- The .CTY files are used only when creating a new scenario, or when loading a scenario for editing. The game save file actually contains a copy of all of the info in these files, and it overrides whatever is set up locally when loaded.
- .CTY files specify the internal name of the cargo. RT3 maps that name through a hardcoded table to a message code in RT3.lng, or passes it straight through if there is no match.
- It's possible to change the name of a cargo in memory, and this will get saved and restored with the rest of the scenario. The economic displays, station cargo listings, and the warehouse recipes all show the new name of the cargo; however, existing buildings currently still display the old name.
- Icons are retrieved by taking the cargo's internal name, tacking on ".imb", reading that file, and then loading whatever 32x32 image it points to. If the name does not resolve to an .IMB, it uses the 'Any Cargo' icon.
The Challenge:
I'm still figuring out the logistics of how to change cargo specs within a scenario, but one piece is quite clear: we'll want to include as many new cargo icons as we can in the final 1.06. These should be 32x32 images, in whatever format you can create, with a black or transparent background and a look+feel that matches the other cargo icons. So, if there's a cargo you've always wanted to use in a scenario, bring up Paint, draw a picture, and upload your masterwork!
Make sure you're OK with having your work released under the Apache 2.0 license. Oh, and please mention what you've uploaded in this thread, so that the modding team can find it.