3.0以后最Box2d和chipmunk这两个物理引擎进行了封装，使用起来非常的便利。
offset：重心点
velocity：速度
dadamping：阻尼
rerestitution：弹力
mamaterial：材质
mass：质量
moment：力矩，当他碰到另一个刚体时候 ，会产生一股扭转力，做旋转运动
body：刚体，表示物理世界中的抽象实体，附带有物理属性
shape：刚体的形状，同一个body可以附加多个shape 该shape们不会发生碰撞
joint：关节，可以连接>=2个刚体
1.physicsBody
001.
/** 创建一个body mass和moment为默认值 */
002.
staticPhysicsBody* create();
003.
/** 创建一个质量为mass的body moment为默认值. */
004.
PhysicsBody* create(floatmass);
005.
/** 创建一个body 并为mass 和moment赋值 */
006.
mass,moment);
007.
/**创建一个shape为圆形的body */
008.
PhysicsBody* createCircle(radius,宋体">constPhysicsMaterial& material = PHYSICSBODY_MATERIAL_DEFAULT,宋体">Point& offset = Point::ZERO);
009.
/** 创建一个shape为四边形的body. */
010.
PhysicsBody* createBox(Size& size,92)">011.
/**创建一个动态多边形刚体，多边形的顶点存放在Point array[ ]中 示例：Point array[ ]={ point(1,1),point(2,2)} 注意：顶点必须按顺时针存放，并且图形为凸状，不能是凹的*/
012.
PhysicsBody* createPolygon(Point* points,宋体">intcount,92)">013.
014.
/** 创建一个静态的线状刚体. */
015.
PhysicsBody* createEdgeSegment(Point& a,宋体">Point& b,宋体">border =1);
016.
/** 创建一个静态四边形刚体. */
017.
PhysicsBody* createEdgeBox(,宋体">Point& offset = Point::ZERO);
018.
/** 创建一个静态多边形刚体. */
019.
PhysicsBody* createEdgePolygon(020.
/** 创建一个链条状刚体 */
021.
PhysicsBody* createEdgeChain(022.
023.
/*
024.
添加一个shape mass和moment赋值true
025.
*/
026.
virtual PhysicsShape* addShape(PhysicsShape* shape,bool addMassAndMoment =true);
027.
/*通过shape移除shape*/
028.
voidremoveShape(PhysicsShape* shape,bool reduceMassAndMoment =029.
/*通过tag移除shape*/
030.
removeShape(tag,92)">031.
/* 移除body的所有shape */
032.
removeAllShapes(bool reduceMassAndMoment =033.
/* 获取body的shapes */
034.
inlineVector<PhysicsShape*>& getShapes(){return_shapes; }
035.
/* 获取第一个shape. */
036.
inline PhysicsShape* getFirstShape()_shapes.size() >=? _shapes.at(0) : nullptr; }
037.
/* 通过tag从body中获取shape */
038.
PhysicsShape* getShape(tag);
039.
040.
/**给body施加一个循序渐进的力，物体会受加速度影响，越来越快，像火车一样*/
041.
virtualapplyForce(Vect& force);
042.
/** offset为偏移度 指碰到物体时 body旋转 偏移 一般设为默认值 值越大 旋转越快 偏移角度越大*/
043.
Vect& force,宋体">Point& offset);
044.
/** 重置施加在body上的力 清0了. */
045.
resetForces();
046.
/** 不会产生力，直接与body的速度叠加 产生新的速度. */
047.
applyImpulse(Vect& impulse);
048.
/** Applies a continuous force to body. */
049.
Vect& impulse,92)">050.
/**施加一个扭转力到刚体上 就像向前翻转一块大石头一样. */
051.
applyTorque(torque);
052.
053.
/** 设置刚体的速度*/
054.
setVelocity(Vect& velocity);
055.
/** 获取刚体的速度 */
056.
virtual Point getVelocity();
057.
/** 设置刚体角速度 就是单位时间内转动的弧度*/
058.
setAngularVelocity(velocity);
059.
/** 通过一个局部点获取刚体的角速度*/
060.
virtual Point getVelocityAtLocalPoint(Point& point);
061.
/** 通过世界点获取刚体的角速度*/
062.
virtual Point getVelocityAtWorldPoint(063.
/** 获取刚体的角速度 */
064.
getAngularVelocity();
065.
/** 设置速度的极限值*/
066.
setVelocityLimit(limit);
067.
/**获取速度的极限值 */
068.
getVelocityLimit();
069.
/** 设置角速度极限值 */
070.
getAngularVelocityLimit();
071.
072.
/** 从world中移除body */
073.
removeFromWorld();
074.
075.
/** 获取world */
076.
inline PhysicsWorld* getWorld()_world; }
077.
/**获取body的所有关节 */
078.
std::vector<PhysicsJoint*>& getJoints()_joints; }
079.
080.
/** 取得body设置的sprite. */
081.
inline Node* getNode()_node; }
082.
083.
/**
084.
* A mask that defines which categories this physics body belongs to.
085.
* Every physics body in a scene can be assigned to up to 32 different categories,each corresponding to a bit in the bit mask. You define the mask values used in your game. In conjunction with the collisionBitMask and contactTestBitMask properties,you define which physics bodies interact with each other and when your game is notified of these interactions.
086.
* The default value is 0xFFFFFFFF (all bits set).
087.
*/没搞懂
088.
setCategoryBitmask(bitmask);
089.
090.
* A mask that defines which categories of bodies cause intersection notifications with this physics body.
091.
* When two bodies share the same space,each body’s category mask is tested against the other body’s contact mask by performing a logical AND operation. If either comparison results in a non-zero value,an PhysicsContact object is created and passed to the physics world’s delegate. For best performance,only set bits in the contacts mask for interactions you are interested in.
092.
* The default value is 0x00000000 (all bits cleared).
093.
094.
setContactTestBitmask(095.
096.
* A mask that defines which categories of physics bodies can collide with this physics body.
097.
* When two physics bodies contact each other,a collision may occur. This body’s collision mask is compared to the other body’s category mask by performing a logical AND operation. If the result is a non-zero value,then this body is affected by the collision. Each body independently chooses whether it wants to be affected by the other body. For example,you might use this to avoid collision calculations that would make negligible changes to a body’s velocity.
098.
099.
100.
setCollisionBitmask(101.
/** get the category bit mask */
102.
getCategoryBitmask()_categoryBitmask; }
103.
/** get the contact test bit mask */
104.
getContactTestBitmask()_contactTestBitmask; }
105.
/** get the collision bit mask */
106.
getCollisionBitmask()_collisionBitmask; }
107.
108.
/**
109.
* set the group of body
110.
* Collision groups let you specify an integral group index. You can have all fixtures with the same group index always collide (positive index) or never collide (negative index)
111.
* it have high priority than bit masks
112.
*/
113.
setGroup(group);
114.
/** get the group of body */
115.
getGroup()_group; }
116.
117.
/** 获取body坐标 */
118.
Point getPosition()119.
/** 获取body角度. */
120.
getRotation()121.
122.
/**判断body是否静止*/
123.
inline bool isDynamic()_dynamic; }
124.
/**设置body状态 false为静态 true为动态*/
125.
setDynamic(bool dynamic);
128.
setMass(129.
/** 取得mass. */
130.
getMass()_mass; }
131.
132.
* @brief add mass to body.
133.
* if _mass(mass of the body) == PHYSICS_INFINITY,it remains.
134.
* if mass == PHYSICS_INFINITY,_mass will be PHYSICS_INFINITY.
135.
* if mass == -PHYSICS_INFINITY,_mass will not change.
136.
* if mass + _mass <= 0,_mass will equal to MASS_DEFAULT(1.0)
137.
* other wise,mass = mass + _mass;
138.
增加质量
139.
addMass(mass);
140.
141.
142.
* @brief set the body moment of inertia.
143.
* @note if you need add/subtract moment to body,don't use setMoment(getMoment() +/- moment),because the moment of body may be equal to PHYSICS_INFINITY,it will cause some unexpected result,please use addMoment() instead.
144.
设置力矩
145.
setMoment(moment);
146.
/** 获取惯性的力矩. */
147.
getMoment(moment)_moment; }
148.
149.
* @brief add moment of inertia to body.
150.
* if _moment(moment of the body) == PHYSICS_INFINITY,it remains.
151.
* if moment == PHYSICS_INFINITY,_moment will be PHYSICS_INFINITY.
152.
* if moment == -PHYSICS_INFINITY,_moment will not change.
153.
* if moment + _moment <= 0,_moment will equal to MASS_DEFAULT(1.0)
154.
155.
增加力矩
156.
addMoment(157.
/** 取得线性阻尼 */
158.
getLinearDamping()_linearDamping; }
159.
160.
* 设置阻尼值
161.
*它用来模拟body在气体或者液体中的摩擦力
162.
*取值范围是 0.0f to 1.0f.
163.
164.
setLinearDamping(damping) { _linearDamping = damping; }
165.
/** 获取角阻尼 */
166.
getAngularDamping()_angularDamping; }
167.
168.
* 设置角阻尼
169.
* 它用来模拟body在气体或者液体中的角阻尼
170.
* the value is 0.0f to 1.0f.
171.
172.
setAngularDamping(damping) { _angularDamping = damping; }
173.
174.
/** 判断body是否是 休息状态 */
175.
bool isResting();
176.
177.
*判断body能否在物理世界中模拟
178.
179.
inline bool isEnabled()_enable; }
180.
181.
设置body能否在物理世界中模拟
182.
183.
setEnable(bool enable);
184.
185.
/** whether the body can rotation */
186.
inline bool isRotationEnabled()_rotationEnable; }
187.
/**设置能否旋转*/
188.
setRotationEnable(bool enable);
189.
190.
/** 判断body是否受引力影响 */
191.
inline bool isGravityEnabled()_gravityEnable; }
192.
/** 设置body是否受引力影响 */
193.
setGravityEnable(bool enable);
194.
195.
/** 取得body 的tag值 */
196.
getTag()_tag; }
197.
/** 设置body tag值*/
198.
setTag(tag) { _tag = tag; }
199.
200.
/** 转换 世界点 到 局部点 类似 世界坐标和 局部坐标的转换*/
201.
Point world2Local(Point& point);
202.
/** 转换局部坐标到 世界坐标 */
203.
Point local2World(Point& point);
2.PhysicsShape
01.
/** 通过shape 取得body */
02.
inline PhysicsBody* getBody()_body; }
03.
/** 返回shape的类型 */
04.
inline Type getType()_type; }
05.
/** 返回shape的面积 */
06.
getArea()_area; }
07.
/** 取得moment 力矩 */
08.
getMoment()_moment; }
09.
/** Set moment,it will change the body's moment this shape attaches */
10.
moment);//设置力矩
11.
tag) { _tag = tag; }//设置标签tag
12.
_tag; }//取得tag标签
13.
14.
/**获取质量 */
15.
_mass; }
16.
/** Set mass,it will change the body's mass this shape attaches */
17.
mass);//设置质量
18.
getDensity()_material.density; }//density为密度
19.
setDensity(density);//获取密度
20.
getRestitution()_material.restitution; }//获取弹性
21.
setRestitution(restitution);//设置弹性
22.
getFriction()_material.friction; }//friction为摩擦力
23.
setFriction(friction);//设置摩擦力
24.
PhysicsMaterial& getMaterial()_material; }//Material为材质
25.
setMaterial(PhysicsMaterial& material);设置材质
26.
27.
/** 返回默认力矩 其值为0 */
28.
calculateDefaultMoment() {return.0f; }
29.
/** 取得重心 初始值为zero */
30.
virtual Point getOffset() {Point::ZERO; }
31.
/** 获取shape的重心点 */
32.
virtual Point getCenter() {getOffset(); }
33.
/**shape是否包含该点 */
34.
bool containsPoint(Point& point)35.
36.
/** 改变重心点 */
37.
staticrecenterPoints(Point* points,宋体">Point& center = Point::ZERO);
38.
/** 取得多边形的重心点 */
39.
Point getPolyonCenter(count);
40.
41.
42.
43.
44.
45.
46.
bitmask) { _categoryBitmask = bitmask; }
47.
_categoryBitmask; }
48.
49.
* A mask that defines which categories of bodies cause intersection notifications with this physics body.
50.
51.
* The default value is 0x00000000 (all bits cleared).
52.
53.
bitmask) { _contactTestBitmask = bitmask; }
54.
55.
56.
57.
58.
59.
60.
bitmask) { _collisionBitmask = bitmask; }
61.
_collisionBitmask; }
62.
63.
64.
getGroup() {_group; }
