Tilesets can modify how the game looks entirely, yet are easier to make than full blown factions. In terms of difficulty, they lie between maps and factions. Tilesets consist of models and textures for the objects, textures for the surfaces, sound files for the ambiance and day/night starting sounds, and a single XML file that defines the tileset. Because of this, you will require the ability to create models and textures, as well as a basic understanding of XMLs.
- See Tileset XML
Surfaces are merely 2D images that are tiled repetitively over the map. You can set frequency rates for these so that if you use multiple surfaces, the "uncommon" changes (such as a noticeable rock) appear less frequently than the "plain" textures. These textures should be BMPs or TGAs to ensure support on all engines, though PNG is supported by both MegaGlest and GAE, as well as JPG is supported by MegaGlest and soon to be support by GAE.
Tilesets use the same standard G3D models as factions do. Thus, Blender is the main tool used to create 3D models. The models for objects are then defined in the XML. You can have multiple models for one object, as you can have child tags inside the object containing different models. This is highly recommended for trees, as it adds variety. If the trees are all the exact same model, the tileset ends up becoming very repetitive. The walkability for models, which defines whether or not units can walk through that object, should be constant between all tilesets, so as to prevent your tileset from breaking maps.
Sounds can be either OGG or WAV files. The ambiance sounds are the long, looped sounds that make up background noise, such as birds chirping, etc. The day and night starting sounds are played once when the day or night initially starts.