Copy is a general function that allows you to select a group of entities and copy them with a movement operation performed, either translation, rotation, mirror, scale or offset.

Select the type of entities to copy. In geometry mode choose between point, line, surface and volume; in mesh mode choose between nodes and elements. All the lower entities belonging to the selected one will automatically be computed. Next, the type of movement needs to be chosen and its parameters defined. The options are:

• Rotation: It is necessary to enter two points in 3D, or one point in 2D. These two points define the axis of rotation and its orientation. In 2D, the axis goes from the defined point towards z positive. Enter the angle of rotation in degrees; it can be positive or negative. The direction is defined by the right hand rule. In 2D, the direction is counter-clockwise.
• Translation: Two points are defined. Relative movements can be obtained by defining the first point as 0,0,0 and considering the second point as the translation vector (see Point definition).
• Mirror: Three points are defined (they cannot be in a line). These points form the mirror plane. In 2D, the mirror line is defined by two points.
• Scale: This is defined by a center and a point. Every coordinate of the point is the scale factor for every x,y,z axis. A scale factor greater than one increases the size, while a scale factor less than one decreases the size. It may also be negative, changing the sign of the corresponding coordinates.
• Offset: This is defined by one positive or negative scalar magnitude. Each entity will be moved in the direction of its normal, by the magnitude given. In 2D, the normal is considered to lie in the plane z=0. This option works either for lines, surfaces or mesh elements.
• Sweep: This is an option for copying figures along a line (path line). You can simply copy the figures (and then specify a number of copies) or extrude them. Both methods have basically the same options.

The 'end scale' factor determines how the figure is scaled along the path curve (the scale value starts at 1.0 and varies in a linear way until the 'end scale' value). This scale value must be greater than zero.The extrusion (and the copy) always starts on the start point of the path line. If you select 'twist mode' as on, then the relative position of the figure to copy with respect to the start of the path line is conserved along the line.

In a non-planar curve, there is not only curvature, but also torsion. This may cause some unexpected behaviour, because the figure also has a rotation along the tangent direction of the path:

Next the 'XY plane' option is used, which makes certain that the initial vector will remain in this plane during extrusion. (In this example, the axis is Z).

The option 'ByDer2' uses the second derivate of the path line as a normal to the plane in which that initial vector has to remain. A rotation along the path line can be forced using the 'Angle' parameter (degrees):

Finally, if the path line is a polyline, then the extrusion will be divided into several parts:

• Align: This is an option to move figures from a generic position to the desired one. Set the new location specifying three source points and three destination points: the first point defines the exact destination of the source point; the second point is not necessarily the exact destination, but a point over the destination straight line; the third point is not necessarily the exact destination, but a point over the destination plane

Other available options are:

• Collapse: If this option is set and after the copy operation an entity occupies the same position as an existing one that does not belong to a frozen layer, both entities are converted into one.
• Do Extrude: This option can be set to either lines, surfaces or volumes. When a movement is selected, the copy is made and lines connecting the old and new points are created. These lines will either be straight lines or arcs depending on the movement type. If extrude surface is chosen, NURBS surfaces connecting old and new lines will also be created. If Volumes is chosen, the volume contained between old and new surfaces is also created. This option is not allowed when copying volumes.
• Create contacts: Creates separated contact volumes (see Contact) for every copied surface. This option is only available when copying surfaces.
• Maintain layers: If this option is not set the new entities created will be placed in the layer to use; otherwise, the new entities are copied to the same layers as their originals.
• Multiple copies: By selecting this option and giving the number of repetitions, the selected operation is performed this number of times. This option is not available for mirror.

Note: Entities belonging to a frozen layer (see Layers and groups (only Preprocessing)), are not checked when sharing old entities.