gEDA-user: Design changs required to mill PCBs?

[DJ Delorie]

> Is HPGL at all like PCL?

HPGL is more like gerber.  It's a vector plotting language - pen up,
pen down, move here, move there, etc.

PCL is primarily a raster language.  Move cursor here, draw
text/raster/whatever.

Postscript is a combination, more of a generic programming language
that happens to have a lot of graphics-oriented primitives.  It can do
both vector and raster operations.

> I'm not very familiar with printer languages other than
> Postscript. The reason I ask is that the Epilog laser cutter to
> which I will soon have access is rumored to run on slightly tweaked
> PCL5.  Epilog does not publish specs, but some work has already been
> done to reverse engineer the protocol, and from what I gather it is
> mostly PCL5.

I'm guessing it's using a variant of HPGL embedded in a PCL data
stream.  I.e. a mode switch between languages.  The PCL5 spec has
commands for this.

You can download the PCL5 spec from HP's web site.