Might Sound Like a Noob Here...

[Elaxter]

What is an .imp file? I know that it is used to record FDAs, but what is it? More importantly, how do I open one?

[IMX]

.lmp files are generally Demo files (when being posted here as FDAs) that can be opened with PrBoom+ (along with the necessary ~*~complevels~*~) to showcase playthroughs of maps and stuff.

[Elaxter]

IMX said:

.lmp files are generally Demo files (when being posted here as FDAs) that can be opened with PrBoom+ (along with the necessary ~*~complevels~*~) to showcase playthroughs of maps and stuff.

Oh oh oh! .Imp! I gotcha. That makes sense. Thanks

[fraggle]

No. .lmp. It's an abbreviation of "Lump".

[plums]

Actually if you use PrBoom+ you should not specify a complevel, in almost all cases it will autodetect correctly.

The easiest way to play back a demo is to control-click the .lmp and the wad it was made for (assuming it's not for doom2.wad or another iwad) and just drag them both onto prboom-plus.exe

If it's a ZDoom demo (or other advanced port demo) you need to drag it onto zdoom.exe and make sure you use the same version of the program that was used to record it. ZDoom 2.7.1 is the most popular version for recording demos these days, because it's the latest stable version. If someone records a ZDoom demo they will typically say so, otherwise assume PrBoom+ can do the job.

[Elaxter]

Now. How do I start recording my own demos in prboom? Zdoom?

[plums]

Elaxter said:

Now. How do I start recording my own demos in prboom? Zdoom?

Run the program with the right parameters. You can do this on the command-line, with a batch-file, using a launcher like ZDL or CDL, or maybe some other methods.

Here are the parameters you'll usually need:

-file [wadfile.wad] [otherfile.wad] which file(s) to load
-warp [map number] which map to warp to. In PrBoom+ you can omit the number and it will warp to the first map in the wadfile you're loading.
-complevel [number] for PrBoom+ only, which compatibility level to use. Usually this is 2 for doom2 vanilla/limit-removing maps, or 9 for Boom compatible maps. If you're unsure 9 will work for most things.
-record [demoname] filename of the demo to record.
-iwad [iwad] specify which game to use. Usually not needed if you're recording a doom2 map.
-skill [skill number 1-5] which skill to play on. If you don't specify it will use the default skill, which in PrBoom+ I think is 4 (ultra-violence) unless you change it, but most other ports is 3 (hurt me plenty). [edit: you caught me DoTW! ;)]

So for example to record a demo on MAP03 of a vanilla map called coolwad.wad, I would run prboom-plus.exe -complevel 2 -file coolwad.wad -warp 3 -record coolwad-03_plm-fda.lmp and end up with a demo called coolwad-03_plm-fda.lmp, which I can then post in the right thread for other people to watch.


For far more information about command-line parameters than you need, check these two links:
http://doomwiki.org/wiki/Parameter
http://doomwiki.org/wiki/Source_port_parameters

[Demon of the Well]

Be sure to specify the skill level with the -skill parameter, as well (-skill 4 = UV, -skill 3 = HMP, etc.), unless your program defaults to the skill level you want. I....actually have no idea what skill level the current PrBooM+ defaults to (maybe it has a memory function?), I don't think I've ever not entered the parameter when recording.

[4shockblast]

I believe the default in PrBoom+ is HMP, though you can change the default in the settings. Also, you don't need to write ".wad" after the files in PrBoom+ (or ".lmp" after the demo name).

[Enjay]

fraggle said:

No. .lmp. It's an abbreviation of "Lump".

Indeed. Most (perhaps all) items inside a WAD file are "lumps" and it isn't unusual for a WAD management program to export items as LMP files, regardless of type (graphic, sound, whatever) when exporting the data in its raw/native format.

However, the extension "LMP" is most commonly associated with demo files. I suspect that this is because the original Doom had the ability to record demos and, when it did, it saved them with the LMP extension. These were the only easily accessible files associated with Doom that had this extension and so, for many people, LMP became synonymous with "Demo".