Gavin writes:

> Jeff writes:
>  > >Can someone think of an example where ghostscript on the 3000 would be
>  > >useful?
>  >
>  > Uh....  PCL (or other non-PostScript) printing from... say... QueryCalc?
>
>  Yeah, but for some reason I suspect Wirt would argue against doing this.

Gavin's right. The reason that we wouldn't do this is that QueryCalc already
generates high-density, quite pretty full-color PostScript output, at high
speeds (min. 600 pages/minute), at essentially zero burden to the HP3000.

A GhostScript viewer on a PC would be more appropriate to a QueryCalc user's
requirements -- and we seriously looked at that possibility several years ago.
Unfortunately, the output you generate for paper generally tends to be
inappropriate for a PC screen. 600 x 600 pixels only takes up one square inch
on a piece of paper, but consumes an entire screen on a PC. An object that
looks good on paper often simply looks terrible on a CRT due to the intrinsic
lack of resolution (a PC's screen resolution is less than a low-resolution
fax).

This effect is unfortunately true for GhostScript, Display PostScript (which
unfortunately never became a standard other than for Next computers) and early
versions of PDF (Adobe Acrobat). The newest versions of Acrobat however do a
great deal to work around the problem by algorithmically blending (blurring)
text with its background, to give much the same effect as if the image were
scanned. That actually helps a great deal.

What makes text such as you're reading now so readable is that all of the
small PC (or Mac) fonts are actually bitmaps that are hand-aligned onto the
pixel grid. A true scalable font, as occurs in PostScript, doesn't inherently
do that, thus they tend to be substantially uglier and much harder to read at
small scales.

We've given a lot of thought on how to best transfer the really pretty output
we can generate on paper onto the screen. In the past, we've given serious
consideration to not only a GhostScript-type viewer (which requires zero work
on our part because we're already compatible with GhostScript and/or Display
PostScript), but also to QueryCalc-generated HTML and PDF files.

HTML has several strikes against it. One is our inability to control a
tabulated output to the level that we would need; the second is that all
graphics would have to be generated as bitmaps, inside the HP3000. That's a
very expensive process and the avoidance of doing precisely this was the
reason we chose PostScript to begin with. Otherwise HTML is a very simple
language and we could easily generate a great deal of it at very high speeds.

PDF (portable document files) are, on the other hand, the furthest thing from
simple to generate. Nonetheless, we actually began generating a PDF
"distiller" internal to QueryCalc -- and it now works to a substantial degree.
A PDF distiller is a complicated piece of software to write, but once done, it
would be there for all future use. Moreover, Adobe Acrobat readers are free
and easily obtained, thus there would be no pain to the user associated with
such a decision.

Nevertheless, we have abandoned our work on PDF and have begun a new approach.
We are in the process of designing a third mechanism to write to a PC screen.
We're calling it "Quick & Pretty" and it will distributed for free to anyone
who wishes to use it. Now that we're giving away QCTerm at no charge, I expect
the same salutory benefits that accrued to free browsers will also accrue to
the free use of terminals.

While QueryCalc will generate native-mode Q&P code, we're purposefully keeping
the coding structure as simple as we possibly can and still allow you to write
Q&P code by hand, in Quiz, COBOL, Transact, whatever, and generate nice
looking, full-color graphical output, regardless of the programmatic source.
When we get further alone, we'll make all of this public so that you can write
your Q&P code, without requiring the use of QueryCalc.

QCTerm will have three screens: an Excel-like display that will be a client
terminal for QueryCalc (QC remains wholly HP3000-resident), which will be for
only QueryCalc users, a Reflection-like terminal emulator, which many of you
have seen, and the Q&P browser-like display. Switchover between the screens
will be automatic, based on the prefix characters that are transmitted from
the HP3000. Lines without the necessary prefixes will be handled as they
always have in the past, as standard terminal commands and output. All other
code will go to the appropriate viewer.

I don't expect Quick & Pretty to be a misnomer. All that will transmitted from
the HP3000 to the terminal will be such information as: the style of the pie
chart you desire, its size, its upper-left corner position, the colors of the
various segments, the segment labels, and the data values. That actually isn't
much text and therefore will be quite quick to transmit, much faster than PDF
and much, much faster than an equivalent page encoded in HTML. The actual
graphical rendering of these instructions will be done in QCTerm. Whether or
not the result winds up being "pretty" will depend on how good a job we do.

All of this will be free and public as soon as we get it all worked out (I
would expect by the end of the year or early next).

Wirt Atmar