fasterRaster has limited support for 3-dimensional
GRasters and GVectors. A GRaster
is like a multi-layered raster, except that layers contain values in
“voxels” (3-dimensional pixels), where each layer has a z-resolution, in
addition to its normal x- and y-resolutions. These layers are called
“depths”. A 3-dimensional vector has a z-dimension, so any point (i.e.,
an actual point, or points that together define a line or polygon) has a
third dimension. You can test if an object is 3-dimensional using
topology(), is.2d(), or is.3d(),
or by looking at its metadata (i.e., just enter the name of the object
in R and look at what is displayed).
Thus far, no functions that handle 3-dimensional
GRasters or GVectors have been tested.
Some functions like spatSample() have arguments that allow
you to do something with a z-component. Also, some of the “getter”
functions can report information about the third dimension of a
GRaster or GVector.
Three-dimensional GRasters and GVectors
should (?… remember, no testing yet!) work with most functions. In some
cases, the third dimension will be ignored or removed. You should get a
warning in these cases.
| Function | Object type | 
|---|---|
| bottom() | GRasterorGVector | 
| dim3d() | GRaster | 
| is.2d() | GRasterorGVector | 
| is.3d() | GRasterorGVector | 
| ncell3d() | GRaster | 
| ndepth() | GRaster | 
| res3d() | GRaster | 
| top() | GRasterorGVector | 
| topology() | GRasterorGVector | 
| zext() | GRasterorGVector | 
| zres() | GRaster | 
~ FINIS ~