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Show HN: A virtual whiteboard for working or teaching remotely

whiteboardfox.com

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Re: Show HN: A virtual whiteboard for working or teaching remotely

#101

Post by henningo »

MarkMc wrote: post #10
rhubarbcustard wrote: post #7

Earlier quoted context omitted.

Nicely done, website is nice and it's great that you can just click and get started straight away. In your comment you said you moved away from mySQL, what exactly do you store in the DB? Which leads to the question: how do you transfer the drawing data between clients? I guess it's not a case of uploading a Canvas as an image?

The drawing is basically a list of strokes, and a stroke is a list of points - that is, (x, y) coordinates. So the database is mostly a huge table of (x,y) coordinates. Uploading the entire canvas would far too inefficient - I simply upload the points. The transfer between two clients uses a technique called 'long polling'. That is, the client sends an HTTP request to the server, and the server doesn't respond until…

Did you consider doing spline fits to the x,y coordinates and then just saving the spline coefficients instead?

The fit process could likely be done client-side, and could offer some subtle smoothing if wanted?

Anyhow, really nice execution!

Re: Show HN: A virtual whiteboard for working or teaching remotely

#102

Post by cpncrunch »

jasonkester wrote: post #45

Nice first cut. It's actually surprising that it took a full seven years for anybody else to show up Twiddla's [1] space with a true HTML5 whiteboard. Back when we started out, there were half a dozen commercial versions of this exact thing, but all in Flash or Java, and all trying to compete with WebEx. It think you're on the right path positioning this for use in schools. That's our main use case too, replacing ove…

It was more like two years actually :)

Anyway, back in 2007 java and flash were reasonable solutions. Today, not so much.

PS, how do you make any money from twiddla if you give away free educational accounts?

Re: Show HN: A virtual whiteboard for working or teaching remotely

#104

Post by bostonpete »

MarkMc wrote: post #2

This is little 'scratch-your-own-itch' project I started working on about 9 months ago. Front end is GWT, back end is Java servlets. Database was originally MySQL but switched to Prevayler for performance reasons. My YouTube video gives a nice overview of the benefits of a virtual whiteboard: http://youtu.be/MDEHFHG1l3Y What does Hacker News think?

One feature that would make this a killer app in my mind is the ability to import a photo of a whiteboard and have the virtual whiteboard reconstruct what was on the whiteboard in the future.

We often take a picture of the whiteboard at the end of the discussion -- being able to continue to edit that whiteboard at some point in the future would be very handy.

Re: Show HN: A virtual whiteboard for working or teaching remotely

#105

Post by nfmangano »

EngVagabond wrote: post #95
sidcool wrote: post #93

Very impressed Mark. Nicely done. Do you mind telling the technology stack?

He has commented below that the 'front end is GWT, back end is Java servlets. Database was originally MySQL but switched to Prevayler for performance reasons.' I have built a similar tool that is also an HTML5 / Canvas collaborative drawing app which uses Google Drive for storage and has no server code beyond that. It works offline (and syncs up with collaborators when you come online) and runs in Chrome, Firefox, Sa…

Building your solution to work without server code is amazing. Also, nice UI.

Re: Show HN: A virtual whiteboard for working or teaching remotely

#108

Post by ul5255 »

leetreveil wrote: post #58
MarkMc wrote: post #2

This is little 'scratch-your-own-itch' project I started working on about 9 months ago. Front end is GWT, back end is Java servlets. Database was originally MySQL but switched to Prevayler for performance reasons. My YouTube video gives a nice overview of the benefits of a virtual whiteboard: http://youtu.be/MDEHFHG1l3Y What does Hacker News think?

The video shows Mark explaining to Sally how a Facebook login would work on her website with the whiteboard. A killer missing feature seems to be microphone support, which the video alludes to.

Looking at all the feature requests here I can't help but think that you guys are reinventing TeamSpeak. The only difference I see is that with TeamSpeak you first must install a client whereas this runs in a browser.

Re: Show HN: A virtual whiteboard for working or teaching remotely

#109

Post by cpncrunch »

ArcticCelt wrote: post #61
mandor wrote: post #48

Earlier quoted context omitted.

I fully agree, especially for the text (it is hard to write with a mouse!). In addition, basic shapes like line/rectangle/circle would be welcomed (I am terrible at drawing a circle with a mouse).

I got the exact same feeling after using it for 2 seconds. Then watched his video demo and understood why he did it that way. He did the product with tablet users in mind.

You can probably use a wacom tablet instead of a mouse. It makes it a lot easier to draw freehand.

Re: Show HN: A virtual whiteboard for working or teaching remotely

#110

Post by jmeistrich »

EngVagabond wrote: post #94
MarkMc wrote: post #2

This is little 'scratch-your-own-itch' project I started working on about 9 months ago. Front end is GWT, back end is Java servlets. Database was originally MySQL but switched to Prevayler for performance reasons. My YouTube video gives a nice overview of the benefits of a virtual whiteboard: http://youtu.be/MDEHFHG1l3Y What does Hacker News think?

This is another HTML5 / Canvas collaborative drawing app that I built which uses Google Drive for storage and thus runs completely locally. Works offline and runs in Chrome, Firefox, Safari, iOS, and Android and supports touch. http://thesavior.github.io/draw/

Cool, feels as fast as a native app on my iPad. I like the infinite zooming and panning.
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