# Boolean Operation Window

The Boolean Operation Window is a dockable window that allows you to combine two mesh objects into a single object. Open the Boolean Operation Window by selecting "Model | Boolean Operation..." The supported operations are listed below.

- Fuse -- Combine overlapping meshes, any triangles that intersect will be split so that the meshes share vertices along the edges where they intersect. No faces are removed by the Fuse operation.
- Union -- Combine overlapping meshes like the Fuse operation, then removes internal faces (faces inside the volume of either enclosed mesh.
- Subtraction -- Removes the selected mesh and any part of Object A that is inside the volume of the selected mesh.
- Intersection -- Removes any volume inside of Object A or the current selected mesh that is not contained within both objects

Select Object A | Select Object B
Fuse | Union
Subtraction | Intersection

For the union, intersection, and subtraction operations to work properly, all meshes involved must be enclosed (otherwise the behavior of the face-removal step is undefined). If the meshes are not enclosed you can still use the fuse operation and manually remove the faces that must be removed.

To peform a boolean operation, select an enclosed mesh and then click Set Object A. Then select another enclosed mesh and click [op] With Selected where [op] is the name of the selected operation (the button name changes when you select an operation).

After using a boolean operation you may want to use Simplify Mesh to combine some newly created faces.