Fail: Boolean Divide Shapes With Tangents

[affinitydemoguy]

Hello everyone!

(I am new here, so pardon me if I posted my issue in the wrong category.)

I've been playing around with Affinity Designer on and off for the past year and a half. I really want to fully transition to Designer (coming from Illustrator), but I keep bumping into the same little annoying issues that would make my workflow painfully slow.

One issue in particular has to do with the Boolean operations. I've seen this question raised a few times on the forum before, but no solution so far. Will there ever be?

 

The problem

It appears that the Boolean Divide action doesn't work well with shapes that have one or more overlapping edges. The result is a big mess. You either get the compound shape partially divided or not at all. Then you would also get those pesky thin "hair" lines coming out parts of the resulted group. Artifacts... artifacts everywhere!

Anyone can replicate this issue in a matter of seconds with basic shapes. Create a square and a circle of the same size. Apply different fills. Align them to the center of the spread and make sure that the square is behind the circle in order to see the individual pieces better. Divide both shapes using the Boolean actions panel.

Normally you should have the four corners of the square that are seen outside the circle cut into separate pieces. The result would be 5 shapes in total (including the ellipse in the center). However, Affinity Designer has something else in mind (see images below).

I have given up hope that they will fix this bug. Therefore, can anyone suggest an alternative work-around method for this issue instead?

Thanks in advance!

[PixelPest]

When there´s not the slightest overlapping no "cutting" will happen.

Here´s to an easier more robust/reliable way:

And here´s a quicker way with 2 squares:

1. draw square

2. double and  round corners - bake corners

3. select both and call Boolean subtract then Divide right after - 4 corner parts:

Cheers

[affinitydemoguy]

23 minutes ago, PixelPest said:

When there´s not the slightest overlapping no "cutting" will happen.

Here´s to an easier more robust/reliable way:

Cheers

Thanks for the tip! That's an interesting approach. But what if the shapes are more complex, as is often the case?

Also, in my example both shapes had identical dimensions (300 * 300 px). They were both centered vertically and horizontally. In theory the circle should be touching the four edges of the square. And thus the ellipse should have cut the square in 4 pieces (exactly where their edges touch). But that's not what happens.

Even as seen in your video example, when you align the square to the circle, the indicators show that the selected object snaps on all four sides. And yet Boolean > Divide won't cut the corners of the square. I don't understand why.

[AffinityFran]

I think the problem is more general with inaccuracies with the boolean operations. I'm only a light user of Designer but have discovered these problems myself recently and by chance decided to have a look on here for answers this morning.  Whilst PixelPest's answer solves this specific shape issue, more complex shapes exhibit similar problems and can't be solved this way.  If you look at the attached Designer file as an example (I'm not looking for a solution to this specific shape problem) even what should be relatively straightforward operations fail miserably, and it gets even messier with much more complex shapes.

I'm assuming this is a bug.  I don't remember having this simple problem in Illustrator.

Boolean Inaccuracies.afdesign

[Hilltop]

PixelPest, I reallly like how you think and how you've mastered these Boolean operations. 

[affinitydemoguy]

3 minutes ago, AffinityFran said:

I think the problem is more general with inaccuracies with the boolean operations. I'm only a light user of Designer but have discovered these problems myself recently and by chance decided to have a look on here for answers this morning.  Whilst PixelPest's answer solves this specific shape issue, more complex shapes exhibit similar problems and can't be solved this way.  If you look at the attached Designer file as an example (I'm not looking for a solution to this specific shape problem) even what should be relatively straightforward operations fail miserably, and it gets even messier with much more complex shapes.

I'm assuming this is a bug.  I don't remember having this simple problem in Illustrator.

Boolean Inaccuracies.afdesign

I agree with you.

And just to get it out there, I am not trying to belittle Affinity Designer in no way. But that should be a relatively straightforward operation as you said. It only takes one click to do this in Illustrator, and no matter the complexity of the shapes, one gets perfect results every time.

[PixelPest]

I don´t have the issue neither in Inkscape or Intaglio.

The underlying maths needs more love as stated and reviewed all over this forum.

Cheers