EZPhysics Network Protocol

EZPhysics provides a network interface for sending and receiving data from the ODE simulation. This is done through predefined packets. This page lists what these packages contain and in what order (has determined in EZNetwork class, at EZPhysicsNetwork.cpp).

An EZPhysics Network Message has the following format:

Send Packets refers to the packets sent from EZPhysics, which contain the latest simulation's data.

Usually sent in pairs, refers to the point of contact between two Body's.

1. Float X of the contact point
2. Float Y of the contact point
3. Float Z of the contact point
4. Float depth (penetration of the collision)

A Body's output.

1. Float X of the position vector
2. Float Y of the position vector
3. Float Z of the position vector
4. Float W of the rotation quaternion
5. Float X of the rotation quaternion
6. Float Y of the rotation quaternion
7. Float Z of the rotation quaternion
8. Float X of the force vector
9. Float Y of the force vector
10. Float Z of the force vector
11. Float X of the torque vector
12. Float Y of the torque vector
13. Float Z of the torque vector
14. Float Unused
15. Float X of the linear velocity vector
16. Float Y of the linear velocity vector
17. Float Z of the linear velocity vector
18. Float X of the angular velocity vector
19. Float Y of the angular velocity vector
20. Float Z of the angular velocity vector
21. Float Unused

Refers to each of the possibly several axis of a Joint.

1. Float displacement value of the axis (Relevant for the Slider Joint)
2. Float angular velocity at the axis

The feedback can be used by the user, so that it is known how much force an individual joint exerts.

1. Float X of the force vector of body 1
2. Float Y of the force vector of body 1
3. Float Z of the force vector of body 1
4. Float X of the torque vector of body 1
5. Float Y of the torque vector of body 1
6. Float Z of the torque vector of body 1
7. Float X of the force vector of body 2
8. Float Y of the force vector of body 2
9. Float Z of the force vector of body 2
10. Float X of the torque vector of body 2
11. Float Y of the torque vector of body 2
12. Float Z of the torque vector of body 2

Can be used to determine the current time of simulation.

1. Long ODE step number (since the beginning of the simulation)
2. Float ODE step size

Receive Packets refers to the packets received in EZPhysics, which contain the control commands to apply in the simulation.

Commands the simulation to restart.

Represents a raw torque applied in an axis.

1. Float torque value to apply to the axis 1 of a Joint
2. Float torque value to apply to the axis 2 of a Joint (May be invalid)
3. Float torque value to apply to the axis 3 of a Joint (May be invalid)

Provides a common servo motor interface, target velocity and maximum torque.

1. Float target velocity to apply on axis 1 of a Joint
2. Float maximum torque imposed on axis 1 of a Joint
3. Float target velocity to apply on axis 2 of a Joint (May be invalid)
4. Float maximum torque imposed on axis 2 of a Joint (May be invalid)
5. Float target velocity to apply on axis 3 of a Joint (May be invalid)
6. Float maximum torque imposed on axis 3 of a Joint (May be invalid)