Crate heron[−][src]
Expand description
An ergonomic physics API for 2d and 3d bevy games. (powered by rapier)
Get started
Add the dependency and choose to work with either 2d or 3d
Add the library to Cargo.toml
.
For a 3d game:
heron = { version = "0.10.1", features = ["3d"] }
For as 2d game:
heron = { version = "0.10.1", features = ["2d"] }
Feature flags
One must choose to use either 2d
or 3d
. If none of theses two features is enabled, the plugin won’t be available.
3d
Enable simulation on the 3 axesx
,y
, andz
. Incompatible with the feature2d
.2d
Enable simulation only on the first 2 axesx
andy
. Incompatible with the feature3d
, therefore require to disable the default features.debug-2d
Render 2d collision shapes. Works only in 2d, support for 3d may be added later.
Install the plugin
The PhysicsPlugin
should be installed to enable physics and collision detection.
use bevy::prelude::*; use heron::prelude::*; fn main() { App::build() .add_plugins(DefaultPlugins) .add_plugin(PhysicsPlugin::default()) // ... Add your resources and systems .run(); }
Create rigid bodies
To create a rigid body, add the RigidBody
to the entity and add a collision shapes with the
CollisionShape
component.
The position and rotation are defined by the bevy GlobalTransform
component.
fn spawn(mut commands: Commands) { commands // Spawn any bundle of your choice. Only make sure there is a `GlobalTransform` .spawn_bundle(SpriteBundle::default()) // Make it a rigid body .insert(RigidBody::Dynamic) // Attach a collision shape .insert(CollisionShape::Sphere { radius: 10.0 }) // Optionally add other useful components... .insert(Velocity::from_linear(Vec3::X * 2.0)) .insert(Acceleration::from_linear(Vec3::X * 1.0)) .insert(PhysicMaterial { friction: 1.0, density: 10.0, ..Default::default() }) .insert(RotationConstraints::lock()); }
Move rigid bodies programmatically
When creating games, it is often useful to interact with the physics engine and move bodies
programmatically. For this, you have two options: Updating the Transform
or applying a
Velocity
.
Option 1: Update the Transform
For positional kinematic bodies (RigidBody::KinematicPositionBased
), if the transform is
updated, the body is moved and get an automatically calculated velocity. Physics rules will be
applied normally. Updating the transform is a good way to move a kinematic body.
For other types of bodies, if the transform is updated, the rigid body will be teleported to the new position/rotation, ignoring physic rules.
Option 2: Use the Velocity component
For RigidBody::Dynamic
and RigidBody::KinematicVelocityBased
bodies only, one can
add a Velocity
component to the entity, that will move the body over time. Physics rules
will be applied normally.
Note that the velocity component is updated by heron to always reflects the current velocity.
Defining/updating the velocity is a good way to interact with dynamic bodies.
See also
- How to define a
RigidBody
- How to choose a
CollisionShape
- How to define the world’s
Gravity
- How to define the world’s
PhysicsTime
- How to define the
PhysicMaterial
- How to listen to
CollisionEvent
- How to define
RotationConstraints
Modules
Re-exports of the most commons/useful types
Physics behavior powered by rapier
Utility traits and extensions
Structs
Component that defines the linear and angular acceleration.
An axis-angle representation
Collision data concerning one of the two entity that collided
Components that defines the collision layers of the collision shape.
Plugin that registers stage resources and components.
Resource that defines world’s gravity.
Component that defines the physics properties of the rigid body
Plugin to install to enable collision detection and physics behavior.
Resource to control how many physics steps are performed per second.
Resource that controls the physics time scale
Component that restrict what rotations can be caused by forces.
Mark the CollisionShape
of the same entity as being a sensor.
Component that defines the linear and angular velocity.
Enums
An event fired when the collision state between two entities changed
Components that defines the collision shape of a rigid body
The duration of time that this physics step should advance the simulation time
Physics system labels
Component that mark the entity as being a rigid body
Traits
Describes a collision layer
Functions
Run criteria system that decides if the physics systems should run.