A little bit with the arctangent

I decided to test out some more trig functions and put them into the equations to see what they look like on the x.y grid. I used this formula:

$arctan = atan($x/$y);
$eq=round($i*$arctan*sin($arctan))%2==0;

I then ran a series from 4.2 to 4200 increment by 10X each step. Here's what I found:

The Great Rays

Then that interference pattern from The Squares again:

Look at that detail!

It's like the birth of the cosmos:

And on into chaos...