   replays and video econding
  I have a completely deterministic game (using SDL for video and SDL Mixer for audio). I want to add the ability to create replays, and then turn the replays into videos.What is the best way to go about this? I'm not sure where to start.I know that I can save a screen capture of each frame in SDL with SaveBMP, but I have no idea what to do about audio, or how to make sure the audio remains in sync with the video. Furthermore, I don't know how to turn a series of bitmaps into a high quality video. My game runs at 62.5 fps, but I think videos normally run at a lower fps, so I guess I'll have to interpolate between frames or blur them together or something. But at 30fps, this is likely to produce aliasing effects.   
  Does anyone have any advice? Surely someone has done something like this before.   ;  I have not done this before, but I don't think it is efficient to save every single frame !You could rather store for each frame the objects positions and/or user inputs, so that you can reconstruct the sequence.   ;  Do you use floats or doubles in your game logic?   ;  I use doubles, but the physics engine (Box2d) uses floats internally. I'm not sure why that matters though.The user input consists of just a couple of booleans each frame.   ;  So does anyone have any actual answers to my questions?   ;Quote:Original post by StoryyellerI use doubles, but the physics engine (Box2d) uses floats internally. I'm not sure why that matters though.Depending on the computer architecture, floating point computations are not always deterministic. That's why Java has the strictfp keyword, for example.;  Can that be changed with compiler switches? I'm using gcc.   