subtractToRef is not a function in Event Handler

Questions
1

Registering my event:

window.addEventListener('isClosed', reDrawFloorplan);

Once I trigger it:

setTimeout(
    () => window.dispatchEvent(new Event('isClosed')
), 500);

I get:
Capture
my code at line 17:

corners[1].subtractToRef(corners[0], line);

Line 17 is the first line that uses Babylon.js code.

Why is this happening? Should I be using an Observable instead or its not related?

2

This is impossible to tell without a repro. It might be and is more likely just a typo. We need to see how and when the array is initialized filled in and so on.

Could you repro in a playground ?

3

I was saving whole meshes in my array, not the positions.

It works here https://www.babylonjs-playground.com/#80179F#3.

Fixed it but now I get a different error:
Capture

My array looks fine though.
Capture

Any idea what it could be?

4

This means the output of subtractToRef is undefined in some cases e.g. at some point in your code line is undefined.

5

Found the problem. I didnt assign BABYLON.Vector3.Zero() in the begin.

    let line; // = BABYLON.Vector3.Zero();

    cornersPos[1].subtractToRef(cornersPos[0], line);

Why do I have to assign Vector Zero first?

6

API both parameters have to be vectors Vector3 - Babylon.js Documentation

Does not have to be a zero vector but is a simple way of making sure it is a Vector3

1 Like
7

This prevents GC snd ensures you can reuse at max from frame to frame.

1 Like