* Diameter of the dots as a fraction of the width of the display's width in pixels -- for example, for a 1024-pixel display, a width of 0.01 gives a dot diameter of 10 pixels.  The particle engine multiplies this raw width by sqrt(1/d) where d is the distance from a virtual camera in arbitrary camera units.  d is always almost exactly 5 units, and therefore sqrt(1/d) is always almost exactly 0.4472, making the final width in this example 5 pixels (rounded up from 4.5795).  NOTE: ESPECIALLY WITH THIS WEIRD 0.4472 FACTOR WHICH EXPERIMENTERS WILL ALWAYS HAVE TO INVERT WHEN CALCULATING THEIR DESIRED PARAMETERS, IT SEEMS A LOT EASIER TO BE ABLE TO SPECIFY DOT DIAMETERS IN RADIANS.  CAN WE JUST DO THAT?
 
* Diameter of the dots as a fraction of the width of the display's width in pixels -- for example, for a 1024-pixel display, a width of 0.01 gives a dot diameter of 10 pixels.  The particle engine multiplies this raw width by sqrt(1/d) where d is the distance from a virtual camera in arbitrary camera units.  d is always almost exactly 5 units, and therefore sqrt(1/d) is always almost exactly 0.4472, making the final width in this example 5 pixels (rounded up from 4.5795).  NOTE: ESPECIALLY WITH THIS WEIRD 0.4472 FACTOR WHICH EXPERIMENTERS WILL ALWAYS HAVE TO INVERT WHEN CALCULATING THEIR DESIRED PARAMETERS, IT SEEMS A LOT EASIER TO BE ABLE TO SPECIFY DOT DIAMETERS IN RADIANS.  CAN WE JUST DO THAT?