Boolean By Plane


Instructions

On the Design menu, point to Polygon Edit, then click Boolean By Plane to display the following panel.

Boolean Options

There are four boolean operations: union, intersection, difference and exclusive-or. Using the two polygons illustrated below, subject and clip, the results of each boolean type are shown.

Union (OR)

Regions where either subject OR clip polygons (or both) are filled.

Intersection (AND)

Regions where both the subject AND clip polygons are filled.

Difference (NOT)

Regions where subject polygons are filled EXCEPT where clip polygons are filled.

Exclusive-or (XOR)

Regions where EITHER subject or clip polygons are filled BUT NOT the area defined by both.

Use advanced options

The winding number of a region within a polygon is the number of times an infinite ray cast in any direction intersects the curve. Downwards intersections decrease the winding number, Upwards intersections increase the winding number.

  • Negative - Regions with winding number < 0 are filled.
  • Positive - Regions with winding number > 0 are filled.
  • Even odd - Regions with Odd winding number are filled, Regions with even winding number are not filled.
  • Non zero - Any non-zero subregion is filled.

The output can be made 'simple' or 'strictly simple'. A Strictly simple polygon does not have any shared points.

Level definition

With the option for Use tolerance, all polygons on the same plane (parallel to the defined starting plane), within the tolerance, will be grouped together.  With Use step size, each polygon will be grouped to the nearest plane N step sizes from the defined starting plane.

The default Plane method is Level (by z value). In all cases, the plane is determined by the first point of the polygon. To change from the default, select from the drop-down list to define a plane with the selected method. See below for explanations of the available plane methods.

To create a copy of a polygon, follow these steps:

  1. Click Create copy.

  1. Choosing a destination. You have three choices: the same layer, another existing layer, or a new layer.
    • Same layer: Select the option to save it to the same layer by clicking Same layer.
    • An existing layer: Leave the option Same layer unchecked. Use the drop-down list to select another existing layer the object will be copied to.
    • A new layer: Leave the option Same layer unchecked. Type a new layer name into the Layer name textbox.
  1. Click the Select button, then select the object(s) you want to copy.
  2. Click Cancel on the context menu, or right-click anywhere in the Vulcan workspace to exit the Select mode and return to the Filter panel.
  3. Click the Save button.

Important:   Be sure to save the changes to your Workbench session. If you do not save the changes any edits will be lost.