Persistent Whiteboard with node.js and websocket | Hacker News Reader

Persistent Whiteboard with node.js and websocket

draw.2x.io

29 pointseinaros14 comments

It's interesting opening two tabs and only drawing on one, and using the second tab to see what other people are probably seeing.

Some strokes have huge lag during spikes, others that I made on my screen are never displayed on the other tab.

The server had a hard time dealing with the load. I suspect running node.js on Cygwin contributes negatively in that regard. Furthermore, my custom serverside canvas could probably benefit from being asynchronous, and the server really should batch up updates within a certain time frame, to not hammer other clients.

Neat! Though, on Ubuntu with Chrome 9.0.597.98 I never got loaded after 2 minutes. This could just be due to traffic load though. However, I was able to see other people scribbling, which was still fun.

The server is being hammered pretty hard at the moment. It's taken on 30-40 simultaneous users before, and worked without a glitch. Now it's around 50, and a few seem to be going beyond the normal update rate.

At some point I will have to enforce a harder rate limit, and/or build better spam protection. The app has been pretty much unused for the last 5 months though, so there hasn't been any real reason to focus on that part :)

I have FF4.0b11/MacOS ("Firefox is up to date") and it gives me the "requires... FireFox 4+ (available from the beta site)" message.

Sorry about that. FF has websocket support disabled for now, and I've been slow to move to socket.io. That, and plenty other updates, are in the works. :)

Thanks to whoever wrote "skillz" next to my portrait of pg :)

And nice app, it would benefit from a little chat box though.

Haha that was me, np ;-) Shame some low-life scribbled over it.

A chat box would be nice, yeah!

This is fun, but you should remove the eraser. I think you'd find more creative graffiti without it.

Duely noted. For the next version of the public board I'll do that!

An ever expanding space would be neat too. No need for an eraser, just find some blank space to write on.

Does this maintain a canvas on the server?

Yes. Custom implementation I never updated beyond the very basics. There has since been released a better node.js canvas by LearnBoost.

Love it.

Reply on news.ycombinator.com