"Collaborative" Canvas Designer i.e. Canvas-Drawing tool allows you draw bezier/quadratic curves, rectangles, circles and lines. You can also set strokes, back/forth colors and much more. You can draw using pencils, erase drawing, type texts etc.

This speciality of this drawing-tool is that, it generates Canvas2D code for you; so simply draw and get the code!

Also, you can collaborate your drawing with up to 15 users; and everything is synced from all users. So, if you draw a line and your friend-A draws quadratic curve and friend-B draws rectangle then everything will be synced among all users!

1. Take all code from this link and upload somewhere on your site.
2. Target directly will be having this file: canvas-designer-widget.js. Link this file in your HTML/PHP page.
3. Use this command to append widget in your HTML page:
   

       <code>CanvasDesigner.appendTo(document.documentElement);</code>
   </li>
   

websocket.onmessage = function(event) {
    CanvasDesigner.syncData( JSON.parse(event.data) );
};

CanvasDesigner.addSyncListener(function(data) {
    websocket.send(JSON.stringify(data));
});

CanvasDesigner.setSelected('pencil');

CanvasDesigner.setTools({
    pencil: true,
    text: true
});

CanvasDesigner.appendTo(document.documentElement);

It is having CanvasDesigner.destroy() method as well.

webrtc.onmessage = function(event) {
    CanvasDesigner.syncData( event.data );
};

CanvasDesigner.addSyncListener(function(data) {
    webrtc.send(data);
});

socket.on('message', function(data) {
    CanvasDesigner.syncData( data );
});

CanvasDesigner.addSyncListener(function(data) {
    socket.emit('message', data);
});

1. https://www.webrtc-experiment.com/Canvas-Designer/
2. https://github.com/muaz-khan/Canvas-Designer
3. https://canvas-designer.appspot.com/

Original source-code was shared 2-years back, here: https://github.com/muaz-khan/Everything/tree/gh-pages/Canvas/Tools/Designer

There is a similar "tinny" tool, however it isn't yet supporting collaboration: https://canvature.appspot.com/

And WebRTC-Experiments! https://github.com/muaz-khan/WebRTC-Experiment

Canvas Designer is released under MIT licence . Copyright (c) Muaz Khan.