Creating a surface array

The Create Surface Array command duplicates 2D or 3D geometry onto a planar object or NURBS surface. This allows you to easily create free-form surfaces with geometric patterns, curtain walls, open framework, and more.

The following table describes the types of objects that can be used as array items, as well as the method used to project the objects onto the base surface.

1. Select a planar object or NURBS surface to be the base of the array object. Optionally, also select the 2D or 3D geometry that will be duplicated on that surface (alternatively, edit the surface array object after creation to add the array geometry).

Parameter	Description
Select a base surface object	If multiple objects were selected, by default, the largest object is highlighted in red, which indicates that it is selected to be used as the base surface. Click the Next or Prev button to highlight a different object. The buttons are grayed if only one object is selected.
Origin X’ Factor	Enter the X offset of the array pattern’s origin from the center of the base surface. The value must be a number between -1 and 1. For example, to shift each array item to the right by half of the item’s length along the X axis, enter 0.5.
Origin Y’ Factor	Enter the Y offset of the array pattern’s origin from the center of the base surface. The value must be a number between -1 and 1. For example, to shift each array item down by a quarter of the item’s length along the Y axis, enter -0.25.
Pattern Rotation	Enter a rotation angle for the array pattern
X and Y Repetition Parameters	For both the X and Y axes, specify how the array objects are to be repeated
Repetition Mode X’/Y’	Select whether to repeat array objects on the base surface based on a No. of Repetitions, or a Fixed Distance per object
No. of Repetitions X’/Y’	If Repetition Mode is set to Number of Repetitions, enter the number of times the array object is to be repeated along the X or Y axis. The array objects are resized as necessary to fit the base surface.
Fixed Distance X’/Y’	If Repetition Mode is set to Fixed Distance, enter the length of each array object along the X or Y axis. The number of array objects is adjusted as necessary to fit the base surface.
Offset X’/Y’ Factor	Enter a number to control the space between the array objects. The distance from the center of one array item to the center of the next item (in the same row or column) is the factor times the array item’s size. For example, if the array item is 12” total, and the Offset X’ Factor is 1.25, the distance from the center of one item to the next in the same row is 15” (12 x 1.25). If the offset factor is 1, the array items in that row or column touch each other; if the factor is negative, the array items overlap.
Shift X’/Y’ Factor	Enter a number to shift the position of the array objects from one row or column to the next. The distance from the center of one array item to the center of an array item in the next row or column is the factor times the array item’s size. For example, if the array item is 12” total, and the Shift Y’ Factor is 0.25, the distance from the center of one item to the center of the item to the right (in the next column) is 3” (12 x 0.25). If the shift factor is 0 (zero), the array items are aligned.
Edge Conditions	Specify how to handle array objects that extend beyond the boundary of the base surface: allow the objects to Overlap the edge, Omit those objects from the array, or Trim the objects at the boundary
Display Base Surface	Select whether to display or hide the base surface
Scale Z’ Value	When selected, the array objects are automatically scaled along the Z axis, proportional to how much the objects are scaled along the X and Y axes (to fit the base surface). When deselected, the array objects have the same Z value as the original array item.

Editing a surface array

After a surface array has been created, you can edit its properties from the Object Info palette. All of the parameters that are available during the array creation can be changed. You can also change which side of the base surface the array is applied to (Switch Z’ Direction).

You cannot edit the surface array geometry directly; use the Edit Surface Array command to edit the base surface and array components individually.

2.From the Choose component dialog box, select whether to edit the base surface or the array items.

Alternatively, right-click on the surface array and select Edit Base Surface or Edit Array Items from the context menu.

3.The Edit window displays the item to be edited. A colored border around the drawing window indicates the editing mode is active.

4.Reshape the geometry, change the attributes, and move, add, or remove items as needed. Keep in mind that only one item can serve as the base surface. Also, the base surface and array items must be one of the valid object types described in Creating a surface array.

5.Click the Exit button in the top right corner of the drawing window to return to regular drawing mode and update the surface array.

Command	Path
Create Surface Array	Model

Array item	Projection method
Solid Sweep Text	Project by center of bounding cube
Symbol instance	Project by symbol origin
2D/3D Locus Arc Bitmap Line Oval Polygon Polyline Rectangle Rounded rectangle	Project by object definition points (the result is always a planar object)
Extrude/multi-extrude	Project profile object by definition points
3D Poly Extrude along path Mesh NURBS curve NURBS surface	Project by each vertex (the result may not be planar)
Group	Project member objects as described above; all members of the group must be legal array objects

Command	Path
Edit Surface Array	Modify