🚀 go-pugleaf

ted@helios.ucsc.edu (Sync) writes:

>I'm thinking of getting a new video board for my computer and I'm wondering
>if there is any advantage to getting one that is a Windowz accelerator. I don't
>know if that kind of board is so optimized for Windowz that it will slow up
>other apps, or if it helps all GUI's. Anyone have a clue?

I'm not by any means an expert on this topic, but I believe the "accelerated"
video boards simply provide better performance in the high-resolution video
modes, regardless of which software is being run.  Most of them don't have
any positive effect on a DOS display.  The boards didn't _used_ to be "Windows
Accelerator" boards... they used to be "Graphic Accelerator" boards that were
used for high-end CAD applications and such.  When Windows came along, people
were faced with software where even the low-end applications benefited from
such hardware. :)

As to whether they'd help GEOS... Hmmm.  If they just increase the video 
throughput, they might help a little bit with screen redraw times and such.

-Shag

-- 
birchall@pilot.njin.net, shag@glia.biostr.washington.edu, birchall@njin.bitnet
  Operator of ShagNet - Rutgers/NJIN dialup access for Burlington County, NJ
     Happy and informative user of a PPI 14400 FaxModem and GeoWorks Pro
       Editor of the Queensryche E-mail Digest - "Screaming in Digital"

In article <Jan.27.07.29.04.1993.17178@pilot.njin.net>
birchall@pilot.njin.net (Shag) writes:
>ted@helios.ucsc.edu (Sync) writes:
>
>>I'm thinking of getting a new video board for my computer and I'm wondering
>>if there is any advantage to getting one that is a Windowz accelerator. I don't
>>know if that kind of board is so optimized for Windowz that it will slow up
>>other apps, or if it helps all GUI's. Anyone have a clue?
>
>I'm not by any means an expert on this topic, but I believe the "accelerated"
>video boards simply provide better performance in the high-resolution video
>modes, regardless of which software is being run.  Most of them don't have
>any positive effect on a DOS display.  The boards didn't _used_ to be "Windows
>Accelerator" boards... they used to be "Graphic Accelerator" boards that were
>used for high-end CAD applications and such.  When Windows came along, people
>were faced with software where even the low-end applications benefited from
>such hardware. :)
>
>As to whether they'd help GEOS... Hmmm.  If they just increase the video 
>throughput, they might help a little bit with screen redraw times and such.

The so called Windows accelerator video boards have implemented some amount
of functionality that the MS Windows graphical environment can use, in
hardware, and provides software drivers compatible with Windows.  To take
advantage of any of that extra functionality requires an appropriate driver
to mediate between the system and the hardware.  As many of those hardware
functions have been created specifically for Windows, it may or may not be
appropriate (or even possible) to use those functions for anything else.

Hope that was clear,
		John
		johnm@cory.Berkeley.EDU

P.S.	I speak for the birdies that follow me around.
	GeoWorks speaks for itself.

In article <1k1cldINN8l0@darkstar.UCSC.EDU> ted@helios.ucsc.edu (Sync) writes:
>I'm thinking of getting a new video board for my computer and I'm wondering
>if there is any advantage to getting one that is a Windowz accelerator. I don
>know if that kind of board is so optimized for Windowz that it will slow up
>other apps, or if it helps all GUI's. Anyone have a clue?

If it's a Windows acelerator, it is optimized for Windows.  It's not hard
to optimize for Windows since Microsoft tells you straight out what kind of
graphics functionality Windows expects to have.  That's called a Driver
Specification.

Optimization means that some of the functionality has been moved to hardware,
or less likely, that they worked damn hard to get some of the software-
implemented functionality as absolutely fast as possible :-).  An example
of this would be a hardware-based cursor.  Then all the stuff needed to make
sure that your windows (little w) don't obscure that cute arrow as the mouse
drags it around, or that when the arrow moves the underlying window (little
w) is still intact, has been moved to hardware.

A Windows accelerator won't slow down your other apps.  Basically, your
other apps won't know how to use that graphics board and they'll default
to VGA (or whatever your best STANDARD setting is on your PC.)  It has
ALWAYS been the case that special graphics boards needed special software
for applications to take advantage of them.  This is true whether the
graphics board was optimized for the kind of functionality Windows wants,
or whether its just some generic spiffy graphics board.

So, it won't slow down your other apps.  But it won't help them.  They'll
basically ignore it.  Including other GUI's.  

Other GUI's *could* take advantage of a Windows accelerator if they wrote
their graphics routines to use the same kind of low-level functionality 
that Windows does.  I even suggested this once to a GUI company.... it 
would give people instant access to a lot of existing hardware.  But it's
anathema from a marketing point of view because it concedes that most 
(hardware, in this case) vendors see Windows as the dominant GUI of the
future. 

Lea

The accelerated video boards usually have an on board graphics processor that is used to execute graphics primitives. The primitives vary depending on the board. 

Some of these cards provide for a hardware cursor. (* note that some other,
so-called non-accelerated boards do this as well, such as the Video-7 1024i *) 

Bitblitting operations, pattern fills, line-drawing, screen clearing,
text-clipping and more are supported by many of these accelerator cards.

Since I know that GEOS at least uses a cursor, and it probably makes use of
functions such as line drawing and bit blitting, it should be possible to
develop a version of GEOS that could use hardware video features. I don't know
if hardware support could be incorporated with the current video driver support.

Many of these boards (the TMS boards, the 8514 clones) were designed for CAD and
only later used to accelerate windows.

Some of these boards have been criticized (the S3 based products in particular)
because they actually slow down performance in standard VGA modes. This could
actually translate to slower GEOS performance. S3 products are probably the most
widely supported accelerator products aside from, perhaps, the 8514. 

If you are looking for a card that provides decent VGA performance and gives some
windows acceleration, a cost-effective solution is to purchase an accelerator
board based on the Western Digital (Paradise) accelerated chipset. (Ex: Diamond
Speedstar 24x) This chipset can be found in boards costing considerably less
than $200, and accelerates a few of Windows most important functions. (no line
drawing though..) This chipset also remains partially compatible with the older
Paradise SVGA chipsets, and supports 640x480x16.8 Million colors and
800x600x65536 colors in addition to the (almost standard) 1024x768x256 and
1280x1024x16. Note: in 24 bit mode, these cards are only really useful as
framebuffers. 
-- 
******************************************************************************
* Dan Galpin                                            galpin@cats.ucsc.edu *
******************************************************************************