ScreenRecording into a movie file.

[Rackle]

Here are some Gamasutra links that may provide useful ideas/gotchas when trying to create video from saved game information:

Developing Your Own Replay System
Instant Replay : Building a Game Engine with Reproducible Behavior

And some other uses of that saved game information:

Better Game Design Through Cutscenes The paragraph titled Reward mentions replaying "great" moves by the player, which can raise the addiction of the player; they'll try to execute these "great" moves in order to receive the reward of seeing themselves in a movie.

The Full Spectrum Warrior Camera System The paragraph titled Gameplay Recording And Playback mentions replaying the scene but allowing the player to change the camera position/angle. This seems quite interesting when reviewing a failed attack (think Counter-Strike).

[bain]

Our game will be OSS and content CC-BY-NC-SA : http://creativecommons.org/licenses/by-nc-sa/2.5/

Although we have not started coding anything we are very much into preprod. The advantage of our "movie" system is the game is an adventure game so the scenes are set with static camera angles. so moving camera at a later stage becomes difficult.

We are actually meeting this weekend to discuss some specs on the system. Once they are done I'll post the specs and once we have code that as well

H

[Falagard]

Ya, I've created an offline movie recorder for a different engine in the past. As someone else mentioned, the basic idea is to create keyframes for your camera and object positions while playing the game in realtime, and save them out. Then, re-run your game in a special mode that reads those values and sets the camera and object positions each keyframe, interpolating between keyframes, with the render system updating at a fixed time step.

This means that although your game might only run at 15 fps with all the settings turned way up, (anti-aliasing, shaders etc.) you can step the updates at whatever frequency you want, so that when the images are assembled into a video in something like Adobe Premier it looks like it's running at 30 fps or whatever you want.

The interesting thing about Ogre is that you could potentially store the values of every object that Ogre knows about, such as entities, animations, particle systems, etc. as well as other systems such as CEGUI or the overlay systems and record all of their states into a file and have a generic system that will pretty much work with almost anyone's game.

Interesting thought.

[FrameFever]

http://www.farb-rausch.de/~fg/kkapture/
thats is a good tool for that purpose