#Boolean in Editor
10 messages in this thread
I often get an error message when I am tryingto create some boolean operations.
It usually occurs when I am trying to cut a 3D object in half. It tells me to
"adjust the geometry". In just what way am I supposed to adjust/change the
objects to correctly make the operation work? -Scott
Hi Scott,
<< . In just what way am I supposed to adjust/change the objects to correctly
make the operation work? -Scott >>
object/tesselate is a good one to try first.
Check out page 7-55 of the reference manual.
– G
Ive had hit and miss experiences with boolians. Today I had some luck with
intersect in order to perform a subtraction that wouldnt work
with subtract. Must be an art rather than a science.
Ed
Thanks Gary, I'll do that. Just as the attached reply says, I have had to use
intersection to get subtraction, etc. at times. -Scott
Scott,
>>boolean, "adjust the geometry"
I am sorry to be so late in answering this, but…
When unable to complete a boolean there is one other VERY IMPORTANT
(in my opinion, anyway <g>) thing to do that I've haven't seen
written down – or if I have, my poor brain has forgotten where:
*** Don't try to boolean an object which is composed of two or
more elements which overlap in the area of the boolean.
Well, go ahead and try, but it may not work. <g>
If you manually overlap several objects then attach them, you will may well get
the dreaded "adjust the geometry" message.
For example, consider an object made of three overlapping sphere
elements, thru the middle of which you wish to bore a square hole by
subtracting a simple box. For me, this fails every time. The
solution: separate the object back into three spheres using
Create/Element/Detach, make two copies of the box object, then
subtract one copy from each sphere. Finally, reattach the three
resultant objects. For me, this works every time.
JKJ
JKJ,
>> *** Don't try to boolean an object which is composed of two or
more elements which overlap in the area of the boolean.
Well, go ahead and try, but it may not work. <g> >>
Absolutely right. I think it also applies to multiple booleans as
well as attached elements. I just did a bool with one central object
and two mirrored objects left and right. Left and right needed to
smooth together below the centre so I made them overlap slightly.
Left bool'd with centre ok but right would not bool with the new
object. Move left and right apart – just more than the weld threshold
– no problem but you have to manual weld.
I notice that if you subtract a hole through a multiple bool'd object,
even if it works you can get a lot of stray vertices left around.
Another thing is that bool'd objects can have faces that are d****d
difficult to smooth. Ed asks, "Art or science?" Both, and I too have
noticed you sometimes have to invert the commands to get what you
want!
Keeps us awake.
John
Thanks guys! The oject I am having problems with was made by attaching
3 different objects! When I separated them again, the boolean worked
just fine. Thanks for the info! -Scott
Glad it helped, Scott!
In the case of a boolean failure on multiple overlapping elements, there is one
other thing you can do that I forgot to mention:
Instead of building a composite object by _attaching_, combine the components
using the boolean Union. This will leave the object with a single surface
instead of overlapping elements surfaces. A subsequent subtraction will then
have no problem. (This method is actually less work than what I described
earlier – sorry I forgot to mention it)
I love the boolean improvements the Yosters put into R3 – MUCH improved from
R2. And that's no bool. <g>
JKJ
Thanks for the additional info. I'll give it a try once the current project is
done rendering in a day or so. -Scott