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liabru-matter-js/build/matter.js
2014-02-19 14:15:05 +00:00

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JavaScript

/**
* matter.js 0.5.0 2014-02-19
* http://brm.io/matter-js/
* License: MIT
*/
/**
* The MIT License (MIT)
*
* Copyright (c) 2014 Liam Brummitt
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
(function() {
var Matter = {};
// Begin Matter namespace closure
// All Matter modules are included below during build
// Outro.js then closes at the end of the file
// Begin src/body/Body.js
var Body = {};
(function() {
var _nextId = 0,
_nextGroupId = 1;
Body.create = function(options) {
var defaults = {
id: Body.nextId(),
angle: 0,
position: { x: 0, y: 0 },
force: { x: 0, y: 0 },
torque: 0,
positionImpulse: { x: 0, y: 0 },
speed: 0,
angularSpeed: 0,
velocity: { x: 0, y: 0 },
angularVelocity: 0,
isStatic: false,
isSleeping: false,
motion: 0,
sleepThreshold: 60,
density: 0.001,
restitution: 0,
friction: 0.1,
frictionAir: 0.01,
path: 'L 0 0 L 40 0 L 40 40 L 0 40',
fillStyle: options.isStatic ? '#eeeeee' : Common.choose(['#556270', '#4ECDC4', '#C7F464', '#FF6B6B', '#C44D58']),
lineWidth: 1.5,
groupId: 0,
slop: 0.05
};
var body = Common.extend(defaults, options);
Body.updateProperties(body);
return body;
};
Body.nextId = function() {
return _nextId++;
};
Body.nextGroupId = function() {
return _nextGroupId++;
};
Body.updateProperties = function(body) {
// calculated properties
body.vertices = body.vertices || Vertices.fromPath(body.path);
body.axes = body.axes || Axes.fromVertices(body.vertices);
body.area = Vertices.area(body.vertices);
body.bounds = Bounds.create(body.vertices);
body.mass = body.mass || (body.density * body.area);
body.inverseMass = 1 / body.mass;
body.inertia = body.inertia || Vertices.inertia(body.vertices, body.mass);
body.inverseInertia = 1 / body.inertia;
body.positionPrev = body.positionPrev || { x: body.position.x, y: body.position.y };
body.anglePrev = body.anglePrev || body.angle;
body.strokeStyle = body.strokeStyle || Common.shadeColor(body.fillStyle, -20);
// update geometry
Vertices.create(body.vertices, body);
var centre = Vertices.centre(body.vertices);
Vertices.translate(body.vertices, body.position);
Vertices.translate(body.vertices, centre, -1);
Vertices.rotate(body.vertices, body.angle, body.position);
Axes.rotate(body.axes, body.angle);
Bounds.update(body.bounds, body.vertices, body.velocity);
if (body.isStatic) {
body.restitution = 0;
body.friction = 1;
body.mass = body.inertia = body.density = Infinity;
body.inverseMass = body.inverseInertia = 0;
body.lineWidth = 1;
}
Sleeping.set(body, body.isSleeping);
};
Body.resetForcesAll = function(bodies, gravity) {
for (var i = 0; i < bodies.length; i++) {
var body = bodies[i];
if (body.isStatic || body.isSleeping)
continue;
// reset force buffers
body.force.x = 0;
body.force.y = 0;
body.torque = 0;
// apply gravity
body.force.y += body.mass * gravity.y * 0.001;
body.force.x += body.mass * gravity.x * 0.001;
}
};
Body.updateAll = function(bodies, deltaTime, correction, worldBounds) {
for (var i = 0; i < bodies.length; i++) {
var body = bodies[i];
if (body.isStatic || body.isSleeping)
continue;
// don't update out of world bodies
// TODO: viewports
if (body.bounds.max.x < worldBounds.min.x || body.bounds.min.x > worldBounds.max.x
|| body.bounds.max.y < worldBounds.min.y || body.bounds.min.y > worldBounds.max.y)
continue;
Body.update(body, deltaTime, correction);
}
};
Body.update = function(body, deltaTime, correction) {
var deltaTimeSquared = deltaTime * deltaTime;
// from the previous step
var frictionAir = 1 - body.frictionAir,
velocityPrevX = body.position.x - body.positionPrev.x,
velocityPrevY = body.position.y - body.positionPrev.y;
// update velocity with verlet integration
body.velocity.x = (velocityPrevX * frictionAir * correction) + (body.force.x / body.mass) * deltaTimeSquared;
body.velocity.y = (velocityPrevY * frictionAir * correction) + (body.force.y / body.mass) * deltaTimeSquared;
body.positionPrev.x = body.position.x;
body.positionPrev.y = body.position.y;
body.position.x += body.velocity.x;
body.position.y += body.velocity.y;
// update angular velocity with verlet integration
body.angularVelocity = ((body.angle - body.anglePrev) * frictionAir * correction) + (body.torque / body.inertia) * deltaTimeSquared;
body.anglePrev = body.angle;
body.angle += body.angularVelocity;
// track speed and acceleration
body.speed = Vector.magnitude(body.velocity);
body.angularSpeed = Math.abs(body.angularVelocity);
// transform the body geometry
Vertices.translate(body.vertices, body.velocity);
Vertices.rotate(body.vertices, body.angularVelocity, body.position);
Axes.rotate(body.axes, body.angularVelocity);
Bounds.update(body.bounds, body.vertices, body.velocity);
};
Body.applyForce = function(body, position, force) {
body.force.x += force.x;
body.force.y += force.y;
var offset = { x: position.x - body.position.x, y: position.y - body.position.y };
body.torque += (offset.x * force.y - offset.y * force.x) * body.inverseInertia;
};
Body.translate = function(body, translation) {
body.positionPrev.x += translation.x;
body.positionPrev.y += translation.y;
body.position.x += translation.x;
body.position.y += translation.y;
Vertices.translate(body.vertices, translation);
Bounds.update(body.bounds, body.vertices, body.velocity);
};
Body.rotate = function(body, angle) {
body.anglePrev += angle;
body.angle += angle;
Vertices.rotate(body.vertices, angle, body.position);
Axes.rotate(body.axes, angle);
Bounds.update(body.bounds, body.vertices, body.velocity);
};
})();
; // End src/body/Body.js
// Begin src/body/Composite.js
// TODO: composite translate, rotate
var Composite = {};
(function() {
Composite.create = function(options) {
return Common.extend({ bodies: [], constraints: [], composites: [] }, options);
};
Composite.add = function(compositeA, compositeB) {
if (compositeA.bodies && compositeB.bodies)
compositeA.bodies = compositeA.bodies.concat(compositeB.bodies);
if (compositeA.constraints && compositeB.constraints)
compositeA.constraints = compositeA.constraints.concat(compositeB.constraints);
if (compositeA.composites && compositeB.composites)
compositeA.composites = compositeA.composites.concat(compositeB.composites);
return compositeA;
};
Composite.addBody = function(composite, body) {
composite.bodies = composite.bodies || [];
composite.bodies.push(body);
return composite;
};
Composite.addConstraint = function(composite, constraint) {
composite.constraints = composite.constraints || [];
composite.constraints.push(constraint);
return composite;
};
})();
; // End src/body/Composite.js
// Begin src/body/World.js
var World = {};
(function() {
World.create = function(options) {
var defaults = {
gravity: { x: 0, y: 1 },
bodies: [],
constraints: [],
bounds: {
min: { x: 0, y: 0 },
max: { x: 800, y: 600 }
}
};
return Common.extend(defaults, options);
};
World.clear = function(world, keepStatic) {
world.bodies = keepStatic ? world.bodies.filter(function(body) { return body.isStatic; }) : [];
world.constraints = [];
};
// world is a composite body
// see src/module/Outro.js for these aliases:
// World.addComposite = Composite.add;
// World.addBody = Composite.addBody;
// World.addConstraint = Composite.addConstraint;
})();
; // End src/body/World.js
// Begin src/collision/Contact.js
var Contact = {};
(function() {
Contact.create = function(vertex) {
return {
id: Contact.id(vertex),
vertex: vertex,
normalImpulse: 0,
tangentImpulse: 0
};
};
Contact.id = function(vertex) {
return vertex.body.id + '_' + vertex.index;
};
})();
; // End src/collision/Contact.js
// Begin src/collision/Detector.js
// TODO: speculative contacts
var Detector = {};
(function() {
Detector.collisions = function(pairs, metrics) {
var collisions = [];
for (var i = 0; i < pairs.length; i++) {
var bodyA = pairs[i][0],
bodyB = pairs[i][1];
// NOTE: could share a function for the below, but may drop performance?
if (bodyA.groupId && bodyB.groupId && bodyA.groupId === bodyB.groupId)
continue;
if ((bodyA.isStatic || bodyA.isSleeping) && (bodyB.isStatic || bodyB.isSleeping))
continue;
metrics.midphaseTests += 1;
// mid phase
if (Bounds.overlaps(bodyA.bounds, bodyB.bounds)) {
// narrow phase
var collision = SAT.collides(bodyA, bodyB);
metrics.narrowphaseTests += 1;
if (collision.collided) {
collisions.push(collision);
metrics.narrowDetections += 1;
}
}
}
return collisions;
};
Detector.bruteForce = function(bodies, metrics) {
var collisions = [];
for (var i = 0; i < bodies.length; i++) {
for (var j = i + 1; j < bodies.length; j++) {
var bodyA = bodies[i],
bodyB = bodies[j];
// NOTE: could share a function for the below, but may drop performance?
if (bodyA.groupId && bodyB.groupId && bodyA.groupId === bodyB.groupId)
continue;
if ((bodyA.isStatic || bodyA.isSleeping) && (bodyB.isStatic || bodyB.isSleeping))
continue;
metrics.midphaseTests += 1;
// mid phase
if (Bounds.overlaps(bodyA.bounds, bodyB.bounds)) {
// narrow phase
var collision = SAT.collides(bodyA, bodyB);
metrics.narrowphaseTests += 1;
if (collision.collided) {
collisions.push(collision);
metrics.narrowDetections += 1;
}
}
}
}
return collisions;
};
})();
; // End src/collision/Detector.js
// Begin src/collision/Grid.js
var Grid = {};
(function() {
Grid.create = function(bucketWidth, bucketHeight) {
return {
buckets: {},
pairs: {},
pairsList: [],
bucketWidth: bucketWidth || 48,
bucketHeight: bucketHeight || 48
};
};
Grid.update = function(grid, bodies, engine, forceUpdate) {
var i, col, row,
world = engine.world,
buckets = grid.buckets,
bucket,
bucketId,
metrics = engine.metrics,
gridChanged = false;
metrics.broadphaseTests = 0;
for (i = 0; i < bodies.length; i++) {
var body = bodies[i];
if (body.isSleeping)
continue;
// don't update out of world bodies
if (body.bounds.max.x < 0 || body.bounds.min.x > world.bounds.width
|| body.bounds.max.y < 0 || body.bounds.min.y > world.bounds.height)
continue;
var newRegion = _getRegion(grid, body);
// if the body has changed grid region
if (!body.region || newRegion.id !== body.region.id || forceUpdate) {
metrics.broadphaseTests += 1;
if (!body.region || forceUpdate)
body.region = newRegion;
var union = _regionUnion(newRegion, body.region);
// update grid buckets affected by region change
// iterate over the union of both regions
for (col = union.startCol; col <= union.endCol; col++) {
for (row = union.startRow; row <= union.endRow; row++) {
bucketId = _getBucketId(col, row);
bucket = buckets[bucketId];
var isInsideNewRegion = (col >= newRegion.startCol && col <= newRegion.endCol
&& row >= newRegion.startRow && row <= newRegion.endRow);
var isInsideOldRegion = (col >= body.region.startCol && col <= body.region.endCol
&& row >= body.region.startRow && row <= body.region.endRow);
// remove from old region buckets
if (!isInsideNewRegion && isInsideOldRegion) {
if (isInsideOldRegion) {
if (bucket)
_bucketRemoveBody(grid, bucket, body);
}
}
// add to new region buckets
if (body.region === newRegion || (isInsideNewRegion && !isInsideOldRegion) || forceUpdate) {
if (!bucket)
bucket = _createBucket(buckets, bucketId);
_bucketAddBody(grid, bucket, body);
}
}
}
// set the new region
body.region = newRegion;
// flag changes so we can update pairs
gridChanged = true;
}
}
// update pairs list only if pairs changed (i.e. a body changed region)
if (gridChanged)
grid.pairsList = _createActivePairsList(grid);
};
Grid.clear = function(grid) {
grid.buckets = {};
grid.pairs = {};
grid.pairsList = [];
};
var _regionUnion = function(regionA, regionB) {
var startCol = Math.min(regionA.startCol, regionB.startCol),
endCol = Math.max(regionA.endCol, regionB.endCol),
startRow = Math.min(regionA.startRow, regionB.startRow),
endRow = Math.max(regionA.endRow, regionB.endRow);
return _createRegion(startCol, endCol, startRow, endRow);
};
var _getRegion = function(grid, body) {
var bounds = body.bounds,
startCol = Math.floor(bounds.min.x / grid.bucketWidth),
endCol = Math.floor(bounds.max.x / grid.bucketWidth),
startRow = Math.floor(bounds.min.y / grid.bucketHeight),
endRow = Math.floor(bounds.max.y / grid.bucketHeight);
return _createRegion(startCol, endCol, startRow, endRow);
};
var _createRegion = function(startCol, endCol, startRow, endRow) {
return {
id: startCol + ',' + endCol + ',' + startRow + ',' + endRow,
startCol: startCol,
endCol: endCol,
startRow: startRow,
endRow: endRow
};
};
var _getBucketId = function(column, row) {
return column + ',' + row;
};
var _createBucket = function(buckets, bucketId) {
var bucket = buckets[bucketId] = [];
return bucket;
};
var _bucketAddBody = function(grid, bucket, body) {
// add new pairs
for (var i = 0; i < bucket.length; i++) {
var bodyB = bucket[i];
if (body.id === bodyB.id || (body.isStatic && bodyB.isStatic))
continue;
// keep track of the number of buckets the pair exists in
// important for Grid.update to work
var pairId = _getPairId(body, bodyB);
if (grid.pairs[pairId]) {
grid.pairs[pairId][2] += 1;
} else {
grid.pairs[pairId] = [body, bodyB, 1];
}
}
// add to bodies (after pairs, otherwise pairs with self)
bucket.push(body);
};
var _bucketRemoveBody = function(grid, bucket, body) {
// remove from bodies
for (var i = 0; i < bucket.length; i++) {
var bodyB = bucket[i];
// when position of body in bucket array is found, remove it
if (bodyB.id === body.id) {
bucket.splice(i, 1);
continue;
} else {
// keep track of the number of buckets the pair exists in
// important for Grid.update to work
var pairId = _getPairId(body, bodyB);
if (grid.pairs[pairId]) {
var pairCount = grid.pairs[pairId][2];
grid.pairs[pairId][2] = pairCount > 0 ? pairCount - 1 : 0;
}
}
}
};
var _getPairId = function(bodyA, bodyB) {
if (bodyA.id < bodyB.id) {
return bodyA.id + ',' + bodyB.id;
} else {
return bodyB.id + ',' + bodyA.id;
}
};
var _createActivePairsList = function(grid) {
var pairKeys,
pair,
pairs = [];
// grid.pairs is used as a hashmap
pairKeys = Common.keys(grid.pairs);
// iterate over grid.pairs
for (var k = 0; k < pairKeys.length; k++) {
pair = grid.pairs[pairKeys[k]];
// if pair exists in at least one bucket
// it is a pair that needs further collision testing so push it
if (pair[2] > 0)
pairs.push(pair);
}
return pairs;
};
})();
; // End src/collision/Grid.js
// Begin src/collision/Manager.js
var Manager = {};
(function() {
var _pairMaxIdleLife = 500;
Manager.updatePairs = function(pairs, pairsList, candidatePairs, metrics, detector) {
var i;
// first set all pairs inactive
for (i = 0; i < pairsList.length; i++) {
var pair = pairsList[i];
Pair.setActive(pair, false);
}
// detect collisions in current step
var pairsUpdated = false,
collisions = detector(candidatePairs, metrics);
// set collision pairs to active, or create if pair is new
for (i = 0; i < collisions.length; i++) {
var collision = collisions[i],
pairId = Pair.id(collision.bodyA, collision.bodyB);
if (pairId in pairs) {
Pair.update(pairs[pairId], collision);
} else {
pairs[pairId] = Pair.create(collision);
pairsUpdated = true;
}
}
return pairsUpdated;
};
Manager.removeOldPairs = function(pairs, pairsList) {
var timeNow = Common.now(),
pairsRemoved = false,
i;
for (i = 0; i < pairsList.length; i++) {
var pair = pairsList[i],
collision = pair.collision;
// never remove sleeping pairs
if (collision.bodyA.isSleeping || collision.bodyB.isSleeping) {
pair.timestamp = timeNow;
continue;
}
// if pair is inactive for too long, remove it
if (timeNow - pair.timestamp > _pairMaxIdleLife) {
delete pairs[pair.id];
pairsRemoved = true;
}
}
return pairsRemoved;
};
})();
; // End src/collision/Manager.js
// Begin src/collision/Pair.js
var Pair = {};
(function() {
Pair.create = function(collision) {
var bodyA = collision.bodyA,
bodyB = collision.bodyB;
var pair = {
id: Pair.id(bodyA, bodyB),
contacts: {},
activeContacts: [],
separation: 0,
isActive: true,
timestamp: Common.now(),
inverseMass: bodyA.inverseMass + bodyB.inverseMass,
friction: Math.min(bodyA.friction, bodyB.friction),
restitution: Math.max(bodyA.restitution, bodyB.restitution),
slop: Math.max(bodyA.slop, bodyB.slop)
};
Pair.update(pair, collision);
return pair;
};
Pair.update = function(pair, collision) {
var contacts = pair.contacts,
supports = collision.supports,
activeContacts = [];
pair.collision = collision;
if (collision.collided) {
for (var i = 0; i < supports.length; i++) {
var support = supports[i],
contactId = Contact.id(support);
if (contactId in contacts) {
activeContacts.push(contacts[contactId]);
} else {
activeContacts.push(contacts[contactId] = Contact.create(support));
}
}
pair.activeContacts = activeContacts;
pair.separation = collision.depth;
Pair.setActive(pair, true);
} else {
Pair.setActive(pair, false);
}
};
Pair.setActive = function(pair, isActive) {
if (isActive) {
pair.isActive = true;
pair.timestamp = Common.now();
} else {
pair.isActive = false;
pair.activeContacts = [];
}
};
Pair.id = function(bodyA, bodyB) {
if (bodyA.id < bodyB.id) {
return bodyA.id + '_' + bodyB.id;
} else {
return bodyB.id + '_' + bodyA.id;
}
};
})();
; // End src/collision/Pair.js
// Begin src/collision/Resolver.js
var Resolver = {};
(function() {
var _restingThresh = 4,
_positionDampen = 0.2,
_positionWarming = 0.6;
Resolver.solvePosition = function(pairs) {
var i,
pair,
collision,
bodyA,
bodyB,
vertex,
vertexCorrected,
normal,
bodyBtoA;
// find impulses required to resolve penetration
for (i = 0; i < pairs.length; i++) {
pair = pairs[i];
if (!pair.isActive)
continue;
collision = pair.collision;
bodyA = collision.bodyA;
bodyB = collision.bodyB;
vertex = collision.supports[0];
vertexCorrected = collision.supportCorrected;
normal = collision.normal;
// get current separation between body edges involved in collision
bodyBtoA = Vector.sub(Vector.add(bodyB.positionImpulse, vertex),
Vector.add(bodyA.positionImpulse, vertexCorrected));
pair.separation = Vector.dot(normal, bodyBtoA);
}
for (i = 0; i < pairs.length; i++) {
pair = pairs[i];
if (!pair.isActive)
continue;
collision = pair.collision;
bodyA = collision.bodyA;
bodyB = collision.bodyB;
normal = collision.normal;
positionImpulse = (pair.separation * _positionDampen) - pair.slop;
if (bodyA.isStatic || bodyB.isStatic)
positionImpulse *= 2;
if (!(bodyA.isStatic || bodyA.isSleeping)) {
bodyA.positionImpulse.x += normal.x * positionImpulse;
bodyA.positionImpulse.y += normal.y * positionImpulse;
}
if (!(bodyB.isStatic || bodyB.isSleeping)) {
bodyB.positionImpulse.x -= normal.x * positionImpulse;
bodyB.positionImpulse.y -= normal.y * positionImpulse;
}
}
};
Resolver.postSolvePosition = function(bodies) {
for (var i = 0; i < bodies.length; i++) {
var body = bodies[i];
if (body.positionImpulse.x !== 0 || body.positionImpulse.y !== 0) {
// move the body without changing velocity
body.position.x += body.positionImpulse.x;
body.position.y += body.positionImpulse.y;
body.positionPrev.x += body.positionImpulse.x;
body.positionPrev.y += body.positionImpulse.y;
// update body geometry
Vertices.translate(body.vertices, body.positionImpulse);
Bounds.update(body.bounds, body.vertices, body.velocity);
// dampen accumulator to warm the next step
body.positionImpulse.x *= _positionWarming;
body.positionImpulse.y *= _positionWarming;
}
}
};
Resolver.preSolveVelocity = function(pairs) {
var impulse = {},
i,
j,
pair,
contacts,
collision,
bodyA,
bodyB,
normal,
tangent,
contact,
contactVertex,
normalImpulse,
tangentImpulse,
offset;
for (i = 0; i < pairs.length; i++) {
pair = pairs[i];
if (!pair.isActive)
continue;
contacts = pair.activeContacts;
collision = pair.collision;
bodyA = collision.bodyA;
bodyB = collision.bodyB;
normal = collision.normal;
tangent = collision.tangent;
// resolve each contact
for (j = 0; j < contacts.length; j++) {
contact = contacts[j];
contactVertex = contact.vertex;
normalImpulse = contact.normalImpulse;
tangentImpulse = contact.tangentImpulse;
// total impulse from contact
impulse.x = (normal.x * normalImpulse) + (tangent.x * tangentImpulse);
impulse.y = (normal.y * normalImpulse) + (tangent.y * tangentImpulse);
// apply impulse from contact
if (!(bodyA.isStatic || bodyA.isSleeping)) {
offset = Vector.sub(contactVertex, bodyA.position);
bodyA.positionPrev.x += impulse.x * bodyA.inverseMass;
bodyA.positionPrev.y += impulse.y * bodyA.inverseMass;
bodyA.anglePrev += Vector.cross(offset, impulse) * bodyA.inverseInertia;
}
if (!(bodyB.isStatic || bodyB.isSleeping)) {
offset = Vector.sub(contactVertex, bodyB.position);
bodyB.positionPrev.x -= impulse.x * bodyB.inverseMass;
bodyB.positionPrev.y -= impulse.y * bodyB.inverseMass;
bodyB.anglePrev -= Vector.cross(offset, impulse) * bodyB.inverseInertia;
}
}
}
};
Resolver.solveVelocity = function(pairs) {
var impulse = {};
for (var i = 0; i < pairs.length; i++) {
var pair = pairs[i];
if (!pair.isActive)
continue;
var collision = pair.collision,
bodyA = collision.bodyA,
bodyB = collision.bodyB,
normal = collision.normal,
tangent = collision.tangent,
contacts = pair.activeContacts,
contactShare = 1 / contacts.length;
// update body velocities
bodyA.velocity.x = bodyA.position.x - bodyA.positionPrev.x;
bodyA.velocity.y = bodyA.position.y - bodyA.positionPrev.y;
bodyB.velocity.x = bodyB.position.x - bodyB.positionPrev.x;
bodyB.velocity.y = bodyB.position.y - bodyB.positionPrev.y;
bodyA.angularVelocity = bodyA.angle - bodyA.anglePrev;
bodyB.angularVelocity = bodyB.angle - bodyB.anglePrev;
// resolve each contact
for (var j = 0; j < contacts.length; j++) {
var contact = contacts[j],
contactVertex = contact.vertex,
offsetA = Vector.sub(contactVertex, bodyA.position),
offsetB = Vector.sub(contactVertex, bodyB.position),
velocityPointA = Vector.add(bodyA.velocity, Vector.mult(Vector.perp(offsetA), bodyA.angularVelocity)),
velocityPointB = Vector.add(bodyB.velocity, Vector.mult(Vector.perp(offsetB), bodyB.angularVelocity)),
relativeVelocity = Vector.sub(velocityPointA, velocityPointB),
normalVelocity = Vector.dot(normal, relativeVelocity);
var tangentVelocity = Vector.dot(tangent, relativeVelocity),
tangentSpeed = Math.abs(tangentVelocity),
tangentVelocityDirection = Common.sign(tangentVelocity);
// raw impulses
var normalImpulse = (1 + pair.restitution) * normalVelocity,
normalForce = Common.clamp(pair.separation + normalVelocity, 0, 1);
// coulomb friction
var tangentImpulse = tangentVelocity;
if (tangentSpeed > normalForce * pair.friction)
tangentImpulse = normalForce * pair.friction * tangentVelocityDirection;
// modify impulses accounting for mass, inertia and offset
var oAcN = Vector.cross(offsetA, normal),
oBcN = Vector.cross(offsetB, normal),
share = contactShare / (pair.inverseMass + bodyA.inverseInertia * oAcN * oAcN + bodyB.inverseInertia * oBcN * oBcN);
normalImpulse *= share;
tangentImpulse *= share;
// handle high velocity and resting collisions separately
if (normalVelocity < 0 && normalVelocity * normalVelocity > _restingThresh) {
// high velocity so clear cached contact impulse
contact.normalImpulse = 0;
contact.tangentImpulse = 0;
} else {
// solve resting collision constraints using Erin Catto's method (GDC08)
// impulse constraint, tends to 0
var contactNormalImpulse = contact.normalImpulse;
contact.normalImpulse = Math.min(contact.normalImpulse + normalImpulse, 0);
normalImpulse = contact.normalImpulse - contactNormalImpulse;
// tangent impulse, tends to -maxFriction or maxFriction
var contactTangentImpulse = contact.tangentImpulse;
contact.tangentImpulse = Common.clamp(contact.tangentImpulse + tangentImpulse, -tangentSpeed, tangentSpeed);
tangentImpulse = contact.tangentImpulse - contactTangentImpulse;
}
// total impulse from contact
impulse.x = (normal.x * normalImpulse) + (tangent.x * tangentImpulse);
impulse.y = (normal.y * normalImpulse) + (tangent.y * tangentImpulse);
// apply impulse from contact
if (!(bodyA.isStatic || bodyA.isSleeping)) {
bodyA.positionPrev.x += impulse.x * bodyA.inverseMass;
bodyA.positionPrev.y += impulse.y * bodyA.inverseMass;
bodyA.anglePrev += Vector.cross(offsetA, impulse) * bodyA.inverseInertia;
}
if (!(bodyB.isStatic || bodyB.isSleeping)) {
bodyB.positionPrev.x -= impulse.x * bodyB.inverseMass;
bodyB.positionPrev.y -= impulse.y * bodyB.inverseMass;
bodyB.anglePrev -= Vector.cross(offsetB, impulse) * bodyB.inverseInertia;
}
}
}
};
})();
; // End src/collision/Resolver.js
// Begin src/collision/SAT.js
// TODO: true circles and curves
// TODO: cache the previously found axis and body, and start there first for faster early out
var SAT = {};
(function() {
SAT.collides = function(bodyA, bodyB) {
var overlapAB,
overlapBA,
minOverlap,
collision = { collided: false, bodyA: bodyA, bodyB: bodyB};
overlapAB = _overlapAxes(bodyA.vertices, bodyB.vertices, bodyA.axes);
if (overlapAB.overlap === 0)
return collision;
overlapBA = _overlapAxes(bodyB.vertices, bodyA.vertices, bodyB.axes);
if (overlapBA.overlap === 0)
return collision;
if (overlapAB.overlap < overlapBA.overlap) {
minOverlap = overlapAB;
} else {
minOverlap = overlapBA;
collision.bodyA = bodyB;
collision.bodyB = bodyA;
}
collision.collided = true;
collision.normal = minOverlap.axis;
collision.depth = minOverlap.overlap;
bodyA = collision.bodyA;
bodyB = collision.bodyB;
// ensure normal is facing away from bodyA
if (Vector.dot(collision.normal, Vector.sub(bodyB.position, bodyA.position)) > 0)
collision.normal = Vector.neg(collision.normal);
collision.tangent = Vector.perp(collision.normal);
collision.penetration = {
x: collision.normal.x * collision.depth,
y: collision.normal.y * collision.depth
};
// find support points, there is always either exactly one or two
var verticesB = _findSupports(bodyA, bodyB, collision.normal),
supports = [verticesB[0]];
if (Vertices.contains(bodyA.vertices, verticesB[1])) {
supports.push(verticesB[1]);
} else {
var verticesA = _findSupports(bodyB, bodyA, Vector.neg(collision.normal));
if (Vertices.contains(bodyB.vertices, verticesA[0])) {
supports.push(verticesA[0]);
}
if (supports.length < 2 && Vertices.contains(bodyB.vertices, verticesA[1])) {
supports.push(verticesA[1]);
}
}
collision.supports = supports;
collision.supportCorrected = Vector.sub(verticesB[0], collision.penetration);
return collision;
};
var _overlapAxes = function(verticesA, verticesB, axes) {
var projectionA = {},
projectionB = {},
result = { overlap: Number.MAX_VALUE },
overlap,
axis;
for (var i = 0; i < axes.length; i++) {
axis = axes[i];
_projectToAxis(projectionA, verticesA, axis);
_projectToAxis(projectionB, verticesB, axis);
overlap = projectionA.min < projectionB.min
? projectionA.max - projectionB.min
: projectionB.max - projectionA.min;
if (overlap <= 0)
return { overlap: 0 };
if (overlap < result.overlap) {
result.overlap = overlap;
result.axis = axis;
}
}
return result;
};
var _projectToAxis = function(projection, vertices, axis) {
var min = Vector.dot(vertices[0], axis),
max = min;
for (var i = 1; i < vertices.length; i += 1) {
var dot = Vector.dot(vertices[i], axis);
if (dot > max) {
max = dot;
} else if (dot < min) {
min = dot;
}
}
projection.min = min;
projection.max = max;
};
var _findSupports = function(bodyA, bodyB, normal) {
var nearestDistance = Number.MAX_VALUE,
vertexToBody = { x: 0, y: 0 },
vertices = bodyB.vertices,
bodyAPosition = bodyA.position,
distance,
vertex,
vertexA = vertices[0],
vertexB = vertices[1];
// find closest vertex on bodyB
for (var i = 0; i < vertices.length; i++) {
vertex = vertices[i];
vertexToBody.x = vertex.x - bodyAPosition.x;
vertexToBody.y = vertex.y - bodyAPosition.y;
distance = -Vector.dot(normal, vertexToBody);
if (distance < nearestDistance) {
nearestDistance = distance;
vertexA = vertex;
}
}
// find next closest vertex using the two connected to it
var prevIndex = vertexA.index - 1 >= 0 ? vertexA.index - 1 : vertices.length - 1;
vertex = vertices[prevIndex];
vertexToBody.x = vertex.x - bodyAPosition.x;
vertexToBody.y = vertex.y - bodyAPosition.y;
nearestDistance = -Vector.dot(normal, vertexToBody);
vertexB = vertex;
var nextIndex = (vertexA.index + 1) % vertices.length;
vertex = vertices[nextIndex];
vertexToBody.x = vertex.x - bodyAPosition.x;
vertexToBody.y = vertex.y - bodyAPosition.y;
distance = -Vector.dot(normal, vertexToBody);
if (distance < nearestDistance) {
nearestDistance = distance;
vertexB = vertex;
}
return [vertexA, vertexB];
};
})();
; // End src/collision/SAT.js
// Begin src/constraint/Constraint.js
// TODO: fix instabillity issues with torque
// TODO: linked constraints
// TODO: breakable constraints
// TODO: collidable constraints
// TODO: allow constrained bodies to sleep
// TODO: handle 0 length constraints properly
// TODO: impulse caching and warming
var Constraint = {};
(function() {
var _minLength = 0.000001;
Constraint.create = function(options) {
var constraint = options;
// if bodies defined but no points, use body centre
if (constraint.bodyA && !constraint.pointA)
constraint.pointA = { x: 0, y: 0 };
if (constraint.bodyB && !constraint.pointB)
constraint.pointB = { x: 0, y: 0 };
// calculate static length using initial world space points
var initialPointA = constraint.bodyA ? Vector.add(constraint.bodyA.position, constraint.pointA) : constraint.pointA,
initialPointB = constraint.bodyB ? Vector.add(constraint.bodyB.position, constraint.pointB) : constraint.pointB,
length = Vector.magnitude(Vector.sub(initialPointA, initialPointB));
constraint.length = constraint.length || length || _minLength;
// option defaults
constraint.lineWidth = constraint.lineWidth || 2;
constraint.strokeStyle = constraint.strokeStyle || '#666';
constraint.stiffness = constraint.stiffness || 1;
constraint.angularStiffness = constraint.angularStiffness || 0;
constraint.angleA = constraint.bodyA ? constraint.bodyA.angle : constraint.angleA;
constraint.angleB = constraint.bodyB ? constraint.bodyB.angle : constraint.angleB;
return constraint;
};
Constraint.updateAll = function(constraints) {
for (var i = 0; i < constraints.length; i++) {
Constraint.update(constraints[i]);
}
};
Constraint.update = function(constraint) {
var bodyA = constraint.bodyA,
bodyB = constraint.bodyB,
pointA = constraint.pointA,
pointB = constraint.pointB;
// update reference angle
if (bodyA && !bodyA.isStatic) {
constraint.pointA = Vector.rotate(pointA, bodyA.angle - constraint.angleA);
constraint.angleA = bodyA.angle;
}
// update reference angle
if (bodyB && !bodyB.isStatic) {
constraint.pointB = Vector.rotate(pointB, bodyB.angle - constraint.angleB);
constraint.angleB = bodyB.angle;
}
var pointAWorld = pointA,
pointBWorld = pointB;
if (bodyA) pointAWorld = Vector.add(bodyA.position, pointA);
if (bodyB) pointBWorld = Vector.add(bodyB.position, pointB);
if (!pointAWorld || !pointBWorld)
return;
var delta = Vector.sub(pointAWorld, pointBWorld),
currentLength = Vector.magnitude(delta);
// prevent singularity
if (currentLength === 0)
currentLength = _minLength;
// solve distance constraint with Gauss-Siedel method
var difference = (currentLength - constraint.length) / currentLength,
normal = Vector.div(delta, currentLength),
force = Vector.mult(delta, difference * 0.5 * constraint.stiffness);
var velocityPointA,
velocityPointB,
offsetA,
offsetB,
oAn,
oBn,
bodyADenom,
bodyBDenom;
if (bodyA && !bodyA.isStatic) {
// point body offset
offsetA = {
x: pointAWorld.x - bodyA.position.x + force.x,
y: pointAWorld.y - bodyA.position.y + force.y
};
// update velocity
bodyA.velocity.x = bodyA.position.x - bodyA.positionPrev.x;
bodyA.velocity.y = bodyA.position.y - bodyA.positionPrev.y;
bodyA.angularVelocity = bodyA.angle - bodyA.anglePrev;
// find point velocity and body mass
velocityPointA = Vector.add(bodyA.velocity, Vector.mult(Vector.perp(offsetA), bodyA.angularVelocity));
oAn = Vector.dot(offsetA, normal);
bodyADenom = bodyA.inverseMass + bodyA.inverseInertia * oAn * oAn;
} else {
velocityPointA = { x: 0, y: 0 };
bodyADenom = bodyA ? bodyA.inverseMass : 0;
}
if (bodyB && !bodyB.isStatic) {
// point body offset
offsetB = {
x: pointBWorld.x - bodyB.position.x - force.x,
y: pointBWorld.y - bodyB.position.y - force.y
};
// update velocity
bodyB.velocity.x = bodyB.position.x - bodyB.positionPrev.x;
bodyB.velocity.y = bodyB.position.y - bodyB.positionPrev.y;
bodyB.angularVelocity = bodyB.angle - bodyB.anglePrev;
// find point velocity and body mass
velocityPointB = Vector.add(bodyB.velocity, Vector.mult(Vector.perp(offsetB), bodyB.angularVelocity));
oBn = Vector.dot(offsetB, normal);
bodyBDenom = bodyB.inverseMass + bodyB.inverseInertia * oBn * oBn;
} else {
velocityPointB = { x: 0, y: 0 };
bodyBDenom = bodyB ? bodyB.inverseMass : 0;
}
var relativeVelocity = Vector.sub(velocityPointB, velocityPointA),
normalImpulse = Vector.dot(normal, relativeVelocity) / (bodyADenom + bodyBDenom);
if (normalImpulse > 0) normalImpulse = 0;
var normalVelocity = {
x: normal.x * normalImpulse,
y: normal.y * normalImpulse
};
var torque;
if (bodyA && !bodyA.isStatic) {
torque = Vector.cross(offsetA, normalVelocity) * bodyA.inverseInertia * (1 - constraint.angularStiffness);
Sleeping.set(bodyA, false);
// clamp to prevent instabillity
// TODO: solve this properlly
torque = Common.clamp(torque, -0.01, 0.01);
// apply forces
bodyA.position.x -= force.x;
bodyA.position.y -= force.y;
bodyA.angle += torque;
// update geometry
Vertices.translate(bodyA.vertices, force, -1);
Vertices.rotate(bodyA.vertices, torque, bodyA.position);
Axes.rotate(bodyA.axes, torque);
Bounds.update(bodyA.bounds, bodyA.vertices, bodyA.velocity);
}
if (bodyB && !bodyB.isStatic) {
torque = Vector.cross(offsetB, normalVelocity) * bodyB.inverseInertia * (1 - constraint.angularStiffness);
Sleeping.set(bodyB, false);
// clamp to prevent instabillity
// TODO: solve this properlly
torque = Common.clamp(torque, -0.01, 0.01);
// apply forces
bodyB.position.x += force.x;
bodyB.position.y += force.y;
bodyB.angle -= torque;
// update geometry
Vertices.translate(bodyB.vertices, force);
Vertices.rotate(bodyB.vertices, -torque, bodyB.position);
Axes.rotate(bodyB.axes, -torque);
Bounds.update(bodyB.bounds, bodyB.vertices, bodyB.velocity);
}
};
})();
; // End src/constraint/Constraint.js
// Begin src/constraint/MouseConstraint.js
var MouseConstraint = {};
(function() {
MouseConstraint.create = function(mouse) {
var constraint = Constraint.create({
pointA: mouse.position,
pointB: { x: 0, y: 0 },
length: 0.01,
stiffness: 0.1,
angularStiffness: 1,
strokeStyle: 'lightgreen',
lineWidth: 3
});
return {
mouse: mouse,
dragBody: null,
dragPoint: null,
constraints: [constraint]
};
};
MouseConstraint.update = function(mouseConstraint, bodies) {
var mouse = mouseConstraint.mouse,
constraint = mouseConstraint.constraints[0];
if (mouse.button === 0 || mouse.button === 2) {
if (!constraint.bodyB) {
for (var i = 0; i < bodies.length; i++) {
var body = bodies[i];
if (Bounds.contains(body.bounds, mouse.position)
&& Vertices.contains(body.vertices, mouse.position)) {
constraint.pointA = mouse.position;
constraint.bodyB = body;
constraint.pointB = { x: mouse.position.x - body.position.x, y: mouse.position.y - body.position.y };
constraint.angleB = body.angle;
Sleeping.set(body, false);
}
}
}
} else {
constraint.bodyB = null;
constraint.pointB = null;
}
if (constraint.bodyB) {
Sleeping.set(constraint.bodyB, false);
constraint.pointA = mouse.position;
}
};
})();
; // End src/constraint/MouseConstraint.js
// Begin src/core/Common.js
var Common = {};
(function() {
Common.extend = function(obj) {
var args = Array.prototype.slice.call(arguments, 1);
for (var i = 0; i < args.length; i++) {
var source = args[i];
if (source) {
for (var prop in source) {
if (source[prop].constructor === Object) {
if (!obj[prop] || obj[prop].constructor === Object) {
obj[prop] = obj[prop] || {};
Common.extend(obj[prop], source[prop]);
} else {
obj[prop] = source[prop];
}
} else {
obj[prop] = source[prop];
}
}
}
}
return obj;
};
Common.keys = function(obj) {
if (Object.keys)
return Object.keys(obj);
// avoid hasOwnProperty for performance
var keys = [];
for (var key in obj)
keys.push(key);
return keys;
};
Common.values = function(obj) {
var values = [];
if (Object.keys) {
var keys = Object.keys(obj);
for (var i = 0; i < keys.length; i++) {
values.push(obj[keys[i]]);
}
return values;
}
// avoid hasOwnProperty for performance
for (var key in obj)
values.push(obj[key]);
return values;
};
Common.shadeColor = function(color, percent) {
// http://stackoverflow.com/questions/5560248/programmatically-lighten-or-darken-a-hex-color
var colorInteger = parseInt(color.slice(1),16),
amount = Math.round(2.55 * percent),
R = (colorInteger >> 16) + amount,
B = (colorInteger >> 8 & 0x00FF) + amount,
G = (colorInteger & 0x0000FF) + amount;
return "#" + (0x1000000 + (R < 255 ? R < 1 ? 0 : R :255) * 0x10000
+ (B < 255 ? B < 1 ? 0 : B : 255) * 0x100
+ (G < 255 ? G < 1 ? 0 : G : 255)).toString(16).slice(1);
};
Common.shuffle = function(array) {
for (var i = array.length - 1; i > 0; i--) {
var j = Math.floor(Math.random() * (i + 1));
var temp = array[i];
array[i] = array[j];
array[j] = temp;
}
return array;
};
Common.choose = function(choices) {
return choices[Math.floor(Math.random() * choices.length)];
};
Common.isElement = function(obj) {
// http://stackoverflow.com/questions/384286/javascript-isdom-how-do-you-check-if-a-javascript-object-is-a-dom-object
try {
return obj instanceof HTMLElement;
}
catch(e){
return (typeof obj==="object") &&
(obj.nodeType===1) && (typeof obj.style === "object") &&
(typeof obj.ownerDocument ==="object");
}
};
Common.clamp = function(value, min, max) {
if (value < min)
return min;
if (value > max)
return max;
return value;
};
Common.sign = function(value) {
return value < 0 ? -1 : 1;
};
Common.now = Date.now || function() {
// http://stackoverflow.com/questions/221294/how-do-you-get-a-timestamp-in-javascript
return +(new Date());
};
Common.random = function(min, max) {
return min + Math.random() * (max - min);
};
})();
; // End src/core/Common.js
// Begin src/core/Engine.js
// TODO: multiple event handlers, before & after handlers
// TODO: viewports
// TODO: frameskipping
var Engine = {};
(function() {
var _fps = 60,
_deltaSampleSize = 8,
_delta = 1000 / _fps;
var _requestAnimationFrame = window.requestAnimationFrame || window.webkitRequestAnimationFrame
|| window.mozRequestAnimationFrame || window.msRequestAnimationFrame
|| function(callback){ window.setTimeout(function() { callback(Common.now()); }, _delta); };
Engine.create = function(element, options) {
var defaults = {
enabled: true,
positionIterations: 6,
velocityIterations: 4,
constraintIterations: 1,
pairs: {},
pairsList: [],
enableSleeping: false,
timeScale: 1,
input: {},
timing: {
fps: _fps,
timestamp: 0,
delta: _delta,
correction: 1,
deltaMin: 1000 / _fps,
deltaMax: 1000 / (_fps * 0.5)
}
};
var engine = Common.extend(defaults, options);
engine = Common.isElement(element) ? (engine || {}) : element;
// create default renderer only if no custom renderer set
// but still allow engine.render.engine to pass through if set
if (!engine.render || (engine.render && !engine.render.controller)) {
engine.render = Render.create(engine.render);
if (Common.isElement(element))
element.appendChild(engine.render.canvas);
}
engine.world = World.create(engine.world);
engine.metrics = engine.metrics || Metrics.create();
engine.input.mouse = engine.input.mouse || Mouse.create(engine.render.canvas);
engine.mouseConstraint = engine.mouseConstraint || MouseConstraint.create(engine.input.mouse);
World.addComposite(engine.world, engine.mouseConstraint);
engine.broadphase = engine.broadphase || {
current: 'grid',
grid: {
controller: Grid,
instance: Grid.create(),
detector: Detector.collisions
},
bruteForce: {
detector: Detector.bruteForce
}
};
engine.events = {
tick: function(engine) {
Engine.update(engine, engine.timing.delta, engine.timing.correction);
},
render: function(engine) {
if (engine.render.options.enabled)
engine.render.controller.world(engine);
}
};
return engine;
};
Engine.run = function(engine) {
var timing = engine.timing,
delta,
counterTimestamp = 0,
frameCounter = 0,
deltaHistory = [];
(function render(timestamp){
_requestAnimationFrame(render);
if (!engine.enabled)
return;
delta = (timestamp - timing.timestamp) || _delta;
// optimistically filter delta over a few frames, to improve stability
deltaHistory.push(delta);
deltaHistory = deltaHistory.slice(-_deltaSampleSize);
delta = Math.min.apply(null, deltaHistory);
// limit delta
delta = delta < engine.timing.deltaMin ? engine.timing.deltaMin : delta;
delta = delta > engine.timing.deltaMax ? engine.timing.deltaMax : delta;
timing.timestamp = timestamp;
timing.correction = delta / timing.delta;
timing.delta = delta;
frameCounter += 1;
if (timestamp - counterTimestamp >= 1000) {
timing.fps = frameCounter * ((timestamp - counterTimestamp) / 1000);
counterTimestamp = timestamp;
frameCounter = 0;
}
engine.events.tick(engine);
engine.events.render(engine);
})();
};
Engine.update = function(engine, delta, correction) {
var world = engine.world,
broadphase = engine.broadphase[engine.broadphase.current],
broadphasePairs = [],
i;
Body.resetForcesAll(world.bodies, world.gravity);
Metrics.reset(engine.metrics);
MouseConstraint.update(engine.mouseConstraint, world.bodies, engine.input);
Body.updateAll(world.bodies, delta * engine.timeScale, correction, world.bounds);
for (i = 0; i < engine.constraintIterations; i++) {
Constraint.updateAll(world.constraints);
}
if (broadphase.controller) {
broadphase.controller.update(broadphase.instance, world.bodies, engine);
broadphasePairs = broadphase.instance.pairsList;
} else {
broadphasePairs = world.bodies;
}
var pairsUpdated = Manager.updatePairs(engine.pairs, engine.pairsList, broadphasePairs, engine.metrics, broadphase.detector),
pairsRemoved = Manager.removeOldPairs(engine.pairs, engine.pairsList);
if (pairsUpdated || pairsRemoved)
engine.pairsList = Common.values(engine.pairs);
// wake up bodies involved in collisions
if (engine.enableSleeping)
Sleeping.afterCollisions(engine.pairsList);
// iteratively resolve velocity between collisions
Resolver.preSolveVelocity(engine.pairsList);
for (i = 0; i < engine.velocityIterations; i++) {
Resolver.solveVelocity(engine.pairsList);
}
// iteratively resolve position between collisions
for (i = 0; i < engine.positionIterations; i++) {
Resolver.solvePosition(engine.pairsList);
}
Resolver.postSolvePosition(world.bodies);
if (engine.enableSleeping)
Sleeping.update(world.bodies);
Metrics.update(engine.metrics, engine);
return engine;
};
Engine.merge = function(engineA, engineB) {
Common.extend(engineA, engineB);
if (engineB.world) {
engineA.world = engineB.world;
Engine.clear(engineA);
var bodies = engineA.world.bodies;
for (var i = 0; i < bodies.length; i++) {
var body = bodies[i];
Sleeping.set(body, false);
body.id = Body.nextId();
}
var broadphase = engineA.broadphase[engineA.broadphase.current];
if (broadphase.controller === Grid) {
var grid = broadphase.instance;
Grid.clear(grid);
Grid.update(grid, engineA.world.bodies, engineA, true);
}
}
};
Engine.clear = function(engine) {
var world = engine.world;
engine.pairs = {};
engine.pairsList = [];
World.addComposite(engine.world, engine.mouseConstraint);
var broadphase = engine.broadphase[engine.broadphase.current];
if (broadphase.controller === Grid)
Grid.clear(broadphase.instance);
if (broadphase.controller) {
broadphase.controller.update(broadphase.instance, world.bodies, engine, true);
}
};
})();
; // End src/core/Engine.js
// Begin src/core/Metrics.js
var Metrics = {};
(function() {
Metrics.create = function() {
return {
narrowDetections: 0,
narrowphaseTests: 0,
midphaseTests: 0,
broadphaseTests: 0,
narrowEff: 0.0001,
midEff: 0.0001,
broadEff: 0.0001,
collisions: 0,
buckets: 0,
bodies: 0,
pairs: 0
};
};
Metrics.reset = function(metrics) {
metrics.narrowDetections = 0;
metrics.narrowphaseTests = 0;
metrics.midphaseTests = 0;
metrics.broadphaseTests = 0;
metrics.narrowEff = 0;
metrics.midEff = 0;
metrics.broadEff = 0;
metrics.collisions = 0;
metrics.buckets = 0;
metrics.pairs = 0;
metrics.bodies = 0;
};
Metrics.update = function(metrics, engine) {
var world = engine.world,
broadphase = engine.broadphase[engine.broadphase.current];
metrics.collisions = metrics.narrowDetections;
metrics.pairs = engine.pairsList.length;
metrics.bodies = world.bodies.length;
metrics.midEff = (metrics.narrowDetections / (metrics.midphaseTests || 1)).toFixed(2);
metrics.narrowEff = (metrics.narrowDetections / (metrics.narrowphaseTests || 1)).toFixed(2);
metrics.broadEff = (1 - (metrics.broadphaseTests / (world.bodies.length || 1))).toFixed(2);
if (broadphase.instance)
metrics.buckets = Common.keys(broadphase.instance.buckets).length;
};
})();
; // End src/core/Metrics.js
// Begin src/core/Mouse.js
var Mouse;
(function() {
Mouse = function(element) {
var mouse = this;
element = element || document.body;
this.position = { x: 0, y: 0 };
this.mousedownPosition = { x: 0, y: 0 };
this.mouseupPosition = { x: 0, y: 0 };
this.button = -1;
var mousemove = function(event) {
var position = _getRelativeMousePosition(event, element),
touches = event.changedTouches;
if (touches) {
mouse.button = 0;
event.preventDefault();
}
mouse.position = position;
};
var mousedown = function(event) {
var position = _getRelativeMousePosition(event, element),
touches = event.changedTouches;
if (touches) {
mouse.button = 0;
event.preventDefault();
} else {
mouse.button = event.button;
}
mouse.position = mouse.mousedownPosition = position;
};
var mouseup = function(event) {
var position = _getRelativeMousePosition(event, element),
touches = event.changedTouches;
if (touches) {
event.preventDefault();
}
mouse.button = -1;
mouse.position = mouse.mouseupPosition = position;
};
element.addEventListener('mousemove', mousemove);
element.addEventListener('mousedown', mousedown);
element.addEventListener('mouseup', mouseup);
element.addEventListener('touchmove', mousemove);
element.addEventListener('touchstart', mousedown);
element.addEventListener('touchend', mouseup);
};
Mouse.create = function(element) {
return new Mouse(element);
};
var _getRelativeMousePosition = function(event, element) {
var elementBounds = element.getBoundingClientRect(),
scrollX = (window.pageXOffset !== undefined) ? window.pageXOffset : (document.documentElement || document.body.parentNode || document.body).scrollLeft,
scrollY = (window.pageYOffset !== undefined) ? window.pageYOffset : (document.documentElement || document.body.parentNode || document.body).scrollTop,
touches = event.changedTouches,
x, y;
if (touches) {
x = touches[0].pageX - elementBounds.left - scrollX;
y = touches[0].pageY - elementBounds.top - scrollY;
} else {
x = event.pageX - elementBounds.left - scrollX;
y = event.pageY - elementBounds.top - scrollY;
}
return {
x: x / (element.clientWidth / element.width),
y: y / (element.clientHeight / element.height)
};
};
})();
; // End src/core/Mouse.js
// Begin src/core/Sleeping.js
var Sleeping = {};
(function() {
var _motionWakeThreshold = 0.18,
_motionSleepThreshold = 0.08,
_minBias = 0.9;
Sleeping.update = function(bodies) {
// update bodies sleeping status
for (var i = 0; i < bodies.length; i++) {
var body = bodies[i],
motion = body.speed * body.speed + body.angularSpeed * body.angularSpeed;
var minMotion = Math.min(body.motion, motion),
maxMotion = Math.max(body.motion, motion);
// biased average motion estimation between frames
body.motion = _minBias * minMotion + (1 - _minBias) * maxMotion;
if (body.sleepThreshold > 0 && body.motion < _motionSleepThreshold) {
body.sleepCounter += 1;
if (body.sleepCounter >= body.sleepThreshold)
Sleeping.set(body, true);
} else if (body.sleepCounter > 0) {
body.sleepCounter -= 1;
}
}
};
Sleeping.afterCollisions = function(pairs) {
// wake up bodies involved in collisions
for (var i = 0; i < pairs.length; i++) {
var pair = pairs[i],
collision = pair.collision,
bodyA = collision.bodyA,
bodyB = collision.bodyB;
if ((bodyA.isSleeping && bodyB.isSleeping) || bodyA.isStatic || bodyB.isStatic)
continue;
if (bodyA.isSleeping || bodyB.isSleeping) {
var sleepingBody = (bodyA.isSleeping && !bodyA.isStatic) ? bodyA : bodyB,
movingBody = sleepingBody === bodyA ? bodyB : bodyA;
if (!sleepingBody.isStatic && movingBody.motion > _motionWakeThreshold) {
Sleeping.set(sleepingBody, false);
}
}
}
};
Sleeping.set = function(body, isSleeping) {
if (isSleeping) {
body.isSleeping = true;
body.sleepCounter = body.sleepThreshold;
body.positionImpulse.x = 0;
body.positionImpulse.y = 0;
body.positionPrev.x = body.position.x;
body.positionPrev.y = body.position.y;
body.anglePrev = body.angle;
body.speed = 0;
body.angularSpeed = 0;
body.motion = 0;
} else {
body.isSleeping = false;
body.sleepCounter = 0;
}
};
})();
; // End src/core/Sleeping.js
// Begin src/factory/Bodies.js
// TODO: true circle bodies
var Bodies = {};
(function() {
Bodies.rectangle = function(x, y, width, height, options) {
options = options || {};
var rectangle = {
position: { x: x, y: y },
path: 'L 0 0 L ' + width + ' 0 L ' + width + ' ' + height + ' L 0 ' + height
};
return Body.create(Common.extend({}, rectangle, options));
};
Bodies.trapezoid = function(x, y, width, height, slope, options) {
options = options || {};
slope *= 0.5;
var roof = (1 - (slope * 2)) * width;
var x1 = width * slope,
x2 = x1 + roof,
x3 = x2 + x1;
var trapezoid = {
position: { x: x, y: y },
path: 'L 0 0 L ' + x1 + ' ' + (-height) + ' L ' + x2 + ' ' + (-height) + ' L ' + x3 + ' 0'
};
return Body.create(Common.extend({}, trapezoid, options));
};
Bodies.circle = function(x, y, radius, options, maxSides) {
options = options || {};
// approximate circles with polygons until true circles implemented in SAT
maxSides = maxSides || 25;
var sides = Math.ceil(Math.max(10, Math.min(maxSides, radius)));
// optimisation: always use even number of sides (half the number of unique axes)
if (sides % 2 === 1)
sides += 1;
// flag for better rendering
options.circleRadius = radius;
return Bodies.polygon(x, y, sides, radius, options);
};
Bodies.polygon = function(x, y, sides, radius, options) {
options = options || {};
if (sides < 3)
return Bodies.circle(x, y, radius, options);
var theta = 2 * Math.PI / sides,
path = '',
offset = theta * 0.5;
for (var i = 0; i < sides; i += 1) {
var angle = offset + (i * theta),
xx = Math.cos(angle) * radius,
yy = Math.sin(angle) * radius;
path += 'L ' + xx.toFixed(3) + ' ' + yy.toFixed(3) + ' ';
}
var polygon = {
position: { x: x, y: y },
path: path
};
return Body.create(Common.extend({}, polygon, options));
};
})();
; // End src/factory/Bodies.js
// Begin src/factory/Composites.js
var Composites = {};
(function() {
Composites.stack = function(xx, yy, columns, rows, columnGap, rowGap, callback) {
var stack = Composite.create(),
x = xx,
y = yy,
lastBody,
i = 0;
for (var row = 0; row < rows; row++) {
var maxHeight = 0;
for (var column = 0; column < columns; column++) {
var body = callback(x, y, column, row, lastBody, i);
if (body) {
var bodyHeight = body.bounds.max.y - body.bounds.min.y,
bodyWidth = body.bounds.max.x - body.bounds.min.x;
if (bodyHeight > maxHeight)
maxHeight = bodyHeight;
Body.translate(body, { x: bodyWidth * 0.5, y: bodyHeight * 0.5 });
x = body.bounds.max.x + columnGap;
Composite.addBody(stack, body);
lastBody = body;
i += 1;
}
}
y += maxHeight + rowGap;
x = xx;
}
return stack;
};
Composites.chain = function(composite, xOffsetA, yOffsetA, xOffsetB, yOffsetB, options) {
var bodies = composite.bodies;
for (var i = 1; i < bodies.length; i++) {
var bodyA = bodies[i - 1],
bodyB = bodies[i],
bodyAHeight = bodyA.bounds.max.y - bodyA.bounds.min.y,
bodyAWidth = bodyA.bounds.max.x - bodyA.bounds.min.x,
bodyBHeight = bodyB.bounds.max.y - bodyB.bounds.min.y,
bodyBWidth = bodyB.bounds.max.x - bodyB.bounds.min.x;
var defaults = {
bodyA: bodyA,
pointA: { x: bodyAWidth * xOffsetA, y: bodyAHeight * yOffsetA },
bodyB: bodyB,
pointB: { x: bodyBWidth * xOffsetB, y: bodyBHeight * yOffsetB }
};
var constraint = Common.extend(defaults, options);
Composite.addConstraint(composite, Constraint.create(constraint));
}
return composite;
};
Composites.pyramid = function(xx, yy, columns, rows, columnGap, rowGap, callback) {
return Composites.stack(xx, yy, columns, rows, columnGap, rowGap, function(x, y, column, row, lastBody, i) {
var actualRows = Math.min(rows, Math.ceil(columns / 2)),
lastBodyWidth = lastBody ? lastBody.bounds.max.x - lastBody.bounds.min.x : 0;
if (row > actualRows)
return;
// reverse row order
row = actualRows - row;
var start = row,
end = columns - 1 - row;
if (column < start || column > end)
return;
// retroactively fix the first body's position, since width was unknown
if (i === 1) {
Body.translate(lastBody, { x: (column + (columns % 2 === 1 ? 1 : -1)) * lastBodyWidth, y: 0 });
}
var xOffset = lastBody ? column * lastBodyWidth : 0;
return callback(xx + xOffset + column * columnGap, y, column, row, lastBody, i);
});
};
Composites.newtonsCradle = function(xx, yy, number, size, length) {
var newtonsCradle = Composite.create();
for (var i = 0; i < number; i++) {
var separation = 1.9,
circle = Bodies.circle(xx + i * (size * separation), yy + length, size,
{ restitution: 1, friction: 0, frictionAir: 0.0001, slop: 0.01 }),
constraint = Constraint.create({ pointA: { x: xx + i * (size * separation), y: yy }, bodyB: circle });
Composite.addBody(newtonsCradle, circle);
Composite.addConstraint(newtonsCradle, constraint);
}
return newtonsCradle;
};
Composites.car = function(xx, yy, width, height, wheelSize) {
var groupId = Body.nextGroupId(),
wheelBase = -20,
wheelAOffset = -width * 0.5 + wheelBase,
wheelBOffset = width * 0.5 - wheelBase,
wheelYOffset = 0;
var car = Composite.create(),
body = Bodies.trapezoid(xx, yy, width, height, 0.3, { groupId: groupId, friction: 0.01 });
var wheelA = Bodies.circle(xx + wheelAOffset, yy + wheelYOffset, wheelSize, {
groupId: groupId,
restitution: 0.5,
friction: 0.9,
density: 0.01
});
var wheelB = Bodies.circle(xx + wheelBOffset, yy + wheelYOffset, wheelSize, {
groupId: groupId,
restitution: 0.5,
friction: 0.9,
density: 0.01
});
var axelA = Constraint.create({
bodyA: body,
pointA: { x: wheelAOffset, y: wheelYOffset },
bodyB: wheelA,
stiffness: 0.5
});
var axelB = Constraint.create({
bodyA: body,
pointA: { x: wheelBOffset, y: wheelYOffset },
bodyB: wheelB,
stiffness: 0.5
});
Composite.addBody(car, body);
Composite.addBody(car, wheelA);
Composite.addBody(car, wheelB);
Composite.addConstraint(car, axelA);
Composite.addConstraint(car, axelB);
return car;
};
})();
; // End src/factory/Composites.js
// Begin src/geometry/Axes.js
var Axes = {};
(function() {
Axes.fromVertices = function(vertices) {
var axes = {};
// find the unique axes, using edge normal gradients
for (var i = 0; i < vertices.length; i++) {
var j = (i + 1) % vertices.length,
normal = Vector.normalise({
x: vertices[j].y - vertices[i].y,
y: vertices[i].x - vertices[j].x
}),
gradient = (normal.y === 0) ? Infinity : (normal.x / normal.y);
// limit precision
gradient = gradient.toFixed(3).toString();
axes[gradient] = normal;
}
return Common.values(axes);
};
Axes.rotate = function(axes, angle) {
if (angle === 0)
return;
var cos = Math.cos(angle),
sin = Math.sin(angle);
for (var i = 0; i < axes.length; i++) {
var axis = axes[i],
xx;
xx = axis.x * cos - axis.y * sin;
axis.y = axis.x * sin + axis.y * cos;
axis.x = xx;
}
};
})();
; // End src/geometry/Axes.js
// Begin src/geometry/Bounds.js
var Bounds = {};
(function() {
Bounds.create = function(vertices) {
var bounds = {
min: { x: 0, y: 0 },
max: { x: 0, y: 0 }
};
Bounds.update(bounds, vertices);
return bounds;
};
Bounds.update = function(bounds, vertices, velocity) {
bounds.min.x = Number.MAX_VALUE;
bounds.max.x = Number.MIN_VALUE;
bounds.min.y = Number.MAX_VALUE;
bounds.max.y = Number.MIN_VALUE;
for (var i = 0; i < vertices.length; i++) {
var vertex = vertices[i];
if (vertex.x > bounds.max.x) bounds.max.x = vertex.x;
if (vertex.x < bounds.min.x) bounds.min.x = vertex.x;
if (vertex.y > bounds.max.y) bounds.max.y = vertex.y;
if (vertex.y < bounds.min.y) bounds.min.y = vertex.y;
}
if (velocity) {
if (velocity.x > 0) {
bounds.max.x += velocity.x;
} else {
bounds.min.x += velocity.x;
}
if (velocity.y > 0) {
bounds.max.y += velocity.y;
} else {
bounds.min.y += velocity.y;
}
}
};
Bounds.contains = function(bounds, point) {
return point.x >= bounds.min.x && point.x <= bounds.max.x
&& point.y >= bounds.min.y && point.y <= bounds.max.y;
};
Bounds.overlaps = function(boundsA, boundsB) {
return (boundsA.min.x <= boundsB.max.x && boundsA.max.x >= boundsB.min.x
&& boundsA.max.y >= boundsB.min.y && boundsA.min.y <= boundsB.max.y);
};
})();
; // End src/geometry/Bounds.js
// Begin src/geometry/Vector.js
// TODO: consider params for reusing vector objects
var Vector = {};
(function() {
Vector.magnitude = function(vector) {
return Math.sqrt((vector.x * vector.x) + (vector.y * vector.y));
};
Vector.magnitudeSquared = function(vector) {
return (vector.x * vector.x) + (vector.y * vector.y);
};
Vector.rotate = function(vector, angle) {
var cos = Math.cos(angle), sin = Math.sin(angle);
return {
x: vector.x * cos - vector.y * sin,
y: vector.x * sin + vector.y * cos
};
};
Vector.rotateAbout = function(vector, angle, point) {
var cos = Math.cos(angle), sin = Math.sin(angle);
return {
x: point.x + ((vector.x - point.x) * cos - (vector.y - point.y) * sin),
y: point.y + ((vector.x - point.x) * sin + (vector.y - point.y) * cos)
};
};
Vector.normalise = function(vector) {
var magnitude = Vector.magnitude(vector);
if (magnitude === 0)
return { x: 0, y: 0 };
return { x: vector.x / magnitude, y: vector.y / magnitude };
};
Vector.dot = function(vectorA, vectorB) {
return (vectorA.x * vectorB.x) + (vectorA.y * vectorB.y);
};
Vector.cross = function(vectorA, vectorB) {
return (vectorA.x * vectorB.y) - (vectorA.y * vectorB.x);
};
Vector.add = function(vectorA, vectorB) {
return { x: vectorA.x + vectorB.x, y: vectorA.y + vectorB.y };
};
Vector.sub = function(vectorA, vectorB) {
return { x: vectorA.x - vectorB.x, y: vectorA.y - vectorB.y };
};
Vector.mult = function(vector, scalar) {
return { x: vector.x * scalar, y: vector.y * scalar };
};
Vector.div = function(vector, scalar) {
return { x: vector.x / scalar, y: vector.y / scalar };
};
Vector.perp = function(vector, negate) {
negate = negate === true ? -1 : 1;
return { x: negate * -vector.y, y: negate * vector.x };
};
Vector.neg = function(vector) {
return { x: -vector.x, y: -vector.y };
};
})();
; // End src/geometry/Vector.js
// Begin src/geometry/Vertices.js
// TODO: convex decomposition - http://mnbayazit.com/406/bayazit
var Vertices = {};
(function() {
Vertices.create = function(vertices, body) {
for (var i = 0; i < vertices.length; i++) {
vertices[i].index = i;
vertices[i].body = body;
}
};
Vertices.fromPath = function(path) {
var pathPattern = /L\s*([\-\d\.]*)\s*([\-\d\.]*)/ig,
vertices = [];
path.replace(pathPattern, function(match, x, y) {
vertices.push({ x: parseFloat(x, 10), y: parseFloat(y, 10) });
});
return vertices;
};
Vertices.centre = function(vertices) {
var cx = 0, cy = 0;
for (var i = 0; i < vertices.length; i++) {
cx += vertices[i].x;
cy += vertices[i].y;
}
return { x: cx / vertices.length, y: cy / vertices.length };
};
Vertices.area = function(vertices) {
var area = 0,
j = vertices.length - 1;
for (var i = 0; i < vertices.length; i++) {
area += (vertices[j].x - vertices[i].x) * (vertices[j].y + vertices[i].y);
j = i;
}
return Math.abs(area) / 2;
};
Vertices.inertia = function(vertices, mass) {
var numerator = 0,
denominator = 0,
v = vertices,
cross,
j;
// find the polygon's moment of inertia, using second moment of area
// http://www.physicsforums.com/showthread.php?t=25293
for (var n = 0; n < v.length; n++) {
j = (n + 1) % v.length;
cross = Math.abs(Vector.cross(v[j], v[n]));
numerator += cross * (Vector.dot(v[j], v[j]) + Vector.dot(v[j], v[n]) + Vector.dot(v[n], v[n]));
denominator += cross;
}
return (mass / 6) * (numerator / denominator);
};
Vertices.translate = function(vertices, vector, scalar) {
var i;
if (scalar) {
for (i = 0; i < vertices.length; i++) {
vertices[i].x += vector.x * scalar;
vertices[i].y += vector.y * scalar;
}
} else {
for (i = 0; i < vertices.length; i++) {
vertices[i].x += vector.x;
vertices[i].y += vector.y;
}
}
};
Vertices.rotate = function(vertices, angle, point) {
if (angle === 0)
return;
var cos = Math.cos(angle),
sin = Math.sin(angle);
for (var i = 0; i < vertices.length; i++) {
var vertice = vertices[i],
dx = vertice.x - point.x,
dy = vertice.y - point.y;
vertice.x = point.x + (dx * cos - dy * sin);
vertice.y = point.y + (dx * sin + dy * cos);
}
};
Vertices.contains = function(vertices, point) {
for (var i = 0; i < vertices.length; i++) {
var vertice = vertices[i],
nextVertice = vertices[(i + 1) % vertices.length];
if ((point.x - vertice.x) * (nextVertice.y - vertice.y) + (point.y - vertice.y) * (vertice.x - nextVertice.x) > 0) {
return false;
}
}
return true;
};
})();
; // End src/geometry/Vertices.js
// Begin src/render/Gui.js
var Gui = {};
(function() {
Gui.create = function(engine, options) {
var _datGuiSupported = window.dat && window.localStorage,
_serializer;
if (!_datGuiSupported) {
console.log("Could not create GUI. Check dat.gui library is loaded first.");
return;
}
var datGui = new dat.GUI(options);
if (Resurrect) {
_serializer = new Resurrect({ prefix: '$' });
_serializer.parse = _serializer.resurrect;
} else {
_serializer = JSON;
}
var gui = {
datGui: datGui,
amount: 1,
size: 40,
sides: 4,
density: 0.001,
restitution: 0,
friction: 0.1,
frictionAir: 0.01
};
var funcs = {
addBody: function() {
var options = {
density: gui.density,
friction: gui.friction,
frictionAir: gui.frictionAir,
restitution: gui.restitution
};
for (var i = 0; i < gui.amount; i++) {
World.addBody(engine.world, Bodies.polygon(120 + i * gui.size + i * 50, 200, gui.sides, gui.size, options));
}
},
clear: function() {
World.clear(engine.world, true);
Engine.clear(engine);
},
save: function() {
if (localStorage && _serializer) {
localStorage.setItem('world', _serializer.stringify(engine.world));
}
},
load: function() {
var loadedWorld;
if (localStorage && _serializer) {
loadedWorld = _serializer.parse(localStorage.getItem('world'));
}
if (loadedWorld) {
Engine.merge(engine, { world: loadedWorld });
}
}
};
var metrics = datGui.addFolder('Metrics');
metrics.add(engine.timing, 'fps').listen();
metrics.add(engine.timing, 'delta').listen();
metrics.add(engine.timing, 'correction').listen();
metrics.add(engine.metrics, 'bodies').listen();
metrics.add(engine.metrics, 'collisions').listen();
metrics.add(engine.metrics, 'pairs').listen();
metrics.add(engine.metrics, 'broadEff').listen();
metrics.add(engine.metrics, 'midEff').listen();
metrics.add(engine.metrics, 'narrowEff').listen();
metrics.close();
var controls = datGui.addFolder('Add Body');
controls.add(gui, 'amount', 1, 5).step(1);
controls.add(gui, 'size', 5, 150).step(1);
controls.add(gui, 'sides', 1, 8).step(1);
controls.add(gui, 'density', 0.0001, 0.01).step(0.001);
controls.add(gui, 'friction', 0, 1).step(0.05);
controls.add(gui, 'frictionAir', 0, gui.frictionAir * 10).step(gui.frictionAir / 10);
controls.add(gui, 'restitution', 0, 1).step(0.1);
controls.add(funcs, 'addBody');
controls.open();
var worldGui = datGui.addFolder('World');
worldGui.add(funcs, 'load');
worldGui.add(funcs, 'save');
worldGui.add(funcs, 'clear');
worldGui.open();
var gravity = worldGui.addFolder('Gravity');
gravity.add(engine.world.gravity, 'x', -1, 1).step(0.01);
gravity.add(engine.world.gravity, 'y', -1, 1).step(0.01);
gravity.open();
var physics = datGui.addFolder('Engine');
physics.add(engine, 'enableSleeping');
physics.add(engine.broadphase, 'current', ['grid', 'bruteForce']);
physics.add(engine, 'timeScale', 0.1, 2).step(0.1);
physics.add(engine, 'velocityIterations', 1, 10).step(1);
physics.add(engine, 'positionIterations', 1, 10).step(1);
physics.add(engine, 'enabled');
physics.open();
var render = datGui.addFolder('Render');
render.add(engine.render.options, 'wireframes');
render.add(engine.render.options, 'showDebug');
render.add(engine.render.options, 'showPositions');
render.add(engine.render.options, 'showBroadphase');
render.add(engine.render.options, 'showBounds');
render.add(engine.render.options, 'showVelocity');
render.add(engine.render.options, 'showCollisions');
render.add(engine.render.options, 'showAxes');
render.add(engine.render.options, 'showAngleIndicator');
render.add(engine.render.options, 'showSleeping');
render.add(engine.render.options, 'showIds');
render.add(engine.render.options, 'showShadows');
render.add(engine.render.options, 'enabled');
render.open();
//datGui.remember(world)
return gui;
};
Gui.update = function(gui, datGui) {
var i;
datGui = datGui || gui.datGui;
for (i in datGui.__folders) {
Gui.update(gui, datGui.__folders[i]);
}
for (i in datGui.__controllers) {
var controller = datGui.__controllers[i];
if (controller.updateDisplay)
controller.updateDisplay();
}
};
Gui.closeAll = function(gui) {
var datGui = gui.datGui;
for (var i in datGui.__folders) {
datGui.__folders[i].close();
}
};
})();
; // End src/render/Gui.js
// Begin src/render/Render.js
// TODO: viewports
// TODO: two.js, pixi.js
var Render = {};
(function() {
Render.create = function(options) {
var defaults = {
controller: Render,
options: {
width: 800,
height: 600,
background: '#fafafa',
wireframeBackground: '#222',
enabled: true,
wireframes: true,
showSleeping: true,
showDebug: false,
showBroadphase: false,
showBounds: false,
showVelocity: false,
showCollisions: false,
showAxes: false,
showPositions: false,
showAngleIndicator: false,
showIds: false,
showShadows: false
}
};
var render = Common.extend(defaults, options);
render.canvas = render.canvas || _createCanvas(render.options.width, render.options.height);
render.context = render.canvas.getContext('2d');
return render;
};
Render.world = function(engine) {
var render = engine.render,
world = engine.world,
canvas = render.canvas,
context = render.context,
options = render.options,
i;
if (options.wireframes) {
context.fillStyle = options.wireframeBackground;
} else {
context.fillStyle = options.background;
}
context.fillRect(0, 0, canvas.width, canvas.height);
if (options.showShadows && !options.wireframes)
for (i = 0; i < world.bodies.length; i++)
Render.bodyShadow(engine, world.bodies[i], context);
for (i = 0; i < world.bodies.length; i++)
Render.body(engine, world.bodies[i], context);
for (i = 0; i < world.constraints.length; i++)
Render.constraint(world.constraints[i], context);
if (options.showCollisions)
for (i = 0; i < engine.pairsList.length; i++)
Render.collision(engine, engine.pairsList[i], context);
if (options.showBroadphase && engine.broadphase.current === 'grid')
Render.grid(engine, engine.broadphase[engine.broadphase.current].instance, context);
if (options.showDebug)
Render.debug(engine, context);
};
Render.debug = function(engine, context) {
var c = context,
world = engine.world,
render = engine.render,
options = render.options,
space = " ";
if (engine.timing.timestamp - (render.debugTimestamp || 0) >= 500) {
var text = "";
text += "delta: " + engine.timing.delta.toFixed(3) + space;
text += "fps: " + Math.round(engine.timing.fps) + space;
text += "correction: " + engine.timing.correction.toFixed(3) + space;
text += "bodies: " + world.bodies.length + space;
if (engine.broadphase.controller === Grid)
text += "buckets: " + engine.metrics.buckets + space;
text += "\n";
text += "collisions: " + engine.metrics.collisions + space;
text += "pairs: " + engine.pairs.length + space;
text += "broad: " + engine.metrics.broadEff + space;
text += "mid: " + engine.metrics.midEff + space;
text += "narrow: " + engine.metrics.narrowEff + space;
render.debugString = text;
render.debugTimestamp = engine.timing.timestamp;
}
if (render.debugString) {
c.font = "12px Arial";
if (options.wireframes) {
c.fillStyle = 'rgba(255,255,255,0.5)';
} else {
c.fillStyle = 'rgba(0,0,0,0.5)';
}
var split = render.debugString.split('\n');
for (var i = 0; i < split.length; i++) {
c.fillText(split[i], 50, 50 + i * 18);
}
}
};
Render.constraint = function(constraint, context) {
var bodyA = constraint.bodyA,
bodyB = constraint.bodyB,
c = context;
if (!constraint.pointA || !constraint.pointB)
return;
if (bodyA) {
c.beginPath();
c.moveTo(bodyA.position.x + constraint.pointA.x, bodyA.position.y + constraint.pointA.y);
} else {
c.beginPath();
c.moveTo(constraint.pointA.x, constraint.pointA.y);
}
if (bodyB) {
c.lineTo(bodyB.position.x + constraint.pointB.x, bodyB.position.y + constraint.pointB.y);
} else {
c.lineTo(constraint.pointB.x, constraint.pointB.y);
}
c.lineWidth = constraint.lineWidth;
c.strokeStyle = constraint.strokeStyle;
c.stroke();
};
Render.bodyShadow = function(engine, body, context) {
var c = context,
render = engine.render;
if (body.circleRadius) {
c.beginPath();
c.arc(body.position.x, body.position.y, body.circleRadius, 0, 2 * Math.PI);
c.closePath();
} else {
c.beginPath();
c.moveTo(body.vertices[0].x, body.vertices[0].y);
for (var j = 1; j < body.vertices.length; j++) {
c.lineTo(body.vertices[j].x, body.vertices[j].y);
}
c.closePath();
}
var distanceX = body.position.x - render.options.width * 0.5,
distanceY = body.position.y - render.options.height * 0.2,
distance = Math.abs(distanceX) + Math.abs(distanceY);
c.shadowColor = 'rgba(0,0,0,0.15)';
c.shadowOffsetX = 0.05 * distanceX;
c.shadowOffsetY = 0.05 * distanceY;
c.shadowBlur = 1 + 12 * Math.min(1, distance / 1000);
c.fill();
c.shadowColor = null;
c.shadowOffsetX = null;
c.shadowOffsetY = null;
c.shadowBlur = null;
};
Render.body = function(engine, body, context) {
var c = context,
render = engine.render,
options = render.options;
// body bounds
if (options.showBounds) {
c.beginPath();
c.rect(body.bounds.min.x, body.bounds.min.y, body.bounds.max.x - body.bounds.min.x, body.bounds.max.y - body.bounds.min.y);
c.lineWidth = 1;
if (options.wireframes) {
c.strokeStyle = 'rgba(255,255,255,0.08)';
} else {
c.strokeStyle = 'rgba(0,0,0,0.1)';
}
c.stroke();
}
// body polygon
if (body.circleRadius) {
c.beginPath();
c.arc(body.position.x, body.position.y, body.circleRadius, 0, 2 * Math.PI);
c.closePath();
} else {
c.beginPath();
c.moveTo(body.vertices[0].x, body.vertices[0].y);
for (var j = 1; j < body.vertices.length; j++) {
c.lineTo(body.vertices[j].x, body.vertices[j].y);
}
c.closePath();
}
if (!options.wireframes) {
c.fillStyle = body.fillStyle;
if (options.showSleeping && body.isSleeping)
c.fillStyle = Common.shadeColor(body.fillStyle, 50);
c.lineWidth = body.lineWidth;
c.strokeStyle = body.strokeStyle;
c.fill();
c.stroke();
} else {
c.lineWidth = 1;
c.strokeStyle = '#bbb';
if (options.showSleeping && body.isSleeping)
c.strokeStyle = 'rgba(255,255,255,0.2)';
c.stroke();
}
// angle indicator
if (options.showAngleIndicator && !options.showAxes) {
c.beginPath();
c.moveTo(body.position.x, body.position.y);
c.lineTo((body.vertices[0].x + body.vertices[body.vertices.length-1].x) / 2,
(body.vertices[0].y + body.vertices[body.vertices.length-1].y) / 2);
c.lineWidth = 1;
if (options.wireframes) {
c.strokeStyle = 'indianred';
} else {
c.strokeStyle = body.strokeStyle;
}
c.stroke();
}
// axes
if (options.showAxes) {
for (var i = 0; i < body.axes.length; i++) {
var axis = body.axes[i];
c.beginPath();
c.moveTo(body.position.x, body.position.y);
c.lineTo(body.position.x + axis.x * 20, body.position.y + axis.y * 20);
c.lineWidth = 1;
if (options.wireframes) {
c.strokeStyle = 'indianred';
} else {
c.strokeStyle = body.strokeStyle;
}
c.stroke();
}
}
// positions
if (options.showPositions) {
c.beginPath();
c.arc(body.position.x, body.position.y, 3, 0, 2 * Math.PI, false);
if (options.wireframes) {
c.fillStyle = 'indianred';
} else {
c.fillStyle = 'rgba(0,0,0,0.5)';
}
c.fill();
c.beginPath();
c.arc(body.positionPrev.x, body.positionPrev.y, 2, 0, 2 * Math.PI, false);
c.fillStyle = 'rgba(255,165,0,0.8)';
c.fill();
}
// body velocity vector
if (options.showVelocity) {
c.beginPath();
c.moveTo(body.position.x, body.position.y);
c.lineTo(body.position.x + (body.position.x - body.positionPrev.x) * 2, body.position.y + (body.position.y - body.positionPrev.y) * 2);
c.lineWidth = 3;
c.strokeStyle = 'cornflowerblue';
c.stroke();
}
// body id
if (options.showIds) {
c.font = "12px Arial";
c.fillStyle = 'rgba(255,255,255,0.5)';
c.fillText(body.id, body.position.x + 10, body.position.y - 10);
}
};
Render.collision = function(engine, pair, context) {
var c = context,
collision = pair.collision,
options = engine.render.options;
for (var i = 0; i < pair.activeContacts.length; i++) {
var contact = pair.activeContacts[i],
vertex = contact.vertex;
c.beginPath();
//c.arc(vertex.x, vertex.y, 2.5, 0, 2 * Math.PI, false);
c.rect(vertex.x - 1.5, vertex.y - 1.5, 3.5, 3.5);
if (options.wireframes) {
c.fillStyle = 'rgba(255,255,255,0.7)';
} else {
c.fillStyle = 'orange';
}
c.fill();
}
if (pair.activeContacts.length > 0) {
var normalPosX = pair.activeContacts[0].vertex.x,
normalPosY = pair.activeContacts[0].vertex.y;
if (pair.activeContacts.length === 2) {
normalPosX = (pair.activeContacts[0].vertex.x + pair.activeContacts[1].vertex.x) / 2;
normalPosY = (pair.activeContacts[0].vertex.y + pair.activeContacts[1].vertex.y) / 2;
}
// collision normal
c.beginPath();
c.moveTo(normalPosX - collision.normal.x * 8, normalPosY - collision.normal.y * 8);
c.lineWidth = 1;
c.lineTo(normalPosX, normalPosY);
if (options.wireframes) {
c.strokeStyle = 'rgba(255,165,0,0.7)';
} else {
c.strokeStyle = 'orange';
}
c.stroke();
}
};
Render.grid = function(engine, grid, context) {
var c = context,
options = engine.render.options;
c.lineWidth = 1;
if (options.wireframes) {
c.strokeStyle = 'rgba(255,180,0,0.1)';
} else {
c.strokeStyle = 'rgba(255,180,0,0.5)';
}
var bucketKeys = Common.keys(grid.buckets);
for (var i = 0; i < bucketKeys.length; i++) {
var bucketId = bucketKeys[i];
if (grid.buckets[bucketId].length < 2)
continue;
var region = bucketId.split(',');
c.beginPath();
c.rect(0.5 + parseInt(region[0], 10) * grid.bucketWidth,
0.5 + parseInt(region[1], 10) * grid.bucketHeight,
grid.bucketWidth,
grid.bucketHeight);
c.stroke();
}
};
var _createCanvas = function(width, height) {
var canvas = document.createElement('canvas');
canvas.width = width;
canvas.height = height;
canvas.oncontextmenu = function() { return false; };
canvas.onselectstart = function() { return false; };
return canvas;
};
})();
; // End src/render/Render.js
// aliases
World.addComposite = Composite.add;
World.addBody = Composite.addBody;
World.addConstraint = Composite.addConstraint;
// exports
Matter.Body = Body;
Matter.Composite = Composite;
Matter.World = World;
Matter.Contact = Contact;
Matter.Detector = Detector;
Matter.Grid = Grid;
Matter.Manager = Manager;
Matter.Pair = Pair;
Matter.Resolver = Resolver;
Matter.SAT = SAT;
Matter.Constraint = Constraint;
Matter.MouseConstraint = MouseConstraint;
Matter.Common = Common;
Matter.Engine = Engine;
Matter.Metrics = Metrics;
Matter.Mouse = Mouse;
Matter.Sleeping = Sleeping;
Matter.Bodies = Bodies;
Matter.Composites = Composites;
Matter.Axes = Axes;
Matter.Bounds = Bounds;
Matter.Vector = Vector;
Matter.Vertices = Vertices;
Matter.Gui = Gui;
Matter.Render = Render;
// CommonJS module
if (typeof exports !== 'undefined') {
if (typeof module !== 'undefined' && module.exports) {
exports = module.exports = Matter;
}
exports.Matter = Matter;
}
// AMD module
if (typeof define === 'function' && define.amd) {
define('Matter', [], function () {
return Matter;
});
}
// browser
if (typeof window === 'object' && typeof window.document === 'object') {
window.Matter = Matter;
}
// End Matter namespace closure
})();