[GUI] Lines array is generated later

[RaananW]

this._lines is generated when the control is in view. If you create a control that is not in view it will fail.

This makes sure it doesn't fail even when out of view.

Test playground - https://www.babylonjs-playground.com/#XCPP9Y#13890

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[sebavan]

overall It sounds weird we are going in render if we do not have the required infos ???

[RaananW]

overall It sounds weird we are going in render if we do not have the required infos ???

That is the GUI render loop. and I agree. Those objects are only initialized on the first actual render, but the function is running on every render call, even if outside of the frustum.

This requires a slight overhaul of the GUI render loop.