Trouble with Pro-booleans

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

THREAD CLOSED
 
Thread Tools Search this Thread Display Modes
  10 October 2012
Trouble with Pro-booleans

I try to avoid pro-booleans in general, but when I do use them, the object I select ends up deleting the object I am trying to indent, and becomes the new selected object.


This is obviously not the point of Pro-booleans. I noticed when I was first using pro-booleans this was likely because I was merely creating a shape with splines and then turning it into a poly and then extruding it, and then trying to use it to indent a shape into a more complicated poly.

Even when using conventional shapes however, I am still getting unexpected results where the object intended to be used as a way to create an indentation ends up deleting the other object and becoming the de-facto poly.


Is there a setting that needs to be turned on or off somewhere?
 
  10 October 2012
In order for pro booleans to work correctly you need to make sure both objects are clean, water-tight, and that there isn't any non planar polygons. I've been using pro-booleans for years on very complex geometry without any issue.
 
  10 October 2012
thanks for the response! What do you mean by non-planar polygons? You mean polygons jutting out from a poly?

I think this is something I am fundamentally missing.
 
  10 October 2012
All the polygons that make up your object represent a flat surface. It takes many polygons to create a rounded surface, like a cylinder for example, but each individual polygon is flat.

When you have polygon made up of more than 3 vertices, there is a chance that the polygon a become non-planar, meaning all the vertices are not lying on the same flat surface. When this happens, tools like booleans cannot determine how to cut up that surface.

The way you fix a non planar polygon is to subdivide it, using the cut tool, or flatten it, by selecting the polygon and scaling it on its local z axis to 0. This will have the side effect of shifting the vertices depending on how distorted the polygon is.

Hope this helps.
 
  10 October 2012
I haven't had that type of issue with polygons, but usually when your object gets deleted it's because you don't have enough polygons in that area of the print.

Also look into what mode you are using, if you just need to cut out a design onto a surface that you would then extrude you can do the Intersection>Imprint option rather than doing Subtraction. Sometimes you will find that Subtraction will cause problems like the object disappearing where the other option does not.

Also some tips---on your main object, make sure to remove any elements that are separate from the surface, a Union operation will be applied to that object before you do anything so if you don't want them attached then they need to be taken out before you do Booleans.
Also, at the bottom of the Booleans options is an option to remove edges that it doesn't feel like you need for your mesh, I always turn that off.
__________________
The Z-Axis
 
  10 October 2012
I tried creating as normal a polygon I could for the shape I wish to "carve" into the polygons I have currently.

I took screencaps so you could see my methodology:
http://i207.photobucket.com/albums/...proboolean1.png

Part 1: align the "carving" shape into the poly I wish to carve into

http://i207.photobucket.com/albums/...proboolean2.png

Part 2: the result deletes a good chunk of the mesh
 
  10 October 2012
You don't need Booleans for that, you can just select that surface and do and Inset and then extrude back
__________________
The Z-Axis
 
  10 October 2012
Yup, I realized that after I wrote that post. What do you think was causing the problem though? Not enough geometry?
 
  10 October 2012
It might be confusion with the separate parts, it looks like the part you were trying to subtract from was an individual piece within the big part, since it does Union to your original piece then it's possible that those pieces together didn't have enough polygons and couldn't Union correctly. That's why it's best to separate out the element you're trying to boolean from so it doesn't Union the parts.
__________________
The Z-Axis
 
  10 October 2012
Thread automatically closed

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.
__________________
CGTalk Policy/Legalities
Note that as CGTalk Members, you agree to the terms and conditions of using this website.
 
Thread Closed share thread



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 01:16 AM.


Powered by vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.