Also, AFAIK SDL is limited to software rendering which is definitely not ideal. I think we're at the point where most even integrated graphics chips will support oGL.
OpenGL is definitely supported by SDL. I saw people say SDL only supports software rendering in another thread too, but it's not true. It does support an OpenGL drawing mode. Though there are a couple downsides OpenGL in SDL, mainly that any time you resize the window or adjust the resolution, it nukes your GL context. You can get around this by not allowing windows to be resized, but it's not entirely ideal.
That said, I've been considering switching my engine to SMFL. It seems interesting, and I've read a little about it.