- From: David Singer <singer@apple.com>
- Date: Thu, 28 Jul 2011 17:04:34 -0700
- To: Charles Pritchard <chuck@jumis.com>
- Cc: Richard Schwerdtfeger <schwer@us.ibm.com>, Canvas <public-canvas-api@w3.org>, Frank Olivier <Frank.Olivier@microsoft.com>, paniz alipour <alipourpaniz@gmail.com>, Cynthia Shelly <cyns@microsoft.com>, Steve Faulkner <faulkner.steve@gmail.com>
On Jul 28, 2011, at 16:48 , Charles Pritchard wrote: > ...to get bounding box information > and to send focus and click events. > > ...manage the canvas subtree You are seem to be assuming a bounding-box/sub-tree model, and I my point is that that assumption does not and will not hold for all canvas-based applications, and I give an thought-example of one where it does not. >> >> One thought experiment I took was this: the canvas represents a bio-reactor, in which various populations of algae, funghi, bacteria etc. are competing. The user can interact with it using a 'virtual pipette' -- adding to the pipette by picking up material in one place, and dropping material from the pipette somewhere else (e.g. by right and left click-and-hold). All the while, the organisms are reproducing, spreading, dying, shrinking, co-existing, etc. In this, there are no 'paths' to test against; rather the application is modelling a fluid situation. The user can learn what the effect of dropping various populations in the midst of others, is. Apart from a legend "right-click and hold to pick up, left-click and hold to drop" (outside the canvas) how does the application convey what is being picked up, what's in the pipette, and what's going on in the reactor, to an accessibility-needing user? "There is a check-box under the mouse, which says "Remember me"" comes nowhere close. This application is not path-based, is not using 'standard controls' and so on. > This is what the ARIA language was setup for, and will continue to work on. > > In your application, the placement of the materials are indeed based on spatial regions. They are path based. No, they are not. There are no regions with well-defined borders that contain only one active element. Every point in the space has a mix, and the proportions in the mix vary continuously over the space. You can pick up from one place, add that mix to the mix in your pipette, and drop some of that mix somewhere else. Where is there a path with well-defined borders? > Consider this visual application you're speaking of -- how would it look in HTML 3.2? That's where I would start, for accessibility. It cannot be done there, at least I can't see how. David Singer Multimedia and Software Standards, Apple Inc.
Received on Friday, 29 July 2011 00:06:15 UTC