y * rB.x * iB;
+	K.ez.x = -rA.y * iA - rB.y * iB;
+	K.ex.y = K.ey.x;
+	K.ey.y = mA + mB + rA.x * rA.x * iA + rB.x * rB.x * iB;
+	K.ez.y = rA.x * iA + rB.x * iB;
+	K.ex.z = K.ez.x;
+	K.ey.z = K.ez.y;
+	K.ez.z = iA + iB;
+
+	if (m_frequencyHz > 0.0f)
+	{
+		b2Vec2 C1 =  cB + rB - cA - rA;
+
+		positionError = C1.Length();
+		angularError = 0.0f;
+
+		b2Vec2 P = -K.Solve22(C1);
+
+		cA -= mA * P;
+		aA -= iA * b2Cross(rA, P);
+
+		cB += mB * P;
+		aB += iB * b2Cross(rB, P);
+	}
+	else
+	{
+		b2Vec2 C1 =  cB + rB - cA - rA;
+		float32 C2 = aB - aA - m_referenceAngle;
+
+		positionError = C1.Length();
+		angularError = b2Abs(C2);
+
+		b2Vec3 C(C1.x, C1.y, C2);
+	
+		b2Vec3 impulse;
+		if (K.ez.z > 0.0f)
+		{
+			impulse = -K.Solve33(C);
+		}
+		else
+		{
+			b2Vec2 impulse2 = -K.Solve22(C1);
+			impulse.Set(impulse2.x, impulse2.y, 0.0f);
+		}
+
+		b2Vec2 P(impulse.x, impulse.y);
+
+		cA -= mA * P;
+		aA -= iA * (b2Cross(rA, P) + impulse.z);
+
+		cB += mB * P;
+		aB += iB * (b2Cross(rB, P) + impulse.z);
+	}
+
+	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 positionError <= b2_linearSlop && angularError <= b2_angularSlop;
+}
+
+b2Vec2 b2WeldJoint::GetAnchorA() const
+{
+	return m_bodyA->GetWorldPoint(m_localAnchorA);
+}
+
+b2Vec2 b2WeldJoint::GetAnchorB() const
+{
+	return m_bodyB->GetWorldPoint(m_localAnchorB);
+}
+
+b2Vec2 b2WeldJoint::GetReactionForce(float32 inv_dt) const
+{
+	b2Vec2 P(m_impulse.x, m_impulse.y);
+	return inv_dt * P;
+}
+
+float32 b2WeldJoint::GetReactionTorque(float32 inv_dt) const
+{
+	return inv_dt * m_impulse.z;
+}
+
+void b2WeldJoint::Dump()
+{
+	int32 indexA = m_bodyA->m_islandIndex;
+	int32 indexB = m_bodyB->m_islandIndex;
+
+	b2Log("  b2WeldJointDef 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.referenceAngle = %.15lef;\n", m_referenceAngle);
+	b2Log("  jd.frequencyHz = %.15lef;\n", m_frequencyHz);
+	b2Log("  jd.dampingRatio = %.15lef;\n", m_dampingRatio);
+	b2Log("  joints[%d] = m_world->CreateJoint(&jd);\n", m_index);
+}