The best replacement for sfml is sdl.


The best alternatives to sfml are rated as following:
★★★★★  sdl
★★★★  allegro
★★  xna
★★  opengl
★★  glfw
★★  libgdx
★  sdl 2.0
★  cocos2d-x
★  glut
★  monogame
★  sdl2
★  clanlib
★  lwjgl
  directx

Your alternative for sfml is not listed? Suggest!
Speaking about sfml, one probably shouldn't forget about qt.

Other search terms related to sfml and their ratings are:

★★★★★ qt
★★★★★ box2d
opengl
You have in mind a companion for sfml and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of sfml in all years. Click on graph for more.
sfml
sdl
allegro