JSM: Added module and TS file for MMDPhysics.

docs/manual/en/introduction/Import-via-modules.html

@@ -80,6 +80,7 @@
 					<ul>
 						<li>AnimationClipCreator</li>
 						<li>CCDIKSolver</li>
+						<li>MMDPhysics</li>
 						<li>TimelinerController</li>
 					</ul>
 				</li>

examples/js/animation/MMDPhysics.js

@@ -11,6 +11,8 @@
  *  - Physics in Worker
  */
 
+/* global Ammo */
+
 THREE.MMDPhysics = ( function () {
 
 	/**
@@ -137,7 +139,7 @@ THREE.MMDPhysics = ( function () {
 		 */
 		reset: function () {
 
-			for ( var i = 0, il = this.bodies.length; i < il; i++ ) {
+			for ( var i = 0, il = this.bodies.length; i < il; i ++ ) {
 
 				this.bodies[ i ].reset();
 
@@ -155,7 +157,7 @@ THREE.MMDPhysics = ( function () {
 		 */
 		warmup: function ( cycles ) {
 
-			for ( var i = 0; i < cycles; i++ ) {
+			for ( var i = 0; i < cycles; i ++ ) {
 
 				this.update( 1 / 60 );
 
@@ -258,7 +260,7 @@ THREE.MMDPhysics = ( function () {
 
 		_initRigidBodies: function ( rigidBodies ) {
 
-			for ( var i = 0, il = rigidBodies.length; i < il; i++ ) {
+			for ( var i = 0, il = rigidBodies.length; i < il; i ++ ) {
 
 				this.bodies.push( new RigidBody(
 					this.mesh, this.world, rigidBodies[ i ], this.manager ) );
@@ -269,7 +271,7 @@ THREE.MMDPhysics = ( function () {
 
 		_initConstraints: function ( constraints ) {
 
-			for ( var i = 0, il = constraints.length; i < il; i++ ) {
+			for ( var i = 0, il = constraints.length; i < il; i ++ ) {
 
 				var params = constraints[ i ];
 				var bodyA = this.bodies[ params.rigidBodyIndex1 ];
@@ -307,7 +309,7 @@ THREE.MMDPhysics = ( function () {
 
 		_updateRigidBodies: function () {
 
-			for ( var i = 0, il = this.bodies.length; i < il; i++ ) {
+			for ( var i = 0, il = this.bodies.length; i < il; i ++ ) {
 
 				this.bodies[ i ].updateFromBone();
 
@@ -317,7 +319,7 @@ THREE.MMDPhysics = ( function () {
 
 		_updateBones: function () {
 
-			for ( var i = 0, il = this.bodies.length; i < il; i++ ) {
+			for ( var i = 0, il = this.bodies.length; i < il; i ++ ) {
 
 				this.bodies[ i ].updateBone();
 
@@ -476,32 +478,32 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		getOrigin: function( t ) {
+		getOrigin: function ( t ) {
 
 			return t.getOrigin();
 
 		},
 
-		setOrigin: function( t, v ) {
+		setOrigin: function ( t, v ) {
 
 			t.getOrigin().setValue( v.x(), v.y(), v.z() );
 
 		},
 
-		copyOrigin: function( t1, t2 ) {
+		copyOrigin: function ( t1, t2 ) {
 
 			var o = t2.getOrigin();
 			this.setOrigin( t1, o );
 
 		},
 
-		setBasis: function( t, q ) {
+		setBasis: function ( t, q ) {
 
 			t.setRotation( q );
 
 		},
 
-		setBasisFromMatrix3: function( t, m ) {
+		setBasisFromMatrix3: function ( t, m ) {
 
 			var q = this.matrix3ToQuaternion( m );
 			this.setBasis( t, q );
@@ -626,7 +628,7 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		addVector3: function( v1, v2 ) {
+		addVector3: function ( v1, v2 ) {
 
 			var v = this.allocVector3();
 			v.setValue( v1.x() + v2.x(), v1.y() + v2.y(), v1.z() + v2.z() );
@@ -634,13 +636,13 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		dotVectors3: function( v1, v2 ) {
+		dotVectors3: function ( v1, v2 ) {
 
 			return v1.x() * v2.x() + v1.y() * v2.y() + v1.z() * v2.z();
 
 		},
 
-		rowOfMatrix3: function( m, i ) {
+		rowOfMatrix3: function ( m, i ) {
 
 			var v = this.allocVector3();
 			v.setValue( m[ i * 3 + 0 ], m[ i * 3 + 1 ], m[ i * 3 + 2 ] );
@@ -648,7 +650,7 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		columnOfMatrix3: function( m, i ) {
+		columnOfMatrix3: function ( m, i ) {
 
 			var v = this.allocVector3();
 			v.setValue( m[ i + 0 ], m[ i + 3 ], m[ i + 6 ] );
@@ -656,10 +658,10 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		negativeVector3: function( v ) {
+		negativeVector3: function ( v ) {
 
 			var v2 = this.allocVector3();
-			v2.setValue( -v.x(), -v.y(), -v.z() );
+			v2.setValue( - v.x(), - v.y(), - v.z() );
 			return v2;
 
 		},
@@ -685,7 +687,7 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		transposeMatrix3: function( m ) {
+		transposeMatrix3: function ( m ) {
 
 			var m2 = [];
 			m2[ 0 ] = m[ 0 ];
@@ -736,12 +738,12 @@ THREE.MMDPhysics = ( function () {
 
 		},
 
-		matrix3ToQuaternion: function( m ) {
+		matrix3ToQuaternion: function ( m ) {
 
 			var t = m[ 0 ] + m[ 4 ] + m[ 8 ];
 			var s, x, y, z, w;
 
-			if( t > 0 ) {
+			if ( t > 0 ) {
 
 				s = Math.sqrt( t + 1.0 ) * 2;
 				w = 0.25 * s;
@@ -749,7 +751,7 @@ THREE.MMDPhysics = ( function () {
 				y = ( m[ 2 ] - m[ 6 ] ) / s;
 				z = ( m[ 3 ] - m[ 1 ] ) / s;
 
-			} else if( ( m[ 0 ] > m[ 4 ] ) && ( m[ 0 ] > m[ 8 ] ) ) {
+			} else if ( ( m[ 0 ] > m[ 4 ] ) && ( m[ 0 ] > m[ 8 ] ) ) {
 
 				s = Math.sqrt( 1.0 + m[ 0 ] - m[ 4 ] - m[ 8 ] ) * 2;
 				w = ( m[ 7 ] - m[ 5 ] ) / s;
@@ -757,7 +759,7 @@ THREE.MMDPhysics = ( function () {
 				y = ( m[ 1 ] + m[ 3 ] ) / s;
 				z = ( m[ 2 ] + m[ 6 ] ) / s;
 
-			} else if( m[ 4 ] > m[ 8 ] ) {
+			} else if ( m[ 4 ] > m[ 8 ] ) {
 
 				s = Math.sqrt( 1.0 + m[ 4 ] - m[ 0 ] - m[ 8 ] ) * 2;
 				w = ( m[ 2 ] - m[ 6 ] ) / s;
@@ -794,7 +796,7 @@ THREE.MMDPhysics = ( function () {
 	 */
 	function RigidBody( mesh, world, params, manager ) {
 
-		this.mesh  = mesh;
+		this.mesh = mesh;
 		this.world = world;
 		this.params = params;
 		this.manager = manager;
@@ -882,7 +884,7 @@ THREE.MMDPhysics = ( function () {
 
 			function generateShape( p ) {
 
-				switch( p.shapeType ) {
+				switch ( p.shapeType ) {
 
 					case 0:
 						return new Ammo.btSphereShape( p.width );
@@ -912,7 +914,7 @@ THREE.MMDPhysics = ( function () {
 			var localInertia = manager.allocVector3();
 			localInertia.setValue( 0, 0, 0 );
 
-			if( weight !== 0 ) {
+			if ( weight !== 0 ) {
 
 				shape.calculateLocalInertia( weight, localInertia );
 
@@ -1103,7 +1105,7 @@ THREE.MMDPhysics = ( function () {
 	 */
 	function Constraint( mesh, world, bodyA, bodyB, params, manager ) {
 
-		this.mesh  = mesh;
+		this.mesh = mesh;
 		this.world = world;
 		this.bodyA = bodyA;
 		this.bodyB = bodyB;
@@ -1171,9 +1173,9 @@ THREE.MMDPhysics = ( function () {
 			constraint.setAngularLowerLimit( all );
 			constraint.setAngularUpperLimit( aul );
 
-			for ( var i = 0; i < 3; i++ ) {
+			for ( var i = 0; i < 3; i ++ ) {
 
-				if( params.springPosition[ i ] !== 0 ) {
+				if ( params.springPosition[ i ] !== 0 ) {
 
 					constraint.enableSpring( i, true );
 					constraint.setStiffness( i, params.springPosition[ i ] );
@@ -1182,9 +1184,9 @@ THREE.MMDPhysics = ( function () {
 
 			}
 
-			for ( var i = 0; i < 3; i++ ) {
+			for ( var i = 0; i < 3; i ++ ) {
 
-				if( params.springRotation[ i ] !== 0 ) {
+				if ( params.springRotation[ i ] !== 0 ) {
 
 					constraint.enableSpring( i + 3, true );
 					constraint.setStiffness( i + 3, params.springRotation[ i ] );

examples/jsm/animation/MMDPhysics.d.ts

@@ -0,0 +1,109 @@
+import {
+  Bone,
+  Euler,
+  Matrix4,
+  Object3D,
+  Quaternion,
+  SkinnedMesh,
+  Vector3
+} from '../../../src/Three';
+
+export interface MMDPhysicsParameter {
+  unitStep?: number;
+  maxStepNum?: number;
+  gravity?: Vector3;
+}
+
+export class MMDPhysics {
+  constructor(mesh: SkinnedMesh, rigidBodyParams: object[], constraintParams?: object[], params?: MMDPhysicsParameter);
+  manager: ResourceManager;
+  mesh: SkinnedMesh;
+  unitStep: number;
+  maxStepNum: number;
+  gravity: Vector3;
+  world: null;
+  bodies: RigidBody[];
+  constraints: Constraint[];
+
+  update(delta: number): this;
+  reset(): this;
+  warmup(cycles: number): this;
+  setGravity(gravity: Vector3): this;
+  createHelper(): MMDPhysicsHelper;
+}
+
+export class ResourceManager{
+  constructor();
+  threeVector3s: Vector3[];
+  threeMatrix4s: Matrix4[];
+  threeQuaternions: Quaternion[];
+  threeEulers: Euler[];
+  transforms: object[];
+  quaternions: object[];
+  vector3s: object[];
+
+  allocThreeVector3(): void;
+  freeThreeVector3(v: Vector3): void;
+  allocThreeMatrix4(): void;
+  freeThreeMatrix4(m: Matrix4): void;
+  allocThreeQuaternion(): void;
+  freeThreeQuaternion(q: Quaternion): void;
+  allocThreeEuler(): void;
+  freeThreeEuler(e: Euler): void;
+  allocTransform(): void;
+  freeTransform(t: object): void;
+  allocQuaternion(): void;
+  freeQuaternion(q: object): void;
+  allocVector3(): void;
+  freeVector3(v: object): void;
+  setIdentity(): void;
+  getBasis(t: object): object;
+  getBasisAsMatrix3(t: object): object;
+  getOrigin(t: object): object;
+  setOrigin(t: object, v: object): void;
+  copyOrigin(t1: object, t2: object): void;
+  setBasis(t: object, q: object): void;
+  setBasisFromMatrix3(t: object, m: object): void;
+  setOriginFromArray3(t: object, a: number[]): void;
+  setOriginFromThreeVector3(t: object, v: Vector3): void;
+  setBasisFromArray3(t: object, a: number[]): void;
+  setBasisFromThreeQuaternion(t: object, a: Quaternion): void;
+  multiplyTransforms(t1: object, t2: object): object;
+  inverseTransform(t: object): object;
+  multiplyMatrices3(m1: object, m2: object): object;
+  addVector3(v1: object, v2: object): object;
+  dotVectors3(v1: object, v2: object): number;
+  rowOfMatrix3(m: object, i: number): object;
+  columnOfMatrix3(m: object, i: number): object;
+  negativeVector3(v: object): object;
+  multiplyMatrix3ByVector3(m: object, v: object): object;
+  transposeMatrix3(m: object): object;
+  quaternionToMatrix3(q: object): object;
+  matrix3ToQuaternion(m: object): object;
+}
+
+export class RigidBody{
+  constructor(mesh: SkinnedMesh, world: object, params: object, manager: ResourceManager);
+  mesh: SkinnedMesh;
+  world: object;
+  params: object;
+  manager: ResourceManager;
+
+  body: object;
+  bone: Bone;
+  boneOffsetForm: object;
+  boneOffsetFormInverse: object;
+
+  reset(): this;
+  updateFromBone(): this;
+  updateBone(): this;
+}
+
+export class Constraint{
+  constructor(mesh: SkinnedMesh, world: object, bodyA: RigidBody, bodyB: RigidBody, params: object, manager: ResourceManager);
+
+}
+
+export class MMDPhysicsHelper extends Object3D {
+  constructor();
+}

examples/jsm/animation/MMDPhysics.js

@@ -0,0 +1,1428 @@
+/**
+ * @author takahiro / https://github.com/takahirox
+ *
+ * Dependencies
+ *  - Ammo.js https://github.com/kripken/ammo.js
+ *
+ * MMDPhysics calculates physics with Ammo(Bullet based JavaScript Physics engine)
+ * for MMD model loaded by MMDLoader.
+ *
+ * TODO
+ *  - Physics in Worker
+ */
+
+import {
+	Bone,
+	BoxBufferGeometry,
+	Color,
+	CylinderBufferGeometry,
+	Euler,
+	Matrix4,
+	Mesh,
+	MeshBasicMaterial,
+	Object3D,
+	Quaternion,
+	SphereBufferGeometry,
+	Vector3
+} from "../../../build/three.module.js";
+
+/* global Ammo */
+
+var MMDPhysics = ( function () {
+
+	/**
+	 * @param {THREE.SkinnedMesh} mesh
+	 * @param {Array<Object>} rigidBodyParams
+	 * @param {Array<Object>} (optional) constraintParams
+	 * @param {Object} params - (optional)
+	 * @param {Number} params.unitStep - Default is 1 / 65.
+	 * @param {Integer} params.maxStepNum - Default is 3.
+	 * @param {Vector3} params.gravity - Default is ( 0, - 9.8 * 10, 0 )
+	 */
+	function MMDPhysics( mesh, rigidBodyParams, constraintParams, params ) {
+
+		if ( typeof Ammo === 'undefined' ) {
+
+			throw new Error( 'THREE.MMDPhysics: Import ammo.js https://github.com/kripken/ammo.js' );
+
+		}
+
+		constraintParams = constraintParams || [];
+		params = params || {};
+
+		this.manager = new ResourceManager();
+
+		this.mesh = mesh;
+
+		/*
+		 * I don't know why but 1/60 unitStep easily breaks models
+		 * so I set it 1/65 so far.
+		 * Don't set too small unitStep because
+		 * the smaller unitStep can make the performance worse.
+		 */
+		this.unitStep = ( params.unitStep !== undefined ) ? params.unitStep : 1 / 65;
+		this.maxStepNum = ( params.maxStepNum !== undefined ) ? params.maxStepNum : 3;
+		this.gravity = new Vector3( 0, - 9.8 * 10, 0 );
+
+		if ( params.gravity !== undefined ) this.gravity.copy( params.gravity );
+
+		this.world = params.world !== undefined ? params.world : null; // experimental
+
+		this.bodies = [];
+		this.constraints = [];
+
+		this._init( mesh, rigidBodyParams, constraintParams );
+
+	}
+
+	MMDPhysics.prototype = {
+
+		constructor: MMDPhysics,
+
+		/**
+		 * Advances Physics calculation and updates bones.
+		 *
+		 * @param {Number} delta - time in second
+		 * @return {MMDPhysics}
+		 */
+		update: function ( delta ) {
+
+			var manager = this.manager;
+			var mesh = this.mesh;
+
+			// rigid bodies and constrains are for
+			// mesh's world scale (1, 1, 1).
+			// Convert to (1, 1, 1) if it isn't.
+
+			var isNonDefaultScale = false;
+
+			var position = manager.allocThreeVector3();
+			var quaternion = manager.allocThreeQuaternion();
+			var scale = manager.allocThreeVector3();
+
+			mesh.matrixWorld.decompose( position, quaternion, scale );
+
+			if ( scale.x !== 1 || scale.y !== 1 || scale.z !== 1 ) {
+
+				isNonDefaultScale = true;
+
+			}
+
+			var parent;
+
+			if ( isNonDefaultScale ) {
+
+				parent = mesh.parent;
+
+				if ( parent !== null ) mesh.parent = null;
+
+				scale.copy( this.mesh.scale );
+
+				mesh.scale.set( 1, 1, 1 );
+				mesh.updateMatrixWorld( true );
+
+			}
+
+			// calculate physics and update bones
+
+			this._updateRigidBodies();
+			this._stepSimulation( delta );
+			this._updateBones();
+
+			// restore mesh if converted above
+
+			if ( isNonDefaultScale ) {
+
+				if ( parent !== null ) mesh.parent = parent;
+
+				mesh.scale.copy( scale );
+
+			}
+
+			manager.freeThreeVector3( scale );
+			manager.freeThreeQuaternion( quaternion );
+			manager.freeThreeVector3( position );
+
+			return this;
+
+		},
+
+		/**
+		 * Resets rigid bodies transorm to current bone's.
+		 *
+		 * @return {MMDPhysics}
+		 */
+		reset: function () {
+
+			for ( var i = 0, il = this.bodies.length; i < il; i ++ ) {
+
+				this.bodies[ i ].reset();
+
+			}
+
+			return this;
+
+		},
+
+		/**
+		 * Warm ups Rigid bodies. Calculates cycles steps.
+		 *
+		 * @param {Integer} cycles
+		 * @return {MMDPhysics}
+		 */
+		warmup: function ( cycles ) {
+
+			for ( var i = 0; i < cycles; i ++ ) {
+
+				this.update( 1 / 60 );
+
+			}
+
+			return this;
+
+		},
+
+		/**
+		 * Sets gravity.
+		 *
+		 * @param {Vector3} gravity
+		 * @return {MMDPhysicsHelper}
+		 */
+		setGravity: function ( gravity ) {
+
+			this.world.setGravity( new Ammo.btVector3( gravity.x, gravity.y, gravity.z ) );
+			this.gravity.copy( gravity );
+
+			return this;
+
+		},
+
+		/**
+		 * Creates MMDPhysicsHelper
+		 *
+		 * @return {MMDPhysicsHelper}
+		 */
+		createHelper: function () {
+
+			return new MMDPhysicsHelper( this.mesh, this );
+
+		},
+
+		// private methods
+
+		_init: function ( mesh, rigidBodyParams, constraintParams ) {
+
+			var manager = this.manager;
+
+			// rigid body/constraint parameters are for
+			// mesh's default world transform as position(0, 0, 0),
+			// quaternion(0, 0, 0, 1) and scale(0, 0, 0)
+
+			var parent = mesh.parent;
+
+			if ( parent !== null ) parent = null;
+
+			var currentPosition = manager.allocThreeVector3();
+			var currentQuaternion = manager.allocThreeQuaternion();
+			var currentScale = manager.allocThreeVector3();
+
+			currentPosition.copy( mesh.position );
+			currentQuaternion.copy( mesh.quaternion );
+			currentScale.copy( mesh.scale );
+
+			mesh.position.set( 0, 0, 0 );
+			mesh.quaternion.set( 0, 0, 0, 1 );
+			mesh.scale.set( 1, 1, 1 );
+
+			mesh.updateMatrixWorld( true );
+
+			if ( this.world === null ) {
+
+				this.world = this._createWorld();
+				this.setGravity( this.gravity );
+
+			}
+
+			this._initRigidBodies( rigidBodyParams );
+			this._initConstraints( constraintParams );
+
+			if ( parent !== null ) mesh.parent = parent;
+
+			mesh.position.copy( currentPosition );
+			mesh.quaternion.copy( currentQuaternion );
+			mesh.scale.copy( currentScale );
+
+			mesh.updateMatrixWorld( true );
+
+			this.reset();
+
+			manager.freeThreeVector3( currentPosition );
+			manager.freeThreeQuaternion( currentQuaternion );
+			manager.freeThreeVector3( currentScale );
+
+		},
+
+		_createWorld: function () {
+
+			var config = new Ammo.btDefaultCollisionConfiguration();
+			var dispatcher = new Ammo.btCollisionDispatcher( config );
+			var cache = new Ammo.btDbvtBroadphase();
+			var solver = new Ammo.btSequentialImpulseConstraintSolver();
+			var world = new Ammo.btDiscreteDynamicsWorld( dispatcher, cache, solver, config );
+			return world;
+
+		},
+
+		_initRigidBodies: function ( rigidBodies ) {
+
+			for ( var i = 0, il = rigidBodies.length; i < il; i ++ ) {
+
+				this.bodies.push( new RigidBody(
+					this.mesh, this.world, rigidBodies[ i ], this.manager ) );
+
+			}
+
+		},
+
+		_initConstraints: function ( constraints ) {
+
+			for ( var i = 0, il = constraints.length; i < il; i ++ ) {
+
+				var params = constraints[ i ];
+				var bodyA = this.bodies[ params.rigidBodyIndex1 ];
+				var bodyB = this.bodies[ params.rigidBodyIndex2 ];
+				this.constraints.push( new Constraint(
+					this.mesh, this.world, bodyA, bodyB, params, this.manager ) );
+
+			}
+
+
+		},
+
+		_stepSimulation: function ( delta ) {
+
+			var unitStep = this.unitStep;
+			var stepTime = delta;
+			var maxStepNum = ( ( delta / unitStep ) | 0 ) + 1;
+
+			if ( stepTime < unitStep ) {
+
+				stepTime = unitStep;
+				maxStepNum = 1;
+
+			}
+
+			if ( maxStepNum > this.maxStepNum ) {
+
+				maxStepNum = this.maxStepNum;
+
+			}
+
+			this.world.stepSimulation( stepTime, maxStepNum, unitStep );
+
+		},
+
+		_updateRigidBodies: function () {
+
+			for ( var i = 0, il = this.bodies.length; i < il; i ++ ) {
+
+				this.bodies[ i ].updateFromBone();
+
+			}
+
+		},
+
+		_updateBones: function () {
+
+			for ( var i = 0, il = this.bodies.length; i < il; i ++ ) {
+
+				this.bodies[ i ].updateBone();
+
+			}
+
+		}
+
+	};
+
+	/**
+	 * This manager's responsibilies are
+	 *
+	 * 1. manage Ammo.js and Three.js object resources and
+	 *    improve the performance and the memory consumption by
+	 *    reusing objects.
+	 *
+	 * 2. provide simple Ammo object operations.
+	 */
+	function ResourceManager() {
+
+		// for Three.js
+		this.threeVector3s = [];
+		this.threeMatrix4s = [];
+		this.threeQuaternions = [];
+		this.threeEulers = [];
+
+		// for Ammo.js
+		this.transforms = [];
+		this.quaternions = [];
+		this.vector3s = [];
+
+	}
+
+	ResourceManager.prototype = {
+
+		constructor: ResourceManager,
+
+		allocThreeVector3: function () {
+
+			return ( this.threeVector3s.length > 0 )
+				? this.threeVector3s.pop()
+				: new Vector3();
+
+		},
+
+		freeThreeVector3: function ( v ) {
+
+			this.threeVector3s.push( v );
+
+		},
+
+		allocThreeMatrix4: function () {
+
+			return ( this.threeMatrix4s.length > 0 )
+				? this.threeMatrix4s.pop()
+				: new Matrix4();
+
+		},
+
+		freeThreeMatrix4: function ( m ) {
+
+			this.threeMatrix4s.push( m );
+
+		},
+
+		allocThreeQuaternion: function () {
+
+			return ( this.threeQuaternions.length > 0 )
+				? this.threeQuaternions.pop()
+				: new Quaternion();
+
+		},
+
+		freeThreeQuaternion: function ( q ) {
+
+			this.threeQuaternions.push( q );
+
+		},
+
+		allocThreeEuler: function () {
+
+			return ( this.threeEulers.length > 0 )
+				? this.threeEulers.pop()
+				: new Euler();
+
+		},
+
+		freeThreeEuler: function ( e ) {
+
+			this.threeEulers.push( e );
+
+		},
+
+		allocTransform: function () {
+
+			return ( this.transforms.length > 0 )
+				? this.transforms.pop()
+				: new Ammo.btTransform();
+
+		},
+
+		freeTransform: function ( t ) {
+
+			this.transforms.push( t );
+
+		},
+
+		allocQuaternion: function () {
+
+			return ( this.quaternions.length > 0 )
+				? this.quaternions.pop()
+				: new Ammo.btQuaternion();
+
+		},
+
+		freeQuaternion: function ( q ) {
+
+			this.quaternions.push( q );
+
+		},
+
+		allocVector3: function () {
+
+			return ( this.vector3s.length > 0 )
+				? this.vector3s.pop()
+				: new Ammo.btVector3();
+
+		},
+
+		freeVector3: function ( v ) {
+
+			this.vector3s.push( v );
+
+		},
+
+		setIdentity: function ( t ) {
+
+			t.setIdentity();
+
+		},
+
+		getBasis: function ( t ) {
+
+			var q = this.allocQuaternion();
+			t.getBasis().getRotation( q );
+			return q;
+
+		},
+
+		getBasisAsMatrix3: function ( t ) {
+
+			var q = this.getBasis( t );
+			var m = this.quaternionToMatrix3( q );
+			this.freeQuaternion( q );
+			return m;
+
+		},
+
+		getOrigin: function ( t ) {
+
+			return t.getOrigin();
+
+		},
+
+		setOrigin: function ( t, v ) {
+
+			t.getOrigin().setValue( v.x(), v.y(), v.z() );
+
+		},
+
+		copyOrigin: function ( t1, t2 ) {
+
+			var o = t2.getOrigin();
+			this.setOrigin( t1, o );
+
+		},
+
+		setBasis: function ( t, q ) {
+
+			t.setRotation( q );
+
+		},
+
+		setBasisFromMatrix3: function ( t, m ) {
+
+			var q = this.matrix3ToQuaternion( m );
+			this.setBasis( t, q );
+			this.freeQuaternion( q );
+
+		},
+
+		setOriginFromArray3: function ( t, a ) {
+
+			t.getOrigin().setValue( a[ 0 ], a[ 1 ], a[ 2 ] );
+
+		},
+
+		setOriginFromThreeVector3: function ( t, v ) {
+
+			t.getOrigin().setValue( v.x, v.y, v.z );
+
+		},
+
+		setBasisFromArray3: function ( t, a ) {
+
+			var thQ = this.allocThreeQuaternion();
+			var thE = this.allocThreeEuler();
+			thE.set( a[ 0 ], a[ 1 ], a[ 2 ] );
+			this.setBasisFromThreeQuaternion( t, thQ.setFromEuler( thE ) );
+
+			this.freeThreeEuler( thE );
+			this.freeThreeQuaternion( thQ );
+
+		},
+
+		setBasisFromThreeQuaternion: function ( t, a ) {
+
+			var q = this.allocQuaternion();
+
+			q.setX( a.x );
+			q.setY( a.y );
+			q.setZ( a.z );
+			q.setW( a.w );
+			this.setBasis( t, q );
+
+			this.freeQuaternion( q );
+
+		},
+
+		multiplyTransforms: function ( t1, t2 ) {
+
+			var t = this.allocTransform();
+			this.setIdentity( t );
+
+			var m1 = this.getBasisAsMatrix3( t1 );
+			var m2 = this.getBasisAsMatrix3( t2 );
+
+			var o1 = this.getOrigin( t1 );
+			var o2 = this.getOrigin( t2 );
+
+			var v1 = this.multiplyMatrix3ByVector3( m1, o2 );
+			var v2 = this.addVector3( v1, o1 );
+			this.setOrigin( t, v2 );
+
+			var m3 = this.multiplyMatrices3( m1, m2 );
+			this.setBasisFromMatrix3( t, m3 );
+
+			this.freeVector3( v1 );
+			this.freeVector3( v2 );
+
+			return t;
+
+		},
+
+		inverseTransform: function ( t ) {
+
+			var t2 = this.allocTransform();
+
+			var m1 = this.getBasisAsMatrix3( t );
+			var o = this.getOrigin( t );
+
+			var m2 = this.transposeMatrix3( m1 );
+			var v1 = this.negativeVector3( o );
+			var v2 = this.multiplyMatrix3ByVector3( m2, v1 );
+
+			this.setOrigin( t2, v2 );
+			this.setBasisFromMatrix3( t2, m2 );
+
+			this.freeVector3( v1 );
+			this.freeVector3( v2 );
+
+			return t2;
+
+		},
+
+		multiplyMatrices3: function ( m1, m2 ) {
+
+			var m3 = [];
+
+			var v10 = this.rowOfMatrix3( m1, 0 );
+			var v11 = this.rowOfMatrix3( m1, 1 );
+			var v12 = this.rowOfMatrix3( m1, 2 );
+
+			var v20 = this.columnOfMatrix3( m2, 0 );
+			var v21 = this.columnOfMatrix3( m2, 1 );
+			var v22 = this.columnOfMatrix3( m2, 2 );
+
+			m3[ 0 ] = this.dotVectors3( v10, v20 );
+			m3[ 1 ] = this.dotVectors3( v10, v21 );
+			m3[ 2 ] = this.dotVectors3( v10, v22 );
+			m3[ 3 ] = this.dotVectors3( v11, v20 );
+			m3[ 4 ] = this.dotVectors3( v11, v21 );
+			m3[ 5 ] = this.dotVectors3( v11, v22 );
+			m3[ 6 ] = this.dotVectors3( v12, v20 );
+			m3[ 7 ] = this.dotVectors3( v12, v21 );
+			m3[ 8 ] = this.dotVectors3( v12, v22 );
+
+			this.freeVector3( v10 );
+			this.freeVector3( v11 );
+			this.freeVector3( v12 );
+			this.freeVector3( v20 );
+			this.freeVector3( v21 );
+			this.freeVector3( v22 );
+
+			return m3;
+
+		},
+
+		addVector3: function ( v1, v2 ) {
+
+			var v = this.allocVector3();
+			v.setValue( v1.x() + v2.x(), v1.y() + v2.y(), v1.z() + v2.z() );
+			return v;
+
+		},
+
+		dotVectors3: function ( v1, v2 ) {
+
+			return v1.x() * v2.x() + v1.y() * v2.y() + v1.z() * v2.z();
+
+		},
+
+		rowOfMatrix3: function ( m, i ) {
+
+			var v = this.allocVector3();
+			v.setValue( m[ i * 3 + 0 ], m[ i * 3 + 1 ], m[ i * 3 + 2 ] );
+			return v;
+
+		},
+
+		columnOfMatrix3: function ( m, i ) {
+
+			var v = this.allocVector3();
+			v.setValue( m[ i + 0 ], m[ i + 3 ], m[ i + 6 ] );
+			return v;
+
+		},
+
+		negativeVector3: function ( v ) {
+
+			var v2 = this.allocVector3();
+			v2.setValue( - v.x(), - v.y(), - v.z() );
+			return v2;
+
+		},
+
+		multiplyMatrix3ByVector3: function ( m, v ) {
+
+			var v4 = this.allocVector3();
+
+			var v0 = this.rowOfMatrix3( m, 0 );
+			var v1 = this.rowOfMatrix3( m, 1 );
+			var v2 = this.rowOfMatrix3( m, 2 );
+			var x = this.dotVectors3( v0, v );
+			var y = this.dotVectors3( v1, v );
+			var z = this.dotVectors3( v2, v );
+
+			v4.setValue( x, y, z );
+
+			this.freeVector3( v0 );
+			this.freeVector3( v1 );
+			this.freeVector3( v2 );
+
+			return v4;
+
+		},
+
+		transposeMatrix3: function ( m ) {
+
+			var m2 = [];
+			m2[ 0 ] = m[ 0 ];
+			m2[ 1 ] = m[ 3 ];
+			m2[ 2 ] = m[ 6 ];
+			m2[ 3 ] = m[ 1 ];
+			m2[ 4 ] = m[ 4 ];
+			m2[ 5 ] = m[ 7 ];
+			m2[ 6 ] = m[ 2 ];
+			m2[ 7 ] = m[ 5 ];
+			m2[ 8 ] = m[ 8 ];
+			return m2;
+
+		},
+
+		quaternionToMatrix3: function ( q ) {
+
+			var m = [];
+
+			var x = q.x();
+			var y = q.y();
+			var z = q.z();
+			var w = q.w();
+
+			var xx = x * x;
+			var yy = y * y;
+			var zz = z * z;
+
+			var xy = x * y;
+			var yz = y * z;
+			var zx = z * x;
+
+			var xw = x * w;
+			var yw = y * w;
+			var zw = z * w;
+
+			m[ 0 ] = 1 - 2 * ( yy + zz );
+			m[ 1 ] = 2 * ( xy - zw );
+			m[ 2 ] = 2 * ( zx + yw );
+			m[ 3 ] = 2 * ( xy + zw );
+			m[ 4 ] = 1 - 2 * ( zz + xx );
+			m[ 5 ] = 2 * ( yz - xw );
+			m[ 6 ] = 2 * ( zx - yw );
+			m[ 7 ] = 2 * ( yz + xw );
+			m[ 8 ] = 1 - 2 * ( xx + yy );
+
+			return m;
+
+		},
+
+		matrix3ToQuaternion: function ( m ) {
+
+			var t = m[ 0 ] + m[ 4 ] + m[ 8 ];
+			var s, x, y, z, w;
+
+			if ( t > 0 ) {
+
+				s = Math.sqrt( t + 1.0 ) * 2;
+				w = 0.25 * s;
+				x = ( m[ 7 ] - m[ 5 ] ) / s;
+				y = ( m[ 2 ] - m[ 6 ] ) / s;
+				z = ( m[ 3 ] - m[ 1 ] ) / s;
+
+			} else if ( ( m[ 0 ] > m[ 4 ] ) && ( m[ 0 ] > m[ 8 ] ) ) {
+
+				s = Math.sqrt( 1.0 + m[ 0 ] - m[ 4 ] - m[ 8 ] ) * 2;
+				w = ( m[ 7 ] - m[ 5 ] ) / s;
+				x = 0.25 * s;
+				y = ( m[ 1 ] + m[ 3 ] ) / s;
+				z = ( m[ 2 ] + m[ 6 ] ) / s;
+
+			} else if ( m[ 4 ] > m[ 8 ] ) {
+
+				s = Math.sqrt( 1.0 + m[ 4 ] - m[ 0 ] - m[ 8 ] ) * 2;
+				w = ( m[ 2 ] - m[ 6 ] ) / s;
+				x = ( m[ 1 ] + m[ 3 ] ) / s;
+				y = 0.25 * s;
+				z = ( m[ 5 ] + m[ 7 ] ) / s;
+
+			} else {
+
+				s = Math.sqrt( 1.0 + m[ 8 ] - m[ 0 ] - m[ 4 ] ) * 2;
+				w = ( m[ 3 ] - m[ 1 ] ) / s;
+				x = ( m[ 2 ] + m[ 6 ] ) / s;
+				y = ( m[ 5 ] + m[ 7 ] ) / s;
+				z = 0.25 * s;
+
+			}
+
+			var q = this.allocQuaternion();
+			q.setX( x );
+			q.setY( y );
+			q.setZ( z );
+			q.setW( w );
+			return q;
+
+		}
+
+	};
+
+	/**
+	 * @param {THREE.SkinnedMesh} mesh
+	 * @param {Ammo.btDiscreteDynamicsWorld} world
+	 * @param {Object} params
+	 * @param {ResourceManager} manager
+	 */
+	function RigidBody( mesh, world, params, manager ) {
+
+		this.mesh = mesh;
+		this.world = world;
+		this.params = params;
+		this.manager = manager;
+
+		this.body = null;
+		this.bone = null;
+		this.boneOffsetForm = null;
+		this.boneOffsetFormInverse = null;
+
+		this._init();
+
+	}
+
+	RigidBody.prototype = {
+
+		constructor: MMDPhysics.RigidBody,
+
+		/**
+		 * Resets rigid body transform to the current bone's.
+		 *
+		 * @return {RigidBody}
+		 */
+		reset: function () {
+
+			this._setTransformFromBone();
+			return this;
+
+		},
+
+		/**
+		 * Updates rigid body's transform from the current bone.
+		 *
+		 * @return {RidigBody}
+		 */
+		updateFromBone: function () {
+
+			if ( this.params.boneIndex !== - 1 &&
+				this.params.type === 0 ) {
+
+				this._setTransformFromBone();
+
+			}
+
+			return this;
+
+		},
+
+		/**
+		 * Updates bone from the current ridid body's transform.
+		 *
+		 * @return {RidigBody}
+		 */
+		updateBone: function () {
+
+			if ( this.params.type === 0 ||
+				this.params.boneIndex === - 1 ) {
+
+				return this;
+
+			}
+
+			this._updateBoneRotation();
+
+			if ( this.params.type === 1 ) {
+
+				this._updateBonePosition();
+
+			}
+
+			this.bone.updateMatrixWorld( true );
+
+			if ( this.params.type === 2 ) {
+
+				this._setPositionFromBone();
+
+			}
+
+			return this;
+
+		},
+
+		// private methods
+
+		_init: function () {
+
+			function generateShape( p ) {
+
+				switch ( p.shapeType ) {
+
+					case 0:
+						return new Ammo.btSphereShape( p.width );
+
+					case 1:
+						return new Ammo.btBoxShape( new Ammo.btVector3( p.width, p.height, p.depth ) );
+
+					case 2:
+						return new Ammo.btCapsuleShape( p.width, p.height );
+
+					default:
+						throw 'unknown shape type ' + p.shapeType;
+
+				}
+
+			}
+
+			var manager = this.manager;
+			var params = this.params;
+			var bones = this.mesh.skeleton.bones;
+			var bone = ( params.boneIndex === - 1 )
+				? new Bone()
+				: bones[ params.boneIndex ];
+
+			var shape = generateShape( params );
+			var weight = ( params.type === 0 ) ? 0 : params.weight;
+			var localInertia = manager.allocVector3();
+			localInertia.setValue( 0, 0, 0 );
+
+			if ( weight !== 0 ) {
+
+				shape.calculateLocalInertia( weight, localInertia );
+
+			}
+
+			var boneOffsetForm = manager.allocTransform();
+			manager.setIdentity( boneOffsetForm );
+			manager.setOriginFromArray3( boneOffsetForm, params.position );
+			manager.setBasisFromArray3( boneOffsetForm, params.rotation );
+
+			var vector = manager.allocThreeVector3();
+			var boneForm = manager.allocTransform();
+			manager.setIdentity( boneForm );
+			manager.setOriginFromThreeVector3( boneForm, bone.getWorldPosition( vector ) );
+
+			var form = manager.multiplyTransforms( boneForm, boneOffsetForm );
+			var state = new Ammo.btDefaultMotionState( form );
+
+			var info = new Ammo.btRigidBodyConstructionInfo( weight, state, shape, localInertia );
+			info.set_m_friction( params.friction );
+			info.set_m_restitution( params.restitution );
+
+			var body = new Ammo.btRigidBody( info );
+
+			if ( params.type === 0 ) {
+
+				body.setCollisionFlags( body.getCollisionFlags() | 2 );
+
+				/*
+				 * It'd be better to comment out this line though in general I should call this method
+				 * because I'm not sure why but physics will be more like MMD's
+				 * if I comment out.
+				 */
+				body.setActivationState( 4 );
+
+			}
+
+			body.setDamping( params.positionDamping, params.rotationDamping );
+			body.setSleepingThresholds( 0, 0 );
+
+			this.world.addRigidBody( body, 1 << params.groupIndex, params.groupTarget );
+
+			this.body = body;
+			this.bone = bone;
+			this.boneOffsetForm = boneOffsetForm;
+			this.boneOffsetFormInverse = manager.inverseTransform( boneOffsetForm );
+
+			manager.freeVector3( localInertia );
+			manager.freeTransform( form );
+			manager.freeTransform( boneForm );
+			manager.freeThreeVector3( vector );
+
+		},
+
+		_getBoneTransform: function () {
+
+			var manager = this.manager;
+			var p = manager.allocThreeVector3();
+			var q = manager.allocThreeQuaternion();
+			var s = manager.allocThreeVector3();
+
+			this.bone.matrixWorld.decompose( p, q, s );
+
+			var tr = manager.allocTransform();
+			manager.setOriginFromThreeVector3( tr, p );
+			manager.setBasisFromThreeQuaternion( tr, q );
+
+			var form = manager.multiplyTransforms( tr, this.boneOffsetForm );
+
+			manager.freeTransform( tr );
+			manager.freeThreeVector3( s );
+			manager.freeThreeQuaternion( q );
+			manager.freeThreeVector3( p );
+
+			return form;
+
+		},
+
+		_getWorldTransformForBone: function () {
+
+			var manager = this.manager;
+			var tr = this.body.getCenterOfMassTransform();
+			return manager.multiplyTransforms( tr, this.boneOffsetFormInverse );
+
+		},
+
+		_setTransformFromBone: function () {
+
+			var manager = this.manager;
+			var form = this._getBoneTransform();
+
+			// TODO: check the most appropriate way to set
+			//this.body.setWorldTransform( form );
+			this.body.setCenterOfMassTransform( form );
+			this.body.getMotionState().setWorldTransform( form );
+
+			manager.freeTransform( form );
+
+		},
+
+		_setPositionFromBone: function () {
+
+			var manager = this.manager;
+			var form = this._getBoneTransform();
+
+			var tr = manager.allocTransform();
+			this.body.getMotionState().getWorldTransform( tr );
+			manager.copyOrigin( tr, form );
+
+			// TODO: check the most appropriate way to set
+			//this.body.setWorldTransform( tr );
+			this.body.setCenterOfMassTransform( tr );
+			this.body.getMotionState().setWorldTransform( tr );
+
+			manager.freeTransform( tr );
+			manager.freeTransform( form );
+
+		},
+
+		_updateBoneRotation: function () {
+
+			var manager = this.manager;
+
+			var tr = this._getWorldTransformForBone();
+			var q = manager.getBasis( tr );
+
+			var thQ = manager.allocThreeQuaternion();
+			var thQ2 = manager.allocThreeQuaternion();
+			var thQ3 = manager.allocThreeQuaternion();
+
+			thQ.set( q.x(), q.y(), q.z(), q.w() );
+			thQ2.setFromRotationMatrix( this.bone.matrixWorld );
+			thQ2.conjugate();
+			thQ2.multiply( thQ );
+
+			//this.bone.quaternion.multiply( thQ2 );
+
+			thQ3.setFromRotationMatrix( this.bone.matrix );
+
+			// Renormalizing quaternion here because repeatedly transforming
+			// quaternion continuously accumulates floating point error and
+			// can end up being overflow. See #15335
+			this.bone.quaternion.copy( thQ2.multiply( thQ3 ).normalize() );
+
+			manager.freeThreeQuaternion( thQ );
+			manager.freeThreeQuaternion( thQ2 );
+			manager.freeThreeQuaternion( thQ3 );
+
+			manager.freeQuaternion( q );
+			manager.freeTransform( tr );
+
+		},
+
+		_updateBonePosition: function () {
+
+			var manager = this.manager;
+
+			var tr = this._getWorldTransformForBone();
+
+			var thV = manager.allocThreeVector3();
+
+			var o = manager.getOrigin( tr );
+			thV.set( o.x(), o.y(), o.z() );
+
+			if ( this.bone.parent ) {
+
+				this.bone.parent.worldToLocal( thV );
+
+			}
+
+			this.bone.position.copy( thV );
+
+			manager.freeThreeVector3( thV );
+
+			manager.freeTransform( tr );
+
+		}
+
+	};
+
+	/**
+	 * @param {THREE.SkinnedMesh} mesh
+	 * @param {Ammo.btDiscreteDynamicsWorld} world
+	 * @param {RigidBody} bodyA
+	 * @param {RigidBody} bodyB
+	 * @param {Object} params
+	 * @param {ResourceManager} manager
+	 */
+	function Constraint( mesh, world, bodyA, bodyB, params, manager ) {
+
+		this.mesh = mesh;
+		this.world = world;
+		this.bodyA = bodyA;
+		this.bodyB = bodyB;
+		this.params = params;
+		this.manager = manager;
+
+		this.constraint = null;
+
+		this._init();
+
+	}
+
+	Constraint.prototype = {
+
+		constructor: Constraint,
+
+		// private method
+
+		_init: function () {
+
+			var manager = this.manager;
+			var params = this.params;
+			var bodyA = this.bodyA;
+			var bodyB = this.bodyB;
+
+			var form = manager.allocTransform();
+			manager.setIdentity( form );
+			manager.setOriginFromArray3( form, params.position );
+			manager.setBasisFromArray3( form, params.rotation );
+
+			var formA = manager.allocTransform();
+			var formB = manager.allocTransform();
+
+			bodyA.body.getMotionState().getWorldTransform( formA );
+			bodyB.body.getMotionState().getWorldTransform( formB );
+
+			var formInverseA = manager.inverseTransform( formA );
+			var formInverseB = manager.inverseTransform( formB );
+
+			var formA2 = manager.multiplyTransforms( formInverseA, form );
+			var formB2 = manager.multiplyTransforms( formInverseB, form );
+
+			var constraint = new Ammo.btGeneric6DofSpringConstraint( bodyA.body, bodyB.body, formA2, formB2, true );
+
+			var lll = manager.allocVector3();
+			var lul = manager.allocVector3();
+			var all = manager.allocVector3();
+			var aul = manager.allocVector3();
+
+			lll.setValue( params.translationLimitation1[ 0 ],
+			              params.translationLimitation1[ 1 ],
+			              params.translationLimitation1[ 2 ] );
+			lul.setValue( params.translationLimitation2[ 0 ],
+			              params.translationLimitation2[ 1 ],
+			              params.translationLimitation2[ 2 ] );
+			all.setValue( params.rotationLimitation1[ 0 ],
+			              params.rotationLimitation1[ 1 ],
+			              params.rotationLimitation1[ 2 ] );
+			aul.setValue( params.rotationLimitation2[ 0 ],
+			              params.rotationLimitation2[ 1 ],
+			              params.rotationLimitation2[ 2 ] );
+
+			constraint.setLinearLowerLimit( lll );
+			constraint.setLinearUpperLimit( lul );
+			constraint.setAngularLowerLimit( all );
+			constraint.setAngularUpperLimit( aul );
+
+			for ( var i = 0; i < 3; i ++ ) {
+
+				if ( params.springPosition[ i ] !== 0 ) {
+
+					constraint.enableSpring( i, true );
+					constraint.setStiffness( i, params.springPosition[ i ] );
+
+				}
+
+			}
+
+			for ( var i = 0; i < 3; i ++ ) {
+
+				if ( params.springRotation[ i ] !== 0 ) {
+
+					constraint.enableSpring( i + 3, true );
+					constraint.setStiffness( i + 3, params.springRotation[ i ] );
+
+				}
+
+			}
+
+			/*
+			 * Currently(10/31/2016) official ammo.js doesn't support
+			 * btGeneric6DofSpringConstraint.setParam method.
+			 * You need custom ammo.js (add the method into idl) if you wanna use.
+			 * By setting this parameter, physics will be more like MMD's
+			 */
+			if ( constraint.setParam !== undefined ) {
+
+				for ( var i = 0; i < 6; i ++ ) {
+
+					// this parameter is from http://www20.atpages.jp/katwat/three.js_r58/examples/mytest37/mmd.three.js
+					constraint.setParam( 2, 0.475, i );
+
+				}
+
+			}
+
+			this.world.addConstraint( constraint, true );
+			this.constraint = constraint;
+
+			manager.freeTransform( form );
+			manager.freeTransform( formA );
+			manager.freeTransform( formB );
+			manager.freeTransform( formInverseA );
+			manager.freeTransform( formInverseB );
+			manager.freeTransform( formA2 );
+			manager.freeTransform( formB2 );
+			manager.freeVector3( lll );
+			manager.freeVector3( lul );
+			manager.freeVector3( all );
+			manager.freeVector3( aul );
+
+		}
+
+	};
+
+	/**
+	 * Visualize Rigid bodies
+	 *
+	 * @param {THREE.SkinnedMesh} mesh
+	 * @param {Physics} physics
+	 */
+	function MMDPhysicsHelper( mesh, physics ) {
+
+		Object3D.call( this );
+
+		this.root = mesh;
+		this.physics = physics;
+
+		this.matrix.copy( mesh.matrixWorld );
+		this.matrixAutoUpdate = false;
+
+		this.materials = [];
+
+		this.materials.push(
+			new MeshBasicMaterial( {
+				color: new Color( 0xff8888 ),
+				wireframe: true,
+				depthTest: false,
+				depthWrite: false,
+				opacity: 0.25,
+				transparent: true
+			} )
+		);
+
+		this.materials.push(
+			new MeshBasicMaterial( {
+				color: new Color( 0x88ff88 ),
+				wireframe: true,
+				depthTest: false,
+				depthWrite: false,
+				opacity: 0.25,
+				transparent: true
+			} )
+		);
+
+		this.materials.push(
+			new MeshBasicMaterial( {
+				color: new Color( 0x8888ff ),
+				wireframe: true,
+				depthTest: false,
+				depthWrite: false,
+				opacity: 0.25,
+				transparent: true
+			} )
+		);
+
+		this._init();
+
+	}
+
+	MMDPhysicsHelper.prototype = Object.assign( Object.create( Object3D.prototype ), {
+
+		constructor: MMDPhysicsHelper,
+
+		/**
+		 * Updates Rigid Bodies visualization.
+		 */
+		updateMatrixWorld: function () {
+
+			var position = new Vector3();
+			var quaternion = new Quaternion();
+			var scale = new Vector3();
+			var matrixWorldInv = new Matrix4();
+
+			return function updateMatrixWorld( force ) {
+
+				var mesh = this.root;
+
+				if ( this.visible ) {
+
+					var bodies = this.physics.bodies;
+
+					matrixWorldInv
+						.copy( mesh.matrixWorld )
+						.decompose( position, quaternion, scale )
+						.compose( position, quaternion, scale.set( 1, 1, 1 ) )
+						.getInverse( matrixWorldInv );
+
+					for ( var i = 0, il = bodies.length; i < il; i ++ ) {
+
+						var body = bodies[ i ].body;
+						var child = this.children[ i ];
+
+						var tr = body.getCenterOfMassTransform();
+						var origin = tr.getOrigin();
+						var rotation = tr.getRotation();
+
+						child.position
+							.set( origin.x(), origin.y(), origin.z() )
+							.applyMatrix4( matrixWorldInv );
+
+						child.quaternion
+							.setFromRotationMatrix( matrixWorldInv )
+							.multiply(
+								quaternion.set(
+									rotation.x(), rotation.y(), rotation.z(), rotation.w() )
+							);
+
+					}
+
+				}
+
+				this.matrix
+					.copy( mesh.matrixWorld )
+					.decompose( position, quaternion, scale )
+					.compose( position, quaternion, scale.set( 1, 1, 1 ) );
+
+				Object3D.prototype.updateMatrixWorld.call( this, force );
+
+			};
+
+		}(),
+
+		// private method
+
+		_init: function () {
+
+			var bodies = this.physics.bodies;
+
+			function createGeometry( param ) {
+
+				switch ( param.shapeType ) {
+
+					case 0:
+						return new SphereBufferGeometry( param.width, 16, 8 );
+
+					case 1:
+						return new BoxBufferGeometry( param.width * 2, param.height * 2, param.depth * 2, 8, 8, 8 );
+
+					case 2:
+						return new createCapsuleGeometry( param.width, param.height, 16, 8 );
+
+					default:
+						return null;
+
+				}
+
+			}
+
+			// copy from http://www20.atpages.jp/katwat/three.js_r58/examples/mytest37/mytest37.js?ver=20160815
+			function createCapsuleGeometry( radius, cylinderHeight, segmentsRadius, segmentsHeight ) {
+
+				var geometry = new CylinderBufferGeometry( radius, radius, cylinderHeight, segmentsRadius, segmentsHeight, true );
+				var upperSphere = new Mesh( new SphereBufferGeometry( radius, segmentsRadius, segmentsHeight, 0, Math.PI * 2, 0, Math.PI / 2 ) );
+				var lowerSphere = new Mesh( new SphereBufferGeometry( radius, segmentsRadius, segmentsHeight, 0, Math.PI * 2, Math.PI / 2, Math.PI / 2 ) );
+
+				upperSphere.position.set( 0, cylinderHeight / 2, 0 );
+				lowerSphere.position.set( 0, - cylinderHeight / 2, 0 );
+
+				upperSphere.updateMatrix();
+				lowerSphere.updateMatrix();
+
+				geometry.merge( upperSphere.geometry, upperSphere.matrix );
+				geometry.merge( lowerSphere.geometry, lowerSphere.matrix );
+
+				return geometry;
+
+			}
+
+			for ( var i = 0, il = bodies.length; i < il; i ++ ) {
+
+				var param = bodies[ i ].params;
+				this.add( new Mesh( createGeometry( param ), this.materials[ param.type ] ) );
+
+			}
+
+		}
+
+	} );
+
+	return MMDPhysics;
+
+} )();
+
+export { MMDPhysics };

utils/modularize.js

@@ -12,6 +12,7 @@ var dstFolder = __dirname + '/../examples/jsm/';
 var files = [
 	{ path: 'animation/AnimationClipCreator.js', dependencies: [], ignoreList: [] },
 	{ path: 'animation/CCDIKSolver.js', dependencies: [], ignoreList: [ 'SkinnedMesh' ] },
+	{ path: 'animation/MMDPhysics.js', dependencies: [], ignoreList: [ 'SkinnedMesh' ] },
 	{ path: 'animation/TimelinerController.js', dependencies: [], ignoreList: [] },
 
 	{ path: 'cameras/CinematicCamera.js', dependencies: [ { name: 'BokehShader', path: 'shaders/BokehShader2.js' }, { name: 'BokehDepthShader', path: 'shaders/BokehShader2.js' } ], ignoreList: [] },