- From: Charles Pritchard <chuck@jumis.com>
- Date: Fri, 26 Nov 2010 11:53:06 -0800
All, You may have seen me posting to the list, posting defects related to the accessibility of the Canvas element. If you've followed those threads, you've seen others on the list rebuke my use cases, as inappropriate uses of existing APIs. This has happened twice, recently. In both cases, I've brought to light simple defects in the current WHATWG specs, and proposed that attributes be exposed to the scripting environment, to address the defects. My first proposal was that 'baseline' be added to measureText. My second proposal was that the CSS pixel ratio be exposed to the scripting environment, through window and/or window.screen. In response to this, I've been told: one, Canvas should not be used for rich text editing and two, Canvas bitmap resolution should not be managed by the author. These responses are grounded in a reasonable philosophy, and my purpose, in this thread, is to bring that philosophy to discussion, so it might be explicitly stated, and I might better understand the scope of this mailing list. Canvas is a low level API. There are very few of them in the WebApps / HTML specs. I'd say that Typed Arrays [ArrayBuffer] is another low-level API. They're certainly revolutionary, in what they offer programmers, in terms of control and expressiveness. These APIs allow WebApp authors the same flexibility and control as classical desktop application developers. Many on this list have commented that low level management will lead to poor use and misunderstanding by unknowing developers: essentially, that we should not give developers another tool to shoot themselves in the foot. I've spent some time discussing the merits of that particular concern. Though I have stood my ground, I've not convinced others on this list that my use cases are valid. I want to suggestion a reason for this impasse: the WHATWG intends to produce a scene-graph specification. Other activities are out of scope. At some point, and this does reoccur, there was a separate WebApps spec. This was merged into the hypertext spec, leading to the current work product. There were good reasons: many WebApps APIs are named and based upon corresponding hypertext attributes. Scripting is as ubiquitous as scene rendering implementations. Merging these two specs meant a broadening of scope, in the single work-product. Fantastic work is being done in relation to CSS, DOM and HTML elements. I couldn't be more pleased. That said, the editor of the WHATWG and some implementers are of the mind that they are working on a hypertext standard (seems fair, considering the group name), one that will be implemented, universally, by browser vendors. That's great, but it neglects the history of the WebApps specifications and use cases. Is the WHATWG the proper forum for discussion about WebApps, or is such discussion better left to the W3C WebApps group and associated groups? These applications have radically different constraints and use cases than the standard and accessible presentation of markup -- of hypertext documents. With the group focused on developing a standard scene-graph, I understand completely why text-editing should be left to HTML Next Form elements, and I understand why bitmap resolutions should be declared within the CSS/HTML scene graph. If the group also intends to support WebApps, which do not operate exclusively under a scene-graph, and are instead operating under a WebIDL-based scripting environment, then these scope restrictions are wholly inappropriate. There is a lot of room for growth in WebApps. They straddle the browser extension / scripting environment sandbox divide. Some implementers may see that divide as something separate from the WHATWG. Let me know your opinion on the matter. I think it'd be reasonable to limit the scope of WHATWG, and develop WebApps under a separate list and group. At the same time, I would prefer, and hope, that WebApps can be discussed within the WHATWG. Thank you all, for engaging in discussion, here, in the open. -Charles
Received on Friday, 26 November 2010 11:53:06 UTC