# b2MouseJointDef Struct Reference

`#include <b2MouseJoint.h>`

Inheritance diagram for b2MouseJointDef:

List of all members.

## Public Member Functions
| b2MouseJointDef ()
## Public Attributes
b2Vec2 | target
float32 | maxForce
float32 | frequencyHz
| The response speed.
float32 | dampingRatio
| The damping ratio. 0 = no damping, 1 = critical damping.

## Detailed Description

Mouse joint definition. This requires a world target point, tuning parameters, and the time step.

## Constructor & Destructor Documentation

b2MouseJointDef::b2MouseJointDef | ( |  | ) | `[inline]`

## Member Data Documentation

float32 b2MouseJointDef::dampingRatio

The damping ratio. 0 = no damping, 1 = critical damping.

float32 b2MouseJointDef::frequencyHz

The response speed.

float32 b2MouseJointDef::maxForce

The maximum constraint force that can be exerted to move the candidate body. Usually you will express as some multiple of the weight (multiplier * mass * gravity).

b2Vec2 b2MouseJointDef::target

The initial world target point. This is assumed to coincide with the body anchor initially.

The documentation for this struct was generated from the following file:

- Box2D/Box2D/Dynamics/Joints/b2MouseJoint.h