USE THE CLOUDWORX SLICE TOOLBAR
I. Use the CloudWorx Slice Toolbar to slice the point cloud from the top view (or whichever view allows you to see the entire diameter of the column/feature); this will be the only section profile that will be traced and we will only be tracing half of it; choosing the most complete/intact slice possible is recommended. See Method 1 for details on slicing
TRACE THE PROFILE AND SNAP TO POINT CLOUD
II. Trace the profile of the section cut, snapping directly to point cloud > Front or Side View > Make correct layer current > Zoom in to view points comfortably and refresh point cloud to confirm all points visible (do this periodically, especially when zooming in/out) > Command Line: PL or POLYLINE and begin to trace the profile/outline the profile of the section cut
REMEMBER: (1) Enable OSNAP “NODE” to snap to points (2) At command line: type “U” during active polyline command to undo vertices/go back without ending the command (3) At command line: PEDIT allows polyline(s) to be edited, joined, etc. (4) See ACAD Help: Drawing and Editing Polylines for more information
DETERMINE CENTER AROUND WHICH TO ROTATE
B. OSNAPS – enable ENDPOINT and MIDPOINT -> Use ONSNAPS to draw a line that is perpendicular to the column’s profile polyline: the start point snaps to the endpoint of the top of the column and the end point snaps to the point cloud on the opposite edge of the section cut – this line represents the full diameter of the column. Draw another line in the same way at the bottom of the column (See Figures 12 & 13)
C. Use OSNAPS to snap to the midpoint of the line at the top of the column to the midpoint of the line at the bottom of the column – this line represents the center of the column (TIP: When snapping to midpoint, a triangle and the word “midpoint” appears near the cursor) -> Use grips or the TRIM command to trim the ends of the lines that protrude past the center line
NOTE: This method finds the center based on the diameter of the column at the top and bottom at the point of the slice, accounting for any leaning/tilting along the z-direction; For generally upright features, drawing a line in the center and restricting it to the z-axis will result in more regularized features with identical “up directions”
IV. Command line: PEDIT to edit the polylines and join them into a single closed polyline > PEDIT > Select original polyline > JOIN > Select centerline, top line, and bottom line > ENTER 2X > Clicking on the polyline should confirm that it is now a single object (if it does not join, check to confirm no endpoints are snapped to one another but they are NOT overlapping).
ROTATE PROFILE TO FORM 3D OBJECT
6. Modeled object can now be edited or exported as desired.
You are reading the series: Modeling an Irregular Feature from Point Cloud Data - 3D
- Modeling an Irregular Feature from Point Cloud Data – Method 1
- Modeling an Irregular Features – Method 2
- Modeling an Irregular Features – Comparing Modeled Objects to Original Points