Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
LogicDeLuxe

What's this "store demo"?

Recommended Posts

If you remove the MAP01 lump from your doom2.wad, Doom will start up and play through the demo loop, but all input will be disabled. It seems to be there so that you can install Doom on computers on display in stores as a demo, without allowing customers to actually play.

Share this post


Link to post

Couldn't the guy in charge just unplug the mouse and keyboard if he really wanted to prevent people from playing?
Also, equipments in stores are usually installed ready to use so potential customers can try them out. What's the point in preventing them to do so?

Share this post


Link to post
LogicDeLuxe said:

Couldn't the guy in charge just unplug the mouse and keyboard if he really wanted to prevent people from playing?
Also, equipments in stores are usually installed ready to use so potential customers can try them out. What's the point in preventing them to do so?


1993 was a long time ago...

Share this post


Link to post
LogicDeLuxe said:

Couldn't the guy in charge just unplug the mouse and keyboard if he really wanted to prevent people from playing?
Also, equipments in stores are usually installed ready to use so potential customers can try them out. What's the point in preventing them to do so?

Yeah, all valid questions. We have no idea what the situation was that required this feature be added. Presumably it made sense to someone.

This is the code from the Doom source:

void D_ProcessEvents (void)
{
    event_t*    ev;
    // IF STORE DEMO, DO NOT ACCEPT INPUT
    if ( ( gamemode == commercial )
         && (W_CheckNumForName("map01")<0) )
      return;
[...]
I should point out that my explanation above is only my interpretation of what the purpose of this appears to be, but it looks pretty self-explanatory to me.

Share this post


Link to post
Ultraboy94 said:

could you do the same with PWADS that have demos in?

No.

Share this post


Link to post

Actually you can, you just need to make sure you remove any MAP01 lump in the PWAD as well.

Share this post


Link to post

Or he didn't interpret the question in the same way. You can't make Doom enter "store demo" mode by loading a PWAD with demos if the IWAD isn't "crippled".

Share this post


Link to post

Indeed. It's only the main wad that counts and demos can be replaced via pwads just like any other resource, if you want. Have a wad with DEMO1, DEMO2, DEMO3 or you can also say -playdemo DEMO1 and so on, if you have a .lmp file that is.

Share this post


Link to post

But presumably, if you have a crippled IWAD and load a PWAD which contains a MAP01, then you get the normal behavior rather than the "store demo" one.

Share this post


Link to post
LogicDeLuxe said:

Couldn't the guy in charge just unplug the mouse and keyboard if he really wanted to prevent people from playing?


And then how could the computer even boot, unless the BIOS allowed for keyboardless operation? (something that's still only found in top-of-the-line servers)

"No keyboard present. Press F1 to continue."

(This only makes sense if you're using a KVM/switch and you had it turned elsewhere during boot).

Share this post


Link to post
Maes said:

And then how could the computer even boot, unless the BIOS allowed for keyboardless operation? (something that's still only found in top-of-the-line servers)

You sure about that? I have several PCs from low to medium-end from the mid-90s to today, they all allow headless operation.

Share this post


Link to post

Step 1. Boot computer.
Step 2. Start DOOM.
Step 3. Unplug keyboard and mouse.
Step 4. Open shop to customers.


That said it's not complicated either to leave the mouse and keyboard plugged, but inaccessible to the public. The only thing they need to see is the screen, everything else can be locked in a cupboard or something.

Share this post


Link to post
MikeRS said:

You sure about that? I have several PCs from low to medium-end from the mid-90s to today, they all allow headless operation.

Same here. I used an old Pentium II box last year to steal wifi and forward the connection to the rest of my home network. It had no problem booting into linux without a keyboard or monitor. It would have been a huge pain in the ass to haul peripherals over to the room it was in every time I wanted to power up.

Share this post


Link to post

None of this is mentioning anything about the fact that W_CheckNumForName was a slow method to call in vanilla DOOM and that this "clever" little modification is calling it constantly from the main loop of the game over and over for the same constant result.

Really good programming :P

Share this post


Link to post
Maes said:

"No keyboard present. Press F1 to continue."

The last time I've seen this was on an old 80486 PC with Amibios. This silly message was part in many joke collections since then.

Quasar said:

None of this is mentioning anything about the fact that W_CheckNumForName was a slow method to call in vanilla DOOM and that this "clever" little modification is calling it constantly from the main loop of the game over and over for the same constant result.

Really good programming :P

I didn't check the code, but my first guess was, that this check is done when opening the menu. Or while loading the keyboard assignments of the config file. It sure would be unnecessary to check this all the time during playing.

Share this post


Link to post
Gez said:

Step 1. Boot computer.
Step 2. Start DOOM.
Step 3. Unplug keyboard and mouse.
Step 4. Open shop to customers.


That said it's not complicated either to leave the mouse and keyboard plugged, but inaccessible to the public. The only thing they need to see is the screen, everything else can be locked in a cupboard or something.


Some shop owners wouldn't want to bother doing anything to the mouse and keyboard, especially if the computer contained another software demo that the owner would want to run at another time that made use of the keyboard and mouse.

I know someone's going to say "well, that owner could just plug the keyboard and mouse back in". As I said before, some owners wouldn't want to bother doing ANYTHING to the mouse and keyboard, especially if the computer could be hidden somewhere where the PS/2 ports aren't that easily accessable. (Not to mention that reaching to the back of the computer and plugging in a PS/2 port isn't as easy as nowadays with the USB)

Also, fraggle, Chocolate Doom allows the ALT-F4 key combination and window closing in "store demo mode", but cannot do anything after the "are you sure?" message. Either allow the user to exit by alt-f4 or window closing or disable them.

Share this post


Link to post
fraggle said:

If you remove the MAP01 lump from your doom2.wad, Doom will start up and play through the demo loop, but all input will be disabled. It seems to be there so that you can install Doom on computers on display in stores as a demo, without allowing customers to actually play.


Actually it seems to make more sense that the initial reason was for to watch demos, but that the reason you put is absolutely optional. and I doubt it being 1993 was a definite reason that removing the keyboard and mouse would pose a problem and doom would need this feature built in its place.

Share this post


Link to post

Funny thing is, in 1993, Doom tended not to be in stores. The SW episode was generally found on a BBS or a magazine disk and the full version was ordered direct.

Share this post


Link to post

Now, when I think of it, unplugging mouse and keyboard seems too obvious. I guess, they crippled the IWAD to discourage piracy.

Enjay said:

Funny thing is, in 1993, Doom tended not to be in stores. The SW episode was generally found on a BBS or a magazine disk and the full version was ordered direct.

Does MAP01 and doom2.wad mean anything to you?

Share this post


Link to post
MikeRS said:

You sure about that? I have several PCs from low to medium-end from the mid-90s to today, they all allow headless operation.


And I serviced literally dozens of PCs ranging from socket 7 mobos to Core Duos, and keyboardless operation was a frivolous optional only found on server-class mobos, and "brand" PCs like Dell etc.

In any case, not something you would find on a mainstream built PC in the days where Doom was likely to be found on a store's shelves, let alone being demoed.

Nes said:

I know someone's going to say "well, that owner could just plug the keyboard and mouse back in".... PS/2 ports


And there's the killer. DIN and PS/2 ports are NOT hot-pluggable. I once reported someone because his department kept asking for replacement keyboards and mice all the time. When I asked to see for myself WTF were they doing, I saw the dullard had a habit of removing the mice and keyboard "after use"...with the computer still on -_-

Needless to say how that ended up....

Share this post


Link to post
Enjay said:

Funny thing is, in 1993, Doom tended not to be in stores. The SW episode was generally found on a BBS or a magazine disk and the full version was ordered direct.

The shareware version had a boxed version IIRC.

Share this post


Link to post

FOOLS! The point of leaving the keyboard and mouse operational in the Demo loops is to TORTURE the little Chill-rens that try and play the game with their grubby little hands. Finding the game INACCESSABLE, the unplayable game taunts them more and more until they complain and WHINE to their mothers to buy the ULTIMATE Glory that is DOOM2.

Share this post


Link to post
LogicDeLuxe said:

Does MAP01 and doom2.wad mean anything to you?

Yes. It means that I wasn't paying attention. ;)

Share this post


Link to post

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×