Brought up by @gviejo

Right now the LineGraphic and ScatterGraphic require a 2D or 3D array of xy or xyz data. This means that an extra step is required by the user to plot data that are non-continuous by creating an array with nans to fill the gaps. It should be easy to allow kwargs for xs, ys and zs for line/scatter, parse that into a pygfx buffer with nans, and that's basically it.