aframe-physics-extras

Add-on components for the aframe-physics-system to add additional collision detection and behavior control options.

• physics-collider

• collision-filter

• sleepy

physics-collider

A collision detection component powered by the physics simulation with low overhead and precise collision zones. This is intended to be placed on tracked controller entities to monitor collisions and report them to a gesture interpretation component such as super-hands.

API

| Property | Description | Default Value | | -------- | ----------- | ------------- | | ignoreSleep | Wake sleeping bodies on collision? | true | physics-collider can also report collisions with static bodies when ignoreSleep is true. This can be useful to create collision detection zones for interactivity with things other than dynamic bodies.

Events

| Type | Description | Detail object | | --- | --- | --- | | collisions | Emitted each tick if there are changes to the collision list | els: array of new collisions. cleardEls: array of collisions which have ended. |

collision-filter

Control which physics bodies interact with each other or ignore each other. This can improve physics system performance by skipping unnecessary collision checks. It also controls which entities can be interacted with via physics-collider

API

| Property | Description | Default Value | | -------- | ----------- | ------------- | | group | Collision group this entity belongs to | 'default' | | collidesWith | Array of collision groups this entity will interact with | 'default' | | collisionForces | Should other bodies react to collisions with this body? | true | collisionForces controls whether collisions with this body generate any forces. Setting this to false allows for collisions to be registered and tracked without causing any corresponding movement. This is useful for your controller entities with physics-collider because it is difficult to pick things up if they are constantly bumped away when your hand gets close. This can be toggles through events with a controller button press if you want to be able to bump other objects sometimes and reach inside to pick them up other times. There is an example of this on the examples page. Turning off collisionForces can also be useful for setting static bodies as collision zones to detect the presence of other entities without disturbing them.

sleepy

Make entities settle down and be still after physics collisions. Very useful for zero-gravity user interfaces to keep entities from floating away. Also can help performance as sleeping bodies are handled efficiently by the physics simulation.

API

| Property | Description | Default Value | | -------- | ----------- | ------------- | | allowSleep | Enable sleep for this body | true | | speedLimit | Maximum velocity for sleep to initiate | 0.25 | | delay | Time interval to check for sleep initiation (seconds) | 0.25 | | linearDamping | Deceleration of liner forces on the entity (0 to 1) | 0.99 | | angularDamping | Deceleration of angular forces on the entity (0 to 1) | 0.99 | | holdState | Entity state in which sleep is suspended | 'grabbed' | Adding sleepy to any body will activate sleep for the entire physics system and will affect other bodies because the cannon defaults for all bodies are to allow sleep with a speed limit of 0.1 and delay of 1 second. You can add sleepy="allowSleep: false; linearDamping: 0.01; angularDamping: 0.01" to restore default behavior to an entity if needed. Sleeping bodies will ignore static bodies (hence why physics-collider has an ignoreSleep setting) until they are woken by a dynamic or kinematic body. Sleep will break constraints, so the holdState property allows you to suspend sleep during interactions such as grabbing/carrying the entity.

Examples

View the examples page to see aframe-physics-extras in action.

Installation

Browser

Install and use by directly including the browser files: ```html My A-Frame Scene

<a-assets>

<a-mixin id="controller"

physics-collider

static-body="shape: sphere; sphereRadius: 0.02"

super-hands="colliderEvent: collisions;

colliderEventProperty: els;

colliderEndEvent: collisions;

colliderEndEventProperty: clearedEls"

collision-filter = "group: hands;

collidesWith: red, blue;

collisionForces: false">

</a-mixin>

<a-mixin id="cube" dynamic-body grabbable

geometry="primitive: box; width: 0.5; height: 0.5; depth: 0.5">

</a-mixin>

</a-assets>

<!-- settings pulled in from controller mixin above -->

<a-entity hand-controls="left" mixin="controller"></a-entity>

<a-entity hand-controls="right" mixin="controller"></a-entity>

<!-- can be picked up because it collides with the hands group and vice versa -->

<a-entity mixin="cube" position="0 1.6 -1" material="color: red" sleepy

collision-filter="group: red; collidesWith: default, hands, blue">

</a-entity>

<!-- even though the controller has blue in its collidesWith list,

since the blue cube doesn't also have hands in its list, you cannot

pick it up, but you can knock it around with the red cube -->

<a-entity mixin="cube" position="0 1 -1" material="color: blue" sleepy

collision-filter="group: blue; collidesWith: default, red">

</a-entity>

<!-- floor entity. 'default' collision group so cubes will bounce off -->

<a-box width="20" depth="20" height="0.1" static-body

collision-filter="collidesWith: red, blue"

material="color: #7BC8A4"></a-box>

```

npm

Install via npm: ```bash npm install ``` Then require and use. ```js require('aframe'); require('aframe-physics-system') require('aframe-physics-extras'); ```