Heron

An ergonomic physics API for 2d and 3d [bevy] games. (powered by [rapier])

Design principles

• Don't mirror rapier's API and don't expect users to know how [rapier] works.
  • [rapier]'s API targets physics simulation for rust, where Heron targets [bevy] games. It is "similar", yes, but it isn't "the same".
  • When designing the API, only usage in [bevy] games matters. How the rapier's API looks like doesn't matter.
• Use [bevy] types, resources and components when possible (Vec3, Quat, Transform, Events, etc.)
• Provide a single API that works for both 2d and 3d. (Like bevy does)
• Data oriented. Using this library should look like it is part of [bevy].
• Avoid asking the user to lookup in resources via handles. Data should be accessible and modifiable directly in components.
• Hide the actual physics engine. This is an implementation detail the user shouldn't have to care about.
  • But, allow advanced users to access the underlying [rapier] resources, so a user is never blocked by a missing element in the API of heron.

Features

One must choose to use either 2d or 3d (but not both). If none of theses two features is enabled, the PhysicsPlugin won't be available.

Enabled by Default

• 3d Enable simulation on the 3 axes x, y, and z. Incompatible with the feature 2d.

Optional

• 2d Enable simulation only on the first 2 axes x and y. Incompatible with the feature 3d, therefore require to disable the default features.
• debug Render collision shapes. Works only in 2d, support for 3d will be added later.

Motivation

I think [rapier] is very powerful as a physics engine. But using it directly or via [bevy_rapier] in a [bevy] game is not ergonomic enough for my taste.

Ideally I would like to have the power of [rapier] accessible behind a an API focused on [bevy] games.