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[whatwg] [WebApps] canvas transform()/setTransform()

From: 黒澤剛志 <taken.spc@gmail.com>
Date: Thu, 28 Dec 2006 11:02:05 +0900
Message-ID: <646543300612271802g56908cc6m6b7ef39fdbca3666@mail.gmail.com>

Web Application 1.0 adds the transform() and the setTransform() to the
canvas 2d context.
The conversion of the arguments of these methods to the matrices is
described in the section

> The transform(m11, m12, m21, m22, dx, dy) method must multiply the current transformation matrix with the matrix described by:
> m11  m12  dx
> m21  m22  dy
> 0     0     1
> The setTransform(m11, m12, m21, m22, dx, dy) method...
- http://www.whatwg.org/specs/web-apps/current-work/#transform

However, this is repugnant. And it isn't compatible with many graphics
systems. So the matrix should be

m11  m21  dx
m12  m22  dy ... (b)
0     0     1

In addtion, the rhino-canvas implements both methods. It uses the matrix (b).

KUROSAWA, Takeshi - http://taken.s101.xrea.com/
Received on Wednesday, 27 December 2006 18:02:05 UTC

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