phaser/todo/physics/ContactSolver.js
2013-08-02 12:38:56 +01:00

269 lines
16 KiB
JavaScript

var Phaser;
(function (Phaser) {
/// <reference path="../math/Vec2.ts" />
/// <reference path="../geom/Point.ts" />
/// <reference path="../math/Vec2Utils.ts" />
/// <reference path="AdvancedPhysics.ts" />
/// <reference path="Body.ts" />
/// <reference path="shapes/Shape.ts" />
/// <reference path="Contact.ts" />
/**
* Phaser - Advanced Physics - ContactSolver
*
* Based on the work Ju Hyung Lee started in JS PhyRus.
*/
//-------------------------------------------------------------------------------------------------
// Contact Constraint
//
// Non-penetration constraint:
// C = dot(p2 - p1, n)
// Cdot = dot(v2 - v1, n)
// J = [ -n, -cross(r1, n), n, cross(r2, n) ]
//
// impulse = JT * lambda = [ -n * lambda, -cross(r1, n) * lambda, n * lambda, cross(r1, n) * lambda ]
//
// Friction constraint:
// C = dot(p2 - p1, t)
// Cdot = dot(v2 - v1, t)
// J = [ -t, -cross(r1, t), t, cross(r2, t) ]
//
// impulse = JT * lambda = [ -t * lambda, -cross(r1, t) * lambda, t * lambda, cross(r1, t) * lambda ]
//
// NOTE: lambda is an impulse in constraint space.
//-------------------------------------------------------------------------------------------------
(function (Physics) {
var ContactSolver = (function () {
function ContactSolver(shape1, shape2) {
this.shape1 = shape1;
this.shape2 = shape2;
this.contacts = [];
this.elasticity = 1;
this.friction = 1;
}
ContactSolver.prototype.update = function (newContactArr) {
for(var i = 0; i < newContactArr.length; i++) {
var newContact = newContactArr[i];
var k = -1;
for(var j = 0; j < this.contacts.length; j++) {
if(newContact.hash == this.contacts[j].hash) {
k = j;
break;
}
}
if(k > -1) {
newContact.lambdaNormal = this.contacts[k].lambdaNormal;
newContact.lambdaTangential = this.contacts[k].lambdaTangential;
}
}
this.contacts = newContactArr;
};
ContactSolver.prototype.initSolver = function (dt_inv) {
var body1 = this.shape1.body;
var body2 = this.shape2.body;
var sum_m_inv = body1.massInverted + body2.massInverted;
for(var i = 0; i < this.contacts.length; i++) {
var con = this.contacts[i];
//console.log('initSolver con');
//console.log(con);
// Transformed r1, r2
Phaser.Vec2Utils.subtract(con.point, body1.position, con.r1);
Phaser.Vec2Utils.subtract(con.point, body2.position, con.r2);
//con.r1 = vec2.sub(con.point, body1.p);
//con.r2 = vec2.sub(con.point, body2.p);
// Local r1, r2
Phaser.TransformUtils.unrotate(body1.transform, con.r1, con.r1_local);
Phaser.TransformUtils.unrotate(body2.transform, con.r2, con.r2_local);
//con.r1_local = body1.transform.unrotate(con.r1);
//con.r2_local = body2.transform.unrotate(con.r2);
var n = con.normal;
var t = Phaser.Vec2Utils.perp(con.normal);
// invEMn = J * invM * JT
// J = [ -n, -cross(r1, n), n, cross(r2, n) ]
var sn1 = Phaser.Vec2Utils.cross(con.r1, n);
var sn2 = Phaser.Vec2Utils.cross(con.r2, n);
var emn_inv = sum_m_inv + body1.inertiaInverted * sn1 * sn1 + body2.inertiaInverted * sn2 * sn2;
con.emn = emn_inv == 0 ? 0 : 1 / emn_inv;
// invEMt = J * invM * JT
// J = [ -t, -cross(r1, t), t, cross(r2, t) ]
var st1 = Phaser.Vec2Utils.cross(con.r1, t);
var st2 = Phaser.Vec2Utils.cross(con.r2, t);
var emt_inv = sum_m_inv + body1.inertiaInverted * st1 * st1 + body2.inertiaInverted * st2 * st2;
con.emt = emt_inv == 0 ? 0 : 1 / emt_inv;
// Linear velocities at contact point
// in 2D: cross(w, r) = perp(r) * w
var v1 = new Phaser.Vec2();
var v2 = new Phaser.Vec2();
Phaser.Vec2Utils.multiplyAdd(body1.velocity, Phaser.Vec2Utils.perp(con.r1), body1.angularVelocity, v1);
Phaser.Vec2Utils.multiplyAdd(body2.velocity, Phaser.Vec2Utils.perp(con.r2), body2.angularVelocity, v2);
//var v1 = vec2.mad(body1.v, vec2.perp(con.r1), body1.w);
//var v2 = vec2.mad(body2.v, vec2.perp(con.r2), body2.w);
// relative velocity at contact point
var rv = new Phaser.Vec2();
Phaser.Vec2Utils.subtract(v2, v1, rv);
//var rv = vec2.sub(v2, v1);
// bounce velocity dot n
con.bounce = Phaser.Vec2Utils.dot(rv, con.normal) * this.elasticity;
}
};
ContactSolver.prototype.warmStart = function () {
var body1 = this.shape1.body;
var body2 = this.shape2.body;
for(var i = 0; i < this.contacts.length; i++) {
var con = this.contacts[i];
var n = con.normal;
var lambda_n = con.lambdaNormal;
var lambda_t = con.lambdaTangential;
// Apply accumulated impulses
//var impulse = vec2.rotate_vec(new vec2(lambda_n, lambda_t), n);
//var impulse = new vec2(lambda_n * n.x - lambda_t * n.y, lambda_t * n.x + lambda_n * n.y);
var impulse = new Phaser.Vec2(lambda_n * n.x - lambda_t * n.y, lambda_t * n.x + lambda_n * n.y);
//console.log('phaser warmStart impulse ' + i + ' = ' + impulse.toString());
body1.velocity.multiplyAddByScalar(impulse, -body1.massInverted);
//body1.v.mad(impulse, -body1.m_inv);
body1.angularVelocity -= Phaser.Vec2Utils.cross(con.r1, impulse) * body1.inertiaInverted;
//body1.w -= vec2.cross(con.r1, impulse) * body1.i_inv;
body2.velocity.multiplyAddByScalar(impulse, body2.massInverted);
//body2.v.mad(impulse, body2.m_inv);
body2.angularVelocity += Phaser.Vec2Utils.cross(con.r2, impulse) * body2.inertiaInverted;
//body2.w += vec2.cross(con.r2, impulse) * body2.i_inv;
}
};
ContactSolver.prototype.solveVelocityConstraints = function () {
var body1 = this.shape1.body;
var body2 = this.shape2.body;
Physics.AdvancedPhysics.write('solveVelocityConstraints. Body1: ' + body1.name + ' Body2: ' + body2.name);
Physics.AdvancedPhysics.write('Shape 1: ' + this.shape1.type + ' Shape 2: ' + this.shape2.type);
var m1_inv = body1.massInverted;
var i1_inv = body1.inertiaInverted;
var m2_inv = body2.massInverted;
var i2_inv = body2.inertiaInverted;
Physics.AdvancedPhysics.write('m1_inv: ' + m1_inv);
Physics.AdvancedPhysics.write('i1_inv: ' + i1_inv);
Physics.AdvancedPhysics.write('m2_inv: ' + m2_inv);
Physics.AdvancedPhysics.write('i2_inv: ' + i2_inv);
for(var i = 0; i < this.contacts.length; i++) {
Physics.AdvancedPhysics.write('------------ solve con ' + i);
var con = this.contacts[i];
var n = con.normal;
var t = Phaser.Vec2Utils.perp(n);
var r1 = con.r1;
var r2 = con.r2;
// Linear velocities at contact point
// in 2D: cross(w, r) = perp(r) * w
var v1 = new Phaser.Vec2();
var v2 = new Phaser.Vec2();
Phaser.Vec2Utils.multiplyAdd(body1.velocity, Phaser.Vec2Utils.perp(r1), body1.angularVelocity, v1);
//var v1 = vec2.mad(body1.v, vec2.perp(r1), body1.w);
Physics.AdvancedPhysics.write('v1 ' + v1.toString());
Phaser.Vec2Utils.multiplyAdd(body2.velocity, Phaser.Vec2Utils.perp(r2), body2.angularVelocity, v2);
//var v2 = vec2.mad(body2.v, vec2.perp(r2), body2.w);
Physics.AdvancedPhysics.write('v2 ' + v2.toString());
// Relative velocity at contact point
var rv = new Phaser.Vec2();
Phaser.Vec2Utils.subtract(v2, v1, rv);
//var rv = vec2.sub(v2, v1);
Physics.AdvancedPhysics.write('rv ' + rv.toString());
// Compute normal constraint impulse + adding bounce as a velocity bias
// lambda_n = -EMn * J * V
var lambda_n = -con.emn * (Phaser.Vec2Utils.dot(n, rv) + con.bounce);
Physics.AdvancedPhysics.write('lambda_n: ' + lambda_n);
// Accumulate and clamp
var lambda_n_old = con.lambdaNormal;
con.lambdaNormal = Math.max(lambda_n_old + lambda_n, 0);
//con.lambdaNormal = this.clamp(lambda_n_old + lambda_n, 0);
lambda_n = con.lambdaNormal - lambda_n_old;
Physics.AdvancedPhysics.write('lambda_n clamped: ' + lambda_n);
// Compute frictional constraint impulse
// lambda_t = -EMt * J * V
var lambda_t = -con.emt * Phaser.Vec2Utils.dot(t, rv);
// Max friction constraint impulse (Coulomb's Law)
var lambda_t_max = con.lambdaNormal * this.friction;
// Accumulate and clamp
var lambda_t_old = con.lambdaTangential;
con.lambdaTangential = this.clamp(lambda_t_old + lambda_t, -lambda_t_max, lambda_t_max);
lambda_t = con.lambdaTangential - lambda_t_old;
// Apply the final impulses
//var impulse = vec2.rotate_vec(new vec2(lambda_n, lambda_t), n);
var impulse = new Phaser.Vec2(lambda_n * n.x - lambda_t * n.y, lambda_t * n.x + lambda_n * n.y);
Physics.AdvancedPhysics.write('impulse: ' + impulse.toString());
body1.velocity.multiplyAddByScalar(impulse, -m1_inv);
//body1.v.mad(impulse, -m1_inv);
body1.angularVelocity -= Phaser.Vec2Utils.cross(r1, impulse) * i1_inv;
//body1.w -= vec2.cross(r1, impulse) * i1_inv;
body2.velocity.multiplyAddByScalar(impulse, m2_inv);
//body2.v.mad(impulse, m2_inv);
body2.angularVelocity += Phaser.Vec2Utils.cross(r2, impulse) * i2_inv;
//body2.w += vec2.cross(r2, impulse) * i2_inv;
Physics.AdvancedPhysics.write('body1: ' + body1.toString());
Physics.AdvancedPhysics.write('body2: ' + body2.toString());
}
};
ContactSolver.prototype.solvePositionConstraints = function () {
var body1 = this.shape1.body;
var body2 = this.shape2.body;
Physics.AdvancedPhysics.write('solvePositionConstraints');
var m1_inv = body1.massInverted;
var i1_inv = body1.inertiaInverted;
var m2_inv = body2.massInverted;
var i2_inv = body2.inertiaInverted;
var sum_m_inv = m1_inv + m2_inv;
var max_penetration = 0;
for(var i = 0; i < this.contacts.length; i++) {
Physics.AdvancedPhysics.write('------------- solvePositionConstraints ' + i);
var con = this.contacts[i];
var n = con.normal;
var r1 = new Phaser.Vec2();
var r2 = new Phaser.Vec2();
// Transformed r1, r2
Phaser.Vec2Utils.rotate(con.r1_local, body1.angle, r1);
Phaser.Vec2Utils.rotate(con.r2_local, body2.angle, r2);
Physics.AdvancedPhysics.write('r1_local.x = ' + con.r1_local.x + ' r1_local.y = ' + con.r1_local.y + ' angle: ' + body1.angle);
Physics.AdvancedPhysics.write('r1 rotated: r1.x = ' + r1.x + ' r1.y = ' + r1.y);
Physics.AdvancedPhysics.write('r2_local.x = ' + con.r2_local.x + ' r2_local.y = ' + con.r2_local.y + ' angle: ' + body2.angle);
Physics.AdvancedPhysics.write('r2 rotated: r2.x = ' + r2.x + ' r2.y = ' + r2.y);
// Contact points (corrected)
var p1 = new Phaser.Vec2();
var p2 = new Phaser.Vec2();
Phaser.Vec2Utils.add(body1.position, r1, p1);
Phaser.Vec2Utils.add(body2.position, r2, p2);
Physics.AdvancedPhysics.write('body1.pos.x=' + body1.position.x + ' y=' + body1.position.y);
Physics.AdvancedPhysics.write('body2.pos.x=' + body2.position.x + ' y=' + body2.position.y);
// Corrected delta vector
var dp = new Phaser.Vec2();
Phaser.Vec2Utils.subtract(p2, p1, dp);
// Position constraint
var c = Phaser.Vec2Utils.dot(dp, n) + con.depth;
var correction = this.clamp(Physics.AdvancedPhysics.CONTACT_SOLVER_BAUMGARTE * (c + Physics.AdvancedPhysics.CONTACT_SOLVER_COLLISION_SLOP), -Physics.AdvancedPhysics.CONTACT_SOLVER_MAX_LINEAR_CORRECTION, 0);
if(correction == 0) {
continue;
}
// We don't need max_penetration less than or equal slop
max_penetration = Math.max(max_penetration, -c);
// Compute lambda for position constraint
// Solve (J * invM * JT) * lambda = -C / dt
var sn1 = Phaser.Vec2Utils.cross(r1, n);
var sn2 = Phaser.Vec2Utils.cross(r2, n);
var em_inv = sum_m_inv + body1.inertiaInverted * sn1 * sn1 + body2.inertiaInverted * sn2 * sn2;
var lambda_dt = em_inv == 0 ? 0 : -correction / em_inv;
// Apply correction impulses
var impulse_dt = new Phaser.Vec2();
Phaser.Vec2Utils.scale(n, lambda_dt, impulse_dt);
body1.position.multiplyAddByScalar(impulse_dt, -m1_inv);
body1.angle -= sn1 * lambda_dt * i1_inv;
body2.position.multiplyAddByScalar(impulse_dt, m2_inv);
body2.angle += sn2 * lambda_dt * i2_inv;
Physics.AdvancedPhysics.write('body1.pos.x=' + body1.position.x + ' y=' + body1.position.y);
Physics.AdvancedPhysics.write('body2.pos.x=' + body2.position.x + ' y=' + body2.position.y);
}
Physics.AdvancedPhysics.write('max_penetration: ' + max_penetration);
return max_penetration <= Physics.AdvancedPhysics.CONTACT_SOLVER_COLLISION_SLOP * 3;
};
ContactSolver.prototype.clamp = function (v, min, max) {
return v < min ? min : (v > max ? max : v);
};
return ContactSolver;
})();
Physics.ContactSolver = ContactSolver;
})(Phaser.Physics || (Phaser.Physics = {}));
var Physics = Phaser.Physics;
})(Phaser || (Phaser = {}));