Printers seem to have settled upon a vector way to communicate things to
them: the postscript language. I can see this has many advantages plus
serves to compress the information transmitted in most cases. Cases that
involve geometric primitaves, not photos etc., of course.

I wonder why "monitors" have not evolved to use a similar language? Most
monitors (as far as I know) still rely on a raster grid being refreshed at
intervals.

Is raster for visual-displays and vector for physical-printouts make sense
for some fundamental technological reason. Or am I again ignorant, and
there are vector implementations of languages to communicate with monitors
too?

--
Rahul

On Wed, 16 Jul 2008 17:45:47 +0000, Rahul wrote:

> Printers seem to have settled upon a vector way to communicate things to
> them: the postscript language. I can see this has many advantages plus
> serves to compress the information transmitted in most cases. Cases that
> involve geometric primitaves, not photos etc., of course.

Normal PostScript is not 'compressed' at all. It is actually plain text
which you can easily read - well, maybe not so easily - it takes a little
studying to figure it out.

>
> I wonder why "monitors" have not evolved to use a similar language? Most
> monitors (as far as I know) still rely on a raster grid being refreshed
> at intervals.

Primarily because that is how they actually work. Have you ever heard of
'Disply PostScript'?

>
> Is raster for visual-displays and vector for physical-printouts make
> sense for some fundamental technological reason. Or am I again ignorant,
> and there are vector implementations of languages to communicate with
> monitors too?

ray <ray@zianet.com> wrote in news:6e6tflF5lljrU2@mid.individual.net:

>
> Primarily because that is how they actually work. Have you ever heard
> of 'Disply PostScript'?

Thanks Ray! Actually, I had never heard of that. Just googled the term up.

>
> Normal PostScript is not 'compressed' at all. It is actually plain
> text which you can easily read - well, maybe not so easily - it takes
> a little studying to figure it out.

Sorry. I did not mean "compressed" in the usual sense of the term but
"compressed" vis a vis the alternative of expressing the output as a bitmap
or similar format. Just wanted to imply that vector formats are less
information-heavy than raster.

--
Rahul

Rahul <nospam@nospam.invalid> writes:

> Sorry. I did not mean "compressed" in the usual sense of the term but
> "compressed" vis a vis the alternative of expressing the output as a bitmap
> or similar format. Just wanted to imply that vector formats are less
> information-heavy than raster.

Data-heavy, at least. Consider PostScript an apt description language
and look up Kolmogorov complexity under information theory. (-: That's
how compression fits in.

Mark

On Wed, 16 Jul 2008 17:45:47 +0000, Rahul wrote:

> Printers seem to have settled upon a vector way to communicate things to
> them: the postscript language. I can see this has many advantages plus
> serves to compress the information transmitted in most cases. Cases that
> involve geometric primitaves, not photos etc., of course.

This is not really correct. All modern printers are of a raster kind.
Most have a built-in software front-end that takes vector data and
rasterizes it to become suitable for output.

> I wonder why "monitors" have not evolved to use a similar language? Most
> monitors (as far as I know) still rely on a raster grid being refreshed
> at intervals.

Displays are raster devices, like printers. At least two vector front-
ends are available: OpenGL and Direct3D. Rasterization is done by the
graphic card's GPU.

--
Vladimir

Vladimir Florinski <vflorins@ucr.edu> wrote in news:pan.2008.07.17.01.53.30
@ucr.edu:

> This is not really correct. All modern printers are of a raster kind.
> Most have a built-in software front-end that takes vector data and
> rasterizes it to become suitable for output.
>
> Displays are raster devices, like printers. At least two vector front-
> ends are available: OpenGL and Direct3D. Rasterization is done by the
> graphic card's GPU.
>


Thanks Vladimir. True; but doesn't it make sense to rasterize as close to
the final device as possible? Like printers do. That way the data pipeline
can be kept as compact as possible most of the way. Opens the possibility
of using low-bandwidth pipelines like USB and bluetooth. We have USB
printers but few USB monitors, as yet.

--
Rahul

Rahul <nospam@nospam.invalid> wrote:
> USB printers but few USB monitors, as yet.

VT220 with a Serial/Bluetooth dongle?

Chris

Rahul wrote:
> Vladimir Florinski <vflorins@ucr.edu> wrote in news:pan.2008.07.17.01.53.30
> @ucr.edu:
>
>> This is not really correct. All modern printers are of a raster kind.
>> Most have a built-in software front-end that takes vector data and
>> rasterizes it to become suitable for output.
>>
>> Displays are raster devices, like printers. At least two vector front-
>> ends are available: OpenGL and Direct3D. Rasterization is done by the
>> graphic card's GPU.
>>
>
>
> Thanks Vladimir. True; but doesn't it make sense to rasterize as close to
> the final device as possible?

That would require to put the graphics card in the display, while on
low-end computers, some of the graphic functionality is performed by the
"main" CPU, or some of the RAM used by the GPU is part of the standard
RAM. Kiss bye-bye to inexpensive computers, since it makes the
full-fledged graphics card mandatory.

And manufacturers have to offer a very large range of displays,
considering the possible mix of screen size and GPU power.

And you would have to worry about the software release used in the
display.

And anyway, the bandwidth required between the CPU and the graphics card
in a modern PC is also very high, around 4Gbytes/sec so moving the card
to the display may not improve anything.

On 16 Jul 2008, Rahul wrote:

> I wonder why "monitors" have not evolved to use a similar language?
> Most monitors (as far as I know) still rely on a raster grid being
> refreshed at intervals.

Old NeXT stations used display postscript. The earliest SGI IRIX
machines did, too. (IRIX 4 -- I don't think they did after IRIX 5.)
I don't know about Sun, but some of those from the same era might have
also used display postscript.


--
barutanseijin@gmail.com

On Thu, 17 Jul 2008 01:53:30 +0000, Vladimir Florinski wrote:

> On Wed, 16 Jul 2008 17:45:47 +0000, Rahul wrote:
>
>> Printers seem to have settled upon a vector way to communicate things
>> to them: the postscript language. I can see this has many advantages
>> plus serves to compress the information transmitted in most cases.
>> Cases that involve geometric primitaves, not photos etc., of course.
>
> This is not really correct. All modern printers are of a raster kind.
> Most have a built-in software front-end that takes vector data and
> rasterizes it to become suitable for output.
>
>> I wonder why "monitors" have not evolved to use a similar language?
>> Most monitors (as far as I know) still rely on a raster grid being
>> refreshed at intervals.
>
> Displays are raster devices, like printers. At least two vector front-
> ends are available: OpenGL and Direct3D. Rasterization is done by the
> graphic card's GPU.

Oh, yes. OpenGL - I had forgotten about that. I did have to learn it a few
years ago, but always considered it a PITA. But it does fill the bill here.