Mesures
- Joel Larose
Menu : Lidar Project / Tools / Measures
Measuring tools are imperative for any surveying and engineering projects. They provide data and information for a site's plan, design, and even assessments. Enhancement in technology brings virtual precise measurement accessible at your fingertips. In this chapter, we will see how to take measurements from point clouds and spherical images.
Six measurement tools are available. Each measurement made is drawn directly on the 3D scene as well as listed under the left panel where it can be saved in the cloud section of your account. Attached to this list, you will find a box which provides a report of the result describing the active measurement as well as the possibility of copying the information (position of the measurements) to the clipboard or deleting the measurement.
It is also possible to take measurements between any volumetric models added in the scene or between a point cloud and a model. Note that when you enter a point on the screen the color of the pointer will be green if the selected point comes from the point cloud and cyan if it comes from a volumetric model.
The measurement tools are described as follows:
Measure an angle by three points
Angle : 3 clicks are needed to build a triangular shape and thus display the angle of each vertex in degrees.
Holding the SHIFT key while entering a vertex displays the distance between two selected points.
Example of result displayed in the report
α = 44.7°, β = 75.3°, γ = 60.1°
Get the XYZ coordinates of a point
Point : Displays the XYZ coordinates of the selected point.
Example of result displayed in the report
134590.44000005722, 5163348.880000114, 261.8499984741211
Measure a distance according to the slope (3D distance)
3D distance: Distance according to the slope between two 3D coordinates (selected points) clicked on the screen. This measurement corresponds to the hypotenuse of a right-angled triangle formed by these two coordinates. It is also possible to take a series of consecutive measurements forming a polyline whose 3D distance is written inside each segment.
Click on the right mouse button to complete segment by abandoning the last unfinished entry.
Holding the SHIFT key while entering the vertices displays all the distances on each axis.
Example of result displayed in the report
ΔX,ΔY,ΔZ: -3.340,4.730,-0.100
Distances: 5.791
Total: 5.791 m
Measure an object height (vertical distance)
Height: Distance in elevation between two 3D coordinates (selected points) clicked on screen. This measurement is equivalent to a distance along the direction of gravity.
Holding the SHIFT key while entering the vertices displays all the distances on each axis.
Note, a visual line segment is drawn in 3D between the two coordinates selected although the distance displayed under this segment is a height.
Example of result displayed in the report
Height: 3.510 m
Width measurement of an object (horizontal distance)
2D distance: Horizontal distance between two 3D coordinates (selected points) clicked on screen. This distance measures a horizontal line between the plumb lines of two points.
Holding the SHIFT key while entering the vertices displays all the distances on each axis.
Note, the line segment is drawn in 3D between the two coordinates although the distance displayed under this segment is a horizontal distance.
Measure an area on a horizontal plane, a vertical plane or on an inclined plane
Surface: A surface measurement is equivalent to the area of a polygon formed by at least 3 vertices. The measurement is attached either to a vertical plane, a horizontal plane or to an average of an inclined plane. The value is displayed in the center of the polygon formed.
Click on the right mouse button to complete segment by abandoning the last unfinished entry.
3 options are available to calculate a surface (Area calculation mode available in the report box).
· Surface on a horizontal plane
· Surface on a vertical plane
· Surface on an inclined plane (slope)
Example of result displayed in the report
Area Calculation Mode: Slope
Surface: [P]:5.124 m²
Disable the magnifying glass when taking measurements
Although the magnifying glass is activated by default while measuring, there are two methods to deactivate or reactivate it:
From your keyboard, select the “z” key
On your main 3D scene, move your cursor to the top center which displays the hidden menu, and choose the magnifying glass icon
Edit an actual measurement on the 3D scene
Move the cursor on top of the vertex to be moved (switching to a white color) click and move the node to the desired location.
Save changes by tapping the Save icon (note, it is not possible to add or remove a vertex to an existing measurement)
It is not possible to add or remove a vertex to an existing measurement.
Possible actions applicable to all the measures taken
Delete | This action removes all measurement annotations from the 3D scene. For permanent deletion, the Save action must be performed afterwards. |
Save | This action saves measurement annotations to your cloud account. |
Reload | This action reloads previously saved cloud account measurement annotations. |
Export to file | This action exports any saved measurement annotations to a GeoJSON file format (only the vertices positions will be exported). |
Extra actions, specific to a measurement annotation
Lat/Long | This action displays the coordinates in latitude and longitude in the report. |
Locate | This action locates a measurement annotation on the 3D scene. |
Copy | This action copies all vertices position of a measurement annotation to the clipboard. |
Remove | This action removes all measurement annotations from the 3D scene. For permanent deletion, the Save action must be performed afterwards. |