In Affinity Designer 2, subtracting a Curve from an Ellipse is allowed but does not subtract

[Alan_DeWindt]

Dear Affinity Designer 2 Support,

First of all, thank you very much for making such a great product at an affordable price!  A couple of years back I had enough with the Adobe Elements suite of tools which were becoming way too outdated and, as a hobbyist, could not justify signing up to their expensive monthly subscriptions, so I set out to find something better.  I evaluated many open-source/free and competitor products but when I tried yours I (within minutes!) purchased it.  Yes, you won me over that quickly, and I have been extremely happy, and I might add, thankful ever since!

That said, some things could be improved and I appreciate that you are constantly doing just that.  In that spirit, I am having a problem which I classify as a bug.  I am designing a compass that I will be showing on a small 5" LCD screen to build a flight simulator cockpit.  I want to be able to change the color of the markings on the compass face by making these transparent pixels and changing the color of an underlying layer.  I will code this flight instrument using Python and the PyQt framework on a Raspberry Pi Zero W 2 (which is quite a mouthful!).

My problem:  When I select all of the markings composed of text and Curves and the Ellipse that I want to subtract these from and then press the Subtract icon, the text is subtracted / punched out from the black Ellipse but none of the Curves (markings) are.  So if I start with the below...

...and then do the subtract operation, I am left with this...

The text cleanly punched out of the black ellipse with the blue background coming through but the markings have disappeared into the ether.

If I only select the Curves to subtract these from the Ellipse, the subtract tool is available (which indicates to me that this is a valid operation) but does not work in this scenario either with them simply disappearing and nothing being punched out of the black ellipse.  This is why I am reporting this as a bug, because the subtract operation is available clearly indicating that it is a valid operation which should work, but it does not.

My Affinity Designer 2 file is attached so that you can try this for yourself.  I am on the latest version as of today (2.3.1).

I have spent quite a bit of time browsing through your forum reading through similar issues and tried the solutions that were suggested, none of which worked for me.  This is something pretty basic in my view, which should simply work.  Please advise.

Best regards,
Alan De Windt

Subtract Issue.afdesign

[firstdefence]

• Group all of the text and line marks and group them.
• Duplicate that group and lock the original group 
• Expand the duplicate group and convert the text and numbers to curves
• Select all of the mark lines and use Layers > Expand stroke
• Select the mark line, text and number curves and use Layer > Geometry > Subtract... or
• Layer > Create Compound

[Alan_DeWindt]

Beautiful - thank you very much!!!  This also works for me if all I do is select the mark lines, use Layers > Expand Stroke and then use the Subtract icon to subtract them from the ellipse.  So the Expand Stroke seems to be the trick for Curves that have a stroke.  Put another way, the Subtract operation does not take into account the stroke on curves/lines.

Edited January 10, 2024 by Alan_DeWindt

[v_kyr]

50 minutes ago, Alan_DeWindt said:

So the Expand Stroke seems to be the trick for Curves that have a stroke.  Put another way, the Subtract operation does not take into account the stroke on curves/lines.

Geometrical add/substract etc. needs closed shape paths (aka outlines) thus plain single line strokes have to be to expanded first, in order that the geom operations do work here.

[Alan_DeWindt]

3 minutes ago, v_kyr said:

Geometrical add/substract etc. needs closed shape paths (aka outlines) thus plain single line strokes have to be to expanded first, in order that the geom operations do work here.

That makes sense to me now.  Thank you!

[R C-R]

8 hours ago, v_kyr said:

Geometrical add/substract etc. needs closed shape paths (aka outlines) thus plain single line strokes have to be to expanded first, in order that the geom operations do work here.

Not always. See for example this 2 open curves.afdesign file that has 2 filled open curves. Subtract works because they are filled.

[v_kyr]

1 hour ago, R C-R said:

Subtract works because they are filled.

Make outlines = filled curves.

[R C-R]

1 hour ago, v_kyr said:

Make outlines = filled curves.

Not a normal English language equality, since in English "outline" typically means a line or set of lines enclosing the shape of an object or something similar.