Maintain selection when switching layers?

[squatcobbler]

You must get asked this all the time but it's really hard (or impossible) to google for the answer. 

Ubuntu 18.04 GIMP 2.10.14

In photoshop if I select something in one layer, say, a box, and then switch to another layer, the selection box is still there, serving to select something on the other layer.

In GIMP which I switch layers, the selection disappears.  Each layer has it's own selections.

Am I clear, or does that not sense?  

How do I select something in one layer and then keep the selection active when I switch to a different layer?

Since you've been asked this a million times, feel free to point me to a thread that answers this.  (Again this is hard to search for.)

[Ofnuts]

Incorrect. The selection is on the whole image, so you can select something on one layer and move to another layer to use that selection. Your problem may be that the selection markers (aka, "the marching ants") are not visible, so they disappear after you make your selection (but the selection is still there). See View > Show selection (you can also hit Ctrl-T to toggle that setting).

[squatcobbler]

(12-30-2020, 08:01 AM)Ofnuts Wrote: Incorrect. The selection is on the whole image, so you can select something on one layer and move to another layer to use that selection. Your problem may be that the selection markers (aka, "the marching ants") are not visible, so they disappear after you make your selection (but the selection is still there). See View > Show selection (you can also hit Ctrl-T to toggle that setting).

Oh ok I think I understand- there's two selection boxes at the same time.  One for the entire layer and one for what I've manually selected? There's dotted lines around everything, and also a seperate box of what I've selected.  

OK let me rephrase it like this- if I have a layer that only has a circle in the middle; the rest are transparent pixels, how do I select the circle?  In photoshop I'd draw a selection box around the circle and press the up arrow key and the down arrow key and the selection would constrain itself to a selection of the circle.

[Blighty]

(12-30-2020, 10:24 AM)squatcobbler Wrote: Oh ok I think I understand- there's two selection boxes at the same time.  One for the entire layer and one for what I've manually selected? There's dotted lines around everything, and also a seperate box of what I've selected.  

A static dotted line is a layer boundary.
View > Show Layer Boundary

A moving dotted line (marching ants) is a selection boundary
View > Show Selection

Quote:OK let me rephrase it like this- if I have a layer that only has a circle in the middle; the rest are transparent pixels, how do I select the circle?  In photoshop I'd draw a selection box around the circle and press the up arrow key and the down arrow key and the selection would constrain itself to a selection of the circle.

Right click the layer in the layers dialogue
Alpha to Selection

[rich2005]

Quote:...Oh ok I think I understand- there's two selection boxes at the same time. One for the entire layer and one for what I've manually selected? ..

No. not unless you have initially selected everything then made a selection in a different selection mode. Even then adding to an overall selection does nothing.

A little video - 3 and a half minutes - that might answer some of your questions https://youtu.be/7v0EmI6fEQU

[squatcobbler]

(12-30-2020, 12:18 PM)rich2005 Wrote:

Quote:...Oh ok I think I understand- there's two selection boxes at the same time.  One for the entire layer and one for what I've manually selected? ..

No. not unless you have initially selected everything then made a selection in a different selection mode. Even then adding to an overall selection does nothing.

A little video - 3 and a half minutes - that might answer some of your questions https://youtu.be/7v0EmI6fEQU

Woa! That video was just for this post? You're great!  

Yes, the Alpha to Selection is what I was looking for thanks guys.  

I noticed that the keyboard shortcuts aren't next to the menu options- I'll look in the docs for what Alpha to Selection is since I'll be using it a lot.  

Once again, thanks!

[rich2005]

Quote:..I noticed that the keyboard shortcuts aren't next to the menu options- I'll look in the docs for what Alpha to Selection is since I'll be using it a lot. 

Always a good idea to use keyboard shortcuts see: https://docs.gimp.org/2.10/en/gimp-conce...tcuts.html

   

Not many single keys remaining, G J V Y 6 7 8 = ; ' . /  plus some combinations and the F keys - (F2 for example).  You can reassign a never used key combo. The dialogue will warn about a re-assign.

[Blighty]

(12-31-2020, 05:04 PM)squatcobbler Wrote: I'll look in the docs for what Alpha to Selection is since I'll be using it a lot.  

Press the Alt key and click on the layer icon in the layers dialogue.