1 files changed, 114 insertions, 0 deletions
diff --git a/src/libjin/3rdparty/Box2D/Dynamics/Joints/b2RopeJoint.h b/src/libjin/3rdparty/Box2D/Dynamics/Joints/b2RopeJoint.h
new file mode 100644
index 0000000..ef5d6f7
--- /dev/null
+++ b/src/libjin/3rdparty/Box2D/Dynamics/Joints/b2RopeJoint.h
@@ -0,0 +1,114 @@
+/*
+* 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.
+*/
+
+#ifndef B2_ROPE_JOINT_H
+#define B2_ROPE_JOINT_H
+
+#include "Box2D/Dynamics/Joints/b2Joint.h"
+
+/// Rope joint definition. This requires two body anchor points and
+/// a maximum lengths.
+/// Note: by default the connected objects will not collide.
+/// see collideConnected in b2JointDef.
+struct b2RopeJointDef : public b2JointDef
+{
+	b2RopeJointDef()
+	{
+		type = e_ropeJoint;
+		localAnchorA.Set(-1.0f, 0.0f);
+		localAnchorB.Set(1.0f, 0.0f);
+		maxLength = 0.0f;
+	}
+
+	/// The local anchor point relative to bodyA's origin.
+	b2Vec2 localAnchorA;
+
+	/// The local anchor point relative to bodyB's origin.
+	b2Vec2 localAnchorB;
+
+	/// The maximum length of the rope.
+	/// Warning: this must be larger than b2_linearSlop or
+	/// the joint will have no effect.
+	float32 maxLength;
+};
+
+/// A rope joint enforces a maximum distance between two points
+/// on two bodies. It has no other effect.
+/// Warning: if you attempt to change the maximum length during
+/// the simulation you will get some non-physical behavior.
+/// A model that would allow you to dynamically modify the length
+/// would have some sponginess, so I chose not to implement it
+/// that way. See b2DistanceJoint if you want to dynamically
+/// control length.
+class b2RopeJoint : public b2Joint
+{
+public:
+	b2Vec2 GetAnchorA() const override;
+	b2Vec2 GetAnchorB() const override;
+
+	b2Vec2 GetReactionForce(float32 inv_dt) const override;
+	float32 GetReactionTorque(float32 inv_dt) const override;
+
+	/// The local anchor point relative to bodyA's origin.
+	const b2Vec2& GetLocalAnchorA() const { return m_localAnchorA; }
+
+	/// The local anchor point relative to bodyB's origin.
+	const b2Vec2& GetLocalAnchorB() const  { return m_localAnchorB; }
+
+	/// Set/Get the maximum length of the rope.
+	void SetMaxLength(float32 length) { m_maxLength = length; }
+	float32 GetMaxLength() const;
+
+	b2LimitState GetLimitState() const;
+
+	/// Dump joint to dmLog
+	void Dump() override;
+
+protected:
+
+	friend class b2Joint;
+	b2RopeJoint(const b2RopeJointDef* data);
+
+	void InitVelocityConstraints(const b2SolverData& data) override;
+	void SolveVelocityConstraints(const b2SolverData& data) override;
+	bool SolvePositionConstraints(const b2SolverData& data) override;
+
+	// Solver shared
+	b2Vec2 m_localAnchorA;
+	b2Vec2 m_localAnchorB;
+	float32 m_maxLength;
+	float32 m_length;
+	float32 m_impulse;
+
+	// Solver temp
+	int32 m_indexA;
+	int32 m_indexB;
+	b2Vec2 m_u;
+	b2Vec2 m_rA;
+	b2Vec2 m_rB;
+	b2Vec2 m_localCenterA;
+	b2Vec2 m_localCenterB;
+	float32 m_invMassA;
+	float32 m_invMassB;
+	float32 m_invIA;
+	float32 m_invIB;
+	float32 m_mass;
+	b2LimitState m_state;
+};
+
+#endif