Both in SDL1 and SDL2, when you create surfaces, you can specify the pixel format - when you create an RGB texture, you need to specify the R,G,B,A-masks. You can have RGBA, ABGR or whatever you really want (although with some pixel formats, SDL's "draw line" / "fill rect" functions seem buggy and may draw a blue rectangle instead of a red one). So I guess you could try creating a Tilengine-compatible surface that way.