It may happen that you need to analyze the height difference between two point clouds acquired between a time interval. The data returned by this function is represented by a set of points placed at a height relative to zero and equal to the difference between the first cloud and the second.
If the document contains only two clouds, the dialog box is automatically pre-selected with the references relating to the clouds themselves. The position between minuend and subtrahend can be reversed.
The parameters available are the X and Y intervals of the sampler and the values range from 0.1 units to 100. The destination layer is fixed and is emptied, if present, at each processing. Therefore, if the comparison between more than two clouds is required, it is advisable to rename the output file for each processing before starting the next one.
Before activating this feature, a surface must be created for each cloud. The function that creates the surface from a cloud is described in this article.
With this feature it is possible to quickly obtain information on surface slip for landslide areas, glaciers, quarries etc…