1. RE: [DOS] graphics problem
hi vince
i don't have an answer, but i can join the call for help. i've spent a
lot of time trying to track this down. your post confirms my view that
it is a problem with the way the in-built routines, pixel() or
get_pixel(), map the pixel locations and/or the palette.
the problem only occurs on some machines (maybe just yours and mine!).
it doesn't happen on the machine at my other office. the problem
computer has an ati-ragepro card of about 1998 vintage.
on the problem machine, the effect is easiest demonstrated by running a
program that uses jiri's widgets in a 256-color mode, because the
transparent mouse (rat.e) routines use a xor method that leaves a trail
behind the mouse in all 256-color modes (and not in 16-color modes). i
have constructed demos to highlight this effect comparing the xor
display to an ordinary display. the xor method uses pixel() and
get_pixel().
this also allowed me to visually map the problem areas of the screen by
running the mouse over the screen. there are parts down the right side
and top that calculate the values correctly (no trail behind the mouse).
these parts are clearly delineated with a straight boundary. for this
reason, i suspect that your hunch, that the routines use the values of
the "scrunched" screen, may not be correct, as the problem areas do not
appear to correspond with the area that gets "scrunched" with vesa off.
my own conclusion was that some video cards and their drivers store the
screen values for different parts of the screen in non-standard memory
locations, and the windows driver translates this for windows, but not
for dos. i was intending to look for a dos driver for this card.
i'd be happy to hear whether robert can suggest a reason for this, since
it seems to depend on the source code of the in-built pixel routines.
but i doubt he can find a machine that will duplicate it. jiri tells me
he has never seen the problem on any machines, and he's tried plenty
over the years.
cheers
tacitus
Vincegg at AOL.COM wrote:
> Hello,
>
> I was wondering if someone might know an answer to this problem. I want
> to
> use video mode 257 but when I try to use it the displayed image appears
> jumbled and compressed to just the upper section to the screen. Fine,
> so I
> add use_vesa(1) to my program and displaying procedures (pixel,
> draw_line,
> display_image and such) work fine. But, get_pixel and the dependant
> save_image seem to be getting their image info not from the corrected
> display
> but the scrunched pre-use_vesa() image. Does anyone know why it's doing
> this
> or better yet how to get around it? Thanks for any info.
>
> Vince
>
>
2. RE: [DOS] graphics problem
Vincegg at AOL.COM wrote:
> Hello,
>
> I was wondering if someone might know an answer to this problem. I want
> to
> use video mode 257 but when I try to use it the displayed image appears
> jumbled and compressed to just the upper section to the screen. Fine,
> so I
> add use_vesa(1) to my program and displaying procedures (pixel,
> draw_line,
> display_image and such) work fine. But, get_pixel and the dependant
> save_image seem to be getting their image info not from the corrected
> display
> but the scrunched pre-use_vesa() image. Does anyone know why it's doing
> this
> or better yet how to get around it? Thanks for any info.
>
Vince:
Your videocard my not be 100% vesa compliant. Sometimes the code
in the video roms is not always correct. You can try using a
different video card or see if your video card comes with a
DOS VESA driver that can be installed.
Bernie
3. RE: [DOS] graphics problem
tacitus wrote:
> the problem computer has an ati-ragepro card of about 1998 vintage.
tacitus,
Following on what Bernie suggested: Have you tried the DOS VESA BIOS
Extension from ATI?
http://support.ati.com/products/pc/ragepro/ragepro_drivers.html
-- Brian
4. RE: [DOS] graphics problem
- Posted by Vincegg at AOL.COM
Sep 05, 2001
Bernie:
My graphics chip is built into the motherboard (I know, me=idiot) so swapping
cards (had I one to swap) won't help... I think. :o)
Brian:
Thanks for the link. The chip is Rage IIC and the driver is current so no
help there.
Tacitus:
I have several games including Rollercoaster Tycoon which use that resolution
and color depth and they work fine so I know there has to be some kind of
solution to this problem. Maybe I'll have to wait until the Euphoria source
code is available in order to find the correct answer.
Vince
5. RE: [DOS] graphics problem
Vincegg at AOL.COM wrote:
> Bernie:
> My graphics chip is built into the motherboard (I know, me=idiot) so
> swapping
> cards (had I one to swap) won't help... I think. :o)
>
> Brian:
> Thanks for the link. The chip is Rage IIC and the driver is current so
> no
> help there.
>
> Tacitus:
> I have several games including Rollercoaster Tycoon which use that
> resolution
> and color depth and they work fine so I know there has to be some kind
> of
> solution to this problem. Maybe I'll have to wait until the Euphoria
> source
> code is available in order to find the correct answer.
>
>
Vince:
When you run Rollercoaster Tycoon you are using a WINDOW's
DRIVER, Your problem is with DOS VESA DRIVER which is not
the same driver so check for a DOS VESA DRIVERat the WEB Site.
On most motherboards it is possible to disable the on-board
video and insert a videocard in a slot.
Bernie
6. RE: [DOS] graphics problem
OH JOY! OH RAPTURE!
THANX, BRIAN AND BERNIE!!
I now have the best-looking widgets in town.
The dos driver indicated by brian works. It is a TSR specifically
designed to allow various ati ragepro cards to use the vesa standard in
dos.
The documentation details the advanced switches to use in various
situations. for my card, the switches 's' (for single-window only mode)
and 'vga' were correct. the 'vga' switch is a default so i didn't need
to actually type that. these switches are specifically documented for
problems with pointer devices.
running the program at the end of execution with the 'u' switch unloads
it from memory. if you don't want to load this driver every boot, i've
tested it in both bat files and as the first argument of a system()
call, and both work.
cheers
tacitus
Bernie Ryan wrote:
>
> Vincegg at AOL.COM wrote:
> > Bernie:
> > My graphics chip is built into the motherboard (I know, me=idiot) so
> > swapping
> > cards (had I one to swap) won't help... I think. :o)
> >
> > Brian:
> > Thanks for the link. The chip is Rage IIC and the driver is current so
> > no
> > help there.
> >
> > Tacitus:
> > I have several games including Rollercoaster Tycoon which use that
> > resolution
> > and color depth and they work fine so I know there has to be some kind
> > of
> > solution to this problem. Maybe I'll have to wait until the Euphoria
> > source
> > code is available in order to find the correct answer.
> >
> >
> Vince:
> When you run Rollercoaster Tycoon you are using a WINDOW's
> DRIVER, Your problem is with DOS VESA DRIVER which is not
> the same driver so check for a DOS VESA DRIVERat the WEB Site.
> On most motherboards it is possible to disable the on-board
> video and insert a videocard in a slot.
> Bernie
>
>
