Accueil / npm / three@0.152.0 / examples / jsm / physics / RapierPhysics.js
RapierPhysics.js
async function RapierPhysics() {
const RAPIER = await import( 'https://cdn.skypack.dev/@dimforge/rapier3d-compat@0.11.2' );
await RAPIER.init();
const frameRate = 60;
// Docs: https://rapier.rs/docs/api/javascript/JavaScript3D/
const gravity = { x: 0.0, y: - 9.81, z: 0.0 };
const world = new RAPIER.World( gravity );
function getCollider( geometry ) {
const parameters = geometry.parameters;
// TODO change type to is*
if ( geometry.type === 'BoxGeometry' ) {
const sx = parameters.width !== undefined ? parameters.width / 2 : 0.5;
const sy = parameters.height !== undefined ? parameters.height / 2 : 0.5;
const sz = parameters.depth !== undefined ? parameters.depth / 2 : 0.5;
return RAPIER.ColliderDesc.cuboid( sx, sy, sz );
} else if ( geometry.type === 'SphereGeometry' || geometry.type === 'IcosahedronGeometry' ) {
const radius = parameters.radius !== undefined ? parameters.radius : 1;
return RAPIER.ColliderDesc.ball( radius );
}
return null;
}
const meshes = [];
const meshMap = new WeakMap();
function addMesh( mesh, mass = 0, restitution = 0 ) {
const shape = getCollider( mesh.geometry );
if ( shape !== null ) {
shape.setMass( mass );
shape.setRestitution( restitution );
if ( mesh.isInstancedMesh ) {
handleInstancedMesh( mesh, mass, shape );
} else if ( mesh.isMesh ) {
handleMesh( mesh, mass, shape );
}
}
}
function handleMesh( mesh, mass, shape ) {
const position = mesh.position;
const quaternion = mesh.quaternion;
const desc = mass > 0 ? RAPIER.RigidBodyDesc.dynamic() : RAPIER.RigidBodyDesc.fixed();
desc.setTranslation( position.x, position.y, position.z );
desc.setRotation( quaternion );
const body = world.createRigidBody( desc );
world.createCollider( shape, body );
if ( mass > 0 ) {
meshes.push( mesh );
meshMap.set( mesh, body );
}
}
function handleInstancedMesh( mesh, mass, shape ) {
const array = mesh.instanceMatrix.array;
const bodies = [];
for ( let i = 0; i < mesh.count; i ++ ) {
const index = i * 16;
const desc = mass > 0 ? RAPIER.RigidBodyDesc.dynamic() : RAPIER.RigidBodyDesc.fixed();
desc.setTranslation( array[ index + 12 ], array[ index + 13 ], array[ index + 14 ] );
const body = world.createRigidBody( desc );
world.createCollider( shape, body );
bodies.push( body );
}
if ( mass > 0 ) {
meshes.push( mesh );
meshMap.set( mesh, bodies );
}
}
const vector = { x: 0, y: 0, z: 0 };
function setMeshPosition( mesh, position, index = 0 ) {
if ( mesh.isInstancedMesh ) {
const bodies = meshMap.get( mesh );
const body = bodies[ index ];
body.setAngvel( vector );
body.setLinvel( vector );
body.setTranslation( position );
} else if ( mesh.isMesh ) {
const body = meshMap.get( mesh );
body.setAngvel( vector );
body.setLinvel( vector );
body.setTranslation( position );
}
}
//
let lastTime = 0;
function step() {
const time = performance.now();
if ( lastTime > 0 ) {
const delta = ( time - lastTime ) / 1000;
world.timestep = delta;
world.step();
//
for ( let i = 0, l = meshes.length; i < l; i ++ ) {
const mesh = meshes[ i ];
if ( mesh.isInstancedMesh ) {
const array = mesh.instanceMatrix.array;
const bodies = meshMap.get( mesh );
for ( let j = 0; j < bodies.length; j ++ ) {
const body = bodies[ j ];
const position = body.translation();
const quaternion = body.rotation();
compose( position, quaternion, array, j * 16 );
}
mesh.instanceMatrix.needsUpdate = true;
mesh.computeBoundingSphere();
} else if ( mesh.isMesh ) {
const body = meshMap.get( mesh );
mesh.position.copy( body.translation() );
mesh.quaternion.copy( body.rotation() );
}
}
}
lastTime = time;
}
// animate
setInterval( step, 1000 / frameRate );
return {
addMesh: addMesh,
setMeshPosition: setMeshPosition
};
}
function compose( position, quaternion, array, index ) {
const x = quaternion.x, y = quaternion.y, z = quaternion.z, w = quaternion.w;
const x2 = x + x, y2 = y + y, z2 = z + z;
const xx = x * x2, xy = x * y2, xz = x * z2;
const yy = y * y2, yz = y * z2, zz = z * z2;
const wx = w * x2, wy = w * y2, wz = w * z2;
array[ index + 0 ] = ( 1 - ( yy + zz ) );
array[ index + 1 ] = ( xy + wz );
array[ index + 2 ] = ( xz - wy );
array[ index + 3 ] = 0;
array[ index + 4 ] = ( xy - wz );
array[ index + 5 ] = ( 1 - ( xx + zz ) );
array[ index + 6 ] = ( yz + wx );
array[ index + 7 ] = 0;
array[ index + 8 ] = ( xz + wy );
array[ index + 9 ] = ( yz - wx );
array[ index + 10 ] = ( 1 - ( xx + yy ) );
array[ index + 11 ] = 0;
array[ index + 12 ] = position.x;
array[ index + 13 ] = position.y;
array[ index + 14 ] = position.z;
array[ index + 15 ] = 1;
}
export { RapierPhysics };