Re: [Gimp-gui] Multi-layer selection

[Ofnuts <ofnuts gmx com>]

On 10/10/15 15:58, Jehan wrote:
> Hi,
>
> On 2015-10-09 23:15, Ofnuts wrote:
> > On 09/10/15 14:44, Jehan wrote:
> >
> > > So should we have these 2 concepts?
> > > If we have multi-selection, do you have a concept of "main selected
> > > layer", which is the one where drawing occurs? Is it then the first
> > > of the last selected layer?
> >
> >  Actually you end up with three selection concepts:
> >
> >      * selection for painting (single selection)
>
> Right, this can be considered as a different selection concept. This 
> said, it seems nobody really want to disrupt the idea that painting 
> can only occur for a single layer at a time.

Yes, that's why in the end we have three selection types/concepts. We 
have to keep that one (that also applies to copy/paste ops, by the way).

> >      * selection for geometric transform (actually faked as 'links')
> > (even if links also apply to non-layer things, such as paths and
> > channels)
> >      * selection for operations/management (drag/drop in the Layers 
> > list,
> > possibly drag/drop to another image, set visibility, mode, opacity,
> > alpha/pixel lock, links, add alpha channel... , remove text
> > information, text-to-path...)
>
> So a question can be: is this a problem? Is it meaningful for these 
> concepts to be separated?

Good question. The "link" selection applies across different types of 
objects so could be considered different (what happens to linked paths 
when you just reorganize layers in the layers list? What happens when 
you delete some thing in one list, should linked items of other types be 
deleted too? IMHO the current "links" are a bit insufficient anyway 
because you cannot permanently link two distinct sets of items, I'd love 
to have a way to tell Gimp that these two layers and this path should 
always be transformed together, while these three other layers and that 
other path are also always related.

> > In addition to this you have to consider how scripts can use this.
> > Most currently trigger on the link or visible flags so having a third
> > flag could be good.
>
> Of course, everything will have to be considered, API included. The 
> spec will have to be as exhaustive as possible and handle every case 
> of layer modification: what should happen when several layers are 
> selected?
>
> Even when keeping different selection/link concepts, it may also be 
> the chance to write down the spec for linked layers too, and clarify 
> how API should behave with linked layers, by the way.

Repeating the action on selected items can be left to the scripts and 
plug-ins, if they are provided an API to retrieve the selected items.


> Since I think that these changes won't be for GIMP 2.10, then probably 
> for GIMP 3.0 instead, API changes may occur, if not mistaken.
>
> Jehan