Doom 1.1 looking weird as all to heck

[LittleInferno]

I'm running MS-DOS 7.10 in VirtualBox. The virtual machine has 65MB of base memory and 9 MB of video memory if that'll help.

http://imgur.com/a/lPY19

[Linguica]

Hahaah baller, make a video

[LittleInferno]

Here ya go.

https://www.youtube.com/watch?v=Rfgc47mup7c&feature=youtu.be

[VGA]

Virtualbox emulates the OS perfectly but not the hardware needed for the old games to work properly. That's why Dosbox is the best DOS emulator, it emulates at throttled CPU rate, the popular S3 Virge card, a Soundblaster soundcard etc.

[RUSH]

It's like the LSD: Dream Emulator version of Doom.

[LittleInferno]

Good thing I use DOSBox frequently. Heretic works fine strangely.

[Quasar]

LittleInferno said:

Good thing I use DOSBox frequently. Heretic works fine strangely.

That would suggest it's something to do with the way Doom uses VGA tweaking.

Heretic and Hexen run in plain jane linear Mode 13h. Doom and Strife however run in a tweaked variant called Mode Y, which turns unchained memory back on, allowing for 4 pages worth of flipping space.

Does Strife have the same issue? I would expect it.

[Memfis]

Awesome, I want to play it!

[LittleInferno]

Strife didn't take 5 pounds of LSD like Doom did. It worked the same as Heretic.

[VGamingJunkie]

Almost a shame there isn't a way to do this on purpose, I imagine it could be used to pretty cool effect.

[fraggle]

Looks like the column/span drawing functions used to draw the walls/floors+ceilings are screwed up, drawing things at the wrong scale. Notice how the geometry itself looks fine, it's just the textures that are messed up. Interesting glitch.

[Quasar]

fraggle said:

Looks like the column/span drawing functions used to draw the walls/floors+ceilings are screwed up, drawing things at the wrong scale. Notice how the geometry itself looks fine, it's just the textures that are messed up. Interesting glitch.

Maybe it doesn't like the self-modifying code version of R_DrawColumn? That would not explain problems with spans, however. I would like to know if Strife has the same issue, and if Hexen does not, as that would solidify my theory about the Mode 13h vs Mode Y distinction.

[joe-ilya]

Does it mess up the sounds?

[LittleInferno]

Woops, I accidentally used DOSBox for Strife instead of VirtualBox. I'm a dummy.

[LittleInferno]

Well, Strife won't even go to the menu because "ClearTmp: Couldn't open dir strfsav6.ssg". :p

[fraggle]

Quasar said:

Maybe it doesn't like the self-modifying code version of R_DrawColumn? That would not explain problems with spans, however. I would like to know if Strife has the same issue, and if Hexen does not, as that would solidify my theory about the Mode 13h vs Mode Y distinction.

Is it really self-modifying? I guess that part is another thing that was lost in the source distribution?

[VGA]

@LittleInferno
You can try FreeDOS, too. Would be interesting if it's the same or not.

[FireFish]

LittleInferno, did you already experiment with the doom setup program to change its video modes, especially to the Vesa one ?

VGA said:

@LittleInferno
You can try FreeDOS, too. Would be interesting if it's the same or not.

It should not be, to my knowledge doom runs fine on FreeDos.

[Never_Again]

FireFish said:

LittleInferno, did you already experiment with the doom setup program to change its video modes, especially to the Vesa one ?

I sense some wires crossed somewhere. ;)

[Quasar]

fraggle said:

Is it really self-modifying? I guess that part is another thing that was lost in the source distribution?

Yes; They were implemented in the tmap.S module. Strife still uses that code so I've seen it in its linked form. I could extract it some time and try to pretty it up if I ever have time.

[Quasar]

LittleInferno said:

Well, Strife won't even go to the menu because "ClearTmp: Couldn't open dir strfsav6.ssg". :p

Try properly installing the game, or at least getting a complete version of it from wherever *cough* you are getting it; because the directories strfsav0.ssg through strfsav6.ssg *must* exist and are normally created by installing the game. The game executable itself *will not* create them.