Erash Brush Tool

[Taxicab Messiah]

The Erase Brush Tool acts in ways I don't understand.  When I try to erase the stroke lines of a rectangle it auto-creates a mask to remove the image.  But when I erase another object (like my background layer in this screenshot) no such transition occurs and it simply operates as I expect.  What gives?

[Taxicab Messiah]

Not only that, but in this example, you can see that the eraser brush not only erases my background marble texture pixel layer...but also the black rectangle layer underneath - erasing 2 layers!  While erasing only 1 layer (or none via a mask) when applying the brush to my red rectangle.  Rhyme and reason I am not finding.

[Old Bruce]

13 minutes ago, Taxicab Messiah said:

  When I try to erase the stroke lines of a rectangle it auto-creates a mask to remove the image.  But when I erase another object (like my background layer in this screenshot) no such transition occurs and it simply operates as I expect. 

The rectangle is a vector object. The Erase brush will work on Pixels, not Vectors. So the application makes a mask to block it. The alternitive would be to rasterize the rectangle to a pixel layer before trying to erase.

8 minutes ago, Taxicab Messiah said:

Not only that, but in this example, you can see that the eraser brush not only erases my background marble texture pixel layer...but also the black rectangle layer underneath - erasing 2 layers!  While erasing only 1 layer (or none via a mask) when applying the brush to my red rectangle.  Rhyme and reason I am not finding.

Not really seeing this. I think I would need to be aware of how the document was made in order to see it.

[Taxicab Messiah]

If shapes are vector objects in Affinity Photo - objects that scale infinitely - then why can I see pixels on the vector object?

[R C-R]

16 minutes ago, Taxicab Messiah said:

If shapes are vector objects in Affinity Photo - objects that scale infinitely - then why can I see pixels on the vector object?

It's because AP always displays documents using the pixel view mode, forcing curved objects to display with antialiasing visible. If you have AD, open the same document, & do not use any of its pixel view modes, you will see that the vector shapes are actually resolution-independent.

[Old Bruce]

20 minutes ago, Taxicab Messiah said:

If shapes are vector objects in Affinity Photo - objects that scale infinitely - then why can I see pixels on the vector object?

Because Photo will always show a pixelated view. As it is made to work primarily with pixel art it makes a certain amount of sense to show everything as it will appear as a photograph would.

[Taxicab Messiah]

Well they certainly don't reveal themselves to be vector objects when exported from AF either.

[Old Bruce]

5 minutes ago, Taxicab Messiah said:

Well they certainly don't reveal themselves to be vector objects when exported from AF either.

Exported as SVG? Or as a PNG?

[Taxicab Messiah]

.svg on attempt number 2 - Good catch!  Ok not totally useless.