divide path by another one

[SgtPepper007]

Hi,

 

is it possible in Affinity Designer to divide overlapping paths?

If I have i.e. two paths that overlap I would like to achieve that i.e. the path below gets divided into two separate paths where the upper path crosses the lower one.

 

Thanks

SgtPepper007

[MEB]

Hi SgtPepper007,

Welcome to Affinity Forums :)

Yes, but you can only perform this operation between closed paths. You cannot do it between an open path (line) and a closed path (shape) or between two open paths (lines) - check the menu Layer ▸ Geometry ▸ Divide. 

So to break a shape you have to use the Node Tool to create nodes where you want to break the shape then, select them and click Break Curve from the Action section in the context toolbar.

We already have a Knife Tool planed which (see designer's roadmap) may help with this later (i don't know much details about it yet).

[Alfred]

You cannot [perform this operation] between an open path (line) and a closed path (shape) or between two open paths (lines) - check the menu Layer ▸ Geometry ▸ Divide.

 

Perhaps you shouldn't be able to 'divide' two (intersecting) unclosed curves, but I find that AD on Windows beta allows me to do this. However, it closes both of the curves in the process, meaning that you have to break each curve in two places and discard the joining segment to get back to the shape that you started with; if you're going to do that, you might as well break and rejoin the original curves manually.

[MEB]

That's why i said you can't perform boolean operations with open paths. Affinity will close them before attempting to perform the boolean operation which is not what a user expects when he wants to use a line to break a shape (like for example Xara does).

[Kuttyjoe]

In Illustrator there's a function called Trim.  If there's a shape overlapping another, trim will remove completely the portion of the bottom shape which underneath the upper shape.  This feature is missing from the geometry options.  Is there a way to achieve this in Designer?  It's a critical feature for my work flow.

[Alfred]

Perhaps you shouldn't be able to 'divide' two (intersecting) unclosed curves, but I find that AD on Windows beta allows me to do this. However, it closes both of the curves in the process, meaning that you have to break each curve in two places and discard the joining segment to get back to the shape that you started with; if you're going to do that, you might as well break and rejoin the original curves manually.

 

 

That's why i said you can't perform boolean operations with open paths. Affinity will close them before attempting to perform the boolean operation which is not what a user expects when he wants to use a line to break a shape (like for example Xara does).

 

Thanks, Miguel. When I said that AD "allows me to do this", what I meant is that other software such as Serif DrawPlus simply greys out the Boolean commands when you select open paths, but AD doesn't.

[gdenby]

In Illustrator there's a function called Trim.  If there's a shape overlapping another, trim will remove completely the portion of the bottom shape which underneath the upper shape.  This feature is missing from the geometry options.  Is there a way to achieve this in Designer?  It's a critical feature for my work flow.

 

My recollection from using AI years ago is that the AD "subtract" does the same thing as "trim".

[MikeW]

Thanks, Miguel. When I said that AD "allows me to do this", what I meant is that other software such as Serif DrawPlus simply greys out the Boolean commands when you select open paths, but AD doesn't.

 

And other software simply does it and does so properly. AD also needs to be able to do this properly.

[Kuttyjoe]

My recollection from using AI years ago is that the AD "subtract" does the same thing as "trim".

 

It's not the same. Subtract removes everything except a portion of the bottom most shape.  Trim leaves the visible portion of every shape, but removes all portions that are are underneath other shapes.  Visually, it's the same as what you started with.  But when you pull it apart, there's nothing underneath anything.  The closest function in AD is Divide, but divide chops up the parts into many smaller portions.  Illustrator has that function as well.