LP360 FAQs

LP360 FAQs are some of the frequently asked questions about the LP360 product and workflows. See also, Frequently Asked Questions about LP360 installation and licensing.

1. Can LP360 Define Projection Information in a LAS File?

LP360’s LAS File Analyst can be used to verify, modify or add the required projection to any LAS formatted file.

2. Can I delete LIDAR points in LP360?

LP360 does not allow users the ability to delete any LIDAR points. Many of the industry standards specify that all points need to be left within the file. An example from the USGS specification says:
No points are to be deleted from the swath LAS files.

3. I checked do not show this warning, how do I uncheck/reset that warning?

You can reset your warning messages in…
LP360 for ArcGIS by selecting LP360 -> Project Settings -> Reset Warnings.
LP360/True View EVO by selecting File -> Project Settings -> Reset Warnings.

4. Does LP360 require a shapefile to run control against?

The LP360 Control Report does require a shapefile in order to run. The elevation field for the control report can either be an attribute field located within the table or the values can be pulled from the shape geometry if the file is 3D enabled.
If the user has an ASCII file instead of a shapefile, LP360 has the ability to import an ASCII XYZ file and convert it to a shapefile that can then be used to run control against.

5. Can LP360 Classify Points inside polygons?

Yes, LP360 has a Point Cloud Task called Classify by Feature that can be used to classify points either within a distance of or completely within a given feature class. In order to access the Point Cloud Task it will first need to be added via the Point Cloud Task Tab.

6. Can you batch point cloud tasks in LP360?

Among the Point Cloud Tasks within LP360 there is an option to create a macro. The macro task can be used to string together multiple Point Cloud Tasks, that run one after another. The ability to string the tasks together frees up the user from having to constantly monitor the machine to see if one task has finished so they can begin another task.
A common macro example is Building Classification and Footprint Extraction. The first task in the macro classifies data to the building classification and once that classification is complete the next task extracts footprints of the building class.
Most Point Cloud Tasks can also be executed from Python or Batch scripts using the LPRunPCT executable. Similarly, the LDExport executable can be used for exporting derivative products.

7. Why is there no data visible in the profile or 3D window?

Profile Window
There could be several reasons why data is not appearing in the profile window. Below are some things to check:
i) Was the profile tool used to draw around the area of interest or was the profile window just toggled on?  – If the profile window was toggled on use the Draw a profile line tool to generate the area of interest to be viewed within the window.
ii) Is the data in geographic coordinates? – LP360 does not display LIDAR data that is in geographic coordinate systems within the profile window. Please reproject the data to a projected system instead.
iii) Is the recenter z extent turn off and thus the data is below or above the field of view within the profile? – Turn on the recenter z extent button to allow the profile to recenter the data within the profile view.
iv) Is the “Display by…” button, the tri-state button you use to select the point attribute to display the by, depressed asking the software not to display any point data?
3D Window
There could be several reasons why data is not appearing in the 3D window. Below are some things to check:
i) Was the Draw 3D Extent tool used to draw around the area of interest or was the 3D window just toggled on?- If the 3D window was toggled on use the Define the 3D Window’s Extent tool to generate the area of interest to be viewed within the window.
ii) Is the data in geographic coordinates?- LP360 does not display LIDAR data that is in geographic coordinate systems within the 3D window. Please reproject the data to a projected system instead.
iii) Has the data been rotated and moved so it is no longer in the center of the view? – Use the Fit to Window tool or the View from the Top tool to recenter the data.
iv) Is the “Display by…” button, the tri-state button you use to select the point attribute to display the by, depressed asking the software not to display any point data?

8. Why is the LP360 Sketch Tool grayed out?

i) Make sure the active conflate task is setup to work with the geometry type of the target dataset.
ii) If the active conflate task stores elevations as attributes in the target dataset, make sure the conflate task is setup properly for the target dataset and the target dataset has the fields specified in the conflate task.
iii) If the active conflate task stores elevations in the vertices of the geometry, make sure the target dataset can store 3D geometry or Z values.
iv) When capturing delta/displacement summary values in the downstream conflation method, make sure you have assigned fields for each summary value and made sure those fields exist in the target database

9. Why does LIDAR data sometimes end up on different LIDAR Layers in LP360?

When data is originally added to LP360 the selected files will be grouped into layers, depending on certain criteria, so that only compatible LAS files will be on a single layer.  Criteria required for compatibility include:
* The coordinate system (when available)
* LAS format version
* Point Data Record Format (PDRF)
* GPS Time format
LAS files must have these 4 criteria in common to be considered compatible and grouped into the same layer. LP360 will create as many layers as necessary to represent each file selected to be opened.

The file list displays detailed information in columns for every LAS file selected to be added. This information is extracted from the LAS File or raster file header. You can click the columns to sort the data and then see which files are compatible (based on the criteria listed above). By default, only basic information columns are displayed, but you can click the Show Advanced Column button above the window to display much more information.

For additional information concerning combining data onto one layer within LP360 please review Putting LIDAR data on a single Layer.

10. What tools are available within LP360 to show point statistics?

LP360 has a Point Cloud Statistics Extractor Point Cloud Task that can be used to determine statistics about the LIDAR data within your project. For more in-depth information concerning setting up the Point Cloud Task please take a look at the article titled, “Importance of QAQC for LIDAR Datasets”, found in our Knowledge Center.
The task outputs the statistics information in a shapefile that represents the bounding boxes of the data, or the extents of the Point Cloud Task execution tool used to run the task. The shapefile’s attribute table contains the statistical information as defined by the task. Statistics can be calculated on the entire project, on a file by file basis, or within user digitized polygons or defined stamps and envelopes. Additionally, the data can be filtered if a user is only interested in calculating statistics on specific LIDAR characteristics, for instance Point Density for First Return LIDAR Points. Another option that determines how the information is grouped in the output table is the Group Attribute. This option is used when a user is interested in determining Point Density, or Point Count Totals, on a per Flightline basis. Then setting the Group Attribute to Flightline allows the statistics to be output in the output table based upon each Source Point ID.

11. What do the red exclamation marks on my LP360 layer indicate?

The red exclamation marks on a layer were added to indicate when there was a problem accessing one or more files on a layer. hey are normally encountered after seeing an error message, “Error occurred in opening at least one layer. LPMap::AddLayers(). Please Check file paths.” when opening a saved LP360 or True View EVO project. Hovering over the layer will reveal a tooltip, which shows more detail about the missing file(s). This generally occurs when opening a saved project file where the data may have been moved, deleted, or is in a location that is no longer accessible. Project files save absolute paths to the data, not relative paths, hence, you need to repath (File -> Repath) the files in the project if you move the data.

12. How can you stop the edge of the Project TIN from bleeding?

If you have long corridors, or non-rectangular projects, the TIN model formed in LP360 may connect a triangle from the lower section of the data to points in the upper section forming a surface across an area void of LIDAR points. There is no setting to exclude long triangles on the outside of a surface, however, one may digitize or generate polygons that define the areas adjacent to the LIDAR data that should be void of surface and include these in the breakline enforcement as “Out Areas” so that LP360 does not generate any triangles in these areas.

13. Can I extract RGB imagery with LP360?

LP360 can perform GIS Fusion where the image color from an orthophoto is displayed on the point cloud to assist with interpretation and data classification. However, there is not a supported method at this time for assigning the RGB values from the fusion (imagery) to the point cloud itself. Only True View EVO can do this for True View data.

14. Can I create breaklines automatically with LP360?

That depends on the definition of “automatic.”  We have invested extensively in breakline algorithms for LP360, primarily in support of hydrological modeling.  All of our tools currently require a “person in the loop” to collect (digitize) the X, Y components of the breakline.  The vertical is collecting automatically from the underlying point cloud using a rich variety of techniques.  We are actively engaged in new development for automatic morphology detection and will add these as they prove their robustness.

15. Can I use the 3D window in LP360 to classify points?

Not directly, however, when you select points for reclassification in the map or profile view all three views highlight the selected points so you can use the 3D Window to verify your point selection before committing the changes.

16. Can I use LAZ or ZLAS files in LP360?

ZLAS is an ESRI proprietary format that is not supported in LP360.
LAZ files may be added to an LP360 project, where LP360 supports the decompression and updating of LAZ files affected by changes made to the point data using LP360.

17. Can I automatically classify ground using LP360?

Yes, LP360 can automatically classify ground.  LP360 Advanced includes a robust implementation of the adaptive triangulated irregular network (TIN) classification algorithm.  In a recent ISPRS study that compared some 40+ ground classification algorithms, the adaptive TIN proved to be the best all-around ground classifier.

18. Can I automatically classify buildings using LP360?

LP360 Advanced includes a planer surface classification algorithm, a point cloud cluster vectorization tool and a “squaring” tool. These tools are combined into a building “roof print” extractor that, given input point cloud data, outputs a set of vectors that can be conflated to the ground to represent building footprints.

19. Is there a test in LP360 that can tell if I have duplicated points in a tile?

Yes, LP360 contains a Duplicate Points Classifier Point Cloud Task that can be used to identify and classify duplicate points.

20. Is it possible to clip or filter LIDAR files using a shapefile?

Yes, it is possible to both clip, and run point cloud tasks using an existing shapefile. Clipping, or filtering, may be accomplished using the Export Wizard found on the main LP360 toolbar. After selecting the desired points, using the Source Points filters, and the Export Format, in step 1, you can then select to “Cookie Cut by Polygons” in step 2 of the wizard. The same method may be used to clip derivative products, such as contours or DEM.
If one wishes to run Point Cloud Tasks, for example to filter the LIDAR data using an existing shapefile, this can be done using either the Execute Active Point Cloud Task using a Feature Layer, or the Execute Attribute derived Point Cloud Task using a Feature Layer execution options found on the LP360 Point Cloud Tasks toolbar.

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