Creating Chain Extrude Objects

The Chain Extrude tool automatically creates extruded objects with both continuous and repetitive elements. Architectural features such as an awning contain a continuous element (the awning) and intermittently repetitive elements (the supports). By specifying the polygon or polylines to be extruded, and then indicating the path of the extrusion, the object(s) are automatically extruded along the path.

Creating the Profile Objects

The profile objects determine the shape of the chain extrude object. The profile objects can consist of up to three polygons/polylines or up to two polygons/polylines and one locus. For Architect and Landmark users, profile objects are contained in the [VectorWorks]\Libraries\Objects-Imperial\10_Wall Accessories.vwx file.

To create the profile objects:

1.	Create the continuous shape first. The Chain Extrude tool considers the first, or back, polygon/polyline to be the continuous shape, and extrudes it along the path polygon.

2.	Create the second shape; the front object is considered to be the repeating or intermittent object.

A second shape is not required.

The reference location of the chain extrude relative to the path is the upper right or lower right corner of the shape’s bounding box. This location can be changed by including a locus in the profile group. The locus becomes the reference point for the path polygon in the profile group. This is useful if the bounding box of the repeating shape extends beyond the bounding box of the continuous shape.

3.	Apply fill colors to the profile objects through the Attributes palette. The colors are applied to the continuous and repeating shapes in 3D.

Creating the Chain Extrude Object

Once the continuous and, if any, repeating shapes have been defined, specify the path for the chain extrude with the Chain Extrude tool.

 

To create the chain extrude object:

1.	In Top/Plan view, select the continuous and, if any, repeating shapes.

2.	Click the Chain Extrude tool from the Building Shell tool set.

3.	Draw the chain extrude path polyline.

4.	The chain extrude object is created based on the path drawn.

Chain Extrude Properties

The chain extrude object parameters can be edited in the Object Info palette.

 

Parameter	Description
Draw 3D	Select to display the chain extrude object in 3D view; deselect to display the object only in 2D view
Flip	Select to flip the orientation of the chain extrude object (for example, toward the inside of a room for a crown molding, instead of the outside of a building for a cornice)
Center Ribs	Select to draw the repeating element centered along the edges of the path
Corner Ribs	Select to draw the repeating element at the corners of the path
Vertical Datum	Specifies the reference point for the chain extrude object
Thickness	Specifies the thickness of the repeating elements of the object
Spacing	Indicates the spacing distance between the repeating elements of the object
Polyline parameters	Edits the chain extrude path polyline. See Reshaping Objects

The placement of the repeating elements of the chain extrude object depends on the path created by the Chain Extrude tool. In particular, special considerations apply to the “miter zones” at the corners of the path:

No repeating elements perpendicular to the building face will be drawn in miter zones

The miter zones are excluded from the length calculations of the sides (for spacing calculations, for example)

Repeating elements at corners, if drawn, bisect the angle of the corner and are elongated accordingly

The chain extrude path can be reshaped with the 2D Reshape tool to add, subtract, and change vertices. The continuous and repetitive elements are automatically adjusted to fit the new shape. The path polyline can be edited by selecting Modify > Edit Group, and selecting Path, or Edit or Edit Path from the context menu (see Editing a Group).