devhang / oimo.js

Lightweight 3d physics engine for javascript

Oimo.js is a lightweight 3d physics engine for JavaScript.
It's a full javascript conversion of OimoPhysics
Originally created by Saharan for actionscript 3.0.

Home

• oimo.js (in progress)

Docs

• docs (in progress)

Demo

• Basic test
• Compound test (chair)
• Compound test (capsule)
• Ragdoll test
• Collision test
• Moving test
• Terrain test
• Car test
• Walker test
• Worker test

Usage

Download the minified library and include it in your HTML.
Alternatively, use Node and install the package: npm install oimo

<script src="js/oimo.min.js"></script>

Create physics world:

world = new OIMO.World({ 
    timestep: 1/60, 
    iterations: 8, 
    broadphase: 2, // 1 brute force, 2 sweep and prune, 3 volume tree
    worldscale: 1, // scale full world 
    random: true,  // randomize sample
    info: false,   // calculate statistic or not
    gravity: [0,-9.8,0] 
});

Add physics object or joint

var body = world.add({ 
    type:'sphere', // type of shape : sphere, box, cylinder 
    size:[1,1,1], // size of shape
    pos:[0,0,0], // start position in degree
    rot:[0,0,90], // start rotation in degree
    move:true, // dynamic or statique
    density: 1,
    friction: 0.2,
    restitution: 0.2,
    belongsTo: 1, // The bits of the collision groups to which the shape belongs.
    collidesWith: 0xffffffff; // The bits of the collision groups with which the shape collides.
});

var body = world.add({ 
    type:'jointHinge', // type of joint : jointDistance, jointHinge, jointPrisme, jointSlide, jointWheel
    body1: "b1", // name or id of attach rigidbody
    body2: "b1", // name or id of attach rigidbody
});


// update world
world.step();

// and copy position and rotation to three mesh
myMesh.position.copy( body.getPosition() );
myMesh.quaternion.copy( body.getQuaternion() );

Note

Oimo Physics uses international system units: 0.1 to 10 meters max for dynamic body.
In basic demo with THREE, I scaled all by 100 so objects are between 10 to 1000 in THREE units.

/!\ Shape name change in last version
SphereShape to Sphere, BoxShape to Box, CylinderShape to Cylinder