Boolean UnionΒΆ

Learning targets

  • Construct object by Boolean operation (union)

  • Apply shape transformations (normal displacement, corner rounding)

This example constructs a binary mask like square object with serifs at its corner. We apply corner roundings in the horizontal directions. Normal displacements are used to define oblique sidewall angles in z-direction.

_images/ex3d_boolean_union_mesh.png

.jcm Input File

  • layout.jcm [ASCII]

      1Layout3D { 
  2  
  3  UnitOfLength = 1e-09 
  4  MeshOptions {
  5    MaximumSideLength = 20
  6  }
  7  Extrusion {
  8    Objects {
  9      Parallelogram {
 10        DomainId = 1
 11        Priority = -1
 12        Width = 200
 13        Height = 200
 14        Boundary {
 15          Class = Periodic
 16        }
 17      }
 18      
 19      
 20      BooleanOperation {
 21        DomainId = 2
 22        Operator = Union
 23        
 24        A {
 25          Parallelogram { 
 26            Height = 80
 27            Width = 80
 28          }
 29        }
 30        
 31        B { 
 32          Parallelogram {
 33            Height = 32
 34            Width = 32
 35            GlobalPosition = [-40 -40]
 36          }
 37          Parallelogram {
 38            Height = 32
 39            Width = 32
 40            GlobalPosition = [40 -40]
 41          }
 42          Parallelogram {
 43            Height = 32
 44            Width = 32
 45            GlobalPosition = [40 40]
 46          }
 47          Parallelogram {
 48            Height = 32
 49            Width = 32
 50            GlobalPosition = [-40 40]
 51          }
 52        }
 53        
 54        NormalDisplacement = 0        
 55        CornerRounding {
 56          Radius = 4
 57          NPoints = 5
 58        }
 59        
 60      } 
 61    }
 62    MultiLayer {
 63      MeshOptions {
 64        MaximumSideLengthZ = 20
 65      }
 66      
 67      LayerInterface {
 68        BoundaryClass = Transparent
 69      }
 70      
 71      Layer {
 72        Thickness = 50
 73        DomainId = 1
 74      }
 75      
 76      LayerInterface {
 77        GeometryValues = [
 78        BooleanOperation{1}/NormalDisplacement = -3
 79        ]
 80      }
 81      
 82      Layer {
 83        Thickness = 65
 84        DomainIdMapping = [1 2 2 3]
 85      }
 86      
 87      LayerInterface {
 88        GeometryValues = [
 89        BooleanOperation{1}/NormalDisplacement = 3
 90        ]
 91      }
 92      
 93      Layer {
 94        Thickness = 50
 95        DomainId = 4
 96      }
 97      
 98      
 99    }
100    
101  } 
102}

Note

The mesh is constructed in a tensor-grid like manner (horizontal xy-mesh \times vertical z-mesh). When deforming in z-direction, the mesh quality depends on the cross-section mesh. For this we have chosen a zero normal displacement. This way the cross-section mesh corresponds to the geometry in middle for the structure.