COMSOL 6.2 - Transform

) attribute to position, rotate, or scale an imported mesh. The positioning is done by specifying a point in the source and a position to match with the point. After that, any specified rotation or scaling is applied, and, lastly, if an additional displacement is specified, it is added to the translation. With the default settings, the imported mesh is not transformed.

Figure 8-109: Mirroring the mesh of a head and torso in the xy-plane using a Transform attribute.


	Transform is an attribute that acts on the Import node only.


	No associativity update is done for geometric entity numbers. It is recommended to add Transform attributes directly, before adding more operations to the meshing sequence.

To add a attribute, right-click the node and select (

). Then use the sections below to specify the displacement, rotation angle, and scale factor for the transformation.

Position in Source

Control how the imported mesh is positioned relative to the coordinates in the file by matching a predefined point in the file with the position specified in the section. From the list choose:

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(default) to position the origin in the file.

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to position the minimum coordinate of the imported mesh’s bounding box.

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to position the center of the imported mesh’s bounding box.

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to position the center in x and y, but minimum z-coordinate of the imported mesh’s bounding box. For 2D: position the center in the x-coordinate and minimum in the y-coordinate of the imported mesh’s bounding box.

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to position the center in x and y, maximum in z-coordinate of the imported mesh’s bounding box. For 2D: position the center in the x-coordinate and maximum in the y-coordinate of the imported mesh’s bounding box.

Position to Match

Control if the imported mesh is positioned relative to the origin or to a specified existing vertex. Specify the point as (default) or . For the option , specify a mesh vertex in the associated section. The mesh is translated so that the specified point is moved to the position to match.

Displacement

Offset the imported mesh by entering , , and (3D) values for the displacement. The displacement is applied after the and points have been matched.


	The positioning of imported meshes is supported for static positioning only. To parameterize the geometry and move objects around in a parametric sweep, use the option of Creating Geometry from Mesh to apply the parameterization in the geometry sequence.

Axis (3D only)

The mesh is rotated so that the z-axis in the source mesh is rotated to the specified axis. Any specified rotation is performed around this axis (after the z-axis has been rotated to match this axis). Select as (default), , , , or .

Rotation Angle

Specify a rotation of the mesh around the origin (as specified by the point, but before the offset or translation to the anchor vertex is applied). If you want another center of rotation, you can use several attributes in a sequence to first move the rotation center to the origin and then move it back.

Scale

Scale the mesh with an isotropic or anisotropic scale. Select (default) or from the list and enter values for the scaling. Enter a negative scale to mirror the mesh. The scale is applied prior to any translation or rotation; the point specified in is used as center point.


	Using an anisotropic scaling with zero scale effectively projects the mesh onto a coordinate plane. In general, this leads to degenerated elements and self-intersections, but it is a useful way to project a curved surface mesh onto a plane.


	Importing Meshes

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See STL Import 2 — Remeshing an Imported Mesh:
Application Library path .

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See Head and Torso HRTF Computation:
Application Library path .