Is there any way to prevent people from making my web game available offline?

It's not the type of game that really need a server to operate. I'm using javascript and html5 right now, and I cant think of a way to prevent the game from being ri开发者_JS百科p off.

Using obsfucator is useless, the game would still work offline.

Implementing a validation scheme is not invincible either. Someone smart can just crack the script and remove the validation part.

Make it attractive for users to play on your site.

For example:

• Provide online Highscores.
• Introduce a multiplayer option
• Create friends list
• Provide a server based achievement system
• Develop other games and provide them on the same page so users want to come back
• Create "level packs" and similar add on content and release them on your page

Overall, there are other possibilities to get users to play on your site besides technical restrictions, which - as you already found out - are difficult to deploy in an open source, browser driven environment. But, on the web, this has always been a feature, not a bug.

You're right in that a clientside-only can't be prevented from running offline. How about moving part of the game logic to the server?

You could continue to use html5 and javascript, but move your javascript to the server side using node.js For example http://www.yuiblog.com/blog/2010/09/29/video-glass-node/

If you combine obfuscation and validation, you'll go a long way. Can someone crack and use it offline? Possibly. Is it really going to be worth the effort? I mean, even an installed game can be cracked. This is especially true if you make the validation extra obfuscated by hand by spreading it out over several methods.

I would avoid moving more logic to the server than you have to, because it would obviously slow the app way down, but you might be able to get away with moving tiny crucial pieces that only happen rarely like between levels (chapters?).