Designer 2: Separating non-touching shapes from a single curve

[NightCabbage]

Hello

I am new to Affinity Designer 2, and am trying to do something very simple with it but am surprised it doesn't seem to be able to actully do it... maybe I am missing something.

To set up a very basic scenario to show my problem...

1. Create a large circle
2. Create a medium circle inside that one
3. Select them both and do a "Subtract"
4. Create a small circle insde the hole
5. Select them both and do an "Add"

(I've added an image to show the curve shape I'm talking about)

Now, how can you separate the small circle and the large ring into 2 separate "objects" or "curves"?

The only option I seem to have is to "Separate curves" or "Divide" but both of these appear to do the same thing in this case, which is "wrong"... and that is to give me 3 filled circles, instead of 1 large ring and 1 small circle.

In other software, either the 2 shapes (ring and circle) are already treated as 2 separate objects, or at a minimuim, they are easily separated with an ungroup or break apart operation. ie. the software knows that these are in fact 2 non-touching vector shapes, even if they're technically currently stored in the same curve.

Obviously this example is trivial, but sometimes I'm importing SVGs with a hundred vector shapes (often nested, with holes, etc.), and Designer 2 treats them as the same single curve, and I can't spend hours separating the pieces... I feel like this is such basic and foundational functionality that I must be missing something?

Thanks!

 

[Komatös]

5 hours ago, NightCabbage said:

Hello

...

In other software, either the 2 shapes (ring and circle) are already treated as 2 separate objects, or at a minimuim, they are easily separated with an ungroup or break apart operation. ie. the software knows that these are in fact 2 non-touching vector shapes, even if they're technically currently stored in the same curve.

Obviously this example is trivial, but sometimes I'm importing SVGs with a hundred vector shapes (often nested, with holes, etc.), and Designer 2 treats them as the same single curve, and I can't spend hours separating the pieces... I feel like this is such basic and foundational functionality that I must be missing something?

Thanks!

Probably you just overlooked it, alsoi n the Affinity programs there is beside the Circle Shape Tool also the Ring Shape Tool.

If you do not see the multiple selection icon, go to View and select Customize tools.
 

[GarryP]

Welcome to the forums @NightCabbage

In your basic example, when you Subtract the large- and medium-sized circles you create a Curves layer containing two curves. Neither of these curves ‘understands’ a relationship with the other one; they are simply disconnected curves which happen to be part of the same Curves layer.

Similarly, when you Add that Curves layer to the small circle you are creating a Curves layer which contains three curves, the two from the original Curves layer and another from the small circle.

None of the curves in the new Curves layer have any relation to each other, they are all just separate curves.

Thus, when you separate the curves you will get three separate Curve layers.

If you want to create the shape you describe, but create it differently, then there are options such as Compounds or the Donut Tool, but, since you are working with curves which come from an SVG file then your options may be limited.

If you can (legally) supply us with an example SVG and give us precise instructions as to what you want to isolate from that file then we can experiment with it to see what’s what.

Otherwise we can only guess since each situation will be different.

[Return]

What I find strange is that you first have 2 objects added together and next you want it to be 2 objects.
So why adding them in the first place?

[GarryP]

3 minutes ago, Return said:

What I find strange is that you first have 2 objects added together and next you want it to be 2 objects.
So why adding them in the first place?

I think, by way of a simple example, the OP was giving us a way to see what the problem was without the extra complications of the real SVG.
In other words, the circles example is not what they have to deal with, it’s just to show us the sort of problem they have.

[Return]

I got that but it is a bad example as to what the OP wants to see in a real design situation.
I would use, as mentioned, the donut/ring shape for this and make a compound or group and be done.

[GarryP]

I think my point - for anyone reading this - is that (as far as I can tell) they are not trying to make the design containing the circles; the design with the circles is just a simplistic example of their actual starting position.

Having said that, I agree that it’s probably not a great example since it doesn’t sound like its representative of the real problem they are facing, which we can only see with a real example of an SVG.

[Return]

And coming back to the issue.
Affinity doesn't create a new shape when subtracting.
It actually adds an inversed vector object to it to make it visual look like one shape.
Take a look at the layers panel when subtracted.
First it is an ellipse aka curve and after subtraction it is named curves.
That's why it becomes 3 shapes when dividing or separating curves.

I just tried the same in XaraDesignerPro+ and get the same results aka giving me 3 shapes also.
 

[Return]

Also tried it in the new Inkscape 1.3 and it also gives 3 paths(shapes)
 

[NightCabbage]

1 hour ago, GarryP said:

Welcome to the forums @NightCabbage

In your basic example, when you Subtract the large- and medium-sized circles you create a Curves layer containing two curves. Neither of these curves ‘understands’ a relationship with the other one; they are simply disconnected curves which happen to be part of the same Curves layer.

Similarly, when you Add that Curves layer to the small circle you are creating a Curves layer which contains three curves, the two from the original Curves layer and another from the small circle.

None of the curves in the new Curves layer have any relation to each other, they are all just separate curves.

Thus, when you separate the curves you will get three separate Curve layers.

If you want to create the shape you describe, but create it differently, then there are options such as Compounds or the Donut Tool, but, since you are working with curves which come from an SVG file then your options may be limited.

If you can (legally) supply us with an example SVG and give us precise instructions as to what you want to isolate from that file then we can experiment with it to see what’s what.

Otherwise we can only guess since each situation will be different.

 

1 hour ago, GarryP said:

I think, by way of a simple example, the OP was giving us a way to see what the problem was without the extra complications of the real SVG.
In other words, the circles example is not what they have to deal with, it’s just to show us the sort of problem they have.

 

1 hour ago, GarryP said:

I think my point - for anyone reading this - is that (as far as I can tell) they are not trying to make the design containing the circles; the design with the circles is just a simplistic example of their actual starting position.

Having said that, I agree that it’s probably not a great example since it doesn’t sound like its representative of the real problem they are facing, which we can only see with a real example of an SVG.

Thank you Garry, yes, that is exactly what I was trying to ask - not how to create any shapes, but how to separate existing shapes that are a single curve. I was just setting up a simple example to demonstrate the problem. Generally, we're importing SVG files, but they always have a single curve representing the entire set of many shapes.

I will attach one such svg file.

Now I'm not a huge fan of Adobe software, but when I import an SVG there, I can select each vector shape individually.

 

Whereas in Designer 2 when I try to separate, I get this...

 

I understand that the object is simply a list of curve interacting with eachother to create shapes and holes in shapes, etc.

But I am unsure how I can separate the different "shapes" without having to spend a lot of time on the individual pieces.

In this example, there are only 2 "shapes" - the phone and the chat bubble. But sometimes there may be 20 or 30. I don't want to have to cut them out individually, or worse, re-apply boolean subtracts on multiple curves to re-create holes, etc.

I hope that all makes sense, happy to provide any additional information or examples.

Thanks

sms.svg

[NotMyFault]

Unfortunately, Affinity doesn’t have the same „object detection from curves“ function.

 

One way to go in Affinity Apps is the node tool. If you want to divide objects, copy it as many times as required.

Then use the node tool, with alt-modifier key you can drag a lasso around the parts you want to delete, and click delete. 

[Return]

8 minutes ago, NotMyFault said:

Then use the node tool, with alt-modifier key you can drag a lasso around the parts you want to delete, and click delete. 

This works but is by no means faster as opposed to just dividing and subtracting the items again.
 

 

 

[NotMyFault]

Just now, Return said:

This works but is in no means faster as opposed to just dividing and subtracting the items again.

Depends. Using node tool preserves „locality“ - you don’t need to reselect layers again, in more complex cases where you would need a cascade of subtract / add it can be much faster. Choose your poison 

[v_kyr]

Either way it's not that difficult to build two seperate objects (in this icon case) out of one curves object. In order to keep/have them still together just group or compound them.

• sms.afdesign

[Return]

4 minutes ago, NotMyFault said:

Depends

Of course it is depending on the given situation but that is always the case. 😉

 

[GarryP]

2 hours ago, NightCabbage said:

I will attach one such svg file.

Thanks for sharing the SVG.

Looking at the SVG code, the design is a single path.

As such, there’s no way for the software to ‘know’, once the various curves have been separated, which curves are ‘with’ other curves, it’s just a bunch of curves ‘concatenated’ into one path.

Other software may have some kind of neat functionality to automatically ‘guess’ which curves are related to other curves – maybe by calculating which curves are (fully?) enclosed by other curves – but the Affinity applications don’t currently have that.

As has been shown above, in this case it only takes a couple of Geometry/Boolean function applications to ‘fix’ it, however this will, of course, become more of a chore when the number and complexity of curves increases.

On the other hand, the Shape Builder Tool (in Designer only) seems to do a good job with this and it’s only a few extra clicks (but it still leaves a single Curves layer).

This sounds like a good candidate for a feature request to me – some kind of “Separate into geometry” functionality.

Edited July 26, 2023 by GarryP

[R C-R]

8 hours ago, GarryP said:

On the other hand, the Shape Builder Tool (in Designer only) seems to do a good job with this and it’s only a few extra clicks (but it still leaves a single Curves layer).

It seems to take just one click on the "+" (Add) button after selecting all but the 4 interior rectangles, or am I missing something?

[Return]

8 hours ago, GarryP said:

This sounds like a good candidate for a feature request to me – some kind of “Separate into geometry” functionality.

 

[Return]

34 minutes ago, R C-R said:

It seems to take just one click on the "+" (Add) button after selecting all but the 4 interior rectangles, or am I missing something?

Separating.

[v_kyr]

9 hours ago, GarryP said:

Looking at the SVG code, the design is a single path.

As such, there’s no way for the software to ‘know’, once the various curves have been separated, which curves are ‘with’ other curves, it’s just a bunch of curves ‘concatenated’ into one path.

Other software may have some kind of neat functionality to automatically ‘guess’ which curves are related to other curves – maybe by calculating which curves are (fully?) enclosed by other curves – but the Affinity applications don’t currently have that.

That's manually possible by inspecting path commands in code (though very tedious for huge paths), but in practise I don't know if any vector app offers something like that here function wise automatically then. At least I've not used or seen such SVG based tools so far. - However, since tracing tools can do that sort of recognition, but instead on a pixel base (combining or separating detected pixel lines), it's possible that some clever vector tools offer similar things on a vector bezier curves level. So performing the oposite to the SVGO/SVGOMG optimizer, aka separating combined SVG paths.

1 hour ago, Return said:

That's just a single shape object (so one curve obj) with fill & stroke and so not exactly the same here. Performing an Expand Stroke on that will work on a shape or single curve here. - But try instead an Expand Stroke on combined curves here (like the OP's curves/svg path icon) and see if that would be of any usage at all here ...