GraphNode class and all methods create a lot of garbage

Help & Support
1

Hi play canvas team, i have a project where have a lot of simple entities(200 and more), they moving, rotating. And i notice sometimes they all freeze when run GC, for my game this is not acceptable, can you reduce places where you engine generate new objects in memory and i think GraphNode is good place for that. This code sample from you repository:

setPosition: function ()
{
// posible move to GraphNode temp variables, create once on class init,
var position = new pc.Vec3();
// posible move to GraphNode temp variables, create once on class init,
var invParentWtm = new pc.Mat4()

        // generate new function(produce garbage), i think this is bad too
        return function (x, y, z) {
            if (x instanceof pc.Vec3) {
                position.copy(x);
            } else {
                position.set(x, y, z);
            }

            if (this._parent === null) {
                this.localPosition.copy(position);
            } else {
                invParentWtm.copy(this._parent.getWorldTransform()).invert();
                invParentWtm.transformPoint(position, this.localPosition);
            }

            if (!this._dirtyLocal)
                this._dirtify(true);
        };

}

Also i see when i enable or disable rigidbody, it also generate garbage in memory, so it is not posible using Pool pattern for rigidbody, when i disable or enable entire Entity.

2

The setPosition function doesn’t generate any new objects (from the code you have posted). Can you create an example where the GC is called just by moving/rotating a lot of entities please?

3

var position = new pc.Vec3() and var invParentWtm = new pc.Mat4(); оn setPosition start

setPosition: function () {
var position = new pc.Vec3(); // posible move to GraphNode temp variables, create once on class init,
var invParentWtm = new pc.Mat4(); // posible move to GraphNode temp variables, create once on class init,

4

The setPosition function is using a closure so position and invParentWtm are only created once during the app lifetime, not every time the function is called.

1 Like
5

Thanks, you right! Just started learn JavaScript, and get used to new ‘language feature’.