OSDev.org

iansjack wrote:

Hopefully you recognize overkills when you see them.

OK; good joke while it lasted.

You took all of us in, but enough trolling.

I am not trolling with this. However, I admit that some aspects of this are somewhat tongue-in-cheek but the main concept of this project is not a joke (Long Mode obviously was).

This whole topic is not the only project plan I am working on. I am gathering different ideas and this is one of them. Some ideas are discarded and some are developed further. Chances for this being developed further decrease every minute.

Before I go into some of the technical issues, I strongly recommend that you reconsider. Given that DOS gamers (are there any left?) are not your target audience, providing this port would not make any sense. People buy games for their content, not the other platforms to which the game was ported. Imagine you're a PlayStation fan but can't afford such a console so instead you play games on your PC. How does the fact that a PC game is also available for the PlayStation influence your choice of whether or not to purchase it? I'm not an expert in marketing but I bet that "People who appreciate that SomeGame is also available for DOS" is not a valid audience.

Antti wrote:To be somehow realistic, Windows-, Mac-, Linux-ports of this game are also released and they are developed concurrently with the MS-DOS version. Cross-platform libraries are not used and all the ports are native.

Antti wrote:The game itself must be designed to be very portable.

That is contradictory. You should definitely not ignore all the progress that the discipline of software engineering has made during the past 40 years. I will list some of the disadvantages of not using cross-platform libraries: increased development cost, increased development time, lots of duplicated code, decreased maintainability, much more error-prone. Advantages: none.

Antti wrote:I did mention about the possibility to use VESA modes for graphics. After reconsidering it, I think that it might not be a good idea. Probably the game engine should only use the 320x200 graphics because that is what the games basically used back then.

Back when, precisely? Here's a screenshot of Duke Nukem 3D for DOS running at 640 x 480. In fact, the biggest reason for which VBE/Core (which you mistakenly call VESA, the name of an oranization) was introduced was that so many DOS games before it had to ship with their own SVGA video drivers (see some of the disadvantages above). However, one disadvantage of VBE/Core is that, for some things, it's not as fast as native video drivers. VBE/AF fixes part of the problem but is not widely supported in firmware.

Heck, even VGA supports 320 x 240 x 256_colors_at_a_time_but_with_a_palette_of_262144_that_can_be_used.

Love4Boobies wrote:

Antti wrote:To be somehow realistic, Windows-, Mac-, Linux-ports of this game are also released and they are developed concurrently with the MS-DOS version. Cross-platform libraries are not used and all the ports are native.

Antti wrote:The game itself must be designed to be very portable.

That is contradictory. You should definitely not ignore all the progress that the discipline of software engineering has made during the past 40 years. I will list some of the disadvantages of not using cross-platform libraries: increased development cost, increased development time, lots of duplicated code, decreased maintainability, much more error-prone. Advantages: none.

Yes, there is some contradictory between these two posts. The portability here means that the game data is easily retrievable. This means that making a game engine that uses the game data should be made as easy as possible. The engine itself could be very non-portable and I should have emphasized this fact a little bit more.

The game should not require much from the hardware. Basic user inputs, sound (difficult), and software rendering etc. This also means that the game runs slowly and the game idea should be built upon this assumption.

Another challenge with write DOS game on modern machine is drivers.
You need USB joystick/HID/mouse, sound chip(do modern sound chip operate in SB compatible mode?)

Things add up and you may as well got an OS of your own someday, you then aware you only launch your environment from DOS and require less DOS function, you may as well drop support of DOS.

bluemoon wrote:Another challenge with write DOS game on modern machine is drivers.
You need USB joystick/HID/mouse, sound chip(do modern sound chip operate in SB compatible mode?)

The game should not need any special drivers for input: only keyboard is needed. The sound is a difficult one and yet very important.

As I am continuously improving this concept, there can be some inconsistencies between my newer posts and the original one. This whole thing whatsoever is very well comparable to the hobby operating system developing. It does not make much sense but it is fun. Maybe I exaggerated the commercial success. I would be happy even if this project had zero profit. And yes, the target audience for this game might be people how are interested in the platform the game is targeted.

Antti wrote:The game should not need any special drivers for input: only keyboard is needed.

Showstopper right there. Have you *ever* played a keyboard-only game that was fun? Heck, even M.U.L.E. had joystick support...

Solar wrote:Have you *ever* played a keyboard-only game that was fun?

VI adventure!

Solar wrote:

Antti wrote:The game should not need any special drivers for input: only keyboard is needed.

Showstopper right there. Have you *ever* played a keyboard-only game that was fun? Heck, even M.U.L.E. had joystick support...

A good question. Almost all the good ones have the joystick support. Most of the time I have used just the keyboard.

Solar wrote:Have you *ever* played a keyboard-only game that was fun?

Nethack? Nibbles? And of course, many many more since the TI-83 and the early smartphones were all keyboard-only.

I'm not a joystick user, so for many of the more famous EGA-era games I couldn't begin telling which ones had some (borked) support for them.

The ultimate simple example of this game concept would be a text adventure. The game engine would be rather easy to do for all the supported platforms.

The actual adventure is packed in a resource file and the game engine interprets that. In this case, maybe it would be wise to obfuscate the file content a little bit. Some modified compression algorithm would be enough.

Solar wrote:

Antti wrote:The game should not need any special drivers for input: only keyboard is needed.

Showstopper right there. Have you *ever* played a keyboard-only game that was fun? Heck, even M.U.L.E. had joystick support...

First Gothic was only playable when using only keyboard... and it's not that old and definitely fun.

The only advantage of a DOS-only game I can think of, is that there is a DOS emulator for virtually every platform, making ports unnecessary.

BTW I love to play DOS games but I'm afraid that a new game will be like the new Volkswagen Beetle - not like a Beetle at all.

Antti wrote:Yes, there is some contradictory between these two posts. The portability here means that the game data is easily retrievable. This means that making a game engine that uses the game data should be made as easy as possible. The engine itself could be very non-portable and I should have emphasized this fact a little bit more.

Could but shouldn't, unless you there's a very good technical reason why you're unable to.

Antti wrote:The game should not require much from the hardware. Basic user inputs, sound (difficult), and software rendering etc. This also means that the game runs slowly and the game idea should be built upon this assumption.

For sound, the firmware solution would be VBE/AI, but just like VBE/AF, it is not widely supported. The software solution is to implement drivers for at least the more popular sound cards. There's Sound Blaster, with which almost all sound cards from the DOS era were compatible and even much later ones. Incompatible but still pretty popular were AdLib and Gravis Ultrasound. You may also want to look into PIT + PC speaker but not too many "contemporary" systems have that---after all, your target is systems that people still have today. Today, AC'97 and HDA cover most PCs.

bluemoon wrote:

Solar wrote:Have you *ever* played a keyboard-only game that was fun?

VI adventure!

Hobbes wrote:BTW I love to play DOS games but I'm afraid that a new game will be like the new Volkswagen Beetle - not like a Beetle at all.

That is a very common problem. It may be the one of the biggest challenges for this project.

Love4Boobies wrote:For sound, the firmware solution would be VBE/AI, but just like VBE/AF, it is not widely supported. The software solution is to implement drivers for at least the more popular sound cards. There's Sound Blaster, with which almost all sound cards from the DOS era were compatible and even much later ones. Incompatible but still pretty popular were AdLib and Gravis Ultrasound. You may also want to look into PIT + PC speaker but not too many "contemporary" systems have that---after all, your target is systems that people still have today. Today, AC'97 and HDA cover most PCs.

The sound support for Sound Blaster and PC speaker may be the way. I don't think it is necessary to worry whether contemporary systems have a support for these or not. The game should follow the same standards as back then.

What this mystical "back then" means? I am not quite sure but maybe the DOS game years 1992-1994. If doing the real old-school, then maybe early PC years should be included.

Antti wrote:The sound support for Sound Blaster and PC speaker may be the way. I don't think it is necessary to worry whether contemporary systems have a support for these or not. The game should follow the same standards as back then.

Right, I forgot this was a commercial game for computers that almost no one has anymore.

Antti wrote:What this mystical "back then" means? I am not quite sure but maybe the DOS game years 1992-1994. If doing the real old-school, then maybe early PC years should be included.

Well, you mentioned that you want the look and feel of DOS games back then but some of them did have better resolutions and color depths.

Anyway, it doesn't seem like you really know what you want so far, which is why this thread is going nowhere. All you have so far is a bad idea for a commercial product.