[Gimp-user] Questionable implementation of layer list / groups

[rich404 <forums gimpusers com>]

> Maybe there aren't that many people using Gimp who find the
> implementation of layer groups confusing and non-intuitive.

Coming from some other application perhaps, still not familiar with Gimp. Nobody
pretends that Gimp works the same as 'some other' graphics application - why
should it? There is a learning curve

> I work with projects of around 100 layers and being able to do normal
> things that we can do when managing files in a file manager window or
> lots of other applications with a list of things, to find Gimp has its
> own idiosyncratic limited implementation of a list of layers is very
> frustrating.
>
> Some examples
> - if I have selected a layer group then I should be able to drag that
> whole group of layers in the canvas to a new location. After all I can
> drag that layer group to a new location in the layer list. But hello!
> I can't drag the group of layers together in the canvas unless I go
> through every layer in the group and turn on the link to join them all
> together. And then turning off the link on other layers

The move tool has a 'Move the active layer' toggle useful if a layer (such as
text) has lots of transparency. The Gimp move tool will find the first layer
with a solid pixel under the cursor. However for a layer group, with the cursor
on the layer group icon in the layer dialogue the whole group moves.

> - I can't just select all the layers in the group and apply the link
> to all of them at once because the layer list can only ever have one
> item selected at a time. Same applies to the other types of operations
> like the different types of locks.

This works the same in any Gimp image. Hold the shift key down and links are
toggled on/off A layer group is treated as a regular layer. The same applies
inside a group. Shift-click on the link icon toggles on/off inside the layer
group.

> The other problem is creating a layer group uses up unnecessary
> additional resources beyond what is needed to simply group layers
> together in the layer list or on the canvas. This can add unwanted
> gigabytes to a large project file on disk and slow down a lot of
> operations significantly.

True. However the size (in memory) depends on the size of the layers. Just made
a small example - 20 layers and as percentages.

All layers the size of the canvas as a base value: 100%

Two layer groups added to include some layers: 107%

but what happens if the layers are cropped to a minimal size for the contents

All layers:  10%

Plus two layer groups: 15%

Obviously depends on the layer contents but might save you some memory and file
size. There are shortcuts to crop layers to the contents.

> Please consider that now that projects can be greater than 4 GB in
> size, there are people out there working with 30 GB projects with
> large numbers of layers who really need better ways of managing them.

There are but not that many. 

One thing that does come up now-and-again with large projects is saving the
image. Do be careful. Make sure that the save is complete. There is a progress
indication bottom of the image window. Closing Gimp while saving-is-in-progress
has led to disasters. The developers have made this better than it used to be
but.... Same as any application, keep backups, save frequently. There is no
automatic periodic-save at the moment, it is up to you.

-- 
rich404 (via www.gimpusers.com/forums)