Box2D: /build/box2d/src/box2d-2.4.1/include/box2d/b2_mouse_joint.h Source File

| Box2D 2.4.1 A 2D physics engine for games

b2_mouse_joint.h
1 // MIT License
2
3 // Copyright (c) 2019 Erin Catto
4
5 // Permission is hereby granted, free of charge, to any person obtaining a copy
6 // of this software and associated documentation files (the "Software"), to deal
7 // in the Software without restriction, including without limitation the rights
8 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9 // copies of the Software, and to permit persons to whom the Software is
10 // furnished to do so, subject to the following conditions:
11
12 // The above copyright notice and this permission notice shall be included in all
13 // copies or substantial portions of the Software.
14
15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 // SOFTWARE.
22
23 #ifndef B2_MOUSE_JOINT_H
24 #define B2_MOUSE_JOINT_H
25
26 #include "b2_api.h"
27 #include "b2_joint.h"
28
31 struct B2_API b2MouseJointDef : public b2JointDef
32 {
33 b2MouseJointDef()
34 {
35 type = e_mouseJoint;
36 target.Set(0.0f, 0.0f);
37 maxForce = 0.0f;
38 stiffness = 0.0f;
39 damping = 0.0f;
40 }
41
44 b2Vec2 target;
45
49 float maxForce;
50
52 float stiffness;
53
55 float damping;
56 };
57
65 class B2_API b2MouseJoint : public b2Joint
66 {
67 public:
68
70 b2Vec2 GetAnchorA() const override;
71
73 b2Vec2 GetAnchorB() const override;
74
76 b2Vec2 GetReactionForce(float inv_dt) const override;
77
79 float GetReactionTorque(float inv_dt) const override;
80
82 void SetTarget(const b2Vec2& target);
83 const b2Vec2& GetTarget() const;
84
86 void SetMaxForce(float force);
87 float GetMaxForce() const;
88
90 void SetStiffness(float stiffness) { m_stiffness = stiffness; }
91 float GetStiffness() const { return m_stiffness; }
92
94 void SetDamping(float damping) { m_damping = damping; }
95 float GetDamping() const { return m_damping; }
96
98 void Dump() override { b2Log("Mouse joint dumping is not supported.\n"); }
99
101 void ShiftOrigin(const b2Vec2& newOrigin) override;
102
103 protected:
104 friend class b2Joint;
105
106 b2MouseJoint(const b2MouseJointDef* def);
107
108 void InitVelocityConstraints(const b2SolverData& data) override;
109 void SolveVelocityConstraints(const b2SolverData& data) override;
110 bool SolvePositionConstraints(const b2SolverData& data) override;
111
112 b2Vec2 m_localAnchorB;
113 b2Vec2 m_targetA;
114 float m_stiffness;
115 float m_damping;
116 float m_beta;
117
118 // Solver shared
119 b2Vec2 m_impulse;
120 float m_maxForce;
121 float m_gamma;
122
123 // Solver temp
124 int32 m_indexA;
125 int32 m_indexB;
126 b2Vec2 m_rB;
127 b2Vec2 m_localCenterB;
128 float m_invMassB;
129 float m_invIB;
130 b2Mat22 m_mass;
131 b2Vec2 m_C;
132 };
133
134 #endif
b2Vec2
A 2D column vector.
Definition: b2_math.h:42
b2MouseJoint::GetAnchorB
b2Vec2 GetAnchorB() const override
Implements b2Joint.
b2MouseJoint::ShiftOrigin
void ShiftOrigin(const b2Vec2 &newOrigin) override
Implement b2Joint::ShiftOrigin.
b2Log
void b2Log(const char *string,...)
Implement this to use your own logging.
Definition: b2_settings.h:115
b2JointDef
Joint definitions are used to construct joints.
Definition: b2_joint.h:73
b2MouseJointDef::target
b2Vec2 target
Definition: b2_mouse_joint.h:44
b2MouseJoint::SetStiffness
void SetStiffness(float stiffness)
Set/get the linear stiffness in N/m.
Definition: b2_mouse_joint.h:90
b2MouseJoint::SetTarget
void SetTarget(const b2Vec2 &target)
Use this to update the target point.
b2MouseJoint::SetMaxForce
void SetMaxForce(float force)
Set/get the maximum force in Newtons.
b2MouseJoint::SetDamping
void SetDamping(float damping)
Set/get linear damping in N*s/m.
Definition: b2_mouse_joint.h:94
b2MouseJoint::Dump
void Dump() override
The mouse joint does not support dumping.
Definition: b2_mouse_joint.h:98
b2MouseJoint::GetReactionForce
b2Vec2 GetReactionForce(float inv_dt) const override
Implements b2Joint.
b2MouseJoint::GetReactionTorque
float GetReactionTorque(float inv_dt) const override
Implements b2Joint.
b2Mat22
A 2-by-2 matrix. Stored in column-major order.
Definition: b2_math.h:172
b2SolverData
Solver Data.
Definition: b2_time_step.h:68
b2MouseJointDef
Definition: b2_mouse_joint.h:32
b2MouseJoint
Definition: b2_mouse_joint.h:66
b2MouseJointDef::maxForce
float maxForce
Definition: b2_mouse_joint.h:49
b2Joint
Definition: b2_joint.h:111
b2MouseJointDef::damping
float damping
The linear damping in N*s/m.
Definition: b2_mouse_joint.h:55
b2MouseJointDef::stiffness
float stiffness
The linear stiffness in N/m.
Definition: b2_mouse_joint.h:52
b2MouseJoint::GetAnchorA
b2Vec2 GetAnchorA() const override
Implements b2Joint.