registerBeforeRender runs once

[Pryme8]

What would cause a registerBeforeRender() to only fire once?  I thought this is how to set up something that fires before every frame render.

[OMAR]

registerBeforeRender() DOES fire before EVERY frame  . Can you please show us how you actually implemented this function?

[JCPalmer]

Never had a problem.  FYI, there are 2 types of BeforeRender, ones on scene & each mesh can have one. 

I actually no longer use a mesh version for morphing & skeletal interpolation.  Reason is a mesh beforerender runs for every camera that the mesh can be scene in every frame.  Running more than once per frame can cause problems for me.  This is for an extension though, so an application will probably know in advance how many cameras there are gonna be.

Since have sinned by not providing a PG, no clue on your problem.  Here is the constructor of my QI.Mesh subclass & first line of render method:

/**
 * @constructor - Args same As BABYLON.Mesh, except that using a source for cloning requires there be no shape keys
 * @param {string} name - The value used by scene.getMeshByName() to do a lookup.
 * @param {Scene} scene - The scene to add this mesh to.
 * @param {Node} parent - The parent of this mesh, if it has one
 * @param {Mesh} source - An optional Mesh from which geometry is shared, cloned.
 * @param {boolean} doNotCloneChildren - When cloning, skip cloning child meshes of source, default False.
 *                  When false, achieved by calling a clone(), also passing False.
 *                  This will make creation of children, recursive.
 */
constructor(name: string, scene: BABYLON.Scene, parent: BABYLON.Node = null, source?: Mesh, doNotCloneChildren?: boolean) {
    super(name, scene, parent, source, doNotCloneChildren);
    if (source && source._shapeKeyGroups.length > 0) throw "QI.Mesh: meshes with shapekeys cannot be cloned";
    this._engine = scene.getEngine(); 
            
    this._povProcessor = new PovProcessor(this, false);  // do not actually register as a beforeRender, use this classes & register below
            
    // tricky registering a prototype as a callback in constructor; cannot say 'this.beforeRender()' & must be wrappered
    var ref = this;
    // using scene level before render, so always runs & only once per frame, incase there are multiple cameras
    scene.registerBeforeRender(function(){ref.beforeRender();});
}
// ============================ beforeRender callback & tracking =============================
public beforeRender() : void {
    . . .
}

 

[Pryme8]

http://www.babylonjs-playground.com/#22OE8Q#12

A lot of comments are missing because this is just a temporary playground, the real one I am keeping clean and making sure my incremental values of the pg are set so the person following my tutorial can just go to the next one.  so if some of this seems like it its extra ignore it.

The line where the register is 122

[RaananW]

You need to input a function, not a function call. Try without the () . 

What you do is call this function and register the value returned from it. So it's only called once

[Pryme8]

Thank you Raan this worked

[Pryme8]

how do I pass arguments with it then?

[RaananW]

Well, this is a javascript question

function loop(arg) {
    return function() {
        console.log(arg);
    }
}

scene.registerBeforeRender(loop("foo"));

You could also use the bind method.

[Pryme8]

thats brilliant.

wow man wow.