Difference between Boom fromat and Doom2 format map

[Yousuf Anik]

I want to know what are the actual differences between Boom format and Doom2 format map. What problems will I get if I make huge slaughter maps in Doom2 format?? Suppose a megawad of slaughter maps in Doom2 format!! Can anyone please explain in details?

[Ribbiks]

most notably:

boom format gets you generalized linedefs, voodoo doll trickery, and all sorts of cool effects: https://www.doomworld.com/vb/source-ports/84681-interactive-boomref-txt/

the ones most authors use for visuals are:

- sky transfers (action 27...1? 271?, sure), turn the sky of the map into any texture you want
- action 242, fake ceiling and floor heights. bloody invaluable.
- scrolling floors, conveyor belts, etc..
- silent teleports

in general boom features are a superset of doom features, with some wrinkles to keep in mind:

- in boom you can lower sectors with monsters "stuck" in them, iirc you can't do this in doom
- monsters get pushed off ledges in boom, not in doom. this can be annoying to map around, cue a spooky theremin and a screenshot of sunder map05

[Cynical]

Sky transfers aren't actually Boom format. They're an MBF feature that prboom-plus inaccurately supports at cl 9.

[Ribbiks]

nitpicky, but correct. At this point I've just internalized "boom-compatible" to mean prb+ cl9 or equivalent, possibly to the displeasure of the players out there who load up the actual exe on dosbox.. either way sky transfers are nearly ubiquitous among wads calling themselves boom-compat nowadays.

[Gez]

Stuff such as sector and sidedef references are unsigned (with 65535 meaning "none") instead of signed (with -1 meaning "none"). This allows larger, more complex maps than Doom could otherwise support.

There are no real differences in the format otherwise. Boom does have a greater list of linedef and sector types, but I don't consider that to be a change in the format.

[vita]

Boom adds flags 0x0020 (not in DM) and 0x0040 (not in co-op) for things. And because PrBoom+ has sky transfers in cl9, MBF adds flag 0x0080 (friendly).

Edit: also, read this (it's more about compatibility, though).

[Memfis]

When this MBF stuff was first discovered, entryway actually disabled sky transfers in -complevel 9. And then people freaked out.

[printz]

How come nobody has mentioned winds and currents? Those are very useful to make areas more challenging!

[Memfis]

Last I've heard they have different strength depending on the port you're playing with, so using them effectively is tricky. Or maybe it's not a problem anymore?

[Yousuf Anik]

Wow, a world has just opened for me! Many many thanks to you guys for replying and the explanations :) btw, what are wind, friction and currents? How do I make them work?? Any demo map or example?

[printz]

Hint: in addition to the wind, current and friction trigger linedef types (which will be activated at map startup, not when you step on them), you must also set the target sector generalized properties (look for a "generalized" button, tab or label in the sector property dialog box).

Memfis said:

Last I've heard they have different strength depending on the port you're playing with, so using them effectively is tricky. Or maybe it's not a problem anymore?

God damn, I hope it's not ZDoom which breaks them.

(However I know that MBF broke the point push/pull behavior by changing it to affect monsters without user opt-out, and Eternity carried that on — but that doesn't affect sector winds and the others).

[kb1]

printz said:

(However I know that MBF broke the point push/pull behavior by changing it to affect monsters without user opt-out, and Eternity carried that on — but that doesn't affect sector winds and the others).

Boom's implementation was extremely slow and problematic - that's why monsters were not allowed to be affected in Boom - the game would crawl. MBF did an optimal implementation, so it was possible to allow everything to be affected.

But, for gameplay reasons, I guess having an option would have been nice...?

[Graf Zahl]

kb1 said:

Boom's implementation was extremely slow and problematic - that's why monsters were not allowed to be affected in Boom - the game would crawl. MBF did an optimal implementation, so it was possible to allow everything to be affected.

Aren't you mixing that up with the friction implementation - which was indeed horrendous in Boom.

But the pushers/pullers don't really do that much - only adding some momentum to all affected players and/or monsters, so it doesn't really matter that much, if it adds something to 1 or 10, it'd have to check each single one anyway.

The not being able to opt out part was just stupid, though.

[kb1]

Graf Zahl said:

Aren't you mixing that up with the friction implementation - which was indeed horrendous in Boom.

But the pushers/pullers don't really do that much - only adding some momentum to all affected players and/or monsters, so it doesn't really matter that much, if it adds something to 1 or 10, it'd have to check each single one anyway.

The not being able to opt out part was just stupid, though.

Oops, I think you are correct - old age, you know? :)