4.4. Regions

The Regions pane defines spatial regions (points, lines, planes, boxes, or STLs) of the geometry that are used for:

• Initial conditions

• Boundary conditions

• Point sources

• Internal surfaces

• Monitors

• Outputs

The following buttons are at the top of the Regions pane:

Icon	Description
	create a new region
	delete the selected region
	duplicate the selected region
	create a region that encompasses the entire domain
	create a region on the left side of the domain
	create a region on the right side of the domain
	create a region on the top side of the domain
	create a region on the bottom side of the domain
	create a region on the front side of the domain
	create a region on the back side of the domain

The (Add) button creates a new region. The region will be created with a generic name such as R_1; it is strongly recommended to rename the region to something more descriptive, so that it is easier to refer to it later. The Color button will change the color of the region in the model setup view.

The table created with the “From” and “To” fields for the X, Y, and Z axes define the extents of the region. These widgets take special parameters, min and max, that reference the minimum and maximum values of the domain, as specified in the geometry section. These values will get automatically updated when the extents in the geometry section are updated. The region type will be inferred from the specified extents.

If the region needs to be a collection of triangles from the STL file, select the ‘Select facets’ (STL) checkbox. The selection shape can be changed between a box and an ellipsoid. Triangles that fall on the edge of the shape can be sliced by selecting the ‘Slice facets’ checkbox. The triangles can be further filtered by the normal direction by specifying a vector and a deviation angle around that vector.

Hint

If a region is referenced by an item in the Used by column, the region can not be deleted and its type (STL vs non-STL) cannot be changed.