Generates delaunay triangles with ct_triangulate().
triangulate_delaunay(
boundaries,
with = NULL,
boundary = "sfa",
sample_surface = FALSE,
sample_points = FALSE,
nb_samples = NULL,
min_size = 1000,
seed = 1,
...
)
[sf] The boundaries to be used.
[sf] A set of data points to use for voronoisation.
[character] The column in boundaries
that is to
be used for the stratified sampling.
[logical] Whether to sample the surfaces in
boundaries
, Default to FALSE
.
[logical] Whether to sample points from with
or
to take all points in with
. Default to TRUE
.
[named character vector] The number of samples to draw
by boundary polygons (must bear the levels of boundary
as names
or be a single value to be applied to each level).
[numeric] The minimum size for a triangle above which it will be merged (in km2).
[numeric] Passed onto set.seed()
,
important for reproducibility of sampling.
Arguments passed on to RTriangle::triangulate
p
Planar straight line graph object; see
pslg
.
a
Maximum triangle area. If specified, triangles cannot be larger than this area.
q
Minimum triangle angle in degrees.
Y
If TRUE
prohibits the insertion of Steiner points
on the mesh boundary.
j
If TRUE
jettisons vertices that are not part of
the final triangulation from the output.
D
If TRUE
produce a conforming Delaunay
triangulation. This ensures that all the triangles in the mesh
are truly Delaunay, and not merely constrained Delaunay. This
option invokes Ruppert's original algorithm, which splits every
subsegment whose diametral circle is encroached. It usually
increases the number of vertices and triangles.
S
Specifies the maximum number of added Steiner points. If
set to Inf
, there is no limit on the number of Steine
points added - but this can lead to huge amounts of memory being
allocated.
V
Verbosity level. Specify higher values for more detailed information about what the Triangle library is doing.
Q
If TRUE
suppresses all explanation of what the
Triangle library is doing, unless an error occurs.
A named list with three elements (each an sf
object):
* patches
, the voronoi polygons generated
* points
, the points used for the tessellation.
data(borealis_simulated, package = "sspm")
data(sfa_boundaries, package = "sspm")
triangulate_delaunay(sfa_boundaries, with = borealis, sample_surface = TRUE,
boundary = "sfa", nb_samples = 10)
#> $patches
#> Simple feature collection with 70 features and 3 fields
#> Geometry type: MULTIPOLYGON
#> Dimension: XY
#> Bounding box: xmin: -62.90629 ymin: 46.20124 xmax: -47.38968 ymax: 60.62645
#> Geodetic CRS: WGS 84
#> # A tibble: 70 × 4
#> sfa patch_id patch_area geometry
#> * <chr> <fct> [km^2] <MULTIPOLYGON [°]>
#> 1 4 P1 3887. (((-60.6055 57.77918, -62.32017 59.94914, -61.1529…
#> 2 4 P2 9.49 (((-55.93264 50.03867, -56.20651 50.58302, -56.208…
#> 3 4 P3 15.9 (((-60.54276 57.694, -60.59819 57.76928, -60.62298…
#> 4 4 P4 0.299 (((-55.81365 49.79706, -55.73917 49.64616, -55.813…
#> 5 4 P5 448. (((-60.55599 57.66733, -58.87251 55.22493, -58.869…
#> 6 4 P6 1502. (((-61.15296 60.41194, -62.35403 59.93536, -61.786…
#> 7 4 P7 1654. (((-61.42425 59.70269, -60.87372 59.19752, -61.152…
#> 8 4 P8 1143. (((-61.78665 59.75678, -62.35403 59.93536, -61.000…
#> 9 4 P9 1779. (((-60.4377 58.93765, -61.00018 58.84686, -59.8071…
#> 10 4 P10 1469. (((-60.87372 59.19752, -60.4377 58.93765, -61.1529…
#> # ℹ 60 more rows
#>
#> $points
#> Simple feature collection with 40 features and 2 fields
#> Geometry type: POINT
#> Dimension: XY
#> Bounding box: xmin: -62.90629 ymin: 46.20124 xmax: -47.38968 ymax: 60.62645
#> Geodetic CRS: WGS 84
#> First 10 features:
#> sfa area geometry
#> 1 4 47575648300 [m^2] POINT (-62.90629 60.62645)
#> 2 4 47575648300 [m^2] POINT (-61.42425 59.70269)
#> 3 4 47575648300 [m^2] POINT (-59.80715 58.04987)
#> 4 4 47575648300 [m^2] POINT (-59.6313 57.70734)
#> 5 4 47575648300 [m^2] POINT (-61.00018 58.84686)
#> 6 4 47575648300 [m^2] POINT (-61.15296 60.41194)
#> 7 4 47575648300 [m^2] POINT (-60.87372 59.19752)
#> 8 4 47575648300 [m^2] POINT (-61.78665 59.75678)
#> 9 4 47575648300 [m^2] POINT (-62.35403 59.93536)
#> 10 4 47575648300 [m^2] POINT (-60.4377 58.93765)
#>