noise generators (forked from: Krita user community?)

Matthew Woehlke mw_triad at
Thu Feb 28 18:09:07 CET 2008

Boudewijn Rempt wrote:
> It's going to be nearly impossible to take the alpha channel out-of-band in 
> Krita. It is possible to add a transparency mask, though.

Yes, when I thought about it further, I realized PS/GIMP's model is 
RGB(A) channels (of which I often don't use the A), plus a 
single-channel layer mask "M", where the actual alpha of the layer as a 
whole is A * M.

So... what I was actually thinking is to have a generator for the data 
channel outputting K (grayscale, no alpha), with a different generator 
outputting M (the mask)... possibly as separate layers, so long as there 
is a reasonable way to combine them to achieve the desired effect. And 
in fact the gradient mapping should be K->RGBA, not K->RGB.

So nothing horribly obscure here :-).

> On Tuesday 26 February 2008, Matthew Woehlke wrote:
>> Which means, I think, that we still have two kinds of nodes (filters and
>> "regular"),
> Well, not quite-quite. In krita, there are two types of nodes: layers and 
> masks. Layers are nodes that are composited together in a stack, and masks 
> are nodes that affect the layer they are associated with. We've got the 
> following types:

Ok, clearly our terminology is different... I'm calling a "node" what 
you get when you take a layer plus optional masks, i.e. a "line item" in 
the stack (at least, as it would be in PS/GIMP).

> layers: group, adjustment, paint, copy (and, potentially, generated)


> masks: transparency, filter, transformation, selection

Um... ok, I guess I don't get how a filter works, then, or why a filter 
is a mask and an adjustment is a layer. For that matter, how is an 
adjustment not a filter?

(A group layer is one which combines two projections?)

This would be good information to have on that wiki page I want to start 

> Wether we'll allow mask nodes to be nested remains to be decided, I think it 
> could be useful, but it could also be too hard for users to work with.

PS lets you nest paint and vector masks (not sure how that would work 
with krita since I assume we have karbon flakes), but... I would 
definitely like to be able to apply a paint mask to a filter. Maybe, 
nesting of masks should be allowed with the caveat that you cannot nest 
more than one of a type.

Alternatively, do as I suggested earlier and have a composition mode 
that is equivalent to nesting, but with separate nodes :-).

Somewhere, there is a .sig so funny that reading it will cause an 
aneurism. I haven't found it yet, but I think I met a few of the runners-up.

More information about the kimageshop mailing list