High-definition Full-motion background system in XNA

Question

I'm mostly just working on this as a hobbyist thing, but here's my problem: I got a bit excited over finding the 'Video' and 'VideoPlayer' classes in XNA 4, and hoped to make a game that works a little bit like how Myst does - with very active backgrounds, but no actual 3D graphics. (Technically, Myst 1 had static backgrounds, but maybe you get the idea) I threw together a small test game in XNA, with a pretty simple WMV included.

The problem I have is that it's not quite responsive enough. I'd like my system to be able to swap the current video in a millisecond, so that the player could click a contraption in the background and instantly see it move. Right now, when I press my trigger key that calls this code:

    private void cycleVideos()
    {
        videoIndex++;
        if (videoIndex == videos.Count)
        {
            videoIndex = 0;
        }
        activeVideo = videos[videoIndex];

        vp.Stop(); // Couldn't find a 'Seek(0)' method
        vp.Play(activeVideo);

    }

...it takes about a full second to re-seek the position it needs, and start playing again. In this example, I hadn't even encoded my video to the HD (1920x1080) resolution I had been planning on. I can understand if XNA's video system is really only meant for full cutscenes between missions or that sort of thing; I'm willing to use additional memory to have large parts of my videos cached, or even include a bit of a dynamic caching system so that things are loaded/unloaded over time (after all, this is the main visual of the game), but I'd like to hear if I have any decent options to accomplish this.

I'm also somewhat open to the idea of using a different engine or coding environment entirely.

EDIT: I've been doing some experimentation in my eagerness to solve this. I can definitely get some faster responsiveness by avoiding the 'stop()' calls, and by maintaining multiple instances of VideoPlayer. A paused video will resume much more quickly; and it's possible to play(), then pause() a video immediately (at the beginning of the program, in order to 'cache' it). It's not a full solution yet - I want to be able to seek back to the beginning of a video, and I still feel like there should be some possibility of that somewhere.

Answer 1

To seek you should use the PlayPosition property of VideoPlayer (http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.media.videoplayer.playposition%28v=xnagamestudio.31%29.aspx)

I think the best way to do this, if you want quick turnaround time, it to cache the VideoPlayer instances.

Another idea would be just to cache the textures for x seconds, while the VideoPlayer reloads the new file, then switch over to take the textures from the loaded one. To expand on this idea: you can make a new class CachedVideo which will be a "lightweight" wrapper over Video and VideoPlayer. Here, you will implement the Update and Draw loops in a 'producer-consumer' pattern, using a circular buffer:

• Update takes a texture and puts it into the buffer
• Draw takes one texture and draws it.

To allow a period of pre-buffering, you could specify a certain time amount to execute just the Update loop before actually executing the Draw call. This way, even if you need to loop the video, you'll already have something like 3-5 seconds of pre-buffering.

One problem still arises here is that the initial pre-buffering still takes a while. You could mitigate it by letting some sort of load screen to be shown in the meantime.