关于Farseer的使用链接：http://www.farseergames.com/storage/farseerphysics/Manual2.1.htm
0. FixedDistanceJoint
1. DistanceJoint 两个body的中心距离
2. FixedRevoluteJoint
3. RevoluteJoint 一个Dynamic body ,一个static body,
4 FixedPrismaticJoint
5. PrismaticJoint
if we attached a dynamic body to a static body with a prismatic joint then we can slide it along an axis (similar to the moving levels in a platformer). If we attached a dynamic body to another dynamic body, then you will notice that both boxes rotate relative to each other.
6.PulleyJoint
As the name suggests it is used for creating a pulley system. You can specify a ratio of how far one side changes compared to the other. The pulley does take a bit of tweaking to get it set up correctly for how you want it to function.
7.GearJoint
A gear could be created by making a body in the shape of a gear and applying a motor, but a gear joint will be much more efficient and simpler to set up. Gear joints are created by using a mixture of either revolute or prismatic joints connected to a static body. As one body changes it subsequently affects the other body. Note, that in the initialization function the static body must be the first parameter .
8. LineJoint
If you are wanting to create a suspension for a model of a car then the line joint is what you will be after. It was created specifically for this purpose. It is like the prismatic joint but with the rotation restriction removed. For example, a wheel can slide along an axis (the shock absorber) while rotating. The spring portion of the shock absorber can be modelled by creating friction using the motor
9. WeldJoint
The weld joint allows us to weld two bodies together. Pretty simple. If you are wanting to use it for setting up breakable structures then you should take note of the Box2D manual comment “It is tempting to use the weld joint to define breakable structures. However, the Box2D solver is iterative so the joints are a bit soft. So chains of bodies connected by weld joints will flex. Instead it is better to create breakable bodies starting with a single body with multiple fixtures. When the body breaks, you can destroy a fixture and recreate it on a new body.”
10. SliderJoint
11. FixedFrictionJoint
12. FixedFrictionJoint
13. FixedAngleJoint
14. AngleJoint