hello, I'm learning to make 2d games and so far I'm able to make them work. But I need help editing my sprites (2d images) I download "the GIMP", but I need to add an alpha channel to "BMP" format, but the gimp doesn't allow such a thing and the game design book I have says that it should be allow.
I also need to make the formats: BMP, DDS, DIB, JPG, PNG, and TGA. To allow animated sprites. (layer over layer) I can't do that in the GIMP.
something like this, but on BMP format or any other of the above formats.
anyone has an idea of what i can do to accomplish this? (I don't have money for adobe photoshop)