In Affinity Designer 2 how can I select an area of a pixel layer?

[bobdobbs]

In AD2 I have imported a png image.
I'd like to delete a rectangular part of that object while leaving the rest of that object.

Initially I tried the marquee rectangular selection tool within the pixel persona.
But if I select a part of a png object with the marquee tool, the 'cut' 'copy' and 'delete' do not work in the way I'd expect.

Sometimes these operations become unavailable - they are greyed out in the menu.

Sometimes the 'cut' operation is available in the menu. But activating it while having selecting an area of the png layer will delete the entire layer: not just the selected area.

Also, the marquee rectangular selection tool can't be used to select parts of a png that are outside of the canvas.

I've got the official documentation for the marquee tool open in front of me, but I'm not seeing any clues in that documentation about why it doesn't behave like a normal selection tool.

Why doesn't this tool behave the way that I expect it to?
Is there another tool within Designer I can use for this purpose?

 

[GarryP]

If you have placed the image into the document you will have an Image Layer but to make a pixel selection from that image you will need a Pixel layer .

To get a Pixel layer, you need to Rasterise the Image Layer (one way is to right-click the layer on the Layers Panel and choose Rasterise) before doing the pixel selection.

[Pšenda]

1 hour ago, bobdobbs said:

I've got the official documentation for the marquee tool open in front of me, but I'm not seeing any clues in that documentation about why it doesn't behave like a normal selection tool.

I think that the need to rasterize the Image object should be explicitly mentioned in the Help. Although it is obvious from the wording "Pixel selections", because the Image layer is an object/container, not an area of pixels as is the case with the Pixel Layer, but this fact is not well known and automatically assumed.

[R C-R]

9 hours ago, bobdobbs said:

But if I select a part of a png object with the marquee tool...

If you place a PNG file into an Affinity document, it is not a "PNG object," just an Image layer. See for example https://affinity.help/designer2/en-US.lproj/pages/Layers/layerImage.html for more about this special type of container layer, & how to convert it to a Pixel layer.

You can see a list of all the layer types & their layers panel icons at for instance https://affinity.help/designer2/en-US.lproj/index.html.