is it me or is it Gimp?

[Ofnuts]

In the attached XCF (small!: 5x5pixels), there are 4 layers: 1, 2, 3 and the problem layer, "Numpy Ops" (which is identical to "1", with one red and one blue square). For me, this layer:

• Shows in the Layers list, but behave as a transparent layer in the Image window.
  
• Remains invisible if I copy/paste it over itself (Ctrl-C,Ctrl-V,Ctrl-H)
  
• Produces a visible copy if I copy it as a new layer (Ctrl-C,Ctrl-V,Ctrl-Shift-N)
  
• Can be painted over, but the painting only shows in the Layers list
  

Is it the same for you?

The layer is produced using the "pixel region" API for Python...

[Blighty]

Duplicate - problem
Copy/Paste/New Layer - OK
Export png - problem

[Ofnuts]

Hmmm. Actually the layer has an opacity of 0... So it's me... Found the problem

[Blighty]

(12-04-2017, 04:03 PM)Ofnuts Wrote: Hmmm. Actually the layer has an opacity of 0... So it's me... Found the problem

I should have noticed that but didn't.

[Ofnuts]

So I found how to copy pixel data from Gimp into a numpy array, and vice versa. Numpy is a popular fast math library for Python. For instance implementing a median filter with it takes 40 lines and runs in four seconds over 4 copies of a 20Mpx layer (a plain average filter is 1.2s). This can be handy some day.

[Ofnuts]

(12-04-2017, 04:08 PM)Blighty Wrote:

(12-04-2017, 04:03 PM)Ofnuts Wrote: Hmmm. Actually the layer has an opacity of 0... So it's me... Found the problem

I should have noticed that but didn't.

Being two people fooled is somewhat comforting. I may have senior moments but that wasn't one of them.