preStepPlayerZep: function(body) {
if (body.thing.state.up && body.thing.go) {
body.ApplyForce(ccp(0, 25), body.GetPosition());
} else {
body.ApplyForce(ccp(0, -15), body.GetPosition());
}
if (body.thing.state.nitro) {
body.ApplyForce(ccp(30, 0), body.GetPosition());
}
var time = Date.now(),
v = body.GetLinearVelocity();
if (this.groups.puffs && time - this.lastCloudCheck > this.cloudCheckPeriod) {
this.lastCloudCheck = time;
var impact = 1000;
for (var ii in this.groups.puffs) {
var puff = this.groups.puffs[ii],
sqD = geo.ccpLengthSQ(geo.ccpSub(body.thing.location, puff.location));
// distance between centers is less than 4
if (sqD < 25) {
var shape1 = new box2d.b2CircleShape(puff.radius * puff.scale),
t1 = new box2d.b2Transform,
t2 = new box2d.b2Transform;
t1.position.Set(puff.location.x, puff.location.y);
t2.position.Set(body.thing.location.x, body.thing.location.y);
if (box2d.b2Shape.TestOverlap(shape1, t1, body.GetFixtureList().GetShape(), t2)) {
if (puff.dissolveTime) {
puff.friction = 1 - puff.age / puff.dissolveTime + 0.01;
}
var candidImpact = 0.05 / puff.friction / puff.friction * sqD;
if (candidImpact < impact) impact = candidImpact;
}
}
}
if (impact < 1000) {
if (Math.abs(v.x) > impact + this.puffFactor) v.x = impact * geo.sign(v.x);
if (Math.abs(v.y) > impact + this.puffFactor) v.y = impact * geo.sign(v.y);
}
}
body.thing.velocity = Math.floor(v.x * 10) / 10;
},
preStepZep: function(body) {
var speedY = body.GetLinearVelocity().y,
targetAngle = speedY > 0? 0.15 : -0.15,
rotation = geo.closestRotation(body.thing.angle, targetAngle);
if (Math.abs(rotation) > 0.05) {
body.ApplyTorque(geo.sign(rotation)/3 + rotation * 2);
}
// compensate gravity
body.ApplyForce(geo.ccpMult(this.world.GetGravity(), ccp(0, -body.GetMass())), body.thing.location);
// engine pushes at full speed for 0 angle. To make effect stronger we use cos^2
var cos = Math.cos(body.thing.angle),
speed = this.thrust * Math.max(0, cos * cos);
body.ApplyForce(geo.ccpMult(ccp(speed, 0), body.thing.direction), body.thing.location);
// "roof" presses on all zeppelins, seed>-2 limits feedback
var y = body.thing.location.y;
if (y > this.roof && speedY > -2) {
body.ApplyForce(ccp(0, -this.roof * (y-this.roof) * (y-this.roof)), body.thing.location);
};
},