Support

License

jCanvas is licensed under the MIT license, which you can read on GitHub.

Frequently Asked Questions

• Does jCanvas support layers?

  • Yes, jCanvas supports layers through the Layers API.

• Does jCanvas support animations?

  • Yes, jCanvas supports layer animations through the Layers API. If you know how to animate using jQuery, animating layers works much the same.

• Does jCanvas support events?

  • Yes, jCanvas supports mouse events through the Event API. All standard mouse events are supported, including (but not limited to) click, mouseover, mouseout, and mouseup.

• Does jCanvas support drag-and-drop?

  • Yes, jCanvas supports drag-and-drop events through the Layer API.

• Does jCanvas support touch events?

  • Yes, jCanvas supports touch events through the Events API. Supported events include touchstart, touchend, and touchmove.

• Does Internet Explorer support jCanvas?

  • Unfortunately, Internet Explorer (versions 8 and earlier) do not support the canvas element, and therefore do not support jCanvas natively.
  • However, some users have had succes using jCanvas with a plugin called FlashCanvas, which emulates the HTML5 canvas on older versions of Internet Explorer.

• Why are my jCanvas shapes mispositioned?

  • By default, jCanvas considers a shape's center at its (x, y) position. You can change this behavior using the fromCenter property, which will measure a shape's (x, y) from its top-left corner.
  • For consistency, the same ideology applies when cropping an image, which also can be reverted using the cropFromCenter property.

• Why are my jCanvas images drawn after everything else?

  • Just as with any image, images drawn with jCanvas need to be downloaded by the web browser. This means that they will only be drawn on the canvas when they are fully-downloaded. To work around this, see the On Image Load section of the documentation.
  • Also note that images does not apply to jCanvas layers. That is, images that are jCanvas layers will always load before successive layers are drawn

• What's the difference between defaults and preferences?

  • In short, jCanvas defaults typically remain unchanged, while jCanvas preferences are meant to be changed and reset. Other than that, they start out with the same set of properties and values.

Bug Reports

If you are experiencing an issue with jCanvas, try updating jCanvas to the latest version before emailing me.

If you are emailing me about a jCanvas bug, please include the following information:

• The version of jCanvas you used
• A complete code example that reproduces the problem
• What you expected to happen
• What happened instead

Remember, the more you tell me, the more I can help. ;)

Contributing

If you have any questions or need to submit any bugs regarding jCanvas, you can:

• Email me
• Message me on Twitter (@caleb531)
• Submit an issue on GitHub

If you wish to extend jCanvas with your own methods, you can learn to do so using the Plugin API.

The jCanvas source is always publicly available on GitHub for your convenience.

Contact

Feel free to contact me about anything jCanvas-related. If you have a question, please ensure it isn't already answered in the Documentation.

Caleb Evans jCanvas Creator Email me Twitter

Dave Smith jCanvas Developer Twitter