[Gimp-developer] layer multi-select

[Matthew Smith <melkor orangepalantir org>]

Hello

I am going to make an effort to get a layer multi-select going. In this 
email I will outline what I hope to achieve and I am asking what would 
be the most effective way to go about submitting a patch that could get 
accepted.

The goal is to be able to select multiple layers, and perform actions on 
the set of selected layers as a whole. Initially the actions would be 
limited to changing the visibility, changing the locked, or moving the 
selected layers to a group. This would be different than creating a 
group of layers because it would be easier to select additional layers 
in the layer dialog by using shift + click for a range of layers or 
ctrl+click to add/remove a layer from the currently selected.

To implement this I want to add multi-select to the layers dialog. Then 
when there are multiple layers selected an action would check for 
multiple layers selected and act accordingly. Similar to using a layer 
group.

I can see writing this two different ways, I am open to suggestions for 
more though. The first way is to use the actual layers dialog and add a 
multi-select to the dialog. Then modify individual actions to check for 
a multiple selection. The second way would be to create a plugin that 
makes a duplicate "layers dialog" with multiple selection. This dialog 
would allow actions that are performed on multiply selected layers.

I have only briefly looked over the code, and I am open to suggestions. 
I think either way would be non-intrusive in the current selection model 
and allow some migration, such that if it works then actions can be 
migrate to using the selected layers instead of the active layer.

Thank you
Matt