Install dependencies,

$ npm i

Start the dev server,

    Rect: [
      params.x,
      params.y,
      params.x + params.width,
      params.y - params.height,
    ],

$ npm start

Build documentation,

$ npm run docs:build

Run test,

$ npm test

Build library via father,

$ npm run build

注意 lower-canvas --> canvas1 upper-canvas --> canvas