[1.12] Static and Dynamic Blockmodel?

[EvilTwin]

So the Beacon in Minecraft has a Static Blockmodel (the Beacon) and a dynamic model (the beam), the beam only activates when isComplete equals true, but how does it do this, I've been trying to reproduce this for a while now, and I don't see how I should be able to render the beam, after I rendered the "beacon" itself, I have tried to reproduce  everything in the Block, the TileEntity and the TileEntityRenderer classes, to an extent that it should work. But I can't seem to find the actual event that calls for the rendering of the beam, looking in the ContainerBeacon and GuiBeacon classes didn't help either. 

My problem that I have is that I can't find the line that tells the TileEntityRenderer to actually render the beam. I have two instances in which I can have my own TileEntity update it's model/render the beam, but I don't know how to implement it I mean I can't just add in 

render(TileEntityModEntity te, double x, double y, double z, float partialTicks, int destroyStage, float alpha)

and thats it I have to update the TileEntity somehow right?

When is this render called by the Beacon, when it should render the Beam?

Edited December 25, 2017 by EvilTwin