> For the complete documentation index, see [llms.txt](https://unfinishedstudios1.gitbook.io/fp-motion/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://unfinishedstudios1.gitbook.io/fp-motion/components/motion-effects/bob.md).

# Bob

> To bob is to make a quick, short movement up and down.

## Description

This motion effect recreates the position changes in the walking animations that a lot of first-person games have for their camera and guns.

## How does it work?

Every frame a `sin()` function is used to calculate what the position of the object should be, the result is **combined** with the player’s movement and the [Wave Data](/fp-motion/data/wave-data.md) that the developer sets to produce the final effect.

## Tweaking the effect

To change the effect that this component produces, you can change the `wave` value, this field contains the [Wave Data ](/fp-motion/data/wave-data.md)used to change the effect.

{% hint style="info" %}
The [State Data](/fp-motion/data/state-data.md) for the player’s current state has a multiplier for this effect.
{% endhint %}