Boolean Improvement


I would like to see if I can request for developers to make a small improvement on how Boolean work. The system of Boolean is flawed. I’ll provide a good example.

(LEFT PICTURE) You can see there’s no problem at all. BUT what if I change the height of face @ top and bottom to be at the same height as the other cube is. I remove half of the cube, so you can see it clearly. A full cube is a lot messy. This is what happened:

(MIDDLE PICTURE) So the result of using Boolean (UNION) is what it looks like. It is quite a mess and this shouldn’t be the case.

(RIGHT SIDE) the result should look like this:

As you can see the issue is when there are more than 1 objects that have the same height where the boolean would be useless and it doesn’t remove the unnecessary faces and edges. The result is a little different in 2.79 and 2.80… but It’s still a mess in the end.
I hope this will help developers make some improvement in the future. Thank you for taking the time reading this topic.

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I am working on Boolean, trying to fix cases like this as one of the main goals.


Ah. that’s good to know. Good luck :+1:

this is great news! …and also obvious that sooner or later the god of the Bevel tool would embrace the Boolean tools ^____^
soo … I’m sure you already know what to do, but since I don’t know how to do anything else, let me show you moments of inspiration on Booleans.
I did the wordplay :joy:

hahaha. That’s a good video. The video is quite very clear on how to use boolean system. It really give me a clear understand of how the boolean system (difference) basically work. :+1:

we’ll have to wait until the day that the boolean system in Blender will become so much better ^_^.

to be honest, I can’t wait for that day and the day for an official release of Blender 2.8 :wink:


Oh I don’t realize that “Moments of Inspiration” is actually a software… I was wondering what is the name of that program you used for a while. “MoI”… hmmm That system look very good… but that’s not only the system. I have used one different 3D software and I did some test on the system of Boolean. it’s a lot powerful and flawless. :thinking:

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yes moi 3d is totally another software …
it is dedicated only to cad modeling, it was created by the same author of rhinoceros … and it is hard to believe that it has such a simple and minimal interface and at the same time manages to be very powerful in its field …
I try to suggest it as a “moment of inspiration” often to blender developers … because it is objectively done well … and I would love to see similar tools in blender … coincidentally blender lacks just those functions where moi excels … almost like if they completed each other …

how is compatibility of models between Blender and MOI? I am talking about where you import the model from MOI to Blender.

exporting in obj or stl is good

blender has no good nurbs …
otherwise the ideal would be to export in step format from moi

I don’t know if there is any addon that reads the step format for blender, I think I saw it for “mechanical blender” … but I never tried it

I see… hmm I’ll try MOI someday out. thanks and it was a good discussion.

Are there any plans at all to have booleans automatically create vertex groups of newly created vertices for modifiers lower in the stack to use? (I’m thinking for bevel and the new triangulate modifier.)

I would like to enable things like bevel-after-boolean somehow, eventually. And the ability to flexibly specify what/how triangulation happens afterwards also seems useful. Whether it be by creating vertex groups or some other method – who knows at this point. First order of business is to get Boolean working reliably and well even, especially as regard to coplanar etc geometry.


Thanks for your work, at this moment its give big improve. Testing modifiers in 2.8 -subd, booleans, new bevel and triangulation modifier

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i was just using Blender 2.8 to work on a vehicle. I was creating a fan for the vehicle. I ran in some issue. I’m not sure if it’s a bug or not. So I ran some test. There are 2 objects. I move the main object with boolean modifier up and down to see if the issue is gone. BUT the issue is not resolved.
The shadow you see is at everywhere. I believe it’s a bug. here’s the picture for you to take a look at.

The boolean modifier is “UNION”

Another bug with beveling (CTRL + B). If this was reported, then great. If not.
Here’s a picture:

For your information, sorry about the second post since I cannot post 2 pictures in the same post. There’s nothing I can do about that.

Thanks @Howard_Trickey for your efforts here. I just wanted to add a little to the understanding. Many years ago I worked on a facet modeller similar in representation to Blender. I wrote the code for the Boolean ops. Clean intersections of surfaces which had nice curves of intersection were straightforward and done quite quickly. However, coplanar faces, colinear edges and touching vertices were a big problem. After three years these were not completely resolved. Humans can look at a scene and say how they’d expect the result to look but software has a harder time. Sometimes (in my code) combining clean manifold objects created non-manifold results and that’s no good. We had a thing called “the epsilon factor” where we nudged vertices in different directions to see how the result might change sometimes this improved the result other times it didn’t. A lot of modern software still doesn’t evaluate Boolean operations correctly in all cases. I’m saying all this so that people get a sense of how hard this task is and don’t underestimate the effort required to solve it.

Oh that’s a new information. I had no idea the level of difficult it is. I knew it was that hard… but not that bad. :thinking:

interesting. thanks for sharing. I thought other 3D softwares have a good or perfect system of boolean. but It doesn’t seem to be the case.

Thanks PaulMcManus for explaining to others why they should not expect a quick fix on this. I’ve been working for months on it already (spare time).

Xelbayria - that bevel result is unrelated to Boolean, right? You can report it as a bug (see help menu in Blender). But first check if normals are OK. I suspect that’s the problem.


Yeah the normal are just fine. I checked. and I’ll report it as a bug.

EDIT 1: Yes the beveling is unrelated to boolean. I am not sure why it show the result of that issue. and It’s still an issue.

If add mark bevel for boolean modifier, its give dynamic booleans with bevel, like bevel after boolean, but dynamic

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Is there a way to alt d a Boolean object without losing the modifier parameter ?