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Support for various monitor pixel densities??

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Francis Favorini

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Dec 7, 1990, 9:23:17 PM12/7/90
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I've been wondering for a while whether or not the is any current provision
(or future one) in Mac system software for monitors with pixel densities
other than 72 dots per inch. I.e. if I get a monitor (e.g. Sony 1304 13")
which supports 1024 X 768 in addition to 640 X 480, can I use the hi-res mode.
And if so, will all my windows/graphics be shrunken proportionally to the
increase in resolution (pixel density). As fas as I know, there is no
provision for such varied densities. There are monitors (including the new
12" jobs from Apple) with slightly worse or better resolutions (~64-80? dpi),
but I am assuming no attempt is made to rescale fonts and such by system
or add-on software. Is this true?

Anyhow, the point is, it seems like an important and not terribly complicated
problem to be solved. We don't want to be stuck with 72 dpi forever. Even
the NeXT's have 90 dpi monitors.;-) Anyone at Apple or a hacker who has some
real info on this care to clue me in?

Just curious.
--
______________________________________________________________________________
Francis Favorini favo...@cs.yale.edu
favo...@yalecs.bitnet
...!yale!favorini

Evan James Torrie

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Dec 8, 1990, 1:36:11 AM12/8/90
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favorini...@CS.YALE.EDU (Francis Favorini) writes:

>Anyhow, the point is, it seems like an important and not terribly complicated
>problem to be solved. We don't want to be stuck with 72 dpi forever. Even
>the NeXT's have 90 dpi monitors.;-) Anyone at Apple or a hacker who has some
>real info on this care to clue me in?

Well, we all have to wait for the resolution-independent version of
QuickDraw to come out. According to one of the keynote speakers at a
recent MacExpo, the codename for this project is "Pink", and it's
certainly alive and well inside Apple...


--
------------------------------------------------------------------------------
Evan Torrie. Stanford University, Class of 199? tor...@cs.stanford.edu
"I didn't get where I am today without knowing a good deal when I see one,
Reggie." "Yes, C.J."

Robert Minich

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Dec 8, 1990, 7:18:02 AM12/8/90
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by favorini...@CS.YALE.EDU (Francis Favorini):

> I've been wondering for a while whether or not the is any current provision
> (or future one) in Mac system software for monitors with pixel densities
> other than 72 dots per inch.

Currently: all dots are 72dpi dots.
Future: who knows?

> ... I am assuming no attempt is made to rescale fonts and such by system


> or add-on software. Is this true?

Yes. I believe it is possible to query a video driver to find the real
resolution of the screen and I suppose a program could attempt to scale
from that, but I don't know of any that do.

> Anyhow, the point is, it seems like an important and not terribly complicated
> problem to be solved. We don't want to be stuck with 72 dpi forever. Even
> the NeXT's have 90 dpi monitors.;-) Anyone at Apple or a hacker who has some
> real info on this care to clue me in?
>
> Just curious.

Unfortunately, 72dpi (and even 100dpi) is not that high of resolution.
There are serious problems with scalable graphics (outline fonts, for
example) that are headed for low resolution devices. The quality is just
not that great. (Stay with me, this _is_ going somewhere!) So what has
been done? Hand-tuned fonts are one approach. Hinted fonts are another.
The real uglies come with the more finely tuned graphics: icons,
controls, etc. These would probably not scale very well to 100dpi or
90dpi or whatever unless whatever == a simple multiple of 72.
I am curious as to what the NeXT does with that unified imaging model.
<big smiley> Other uglies might be title bars, sicn's, label text in the
Finder, etc. Icons might be somewhat doable on multi-bit depth monitors
by some sort of blurring/anti-aliasing. However, I _like_ the sharp
images that typify Mac displays.
Ideally, Apple would first support very high res monitors (~150dpi) by
scaling one standard pixel to four hires pixels. That should make all
the old things work just fine (assuming they don't do their own bliting)
while allowing new apps to have some really nice looking graphics. Of
course, fonts would look MUCH sharper in all apps. All this capability
would (will?) require a lot of effort to specify and code. At this
point, I can't even decide what would be the "correct" output for a
non-72dpi-multiple monitor, much less suggest something to impose on the
world. Hopefully, we'll all be pleasantly surprised by System 8 with all
the things we've been crying for (preempive multitasking, protected
memory, new memory mgmt model [this one is mine], new print
architecture, support for permissions on non-AppleShare volumes, etc.)
but somehow I'm just not that optimistic. :-(
--
|_ /| | Robert Minich |
|\'o.O' | Oklahoma State University| "I'm a newcomer here, but does the
|=(___)= | min...@d.cs.okstate.edu | net every lay any argument to rest?"
| U | - Ackphtth | -- dan herrick

da...@svc.portal.com

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Dec 9, 1990, 4:24:36 PM12/9/90
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In article <27...@cs.yale.edu> favorini...@CS.YALE.EDU (Francis Favorini) writes:
>I've been wondering for a while whether or not the is any current provision
>(or future one) in Mac system software for monitors with pixel densities
>other than 72 dots per inch.
>
>As fas as I know, there is no provision for such varied densities. There
>are monitors (including the new 12" jobs from Apple) with slightly worse or
>better resolutions (~64-80? dpi), but I am assuming no attempt is made to
>rescale fonts and such by system or add-on software. Is this true?
>
>Anyhow, the point is, it seems like an important and not terribly complicated
>problem to be solved. We don't want to be stuck with 72 dpi forever. Even
>the NeXT's have 90 dpi monitors.;-) Anyone at Apple or a hacker who has some
>real info on this care to clue me in?

Francis,

I haven't heard any rumors of resolution independancy sneaking out of Apple
in awhile. However, TrueType being based on mathematical curves and not bitmaps
should itself be resolution independant. Whether Apple will take advantage of
this fact remains to be seen.

From a programmer's standpoint, it seems to me that with QuickDraw being based
on the pixel plane, descisions on drawing text and line would be invalidated
if the MacOS started scaling fonts behind the applications's back.
Applications are likely to produce some wild looking text displays should the
MacOS start drawing the text in ways that consume more, or less, pixels than
the application thought it would.


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Berkeley, CA (415) 644-3232 | AOL: MicroPhone | CIS: 76004,2161
-------------------------------------------------------------------------------

Francis Favorini

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Dec 10, 1990, 10:39:06 PM12/10/90
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In article <1990Dec9.2...@svc.portal.com> da...@svc.portal.com writes:
>From a programmer's standpoint, it seems to me that with QuickDraw being based
>on the pixel plane, descisions on drawing text and line would be invalidated
>if the MacOS started scaling fonts behind the applications's back.
>Applications are likely to produce some wild looking text displays should the
>MacOS start drawing the text in ways that consume more, or less, pixels than
>the application thought it would.

OK. Several people have pointed this out. It seems to me that the
benefits of a resolution (i.e. pixel density) independent drawing
metaphor are great indeed. When the folks at Radius, SuperMac,
RasterOps, et al come out with cheap 100, 200 and even 300 dpi screens
(ok so they might not be cheap), do you want to be looking at your
pathetic 72 dpi screen. We're talking *real* WYSIWYG, especially with
anti-aliasing, "true-color", etc.
What we need is to bag the pixel-based QuickDraw system. Pixels are
a bad unit to measure with since they come in different sizes. We
should use real units of linear measurement: points, picas, inches,
centimeters, furlongs, who cares! The point is to use something that
won't change from screen to screen. Leave it up to the system
software to map these units to pixels on screen. What's the downside?
Old apps will look UGLY, you say. OK. Make the old system's "pixels"
turn into 1/72" by 1/72" squares in the new system. Thus, a 72 pixel
line drawn by MacDraw 1.0 using QuickDraw will be an inch on anyone's
screen using our new drawing system, SlickDraw. Yes, we must be
reverse-compatible to our previous mistakes.
I can already hear people groaning about how ugly icons (16 x 16, 32
x 32 pixels, etc.) will look mapped to 90 dpi. Fair enough. Two half
answers: 1) Could be improved by anti-aliasing techniques. I've heard of
a $20 chip (made by a company whose name I forget) that does this at
the bitmap level on VGA boards (yes, IBM stuff). The chip is totally
transparent to the software and even the hardware. It replaces a
standard chip found on almost all VGA video boards. It performs that
chip's functions, in addition to its own. Pretty sneaky. And only
$20 bucks for ~50% better perceived resolution. (This is all off
the top of my head, so please excuse inaccuracies and holes. This is
from an article in PC Week, I think.)
2) Hardware vendors could limit their resolutions to multiples
of 72 (or maybe 36 or 18, say). This would minimalize the UGLIES.
Note also, that this would probably be unnecessary at resolutions >200
dpi, due to all those dots. Any hardware types care to comment on
cutting-edge technology re: hi-res monitors and their ETA's? Five
years 'til I get my 216 dpi Apple Hi^3Res monitor? Ten? I can't
wait. Of course, it won't emit any harmful radiation, it'll be flat,
and won't need any cables to connect to my CPU. ;^)

"Pay no attention to that man behind the asbestos curtain!"

Harald Hanche-Olsen

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Dec 11, 1990, 12:27:34 PM12/11/90
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In article <WARREN.90D...@Neon.stanford.edu> war...@cs.stanford.edu (Mark A. Warren) writes:

> What we need is to bag the pixel-based QuickDraw system. Pixels are
>a bad unit to measure with since they come in different sizes.

Forgive me if I am being naive, but isn't Display Postscript just such a model?
Resolution independent representation of the screen. Just mathematical curves
inside your machine; they are converted at display time.

Sure. But non-pixel based graphics models have their own drawbacks:
Try drawing a number of evenly spaced, parallell lines on your
laserprinter some day. One mm apart, width 0.3 points is a good
choice. Look at the output; you will notice that the lines have
different thicknesses, and in fact the effect is quite noticable. If
the line spacing is an integral multiple of 1/300 inch, this does not
happen. This kind of effect will likely be multiplied many times over
on a 72 dpi display.

I am not saying that non-pixel based graphics is a Bad Idea; only that
there is a price to pay for all that mathematical elegance. Of
course, when some day in the future we all have 2400 dpi screens, this
objection will disappear entirely.

- Harald Hanche-Olsen <han...@imf.unit.no>
Division of Mathematical Sciences
The Norwegian Institute of Technology
N-7034 Trondheim, NORWAY

Anton Rang

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Dec 10, 1990, 11:26:03 PM12/10/90
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In article <27...@cs.yale.edu> favorini...@cs.yale.edu (Francis Favorini) writes:
> What we need is to bag the pixel-based QuickDraw system. Pixels are
>a bad unit to measure with since they come in different sizes.

Agreed; we're kind of stuck with it, though, at least with existing
applications. However, a quick glance at Inside Mac V5 reveals a
"fractional horizontal pen position" field, presumably used when
drawing fonts with fractional character widths. Perhaps a future
release of QuickDraw could support fractional horizontal and vertical
positions (FrMoveTo, FrLineTo, etc. -- ugly, but compatible)?

Then again, maybe it's better just to trash the higher-level
QuickDraw code, come up with a nice resolution-independent interface,
use the low-level QD when possible to implement it (saving huge gobs
of code rewrites) and provide a high-level QD emulation. I dunno.
Something should be done by Apple, though, and fairly soon.

Anton

+---------------------------+------------------+-------------+
| Anton Rang (grad student) | ra...@cs.wisc.edu | UW--Madison |
+---------------------------+------------------+-------------+

Mark A. Warren

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Dec 11, 1990, 3:41:40 AM12/11/90
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> What we need is to bag the pixel-based QuickDraw system. Pixels are
>a bad unit to measure with since they come in different sizes.

Forgive me if I am being naive, but isn't Display Postscript just such a model?


Resolution independent representation of the screen. Just mathematical curves
inside your machine; they are converted at display time.

Perhaps NeXT machines are the machines of the future after all (see the latest
comparison in MacWorld).

Mark

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/ \/ \/ \ Mark Warren | Rains Box 12, Apt1D
O / / / _ / war...@ir.stanford.edu | Stanford, CA 94305
/ / / / \/ /-\ /_) | (415) 497-6816
/ (_/\_/\_/ (_/ \___

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_ _ _
/ \/ \/ \ Mark Warren | Rains Box 12, Apt1D
O / / / _ / war...@ir.stanford.edu | Stanford, CA 94305
/ / / / \/ /-\ /_) | (415) 497-6816
/ (_/\_/\_/ (_/ \___

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