I have been looking for the graphics card that is most widely used,
because if I support it in my OS then more people will be able to use it, which increases the public abuility to create drivers for difrent video cards.

would someone please let me know what the most widely
used Video Card is that can be easaly supported by an OS.

GeForce and radeon cards, I would say

Maybe a better way to do it would be to design a driver that adapts universally to different cards based on the values contained in the registers, when you detect the card. That way a person using your OS could still install the OEM drivers if they chose, and you could save yourself some typing

same here f0dder, i would say GeForce and Radeon

jdawg say that :



I think that designing driver that support from VESA1 to VESA3 standard will be the best way to support all commonly used cards ( even 10 years old like old S3, CirrusLogic or Trident ( VESA1) ).
Driver that support VESA now we can name OEM driver

( WindowsXP OEM drivers it's writed with that way (i think) )

Also is good think to support RADEON and/or GeForce/RIVA cards

By volume of parts shippped, it's Intel, followed by nVidia and ATi. Yes those crappy onboard integrated graphics make up a lot of volume! (That includes, PC's, laptops, servers, etc).

However the OP is better sticking with VESA, as getting docs from ATi or nVidia can be next to impossible, well at least for the current cards/chipsets.

I wrote that incuding VESA standard becouse i think that is it's commonly used in new graphic cards, but when i saw SIS's card integrated with SIS mainbord i forgot about it. This card have AGP,a lot of memory and many more, but can't even handle simple Vesa Svga mode ( in DOS ) by using this simple code:


I think that most compatible( and old-card compatible) will be 13h mode with virtual_screen_scrolling, or MODE-X support ( can handle up to 400x600 or square_ratio_400x300 ) with Virtual_screen

What is Virtual screen:


more old compatible card support can't be done ( what about old HERCULES cards )

I may well be in error, for example, I have not checked the sis web site, but, in my opinion, sis uses either trident, or s3, graphics controllers, both of which, I believe, do support svga modes, but perhaps with a limitation on the color quantity. For sure, the trident at least, will support 1280 x 1024 with 8 bits for color.

When i think about SIS card - i thinked about SIS 6326 AGP integrated with SIS's mainboard ( I don't remeber what model ) - it can't work with Svga modes in DOS, also in Ms Win can't run modes < 640x480.

Why this card can work with for example 640x480x16bit mode in windows, but can't do in DOS ?

Answer: Because VGA Bios witch is loaded when compuer start can't work in this resolutions. Windows's SiS Driver don't use VGA BIOS for this resolution - it using their own part of code witch is accesing directly to SIS card registers.

To get DOS SVGA modes on this card you must use for example SciTech drivers, or VESA driver manufactured by SIS - part of this driver overwriting previus writable VGA parts of BIOS - so DOS calls to change mode may be done.
To write own display driver programmer must know all about SIS card registers and more.

Problem with no low_modes in Windows can be solve be updating display driver.

What I meant is that when you first send an interrupt to any port or address you supply it with a function code. Depending on what the function code is you recieve different information back from that port or address. I'm only saying that a thourough probe of the card before a driver is built would provide a much more accurate driver for it. That way you only provide things that the card would natively support.

ATA, GeForce, nVIDIA

Many people forget to check the video mode list before setting a video mode. Also some cards like ATI and SIS have non-standard i/o ports, so to get them to work properly, legacy bios or vesa bios interrupts are a must.

an old school generic 'vbeaf.drv' works a treat for o/s dev, but good ones are hard to find now.

checkout www.vesa.org for the free specs...

I think, if you want to do hardware acceleration, go for some of Intel's GPU docs to get an idea as to how they implement it, as they have documentation which ATI (AMD now?) and nVidia refuse to give out. It might be able to give you an idea as to how you're going to go about this feat.

..

nowadays...
by contiguous coding, 16 hours a day, 7 days a week, 4 weeks a mounth, i think, 1 year

Creative work isn't like a work in a coal-mine. There are necessary breaks for rest. In other case it won't be "creative" work, but drudgery.

so, if you make some pauses, multiply the time by 3 or 4

because the time to re-dive into this no human work. it needs a constant concentration.

Right. I especially agree with this "coefficient" (3-4 times).

From my private observations I can formulate such remark: it's good to work very hard for some time (say, 1-2 weeks) on some problem, but after you have to "drop & forget" it for some time (say, month). After this time some unsolved ("impossible") problems become trivial.

sleeping helps a lot to find solutions...
but before to sleep, you shall think about the problem to solve.

Actually ATI and nVidia both incorporate UDA (Unified Driver Architecture) which in turn means write-once-use-everywhere principle. They've got all the necessary info in that "tiny" (~40MB) packages. Of course for MenuetOS (just an example) you can forget all those profile thingies like which settings to apply on World of Warcraft
Then you can loose all the support for DX/OGL at first to get the driver working with only primitive blit and sprite support.
... 300KB driver easy

BUT, the only problem is, there is nowhere to start from