UNIX for Dummies Questions & Answers

Video doesn't work that way. Text mode is text. Byte 'a' in 0xb800:0000 (if my memory serves me correctly) shows an 'a' in the very upper left of your screen, messing with the contents of byte 0xb800:0001 will change that one letter's color. You don't have finer grained control than that, except perhaps by changing the meaning of 'a' in the video card's character set, and that's extremely limited.

To draw graphics in DOS you had to talk to the video card itself and change the video mode. Then the way the video hardware interprets the contents of memory would change. In mode 13 -- 320x240 resolution 8-bit color -- the first byte in video memory would be the very upper left pixel, the second would be a pixel one to the right of it, and so on. (This is also how svgalib works, though controlling the video card in UNIX is much less direct than in DOS.)

If DOS itself was stuck in a video mode that wasn't text, it could still print text, but only because it used small programs embedded inside the BIOS itself to do so. Very slow, but works in nearly any video mode.

Why not?

Perhaps if you were more specific about your goal here? not "how to do graphics in text", which doesn't make much sense no matter how you explain it. But what problem you're trying to solve with graphics, on what kind of system.

It'd also help to know what you mean by "terminal". A raw text console of some sort, or a terminal running inside an X server, or what?

I see. Thank you.

These SVGALIB programes need old linux kernel and some sole lib files. I can't event compile them.

Compile them in what? What is your system?

svgalib has changed along with everything else in Linux as time goes by, ancient svgalib-using programs may no longer work with modern svgalib. But svgalib definitely still exists. There's also alternatives like console framebuffer, and (I think) directfb.

libSDL is a graphics library that can be built to support svgalib, console frame buffer, and tons of video libraries/methods I've never even heard of. (all of them optional. It can be built without video support entirely, though it'd be pretty useless without it...) Games use SDL the same way no matter what video backend SDL is built with. And there's lots and lots and lots of SDL games, new and old. If you can get SDL and framebuffer working on your system you might find a world of games. Heck, even X11 itself can be built to use an SDL backend these days.

Not using an X server backend for SDL means the video almost certainly won't be hardware-accelerated, though.

In the old days the game Hack and later NetHack used ASCII glyphs to represent game elements "graphically" - not sure if you consider that picture based.

My system is

Code:

Linux Arch 2.6.33-ARCH #1 SMP PREEMPT Thu May 13 12:06:25 CEST 2010 i686 Pentium(R) Dual-Core CPU E5300 @ 2.60GHz GenuineIntel GNU/Linux

I haven't find a SDL game can compile on my system.
PS: my system doesn't have X.

It might, just might, help if you installed SDL first

It'd also really help if you got framebuffer or something working for SDL to use.

It'd also really help if you described in what way things "couldn't x". Errors? Which errors? Something wouldn't work? Which something? And on, and on, and on. You really never gave us a straight answer on what you wanted, I had to deduce it from clues, and it's still possible that I'm wrong.
That tells me what kernel you're using. The kernel is the 3-meg file that loads on boot. About absolutely everything else on your system, I still know utterly nothing.

I just want a small pixel based game that can run in a TTY terminal.
I mean I don't have X installed, and I don't want it installed, so no error with it.
Also I have libSDL installed.