- From: Aryeh Gregor <Simetrical+w3c@gmail.com>
- Date: Thu, 5 Nov 2009 18:37:18 -0500
- To: Brad Kemper <brad.kemper@gmail.com>
- Cc: Dean Jackson <dino@apple.com>, Simon Fraser <smfr@me.com>, "Tab Atkins Jr." <jackalmage@gmail.com>, www-style list <www-style@w3.org>
On Thu, Nov 5, 2009 at 6:24 PM, Brad Kemper <brad.kemper@gmail.com> wrote: > On Nov 5, 2009, at 2:55 PM, Dean Jackson <dino@apple.com> wrote: > >> Yes, where the X-axis points left and the Y-axis points down, and positive >> 90deg being the angle taken from the X-axis to the Y-axis (ie. clockwise). > > Well, that's just crazy talk. X-axis points right and Y-axis points up in > the geometry textbooks I've seen. Even for background-position, X points > right, not left. I'm pretty sure he meant the X-axis points right. All the mathematics I know has the Y-axis pointing up, but it seems like in computer graphics, the Y-axis often points down. It's confusing to me too, coming from a mathematical background, but it's better to stick to the convention already used in CSS.
Received on Thursday, 5 November 2009 23:37:57 UTC