Find Circles
Find Circles tool is used for extracting circular objects in horizontal section. It supports the digitization of objects such as pillars and pipes. It creates circular elements at the location of circles detected in the point cloud. The elements represent the fit circle.
Circle extraction is most reliable done in very dense point clouds collected with a tripod-mounted scanner or a mobile scanner system.
To find circles:
1. Select Find Circles tool.
This opens the Find Circles dialog:
2. Define settings and click OK.
This creates circular elements at the location of the tree trunk measurement. The elements are placed on the active level using the active symbology of the CAD file. They may be modified using CAD tools.
SETTING |
EFFECT |
|---|---|
From class |
Point class(es) from which to find the circles. |
|
Opens the Select classes dialog which contains the list of active classes in TerraScan. You can select multiple source classes from the list that are then used in the From class field. |
To class |
Target class into which points on detected circles are classified. |
Diameter |
Diameter range of the circles to be extracted. |
Tolerance |
Determines how much points are allowed to vary from circle shape. Should reflect measurement noise level and surface roughness of the circular objects to detect. |
Max inside |
Maximum ratio of points allowed inside circles compared to points detected on the circle surface. Smaller value helps to limit search to solid objects. |
Min coverage |
Determines how widely the circle perimeter should be covered by point observations. Bigger value helps to restrict the extraction to more reliable findings. Smaller value is required if objects are captured from one side only. |
Inside fence only |
If on, only points enclosed by the active fence or polygon extent are considered in circle extraction. |
Draw circles |
If on, the tool creates circle elements at the location of each found circle. |
