How to edit a tileset?

[temnix]

I want to edit the overlay of an area. There is a room I want to redraw. Then I'd like to put the changed area back into the game-recognizable format. How do I do that? Near Infinity makes it possible to export overlays (TIS files) as PNG, but an "Unknown error" appears when trying to convert them back into MOS. Plus, I've managed to change the look of an area once, converted the file (I don't remember how), and the area ended up missing one tile, like a gap tooth, with just a black square there. It might have been a tile with a hidden door. What's going on there?

I would look into tutorials for this, but links to them from a few years ago are all non-functional.

[Jarno Mikkola]

You are confusing the tileset with the .are file properties, and it's connected tissues, aka other files. There's the tileset like said, arxxxx.tis or packaged tileset a arxxxx.tiz, then there's the arxxxx.are -file, the arxxxx.mos, the pictures or daytimelightmap arxxxxlm.bmp and nightlightmap arxxxxnl.bmp and travel area(or "high map") arxxxxht.bmp , and arxxxxsr.bmp, what ever that is.

[Angel]

Here's a working ling to a tutorial.  A bit dated as it doesn't tell about pvrz files, but most is still correct.
http://www.simpilot.net/~sc/dltcep/index.htm

Basically, you have to convert the tileset to a bitmap, edit it with a normal image editor like PhotoShop or GIMP, then convert the edited bitmap back to a tileset.  After that you may have to change or add polygons, depending on what exactly you edited.

[temnix]

@Angel Thanks for the link. Hopefully PVRZ won't be too different, because this mod will be for the EE engine. The area is a dungeon, it has no daytime-nighttime specials, and I only want to redraw a patch of the floor.

[temnix]

Okay, the tutorial was of no use. DLTCEP is too different from Near Infinity, and anyway I suspect it's not about the right stuff. What I want to do is: export an area's ovelay to PNG, redraw a portion of it in an editor without changes to the number and position of tiles, lightmaps or anything else - a looks-only change, then convert the whole to PVRZ, because I assume that's how it's done. There are converters for this in Near Infinity, but the program gives me an error at this step, "Unknown error," in fact. Is that anything familiar to anybody?

[DavidW]

Do it at the TIS level, not the PVRZ. In NI: export TIS to PNG, edit the PNG in photoshop, re-import to TIS. 

[temnix]

@DavidW I did it, and when I put the PVRZ files that resulted in override, the area showed the change - only the tiles were a-jumble, all over the place! This gave me a great idea about a level challenge, but still, the proper arrangement takes some file with instructions about putting the tiles together.

[DavidW]

Did you put the tis file that resulted in override too?

[temnix]

@DavidWNo, I didn't notice that one. Should be okay now. Thank you. By the way, do you know if it's possible to copy a file over into override while playing? The TIS file. Would that change presentation of an area already in the GAM file?

Edited June 5, 2020 by temnix

[DavidW]

GAM contains no area data: it stores party members, globals, and a bit more non-area-specific data. Area data lives in SAV, but that only stores the ARE files, hence only the references to the TIS and WED files, not those files themselves. (In accordance with the principle that it would be silly to put anything immutable into the savegame.)