Operating system: Windows 10 Home
Graphics card: GTX 1060
Broken: 2.82
Boolean Union = Booleanis treated as Difference and vice versa when a mesh is generated with mirror modifier.
Steps to reproduce:
1. Create a cubeGet any mesh, use it as a boolean object (the 'cutter' object) on any mesh Ma cube to carve a piece of geometry out using Boolean modifer set to 'Operation' to Difference.
2. Duplicate it, move the duplicate to another part of M and set up the boolean same as the cube1.
3. Now go back to cube1 and apply its location, add a mirror modifier and mirror that baby over the xAdd a mirror modifier to the cube and mirror it over X axis. (handedness change somehow?)
- 3a. Note: Pretty sure I saw the following behavior before applying mirror modifier to cube 1 but I'll write out what I did anyway.
4. Apply mirror modifier, go into edit mode, press P -> separate by loose parts. Apply location for cube3 and move it to the same location as cube 2. Rotate cube3 to adjust for difference in rotation caused by the mirror.
Result: You will see that the mirrored portion of the mesh does not boolean properly.
More Evidence:
4. Apply mirror modifier, separate the meshes.
5. Try to boolean cube3 into M the same was asnew cube1 and cube2 into your mesh. You can'twill see that you cannot use Difference as a cutout now, you have to use Union.
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