W3C home > Mailing lists > Public > www-svg@w3.org > July 2012

Re: Compositing math in SVG

From: Nikos Andronikos <nikos.andronikos@cisra.canon.com.au>
Date: Wed, 11 Jul 2012 13:48:36 +1000
Message-ID: <4FFCF794.9090705@cisra.canon.com.au>
To: <www-svg@w3.org>
Hi,

On 11/07/2012 11:46 AM, Calculemus wrote:
Ok, I have confirmed your math matches the math in here:

http://www.pegtop.net/delphi/articles/blendmodes/

I have two sources for blend modes so far with same math.
Will keep checking other sources, and confirm multiple times
the math for each blend mode.

But it seems you have very little number of blend modes.
There are many more blend modes in the web site I gave
above. Although I don't know how much to trust that, since
the person says he invented some of those. What do you think
about this?
There is no limit on the number of blend modes that exist. A blend mode is merely a named function that takes two input colours and outputs one colour.
As you've found out, there's no guarantee that blend modes with the same name will be implemented the same across different software.
This may partly come from the fact that, initially, Adobe didn't make the formula for their blending functions publicly available and so they were reverse engineered.

For now, we have chosen to align with the blend modes offered in the Adobe suite of graphics applications as these are well known and well supported.
Authors may request more blend modes once the draft for the Compositing and Blending specification is officially made public. The working group will of course consider those requests then.

Thanks for helping!


The information contained in this email message and any attachments may be confidential and may also be the subject to legal professional privilege. If you are not the intended recipient, any use, interference with, disclosure or copying of this material is unauthorised and prohibited. If you have received this email in error, please immediately advise the sender by return email and delete the information from your system.
Received on Wednesday, 11 July 2012 03:49:07 GMT

This archive was generated by hypermail 2.3.1 : Friday, 8 March 2013 15:54:51 GMT