Ruling canvas out for text editing March 30, 2010
Wrote a quick prototype using canvas as a text editor but have now abandoned it in favour of a contenteditable block with canvas overlays.
The problem for non fixed width fonts is that there’s no way of measuring where each character starts and ends. Due to kerning, aliasing etc. eg {measureText(and again) != measuretext(an) + measureText(d again)} which would be expected. But there’s no way of getting the character offsets of ctx.fillText call. I wrote a quick and dirty manual measure by getting the canvas as an image and finding the start and end pixel of characters but it felt like too much work and contenteditable was just there.
The thing stopping me using contenteditable in the first place was obtaining the screen co-ordinates for the selection is not possible at the moment as far as I can tell. IE has boundingWidth … but firefox or the w3c std doesn’t seem to support this. I’m interested in word selection, not multiparagraphs. As a workaround I clone the contents, surround the word with a div and calculate it’s location and then replace with the original content again, reselecting the original selection. Seems to work ok in both firefox and webkit browsers.
feedback March 29, 2010
Javascript, scala and web applications. I don’t think it’s possible to understate the velocity it’s possible to have when there’s less in the way.
Mercurial tip of the day March 22, 2010
If you’re on a mac and using murky and an authenticated store like bitbucket to push changes to, you can to edit your .hg/hgrc in the form of https://username:password@bitbucket to include your password which will allow a push to work from the push button. If anyone gets access to your machine they can now muck with the repository, but then again you’re probably already up the creek in that case.
Murky, the best mercurial client I’ve used on windows and mac; at this stage doesn’t support prompting you for credentials in response to authentication request, but it’s a pretty easy workaround.
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