angular-canvas-painter

angular-canvas-painter

Angular.js directive to paint on a canvas on desktop or touch devices

View Demo

Usage

1. bower install angular-canvas-painter
2. Include dist/angular-canvas-painter(.min).js from bower_components/angular-canvas-painter/dist.
3. Add pw.canvas-painter as an angular module dependency.
4. Use the pw-canvas directive in your template to create the painting canvas.
5. Optionally you can use the pw-color-selector directive to choose colors from.

####pwCanvas

<div pw-canvas options="{width: 400, height: 300, color: '#ff0'}"></div>

Options

{
  width: 400, //px
  height: 300, //px
  backgroundColor: '#fff',
  color: '#000',
  lineWidth: 1, //px
  opacity: 0.9, //0-1
  undo: false // boolean or a number of versions to keep in memory
  imageSrc: 'images/example.jpg', // loads the specified image and sets it as background image,
  customCanvasId: 'myCustomId' // define a custom value for the id attribute of the canvas element (default: 'pwCanvasMain')
}

Undo

To enable the undo function set undo: true in the options and provide a version attribute:

<div pw-canvas options="{undo: true, width: 400, height: 300, color: '#ff0'}" version="model.version"></div>

The version attribute will always be set to the amount of available versions in memory. To undo a stroke just decrease the version number in your surrounding controller e.g. model.version = model.version - 1. To jump back 3 versions set model.version = model.version - 3.

You can set a maximum number of saved versions to prevent too much memory consumption by setting a number instead of true in the options, e.g. {undo: 20}

####pwColorSelector

<div pw-color-selector="['#000', '#00f', '#0f0', '#f00']" color="selectedColor"></div>

To use pwColorSelector with pwCanvas set the color option in pwCanvas to the color variable of the selecot:

<div pw-canvas options="{color: model.myColor}"></div>
<div pw-color-selector="['#000', '#00f', '#0f0', '#f00']" color="model.myColor"></div>

Drawing algorithm

The drawing algorithm to produce clear and smooth edges is based on a great article by Rishabh

License

MIT

Changelog

0.4.0 (2015-07-16)

Features

• new touch position calculation method - works now the same way for Android and iOS (#9 #2)