var GSSolver = require('../solver/GSSolver')
, Solver = require('../solver/Solver')
, Ray = require('../collision/Ray')
, vec2 = require('../math/vec2')
, Circle = require('../shapes/Circle')
, Convex = require('../shapes/Convex')
, Line = require('../shapes/Line')
, Plane = require('../shapes/Plane')
, Capsule = require('../shapes/Capsule')
, Particle = require('../shapes/Particle')
, EventEmitter = require('../events/EventEmitter')
, Body = require('../objects/Body')
, Shape = require('../shapes/Shape')
, LinearSpring = require('../objects/LinearSpring')
, Material = require('../material/Material')
, ContactMaterial = require('../material/ContactMaterial')
, DistanceConstraint = require('../constraints/DistanceConstraint')
, Constraint = require('../constraints/Constraint')
, LockConstraint = require('../constraints/LockConstraint')
, RevoluteConstraint = require('../constraints/RevoluteConstraint')
, PrismaticConstraint = require('../constraints/PrismaticConstraint')
, GearConstraint = require('../constraints/GearConstraint')
, pkg = require('../../package.json')
, Broadphase = require('../collision/Broadphase')
, AABB = require('../collision/AABB')
, SAPBroadphase = require('../collision/SAPBroadphase')
, Narrowphase = require('../collision/Narrowphase')
, Utils = require('../utils/Utils')
, OverlapKeeper = require('../utils/OverlapKeeper')
, IslandManager = require('./IslandManager')
, RotationalSpring = require('../objects/RotationalSpring');
module.exports = World;
/**
* The dynamics world, where all bodies and constraints live.
*
* @class World
* @constructor
* @param {Object} [options]
* @param {Solver} [options.solver] Defaults to GSSolver.
* @param {Array} [options.gravity] Defaults to y=-9.78.
* @param {Broadphase} [options.broadphase] Defaults to SAPBroadphase
* @param {Boolean} [options.islandSplit=true]
* @extends EventEmitter
*
* @example
* var world = new World({
* gravity: [0, -10],
* broadphase: new SAPBroadphase()
* });
* world.addBody(new Body());
*/
function World(options){
EventEmitter.apply(this);
options = options || {};
/**
* All springs in the world. To add a spring to the world, use {{#crossLink "World/addSpring:method"}}{{/crossLink}}.
*
* @property springs
* @type {Array}
*/
this.springs = [];
/**
* All bodies in the world. To add a body to the world, use {{#crossLink "World/addBody:method"}}{{/crossLink}}.
* @property {Array} bodies
*/
this.bodies = [];
/**
* Disabled body collision pairs. See {{#crossLink "World/disableBodyCollision:method"}}.
* @private
* @property {Array} disabledBodyCollisionPairs
*/
this.disabledBodyCollisionPairs = [];
/**
* The solver used to satisfy constraints and contacts. Default is {{#crossLink "GSSolver"}}{{/crossLink}}.
* @property {Solver} solver
*/
this.solver = options.solver || new GSSolver();
/**
* The narrowphase to use to generate contacts.
*
* @property narrowphase
* @type {Narrowphase}
*/
this.narrowphase = new Narrowphase(this);
/**
* The island manager of this world.
* @property {IslandManager} islandManager
*/
this.islandManager = new IslandManager();
/**
* Gravity in the world. This is applied on all bodies in the beginning of each step().
*
* @property gravity
* @type {Array}
*/
this.gravity = vec2.fromValues(0, -9.78);
if(options.gravity){
vec2.copy(this.gravity, options.gravity);
}
/**
* Gravity to use when approximating the friction max force (mu*mass*gravity).
* @property {Number} frictionGravity
*/
this.frictionGravity = vec2.length(this.gravity) || 10;
/**
* Set to true if you want .frictionGravity to be automatically set to the length of .gravity.
* @property {Boolean} useWorldGravityAsFrictionGravity
* @default true
*/
this.useWorldGravityAsFrictionGravity = true;
/**
* If the length of .gravity is zero, and .useWorldGravityAsFrictionGravity=true, then switch to using .frictionGravity for friction instead. This fallback is useful for gravityless games.
* @property {Boolean} useFrictionGravityOnZeroGravity
* @default true
*/
this.useFrictionGravityOnZeroGravity = true;
/**
* The broadphase algorithm to use.
*
* @property broadphase
* @type {Broadphase}
*/
this.broadphase = options.broadphase || new SAPBroadphase();
this.broadphase.setWorld(this);
/**
* User-added constraints.
*
* @property constraints
* @type {Array}
*/
this.constraints = [];
/**
* Dummy default material in the world, used in .defaultContactMaterial
* @property {Material} defaultMaterial
*/
this.defaultMaterial = new Material();
/**
* The default contact material to use, if no contact material was set for the colliding materials.
* @property {ContactMaterial} defaultContactMaterial
*/
this.defaultContactMaterial = new ContactMaterial(this.defaultMaterial,this.defaultMaterial);
/**
* For keeping track of what time step size we used last step
* @property lastTimeStep
* @type {Number}
*/
this.lastTimeStep = 1/60;
/**
* Enable to automatically apply spring forces each step.
* @property applySpringForces
* @type {Boolean}
* @default true
*/
this.applySpringForces = true;
/**
* Enable to automatically apply body damping each step.
* @property applyDamping
* @type {Boolean}
* @default true
*/
this.applyDamping = true;
/**
* Enable to automatically apply gravity each step.
* @property applyGravity
* @type {Boolean}
* @default true
*/
this.applyGravity = true;
/**
* Enable/disable constraint solving in each step.
* @property solveConstraints
* @type {Boolean}
* @default true
*/
this.solveConstraints = true;
/**
* The ContactMaterials added to the World.
* @property contactMaterials
* @type {Array}
*/
this.contactMaterials = [];
/**
* World time.
* @property time
* @type {Number}
*/
this.time = 0.0;
this.accumulator = 0;
/**
* Is true during step().
* @property {Boolean} stepping
*/
this.stepping = false;
/**
* Bodies that are scheduled to be removed at the end of the step.
* @property {Array} bodiesToBeRemoved
* @private
*/
this.bodiesToBeRemoved = [];
/**
* Whether to enable island splitting. Island splitting can be an advantage for both precision and performance. See {{#crossLink "IslandManager"}}{{/crossLink}}.
* @property {Boolean} islandSplit
* @default true
*/
this.islandSplit = typeof(options.islandSplit)!=="undefined" ? !!options.islandSplit : true;
/**
* Set to true if you want to the world to emit the "impact" event. Turning this off could improve performance.
* @property emitImpactEvent
* @type {Boolean}
* @default true
*/
this.emitImpactEvent = true;
// Id counters
this._constraintIdCounter = 0;
this._bodyIdCounter = 0;
/**
* Fired after the step().
* @event postStep
*/
this.postStepEvent = {
type : "postStep"
};
/**
* Fired when a body is added to the world.
* @event addBody
* @param {Body} body
*/
this.addBodyEvent = {
type : "addBody",
body : null
};
/**
* Fired when a body is removed from the world.
* @event removeBody
* @param {Body} body
*/
this.removeBodyEvent = {
type : "removeBody",
body : null
};
/**
* Fired when a spring is added to the world.
* @event addSpring
* @param {Spring} spring
*/
this.addSpringEvent = {
type : "addSpring",
spring : null
};
/**
* Fired when a first contact is created between two bodies. This event is fired after the step has been done.
* @event impact
* @param {Body} bodyA
* @param {Body} bodyB
*/
this.impactEvent = {
type: "impact",
bodyA : null,
bodyB : null,
shapeA : null,
shapeB : null,
contactEquation : null
};
/**
* Fired after the Broadphase has collected collision pairs in the world.
* Inside the event handler, you can modify the pairs array as you like, to
* prevent collisions between objects that you don't want.
* @event postBroadphase
* @param {Array} pairs An array of collision pairs. If this array is [body1,body2,body3,body4], then the body pairs 1,2 and 3,4 would advance to narrowphase.
*/
this.postBroadphaseEvent = {
type: "postBroadphase",
pairs: null
};
/**
* How to deactivate bodies during simulation. Possible modes are: {{#crossLink "World/NO_SLEEPING:property"}}World.NO_SLEEPING{{/crossLink}}, {{#crossLink "World/BODY_SLEEPING:property"}}World.BODY_SLEEPING{{/crossLink}} and {{#crossLink "World/ISLAND_SLEEPING:property"}}World.ISLAND_SLEEPING{{/crossLink}}.
* If sleeping is enabled, you might need to {{#crossLink "Body/wakeUp:method"}}wake up{{/crossLink}} the bodies if they fall asleep when they shouldn't. If you want to enable sleeping in the world, but want to disable it for a particular body, see {{#crossLink "Body/allowSleep:property"}}Body.allowSleep{{/crossLink}}.
* @property sleepMode
* @type {number}
* @default World.NO_SLEEPING
*/
this.sleepMode = World.NO_SLEEPING;
/**
* Fired when two shapes starts start to overlap. Fired in the narrowphase, during step.
* @event beginContact
* @param {Shape} shapeA
* @param {Shape} shapeB
* @param {Body} bodyA
* @param {Body} bodyB
* @param {Array} contactEquations
*/
this.beginContactEvent = {
type: "beginContact",
shapeA: null,
shapeB: null,
bodyA: null,
bodyB: null,
contactEquations: []
};
/**
* Fired when two shapes stop overlapping, after the narrowphase (during step).
* @event endContact
* @param {Shape} shapeA
* @param {Shape} shapeB
* @param {Body} bodyA
* @param {Body} bodyB
*/
this.endContactEvent = {
type: "endContact",
shapeA: null,
shapeB: null,
bodyA: null,
bodyB: null
};
/**
* Fired just before equations are added to the solver to be solved. Can be used to control what equations goes into the solver.
* @event preSolve
* @param {Array} contactEquations An array of contacts to be solved.
* @param {Array} frictionEquations An array of friction equations to be solved.
*/
this.preSolveEvent = {
type: "preSolve",
contactEquations: null,
frictionEquations: null
};
// For keeping track of overlapping shapes
this.overlappingShapesLastState = { keys:[] };
this.overlappingShapesCurrentState = { keys:[] };
/**
* @property {OverlapKeeper} overlapKeeper
*/
this.overlapKeeper = new OverlapKeeper();
}
World.prototype = new Object(EventEmitter.prototype);
World.prototype.constructor = World;
/**
* Never deactivate bodies.
* @static
* @property {number} NO_SLEEPING
*/
World.NO_SLEEPING = 1;
/**
* Deactivate individual bodies if they are sleepy.
* @static
* @property {number} BODY_SLEEPING
*/
World.BODY_SLEEPING = 2;
/**
* Deactivates bodies that are in contact, if all of them are sleepy. Note that you must enable {{#crossLink "World/islandSplit:property"}}.islandSplit{{/crossLink}} for this to work.
* @static
* @property {number} ISLAND_SLEEPING
*/
World.ISLAND_SLEEPING = 4;
/**
* Add a constraint to the simulation.
*
* @method addConstraint
* @param {Constraint} constraint
* @example
* var constraint = new LockConstraint(bodyA, bodyB);
* world.addConstraint(constraint);
*/
World.prototype.addConstraint = function(constraint){
this.constraints.push(constraint);
};
/**
* Add a ContactMaterial to the simulation.
* @method addContactMaterial
* @param {ContactMaterial} contactMaterial
*/
World.prototype.addContactMaterial = function(contactMaterial){
this.contactMaterials.push(contactMaterial);
};
/**
* Removes a contact material
*
* @method removeContactMaterial
* @param {ContactMaterial} cm
*/
World.prototype.removeContactMaterial = function(cm){
var idx = this.contactMaterials.indexOf(cm);
if(idx!==-1){
Utils.splice(this.contactMaterials,idx,1);
}
};
/**
* Get a contact material given two materials
* @method getContactMaterial
* @param {Material} materialA
* @param {Material} materialB
* @return {ContactMaterial} The matching ContactMaterial, or false on fail.
* @todo Use faster hash map to lookup from material id's
*/
World.prototype.getContactMaterial = function(materialA,materialB){
var cmats = this.contactMaterials;
for(var i=0, N=cmats.length; i!==N; i++){
var cm = cmats[i];
if( (cm.materialA.id === materialA.id) && (cm.materialB.id === materialB.id) ||
(cm.materialA.id === materialB.id) && (cm.materialB.id === materialA.id) ){
return cm;
}
}
return false;
};
/**
* Removes a constraint
*
* @method removeConstraint
* @param {Constraint} constraint
*/
World.prototype.removeConstraint = function(constraint){
var idx = this.constraints.indexOf(constraint);
if(idx!==-1){
Utils.splice(this.constraints,idx,1);
}
};
var step_r = vec2.create(),
step_runit = vec2.create(),
step_u = vec2.create(),
step_f = vec2.create(),
step_fhMinv = vec2.create(),
step_velodt = vec2.create(),
step_mg = vec2.create(),
xiw = vec2.fromValues(0,0),
xjw = vec2.fromValues(0,0),
zero = vec2.fromValues(0,0),
interpvelo = vec2.fromValues(0,0);
/**
* Step the physics world forward in time.
*
* There are two modes. The simple mode is fixed timestepping without interpolation. In this case you only use the first argument. The second case uses interpolation. In that you also provide the time since the function was last used, as well as the maximum fixed timesteps to take.
*
* @method step
* @param {Number} dt The fixed time step size to use.
* @param {Number} [timeSinceLastCalled=0] The time elapsed since the function was last called.
* @param {Number} [maxSubSteps=10] Maximum number of fixed steps to take per function call.
*
* @example
* // Simple fixed timestepping without interpolation
* var fixedTimeStep = 1 / 60;
* var world = new World();
* var body = new Body({ mass: 1 });
* world.addBody(body);
*
* function animate(){
* requestAnimationFrame(animate);
* world.step(fixedTimeStep);
* renderBody(body.position, body.angle);
* }
*
* // Start animation loop
* requestAnimationFrame(animate);
*
* @example
* // Fixed timestepping with interpolation
* var maxSubSteps = 10;
* var lastTimeSeconds;
*
* function animate(t){
* requestAnimationFrame(animate);
* timeSeconds = t / 1000;
* lastTimeSeconds = lastTimeSeconds || timeSeconds;
*
* deltaTime = timeSeconds - lastTimeSeconds;
* world.step(fixedTimeStep, deltaTime, maxSubSteps);
*
* renderBody(body.interpolatedPosition, body.interpolatedAngle);
* }
*
* // Start animation loop
* requestAnimationFrame(animate);
*
* @see http://bulletphysics.org/mediawiki-1.5.8/index.php/Stepping_The_World
*/
World.prototype.step = function(dt,timeSinceLastCalled,maxSubSteps){
maxSubSteps = maxSubSteps || 10;
timeSinceLastCalled = timeSinceLastCalled || 0;
if(timeSinceLastCalled === 0){ // Fixed, simple stepping
this.internalStep(dt);
// Increment time
this.time += dt;
} else {
this.accumulator += timeSinceLastCalled;
var substeps = 0;
while (this.accumulator >= dt && substeps < maxSubSteps) {
// Do fixed steps to catch up
this.internalStep(dt);
this.time += dt;
this.accumulator -= dt;
substeps++;
}
var t = (this.accumulator % dt) / dt;
for(var j=0; j!==this.bodies.length; j++){
var b = this.bodies[j];
vec2.lerp(b.interpolatedPosition, b.previousPosition, b.position, t);
b.interpolatedAngle = b.previousAngle + t * (b.angle - b.previousAngle);
}
}
};
var endOverlaps = [];
/**
* Make a fixed step.
* @method internalStep
* @param {number} dt
* @private
*/
World.prototype.internalStep = function(dt){
this.stepping = true;
var that = this,
Nsprings = this.springs.length,
springs = this.springs,
bodies = this.bodies,
g = this.gravity,
solver = this.solver,
Nbodies = this.bodies.length,
broadphase = this.broadphase,
np = this.narrowphase,
constraints = this.constraints,
t0, t1,
fhMinv = step_fhMinv,
velodt = step_velodt,
mg = step_mg,
scale = vec2.scale,
add = vec2.add,
rotate = vec2.rotate,
islandManager = this.islandManager;
this.overlapKeeper.tick();
this.lastTimeStep = dt;
// Update approximate friction gravity.
if(this.useWorldGravityAsFrictionGravity){
var gravityLen = vec2.length(this.gravity);
if(!(gravityLen === 0 && this.useFrictionGravityOnZeroGravity)){
// Nonzero gravity. Use it.
this.frictionGravity = gravityLen;
}
}
// Add gravity to bodies
if(this.applyGravity){
for(var i=0; i!==Nbodies; i++){
var b = bodies[i],
fi = b.force;
if(b.type !== Body.DYNAMIC || b.sleepState === Body.SLEEPING){
continue;
}
vec2.scale(mg,g,b.mass*b.gravityScale); // F=m*g
add(fi,fi,mg);
}
}
// Add spring forces
if(this.applySpringForces){
for(var i=0; i!==Nsprings; i++){
var s = springs[i];
s.applyForce();
}
}
if(this.applyDamping){
for(var i=0; i!==Nbodies; i++){
var b = bodies[i];
if(b.type === Body.DYNAMIC){
b.applyDamping(dt);
}
}
}
// Broadphase
var result = broadphase.getCollisionPairs(this);
// Remove ignored collision pairs
var ignoredPairs = this.disabledBodyCollisionPairs;
for(var i=ignoredPairs.length-2; i>=0; i-=2){
for(var j=result.length-2; j>=0; j-=2){
if( (ignoredPairs[i] === result[j] && ignoredPairs[i+1] === result[j+1]) ||
(ignoredPairs[i+1] === result[j] && ignoredPairs[i] === result[j+1])){
result.splice(j,2);
}
}
}
// Remove constrained pairs with collideConnected == false
var Nconstraints = constraints.length;
for(i=0; i!==Nconstraints; i++){
var c = constraints[i];
if(!c.collideConnected){
for(var j=result.length-2; j>=0; j-=2){
if( (c.bodyA === result[j] && c.bodyB === result[j+1]) ||
(c.bodyB === result[j] && c.bodyA === result[j+1])){
result.splice(j,2);
}
}
}
}
// postBroadphase event
this.postBroadphaseEvent.pairs = result;
this.emit(this.postBroadphaseEvent);
this.postBroadphaseEvent.pairs = null;
// Narrowphase
np.reset(this);
for(var i=0, Nresults=result.length; i!==Nresults; i+=2){
var bi = result[i],
bj = result[i+1];
// Loop over all shapes of body i
for(var k=0, Nshapesi=bi.shapes.length; k!==Nshapesi; k++){
var si = bi.shapes[k],
xi = si.position,
ai = si.angle;
// All shapes of body j
for(var l=0, Nshapesj=bj.shapes.length; l!==Nshapesj; l++){
var sj = bj.shapes[l],
xj = sj.position,
aj = sj.angle;
var cm = this.defaultContactMaterial;
if(si.material && sj.material){
var tmp = this.getContactMaterial(si.material,sj.material);
if(tmp){
cm = tmp;
}
}
this.runNarrowphase(np,bi,si,xi,ai,bj,sj,xj,aj,cm,this.frictionGravity);
}
}
}
// Wake up bodies
for(var i=0; i!==Nbodies; i++){
var body = bodies[i];
if(body._wakeUpAfterNarrowphase){
body.wakeUp();
body._wakeUpAfterNarrowphase = false;
}
}
// Emit end overlap events
if(this.has('endContact')){
this.overlapKeeper.getEndOverlaps(endOverlaps);
var e = this.endContactEvent;
var l = endOverlaps.length;
while(l--){
var data = endOverlaps[l];
e.shapeA = data.shapeA;
e.shapeB = data.shapeB;
e.bodyA = data.bodyA;
e.bodyB = data.bodyB;
this.emit(e);
}
endOverlaps.length = 0;
}
var preSolveEvent = this.preSolveEvent;
preSolveEvent.contactEquations = np.contactEquations;
preSolveEvent.frictionEquations = np.frictionEquations;
this.emit(preSolveEvent);
preSolveEvent.contactEquations = preSolveEvent.frictionEquations = null;
// update constraint equations
var Nconstraints = constraints.length;
for(i=0; i!==Nconstraints; i++){
constraints[i].update();
}
if(np.contactEquations.length || np.frictionEquations.length || Nconstraints){
if(this.islandSplit){
// Split into islands
islandManager.equations.length = 0;
Utils.appendArray(islandManager.equations, np.contactEquations);
Utils.appendArray(islandManager.equations, np.frictionEquations);
for(i=0; i!==Nconstraints; i++){
Utils.appendArray(islandManager.equations, constraints[i].equations);
}
islandManager.split(this);
for(var i=0; i!==islandManager.islands.length; i++){
var island = islandManager.islands[i];
if(island.equations.length){
solver.solveIsland(dt,island);
}
}
} else {
// Add contact equations to solver
solver.addEquations(np.contactEquations);
solver.addEquations(np.frictionEquations);
// Add user-defined constraint equations
for(i=0; i!==Nconstraints; i++){
solver.addEquations(constraints[i].equations);
}
if(this.solveConstraints){
solver.solve(dt,this);
}
solver.removeAllEquations();
}
}
// Step forward
for(var i=0; i!==Nbodies; i++){
var body = bodies[i];
// if(body.sleepState !== Body.SLEEPING && body.type !== Body.STATIC){
body.integrate(dt);
// }
}
// Reset force
for(var i=0; i!==Nbodies; i++){
bodies[i].setZeroForce();
}
// Emit impact event
if(this.emitImpactEvent && this.has('impact')){
var ev = this.impactEvent;
for(var i=0; i!==np.contactEquations.length; i++){
var eq = np.contactEquations[i];
if(eq.firstImpact){
ev.bodyA = eq.bodyA;
ev.bodyB = eq.bodyB;
ev.shapeA = eq.shapeA;
ev.shapeB = eq.shapeB;
ev.contactEquation = eq;
this.emit(ev);
}
}
}
// Sleeping update
if(this.sleepMode === World.BODY_SLEEPING){
for(i=0; i!==Nbodies; i++){
bodies[i].sleepTick(this.time, false, dt);
}
} else if(this.sleepMode === World.ISLAND_SLEEPING && this.islandSplit){
// Tell all bodies to sleep tick but dont sleep yet
for(i=0; i!==Nbodies; i++){
bodies[i].sleepTick(this.time, true, dt);
}
// Sleep islands
for(var i=0; i<this.islandManager.islands.length; i++){
var island = this.islandManager.islands[i];
if(island.wantsToSleep()){
island.sleep();
}
}
}
this.stepping = false;
// Remove bodies that are scheduled for removal
var bodiesToBeRemoved = this.bodiesToBeRemoved;
for(var i=0; i!==bodiesToBeRemoved.length; i++){
this.removeBody(bodiesToBeRemoved[i]);
}
bodiesToBeRemoved.length = 0;
this.emit(this.postStepEvent);
};
/**
* Runs narrowphase for the shape pair i and j.
* @method runNarrowphase
* @param {Narrowphase} np
* @param {Body} bi
* @param {Shape} si
* @param {Array} xi
* @param {Number} ai
* @param {Body} bj
* @param {Shape} sj
* @param {Array} xj
* @param {Number} aj
* @param {Number} mu
*/
World.prototype.runNarrowphase = function(np,bi,si,xi,ai,bj,sj,xj,aj,cm,glen){
// Check collision groups and masks
if(!((si.collisionGroup & sj.collisionMask) !== 0 && (sj.collisionGroup & si.collisionMask) !== 0)){
return;
}
// Get world position and angle of each shape
vec2.rotate(xiw, xi, bi.angle);
vec2.rotate(xjw, xj, bj.angle);
vec2.add(xiw, xiw, bi.position);
vec2.add(xjw, xjw, bj.position);
var aiw = ai + bi.angle;
var ajw = aj + bj.angle;
np.enableFriction = cm.friction > 0;
np.frictionCoefficient = cm.friction;
var reducedMass;
if(bi.type === Body.STATIC || bi.type === Body.KINEMATIC){
reducedMass = bj.mass;
} else if(bj.type === Body.STATIC || bj.type === Body.KINEMATIC){
reducedMass = bi.mass;
} else {
reducedMass = (bi.mass*bj.mass)/(bi.mass+bj.mass);
}
np.slipForce = cm.friction*glen*reducedMass;
np.restitution = cm.restitution;
np.surfaceVelocity = cm.surfaceVelocity;
np.frictionStiffness = cm.frictionStiffness;
np.frictionRelaxation = cm.frictionRelaxation;
np.stiffness = cm.stiffness;
np.relaxation = cm.relaxation;
np.contactSkinSize = cm.contactSkinSize;
np.enabledEquations = bi.collisionResponse && bj.collisionResponse && si.collisionResponse && sj.collisionResponse;
var resolver = np[si.type | sj.type],
numContacts = 0;
if (resolver) {
var sensor = si.sensor || sj.sensor;
var numFrictionBefore = np.frictionEquations.length;
if (si.type < sj.type) {
numContacts = resolver.call(np, bi,si,xiw,aiw, bj,sj,xjw,ajw, sensor);
} else {
numContacts = resolver.call(np, bj,sj,xjw,ajw, bi,si,xiw,aiw, sensor);
}
var numFrictionEquations = np.frictionEquations.length - numFrictionBefore;
if(numContacts){
if( bi.allowSleep &&
bi.type === Body.DYNAMIC &&
bi.sleepState === Body.SLEEPING &&
bj.sleepState === Body.AWAKE &&
bj.type !== Body.STATIC
){
var speedSquaredB = vec2.squaredLength(bj.velocity) + Math.pow(bj.angularVelocity,2);
var speedLimitSquaredB = Math.pow(bj.sleepSpeedLimit,2);
if(speedSquaredB >= speedLimitSquaredB*2){
bi._wakeUpAfterNarrowphase = true;
}
}
if( bj.allowSleep &&
bj.type === Body.DYNAMIC &&
bj.sleepState === Body.SLEEPING &&
bi.sleepState === Body.AWAKE &&
bi.type !== Body.STATIC
){
var speedSquaredA = vec2.squaredLength(bi.velocity) + Math.pow(bi.angularVelocity,2);
var speedLimitSquaredA = Math.pow(bi.sleepSpeedLimit,2);
if(speedSquaredA >= speedLimitSquaredA*2){
bj._wakeUpAfterNarrowphase = true;
}
}
this.overlapKeeper.setOverlapping(bi, si, bj, sj);
if(this.has('beginContact') && this.overlapKeeper.isNewOverlap(si, sj)){
// Report new shape overlap
var e = this.beginContactEvent;
e.shapeA = si;
e.shapeB = sj;
e.bodyA = bi;
e.bodyB = bj;
// Reset contact equations
e.contactEquations.length = 0;
if(typeof(numContacts)==="number"){
for(var i=np.contactEquations.length-numContacts; i<np.contactEquations.length; i++){
e.contactEquations.push(np.contactEquations[i]);
}
}
this.emit(e);
}
// divide the max friction force by the number of contacts
if(typeof(numContacts)==="number" && numFrictionEquations > 1){ // Why divide by 1?
for(var i=np.frictionEquations.length-numFrictionEquations; i<np.frictionEquations.length; i++){
var f = np.frictionEquations[i];
f.setSlipForce(f.getSlipForce() / numFrictionEquations);
}
}
}
}
};
/**
* Add a spring to the simulation
*
* @method addSpring
* @param {Spring} spring
*/
World.prototype.addSpring = function(spring){
this.springs.push(spring);
var evt = this.addSpringEvent;
evt.spring = spring;
this.emit(evt);
evt.spring = null;
};
/**
* Remove a spring
*
* @method removeSpring
* @param {Spring} spring
*/
World.prototype.removeSpring = function(spring){
var idx = this.springs.indexOf(spring);
if(idx !== -1){
Utils.splice(this.springs,idx,1);
}
};
/**
* Add a body to the simulation
*
* @method addBody
* @param {Body} body
*
* @example
* var world = new World(),
* body = new Body();
* world.addBody(body);
* @todo What if this is done during step?
*/
World.prototype.addBody = function(body){
if(this.bodies.indexOf(body) === -1){
this.bodies.push(body);
body.world = this;
var evt = this.addBodyEvent;
evt.body = body;
this.emit(evt);
evt.body = null;
}
};
/**
* Remove a body from the simulation. If this method is called during step(), the body removal is scheduled to after the step.
*
* @method removeBody
* @param {Body} body
*/
World.prototype.removeBody = function(body){
if(this.stepping){
this.bodiesToBeRemoved.push(body);
} else {
body.world = null;
var idx = this.bodies.indexOf(body);
if(idx!==-1){
Utils.splice(this.bodies,idx,1);
this.removeBodyEvent.body = body;
body.resetConstraintVelocity();
this.emit(this.removeBodyEvent);
this.removeBodyEvent.body = null;
}
}
};
/**
* Get a body by its id.
* @method getBodyById
* @param {number} id
* @return {Body} The body, or false if it was not found.
*/
World.prototype.getBodyById = function(id){
var bodies = this.bodies;
for(var i=0; i<bodies.length; i++){
var b = bodies[i];
if(b.id === id){
return b;
}
}
return false;
};
/**
* Disable collision between two bodies
* @method disableBodyCollision
* @param {Body} bodyA
* @param {Body} bodyB
*/
World.prototype.disableBodyCollision = function(bodyA,bodyB){
this.disabledBodyCollisionPairs.push(bodyA,bodyB);
};
/**
* Enable collisions between the given two bodies
* @method enableBodyCollision
* @param {Body} bodyA
* @param {Body} bodyB
*/
World.prototype.enableBodyCollision = function(bodyA,bodyB){
var pairs = this.disabledBodyCollisionPairs;
for(var i=0; i<pairs.length; i+=2){
if((pairs[i] === bodyA && pairs[i+1] === bodyB) || (pairs[i+1] === bodyA && pairs[i] === bodyB)){
pairs.splice(i,2);
return;
}
}
};
/**
* Resets the World, removes all bodies, constraints and springs.
*
* @method clear
*/
World.prototype.clear = function(){
this.time = 0;
// Remove all solver equations
if(this.solver && this.solver.equations.length){
this.solver.removeAllEquations();
}
// Remove all constraints
var cs = this.constraints;
for(var i=cs.length-1; i>=0; i--){
this.removeConstraint(cs[i]);
}
// Remove all bodies
var bodies = this.bodies;
for(var i=bodies.length-1; i>=0; i--){
this.removeBody(bodies[i]);
}
// Remove all springs
var springs = this.springs;
for(var i=springs.length-1; i>=0; i--){
this.removeSpring(springs[i]);
}
// Remove all contact materials
var cms = this.contactMaterials;
for(var i=cms.length-1; i>=0; i--){
this.removeContactMaterial(cms[i]);
}
World.apply(this);
};
var hitTest_tmp1 = vec2.create(),
hitTest_zero = vec2.fromValues(0,0),
hitTest_tmp2 = vec2.fromValues(0,0);
/**
* Test if a world point overlaps bodies
* @method hitTest
* @param {Array} worldPoint Point to use for intersection tests
* @param {Array} bodies A list of objects to check for intersection
* @param {Number} precision Used for matching against particles and lines. Adds some margin to these infinitesimal objects.
* @return {Array} Array of bodies that overlap the point
* @todo Should use an api similar to the raycast function
* @todo Should probably implement a .containsPoint method for all shapes. Would be more efficient
* @todo Should use the broadphase
*/
World.prototype.hitTest = function(worldPoint,bodies,precision){
precision = precision || 0;
// Create a dummy particle body with a particle shape to test against the bodies
var pb = new Body({ position:worldPoint }),
ps = new Particle(),
px = worldPoint,
pa = 0,
x = hitTest_tmp1,
zero = hitTest_zero,
tmp = hitTest_tmp2;
pb.addShape(ps);
var n = this.narrowphase,
result = [];
// Check bodies
for(var i=0, N=bodies.length; i!==N; i++){
var b = bodies[i];
for(var j=0, NS=b.shapes.length; j!==NS; j++){
var s = b.shapes[j];
// Get shape world position + angle
vec2.rotate(x, s.position, b.angle);
vec2.add(x, x, b.position);
var a = s.angle + b.angle;
if( (s instanceof Circle && n.circleParticle (b,s,x,a, pb,ps,px,pa, true)) ||
(s instanceof Convex && n.particleConvex (pb,ps,px,pa, b,s,x,a, true)) ||
(s instanceof Plane && n.particlePlane (pb,ps,px,pa, b,s,x,a, true)) ||
(s instanceof Capsule && n.particleCapsule (pb,ps,px,pa, b,s,x,a, true)) ||
(s instanceof Particle && vec2.squaredLength(vec2.sub(tmp,x,worldPoint)) < precision*precision)
){
result.push(b);
}
}
}
return result;
};
/**
* Set the stiffness for all equations and contact materials.
* @method setGlobalStiffness
* @param {Number} stiffness
*/
World.prototype.setGlobalStiffness = function(stiffness){
// Set for all constraints
var constraints = this.constraints;
for(var i=0; i !== constraints.length; i++){
var c = constraints[i];
for(var j=0; j !== c.equations.length; j++){
var eq = c.equations[j];
eq.stiffness = stiffness;
eq.needsUpdate = true;
}
}
// Set for all contact materials
var contactMaterials = this.contactMaterials;
for(var i=0; i !== contactMaterials.length; i++){
var c = contactMaterials[i];
c.stiffness = c.frictionStiffness = stiffness;
}
// Set for default contact material
var c = this.defaultContactMaterial;
c.stiffness = c.frictionStiffness = stiffness;
};
/**
* Set the relaxation for all equations and contact materials.
* @method setGlobalRelaxation
* @param {Number} relaxation
*/
World.prototype.setGlobalRelaxation = function(relaxation){
// Set for all constraints
for(var i=0; i !== this.constraints.length; i++){
var c = this.constraints[i];
for(var j=0; j !== c.equations.length; j++){
var eq = c.equations[j];
eq.relaxation = relaxation;
eq.needsUpdate = true;
}
}
// Set for all contact materials
for(var i=0; i !== this.contactMaterials.length; i++){
var c = this.contactMaterials[i];
c.relaxation = c.frictionRelaxation = relaxation;
}
// Set for default contact material
var c = this.defaultContactMaterial;
c.relaxation = c.frictionRelaxation = relaxation;
};
var tmpAABB = new AABB();
var tmpArray = [];
/**
* Ray cast against all bodies in the world.
* @method raycast
* @param {RaycastResult} result
* @param {Ray} ray
* @return {boolean} True if any body was hit.
*
* @example
* var ray = new Ray({
* mode: Ray.CLOSEST, // or ANY
* from: [0, 0],
* to: [10, 0],
* });
* var result = new RaycastResult();
* world.raycast(result, ray);
*
* // Get the hit point
* var hitPoint = vec2.create();
* result.getHitPoint(hitPoint, ray);
* console.log('Hit point: ', hitPoint[0], hitPoint[1], ' at distance ' + result.getHitDistance(ray));
*
* @example
* var ray = new Ray({
* mode: Ray.ALL,
* from: [0, 0],
* to: [10, 0],
* callback: function(result){
*
* // Print some info about the hit
* console.log('Hit body and shape: ', result.body, result.shape);
*
* // Get the hit point
* var hitPoint = vec2.create();
* result.getHitPoint(hitPoint, ray);
* console.log('Hit point: ', hitPoint[0], hitPoint[1], ' at distance ' + result.getHitDistance(ray));
*
* // If you are happy with the hits you got this far, you can stop the traversal here:
* result.stop();
* }
* });
* var result = new RaycastResult();
* world.raycast(result, ray);
*/
World.prototype.raycast = function(result, ray){
// Get all bodies within the ray AABB
ray.getAABB(tmpAABB);
this.broadphase.aabbQuery(this, tmpAABB, tmpArray);
ray.intersectBodies(result, tmpArray);
tmpArray.length = 0;
return result.hasHit();
};
