Boolean modifier inverts Difference and Union (sometimes + strange behavior)
Closed, ResolvedPublic

Description

System Information
Windows 10 64 bits
The issue is not with the rendering but just in case: Iris Pro graphics with Nvidia 960M

Blender Version
Broken: 2.78c e92f235283

Short description of error
Sometimes when applying the boolean modifier, selecting Difference does a Union and conversly.

Exact steps for others to reproduce the error

  • Open attached Blender file

  • Select Primary white bishop
  • Add Boolean Modifier (Difference, BMesh, Object: Cube)
  • Apply

At this point a Union was made instead of a Difference. If selecting Union it makes a Difference instead.

EDIT: when doing a Difference by selecting Union, faces to "cover the holes" are not created like they're supposed to be

It seems like deleting the cube and trying with a fresh one corrects the error.

Maverick Chardet (chardetm) renamed this task from Boolean modifier inverts Difference and Union to Boolean modifier inverts Difference and Union (sometimes + strange behavior).Mar 29 2017, 12:23 AM
Maverick Chardet (chardetm) updated the task description. (Show Details)
Aaron Carlisle (Blendify) triaged this task as Incomplete priority.Apr 15 2017, 10:55 PM

I think you uploaded the wrong blend-file.

I think you uploaded the wrong blend-file.

Yes you're right sorry, I just changed the file, this one is the correct one.

Aaron Carlisle (Blendify) raised the priority of this task from Incomplete to Needs Triage.Apr 16 2017, 6:31 PM

I confirm all of this, even the "holes not covered" part, using the supplied test case.

also with this test case, the "Carve" solver is confused:

intersect --> difference
difference --> intersect
union --> cube - bishop

I recommend turning off viewport visibility for "Cube", so you can see what's going on.