Re: Update on caret tracking

Hi Charles,

Yes, There are some oversights in the decision on the caret tracking
proposal.

I looked again at the existing canvas API spec. drawing and they list
multiple baselines. I was amazed that they referred to a hanging baseline,
an ideographic baseline, and an alphabetic baseline.
We did not specify which one. That is fair. We did not specify alphabetic
baseline. This is typically what I am used to considering a baseline.

Rich

Rich Schwerdtfeger
CTO Accessibility Software Group



From:	Charles Pritchard <chuck@jumis.com>
To:	public-canvas-api@w3.org
Date:	04/13/2011 07:33 PM
Subject:	Update on caret tracking
Sent by:	public-canvas-api-request@w3.org



There's been some movement on the caret tracking proposal:
http://www.w3.org/Bugs/Public/show_bug.cgi?id=11239

There still seems to be some confusion over the TextMetrics.baseline
attribute,
which will apparently need to be "rectified by a future,
separately raised proposal that provides sufficient detail".

If there are any of you on the list that are up for reviewing the prior
proposal, and providing feedback, I'd appreciate it. I posted clarification
of the section on the bug report.

metrics . baseline
"Returns the vertical offset of the anchor point for the text that was
passed to the measureText() method"
http://lists.w3.org/Archives/Public/public-html-a11y/2011Feb/att-0162/HTML_Canvas_2DContext20110217.html



The term -anchor point- is defined in the preceding section on textBaseline
keywords.
"The textBaseline attribute's allowed keywords correspond to alignment
points in the font...
Let the anchor point be a point on the inline box, determined by the
textAlign and textBaseline values"


Here's the link to the working group decision on caret tracking, including
TextMetrics:

--- Comment #12 from Maciej Stachowiak<mjs@apple.com>  2011-04-13 21:01:16
UTC ---
Working Group Decision:
http://lists.w3.org/Archives/Public/public-html/2011Apr/0271.html