I made a simple demo to show what I mean. My FPS on my machine is around 180, but the ball is still very fuzzy as it moves around.
It's in a zip file, with an executable here:
Any ideas what to do? Or should I switch to openGl/directx
If you set up SDL to use an OpenGL context you can use a wrapper like hxRender to convert all of the blits to OpenGL and not have to convert the rest of your sound-handling, graphics loading, etc. from SDL to something else as you switch platforms from one to the next.
maybe you should use double buffering to get more stable movement.