When i move sdl window the app freeze...

[arthurprs]

Well my main loop contains no readln or anything, it just displays the graphics over and over again. It doesn't pause or anything... yet.

So try to manage events at begin of main loop

//declare
event: TSDL_Event; // sdl event

procedure Manageinput;
begin
  while SDL_PollEvent(@event) > 0 do
       if event.type_ = SDL_QUITEV then
          dosomething;
    end;
end;

and also add

SDL_Delay(35);

to end of main loop