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

From: Stefan Haustein <sh@kobjects.org>
Date: Mon, 15 Jan 2007 16:36:32 +0100
Message-ID: <45AB9F80.9010307@kobjects.org>
Hi,

could somebody please clarify whether the unusual parameter order is
intended -- or simply a bug in the specification?

Best regards,
Stefan


????(KUROSAWA, Takeshi) wrote:
> Dear WHATWG,
> 
> 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 3.14.6.1.2.
> 
>> 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).
> http://rhino-canvas.sourceforge.net/
> 
> regards.
Received on Monday, 15 January 2007 07:36:32 UTC

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