In Unity, force can be applied to objects using the `AddForce` function or the `AddRelativeForce` function.
While both functions serve a similar purpose, there are some key differences between them that you should be aware of. In this article, we will explore the contrast between `AddForce` and `AddRelativeForce`, and discuss their strengths and weaknesses in various scenarios.
What is AddForce?
`AddForce` is a function that allows you to apply a force to an object at a specific point in space. The force can be of any magnitude and direction, and can be used to move or rotate the object.
For example, if you want to make a car accelerate forward, you would use `AddForce` on the car’s rigidbody component to apply a force in that direction.
What is AddRelativeForce?
`AddRelativeForce` is similar to `AddForce`, but instead of applying a force relative to the world origin, it applies the force relative to the object’s current position. This means that if you use `AddRelativeForce` on an object that has already been moved, the force will be applied relative to its new position, rather than the world origin.
For example, if you want to make a car accelerate forward while it is already moving, you would use `AddRelativeForce` on the car’s rigidbody component to apply a force in that direction relative to the car’s current position.
Contrast between AddForce and AddRelativeForce
One of the main differences between `AddForce` and `AddRelativeForce` is where the force is applied from. `AddForce` applies the force relative to the world origin, while `AddRelativeForce` applies the force relative to the object’s current position.
For example, if you use `AddForce` on an object that is standing still, it will start moving in the direction of the force. However, if you use `AddRelativeForce` on the same object while it is already moving, it will continue to move in the same direction at the same speed, but it will now be affected by any external forces that were previously ignored.
Another difference between `AddForce` and `AddRelativeForce` is how they affect objects with rigidbody components. When you use `AddForce` on an object with a rigidbody component, Unity applies a force to the rigidbody, but it doesn’t affect any other objects in the scene. However, when you use `AddRelativeForce`, Unity applies a force to the rigidbody relative to its current position, which can cause it to collide with other objects in the scene.
Strengths and Weaknesses of AddForce
One strength of `AddForce` is that it allows you to apply a force to an object at any point in space, making it easy to create realistic physics simulations.
However, one weakness of `AddForce` is that it can be difficult to predict the exact effect of the force on the object, especially if there are many other objects in the scene with rigidbody components.
Strengths and Weaknesses of AddRelativeForce
One strength of `AddRelativeForce` is that it allows you to apply a force to an object relative to its current position, which can be useful for creating realistic physics simulations when objects are moving or colliding with each other.
However, one weakness of `AddRelativeForce` is that it can be difficult to control the exact effect of the force on the object, especially if there are many other objects in the scene with rigidbody components.