node-wintab from https://github.com/meta-meta/node-wintab node-gyp rebuild --target=1.4.14 --arch=x64
todo:
http://labs.crosspop.in/Croquispop/croquispop.html
https://github.com/intridea/sketch.js
http://mrdoob.com/projects/harmony/#ribbon
http://www.w3school.com.cn/tags/canvas_globalcompositeoperation.asp
http://balefrost.org/programming/CanvasComposite/index.html http://stackoverflow.com/questions/22891827/how-do-i-hand-draw-on-canvas-with-javascript
curve: http://fabricjs.com/quadratic-curve projects: https://neocities.org/browse