W3C home > Mailing lists > Public > public-html@w3.org > February 2012

Re: ISSUE-201: Change proposal

From: Ian Hickson <ian@hixie.ch>
Date: Fri, 10 Feb 2012 19:12:22 +0000 (UTC)
To: Frank Olivier <Frank.Olivier@microsoft.com>
cc: "public-html@w3.org" <public-html@w3.org>
Message-ID: <Pine.LNX.4.64.1202101901280.13116@ps20323.dreamhostps.com>
On Fri, 10 Feb 2012, Frank Olivier wrote:
> I would like to submit http://www.w3.org/wiki/Canvas_hit_testing as a 
> change proposal for this issue.
> This proposal adds a method for authors to link bitmap regions (paths) 
> on a canvas element to canvas subdom elements, enabling simpler hit 
> testing and better coding patterns for canvas user interfaces. User 
> agents can use the region boundaries and element properties to provide 
> accessible user experiences.

FWIW, it's my intent to add the feature described in this change proposal 
as part of the Path primitives feature which is the next on the list of 
things to add to canvas. I think it would be a mistake to address this in 
a piecemeal fashion rather than looking at all the current limitations of 
canvas at once and addressing them together to the extent that it makes 

(Example of things that might be better than setElementPath() would be, 
for example, making stroke() and fill() for Path primitives take an 
optional Element; having touch UIs that describe onscreen controls while 
the finger is dragging around explicitly be told by the spec to call out 
widget boundaries by doing edge-detection on the paths painted so far; 
having hit detection be integrated with the same mechanism so that authors 
are more likely to use it; having clearRect() integrated with the same 
mechanism so that authors are more likely to not forget to clear the 
element assocations; etc.)

Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'
Received on Friday, 10 February 2012 19:12:45 UTC

This archive was generated by hypermail 2.4.0 : Saturday, 9 October 2021 18:45:48 UTC