A game project usually consists of a large number of external assets that are produced in various specialized programs for producing graphics, 3D models, sound files, animations and so forth. Defold is built for a workflow where you work in your external tools and then import the assets into Defold as they are finalized. When the assets are imported into Defold they can be used by the various component types to create flipbook animations, tilemaps, particle effects and many other things:
Defold does not provide editing tools for creating images, sound files, models or animations. Such assets need to be created outside of Defold in specialized tools and imported into Defold. Defold automatically detects changes to any asset in the project hierarchy and updates the editor view accordingly.
There is currently no way to hook custom build steps into the in-editor builder, but we provide a stand-alone build pipeline (see Bob the builder) that can be incorporated in any pipeline.
The editor saves all Defold assets in text based files that are merge friendly. They are also easy to create and modify with simple scripts. See this forum thread for more information. Note though that we do not publish our file format details since they do change once in a while.
Extra care should be taken when working with Defold asset files through a text editor or external tool. If you introduce errors those can prevent the file from opening in the Defold editor.