R: Computes the polygon that encloses the points

catalog_boundaries {lidR} | R Documentation

## Computes the polygon that encloses the points

### Description

Computes the polygon that encloses the points. It reads all the files one by one and computes a concave hull using the concaveman function. When all the hulls are computed it updates the LAScatalog to set the true polygons instead of the bounding boxes.

### Usage

    catalog_boundaries(ctg, concavity = 5, length_threshold = 5)

### Arguments

`ctg` | A LAScatalog
`concavity` | numeric. A relative measure of concavity. 1 results in a relatively detailed shape, Infinity results in a convex hull. You can use values lower than 1, but they can produce pretty crazy shapes.
`length_threshold` | numeric. When a segment length is under this threshold, it stops being considered for further detailed processing. Higher values result in simpler shapes.

### Value

A LAScatalog with true boundaries

### Supported processing options

Supported processing options for more details see the LAScatalog engine documentation:

- chunk size: Not supported, it processes by file.

- chunk buffer: Not supported, it processes by file with no buffer.

- chunk alignment: Not supported, it processes by file.

- progress: Displays a progress estimate.

- output files: Not supported, it returns an R object.

- select: Not supported, it loads XYZ only.

- filter: Read only the points of interest.

### Examples

    LASfile <- system.file("extdata", "Megaplot.laz", package="lidR")
    ctg <- readLAScatalog(LASfile, filter = "-drop_z_below 0.5")
    ctg2 <- catalog_boundaries(ctg, 1, 15)
    plot(ctg)
    plot(ctg2, add = TRUE)

[Package lidR version 3.2.2 Index]