🚀 go-pugleaf

Misha Rekhson writes
  
  My questions: what exactly is Display PostScript? Is it a program? A concept?
  How does it fit with DECwindows? Where is it available?

Display PostScript is a software program/library from Adobe. A program can  
issue 'wrapped' postscript to it (close to identical to a postscript file) and  
make subroutine calls (to draw piece by piece). Postscript fonts get rasterized  
and handled on the screen.

I asked my original question (which you responded to) because I am pleased with  
DPS on the NeXT and wonder if this will grow in use. The approach seems quite  
sound ... to me.

DEC advertises that it is available for DECwindows.
  
  What is "run-time graphics support"?

Versus writing a file that is later interpreted for display/printing, generate  
graphics in an interactive mode from a running program. That is, a lineto  
should draw on the screen right then.
  
  I have a Decstation5000 and have dxpsview (Dec's PostScript previewer), but
  I haven't heard of "run-time" system for Decwindows.

I cannot claim to be intimate with this. I did confirm that DEC offers it and  
there were several folk here who responded that they use it and it works well  
(if a bit less smooth than NeXT).
  
  Please excuse me if the questions sound naive...

Please excuse me if I have not helped.