[CREATE] [OpenRaster] Layer colorizing (and other non-separable blend modes)

[Boudewijn Rempt]

On Thursday 26 July 2012 Jul, Andrew Chadwick wrote:
> OpenRaster should be able to store layers which colorize or set the
> lightness of underlying pixels. It's a commonly requested feature from
> artists using MyPaint.
> 
> Given the active Editor's Draft from the W3C CSS-SVG Effects Task
> Force which is up at
> 
> http://dvcs.w3.org/hg/FXTF/rawfile/tip/compositing/index.html
> 
> would anybody object to my adding the following composite-op values to
> the OpenRaster Layers Stack specification[1] using the following new
> bullet point:
> 
> """
>   * In addition, the following non-separable compositing operations
> are defined in the (SVG, Canvas and CSS) _Compositing and Blending 1.0
> Editor's Draft_[[link]]: svg:color | svg:luminosity | svg:hue |
> svg:saturation.
> """
> 
> Of interest, they're the non-separable blend modes defined in the PDF
> specification and also in the Cairo compositing operators docs[2].
> 
> There is sample code available at
> https://gitorious.org/~achadwick/mypaint/achadwick-mypaint in the
> branch "layer-colorize-2" which implements the Color and Luminosity
> blend modes. I would like to push this branch to the MyPaint
> development master reasonably soon.
> 
> Would the Krita and GIMP folks reading this be OK with the change
> outlined above?
>

No objections. I suspect that Krita already supports those blending modes anyway :-) I just need to check to which ones these two actually map.

-- 
Boudewijn Rempt
http://www.valdyas.org, http://www.krita.org, http://www.boudewijnrempt.nl