Menu: Survey / Sidewalk detection
This tool automatically detects the top and bottom of a sidewalk and vectorizes them. The detection will create points along the edge as long as the parameters are met. This function needs a good density of points so that the edges are correctly detected.
Here are the parameters:
Lenght: Maximum legnth of the search box
Width: Maximum width of the search box.
Height: Maximum height of the search box. This value must be kept as close to reality as possible for the detection to work properly.
Seg. Length: Maximum distance for the segment to be considerate valide.
Tol. distance: Maximum tolerance to search for the next point.
- Tol.deviation: Maximum deviation of the polyline from one segment to the next
- Tol.verticality: Maximum angle to detect the bottm of the curb (deviation from the 90° reference).
- Min. point: Minimum of points within the box to be considerate valid for the detection.
Highest points / Lowest points: Select a Pcodes to the top edge & bottom edge to identify the type of element in your CAD.
Once the parameters are setup, you will have to go to "Search by" and select between 2 options.
- Two points: You will pick the starting point of the detection and the 2nd point will indicate the direction to follow for the detection
- By Trajectory: Select an alignment or the camera path (For MMS) for automatic batch detection. You will have to select the offset left & right (search distance from the trajectory) and the start/end of the search by entering the index number for each or clicking on the point cloud directly ( you will need to click on "Start index" and "End index" respectively prior to click on the point cloud).
Once the mode selected, then click on "Start detection"
Once the detection is done you will have the possibilty to adjust the vectorization to fit better your point cloud. To do so, you have access to "Fitting"
- Fit in XY: Straighten the lines in X & Y
- Fit in XYZ: Straighten the lines in X, Y & Z
- Spline: Adjust the line to follow the curb
- BSpline:
Once you are done with the detection, you will have the option to:
- Save: Saves the selected polylines to a PLN format.
- Load: Loads a PLN file to the item list while clearing existing items.
- Append: Adds a PLN file to the item list. Does not clear existing items.
- Export: Exports selected polylines to .DXF, .MID or .SHP, GeoJSON or .KML format.
- Create chains: see "Picking points and lines".
