Custom properties in existing classes

[rudiedirkx]

Some generically named properties like speed and rotating and paused etc. don't really belong directly in existing classes IMO. I'd like a .custom property (a simple hash) that I can assign such properties to. Not in extensions of existing classes, but in their objects:

var block = new THREE.Mesh(geo, material);
block.custom.speed = 1; // instead of block.speed = 1

block.speed is not very safe, forward compatibility wise, especially with the lib being in dev.

Assigning my own .custom to the prototype won't work however, because then all objects share 1 custom hash:

THREE.Object3D.prototype.custom = {};

It's a feature request, but very simple: add this.custom = {}; to the Object3D constructor.

[mrdoob]

But... couldn't you do that on the application level? Sometimes I add my custom data to objects on my apps just like this:

var block = new THREE.Mesh(geo, material);
block.custom = { speed: 1 };

[rudiedirkx]

Yeah, that would work, but maybe on some other location you want to add another custom property and you're not sure if .custom exists. Checking it every time you read or write a custom property, that's too much =)

Without checking would be so much smoother:

block.custom.speed *= 1.1;

[chandlerprall]

I agree that the responsibility for this should be put on the application. You can extend the Mesh object and use that new object to automatically add the custom objects you want.

[rudiedirkx]

I don't want to extend the Mesh class. Another lib I use might use the Mesh class. I also don't want to override the constructor (go JS!) to add just that one line.

But I guess I don't have a choice now :)

[mrdoob]

I don't see what's the difference between extending Mesh or extending Mesh.custom.

[rudiedirkx]

Extending Mesh.custom? I don't want to extend any class (to make a new class), because Mesh might already be used somewhere else. I can override the Mesh conctructor though. That solves the whole thing (and is how I've fixed it in my THREE support lib). It's just another thing to do, that would've been easier with 1 extra line in the original Mesh constructor.

Closed?

[mrdoob]

To be honest, I don't yet understand what you wanted.
But if you think this issue is closed, then it's closed :)