Two kinds of geometries can be defined in inside the MSC Apex Generative Design Configuration File - spaces Spaces and masksMasks.
The main difference between these two types of geometry definition is that only the Design Space is categorized as a spaceSpace. A Because a space get gets the additional information regarding the material of the geometry. Whereas masks Masks are just marking areas in the part Design Space such as Non-Design Spaces, Constraints, Forces etc. by adding attributes explained below. For every creation of a Non-Design Space or other another boundary condition a new Mask is being created. However, if you simultaneously select multiple cells in the Non-Design Space Constraints Tool and then create the Non-Design Space one all cells are saved in just one Mask. This creation and handling of the Masks is very important for the Keep Non-Design Spaces Function. You can find more information on how to apply loads and boundary conditions for this function here.
To get a good understanding of the difference the example of the Bookshelf Tutorial is used.
Example: Generative Design - Bookshelf
The Bookshelf is a beginner tutorial with just a few Non-Design Spaces and Boundary boundary conditions thus . Thus, it is a great example to explain and to have a look at the different geometries.
It has one Design Space, four Non-Design Spaces, one Mask representing the force application area and three Masks representing the fixation application area. The Space and Masks are marked in the picture below.
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The input in the Configuration File looks as follows:
#=================Geometry=====================================
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Space Bookshelf
.path = Bookshelf.stl
.material = 316L
.E-Modul = 192372000000.000000
.Poisson = 0.300000
.density = 7.970000e+03
...
Mask Force_-Moment_1
.path = Force_-Moment_1.stl
Mask.Force_-Moment_1.nonDesign
Mask.Force_-_Moment_1.preserve
Constraint application regions
Mask Constraint_1
.path = Constraint_1.stl
Mask.Constraint_1.nonDesign
Mask.Constraint_1.preserve
Mask Constraint_2
.path = Constraint_2.stl
Mask.Constraint_2.nonDesign
Mask.Constraint_2.preserve
Mask Constraint_3
.path = Constraint_3.stl
Mask.Constraint_3.nonDesign
Mask.Constraint_3.preserve
...