Just to chime in, my 3D engine uses TGA to import textures too because the code is dead simple. Sometimes when you are going to use your own format for saving

Just to chime in, my 3D engine uses TGA to import textures too because the code is dead simple. Sometimes when you are going to use your own format for saving data you could pick the simplest format for your import to accelerate productivity at the cost of diskspace. In a similar way I use collada for character animations, it gets alot of slack from AAA studios (who all use FBX) but for indie development it's simple enough to be able to implement in a reasonable time (XML so you can see what's what)... In the same line of thinking, I import static meshes from .obj, sound from .wav and last but not least font from .ttf! The limiting factor usually is the editor you use to create/manipulate the assets in the first place, always look to the simplest export format they have, for Photoshop TGA is the simplest! I export everything to my own custom binary formats to be loaded by the engine by customers, and there lz4 is a pretty good/simple RLE compression (RLE is also used by TGA BTW) and then .zip (also very simple!) to wrap it all up... Keep it simple!