Local web storing of files using HTML5

I was fascinated by Google Gears and its potential use in online game development, particularly massive online game development. One could take the game resources and store them locally using ResourceStore, thus reducing game load time, server bandwidth issues, etc. I have therefore welcomed the news that HTML5 supports offline storage.

However, from what I can tell it only supports a manifest file for resource caching, which looks like something ManagedResourceStore is supposed to offer. I didn't study either in detail.

I also didn't find somethi开发者_StackOverflow中文版ng that would allow programatically loading resources and caching them (as apparently ResourceStore allows).

Is it possible to programatically control which resources should be cached? Or would I have to store each "map" on a separate page with separate manifest file (with this being in fact done through a server side script, instead of literally creating pages and manifests -- this is still fugly)?

If you're asking about design work, it seems like you're looking for Programmable HTTP Caching and Serving. If you actually wanted to know if there's something like this in shipping browsers, then I don't know, but doubt it.