Render Points — render_points • rayshader

Adds 3D datapoints to the current scene, using latitude/longitude or coordinates in the reference system defined by the extent object. If no altitude is provided, the points will be elevated a constant offset above the heightmap. If the points goes off the edge, the nearest height on the heightmap will be used.

render_points(
  lat = NULL,
  long = NULL,
  altitude = NULL,
  extent = NULL,
  zscale = 1,
  heightmap = NULL,
  size = 3,
  color = "black",
  offset = 5,
  clear_previous = FALSE
)

Arguments

lat: Vector of latitudes (or other coordinate in the same coordinate reference system as extent).
long: Vector of longitudes (or other coordinate in the same coordinate reference system as extent).
altitude: Default `NULL`. Elevation of each point, in units of the elevation matrix (scaled by zscale). If a single value, all data will be rendered at that altitude.
extent: Either an object representing the spatial extent of the 3D scene (either from the `raster`, `terra`, `sf`, or `sp` packages), a length-4 numeric vector specifying `c("xmin", "xmax","ymin","ymax")`, or the spatial object (from the previously aforementioned packages) which will be automatically converted to an extent object.
zscale: Default `1`. The ratio between the x and y spacing (which are assumed to be equal) and the z axis in the original heightmap.
heightmap: Default `NULL`. Automatically extracted from the rgl window–only use if auto-extraction of matrix extent isn't working. A two-dimensional matrix, where each entry in the matrix is the elevation at that point. All points are assumed to be evenly spaced.
size: Default `3`. The point size. This can be a vector (the same length as `lat` and `long`) specifying a size for each point.
color: Default `black`. Color of the point. This can also be a vector specifying the color of each point.
offset: Default `5`. Offset of the track from the surface, if `altitude = NULL`.
clear_previous: Default `FALSE`. If `TRUE`, it will clear all existing points.

Examples

if(run_documentation()) {
#Starting at Moss Landing in Monterey Bay, we are going to simulate a flight of a bird going
#out to sea and diving for food.

#First, create simulated lat/long data
set.seed(2009)
moss_landing_coord = c(36.806807, -121.793332)
x_vel_out = -0.001 + rnorm(1000)[1:300]/1000
y_vel_out = rnorm(1000)[1:300]/200
z_out = c(seq(0,2000,length.out = 180), seq(2000,0,length.out=10),
         seq(0,2000,length.out = 100), seq(2000,0,length.out=10))

bird_track_lat = list()
bird_track_long = list()
bird_track_lat[[1]] = moss_landing_coord[1]
bird_track_long[[1]] = moss_landing_coord[2]
for(i in 2:300) {
bird_track_lat[[i]] = bird_track_lat[[i-1]] + y_vel_out[i]
bird_track_long[[i]] = bird_track_long[[i-1]] + x_vel_out[i]
}


#Render the 3D map
montereybay %>%
 sphere_shade() %>%
 plot_3d(montereybay,zscale=50,water=TRUE,
         shadowcolor="#40310a", background = "tan",
         theta=210,  phi=22, zoom=0.20, fov=55)

#Pass in the extent of the underlying raster (stored in an attribute for the montereybay
#dataset) and the latitudes, longitudes, and altitudes of the track.
render_points(extent = attr(montereybay,"extent"), 
             lat = unlist(bird_track_lat), long = unlist(bird_track_long), 
             altitude = z_out, zscale=50,color="white")
render_snapshot()
}

if(run_documentation()) {
#We'll set the altitude to zero to give the tracks a "shadow" over the water. 
render_points(extent = attr(montereybay,"extent"), 
             lat = unlist(bird_track_lat), long = unlist(bird_track_long), 
             offset = 0, zscale=50, color="black")
render_camera(theta=30,phi=35,zoom=0.45,fov=70)
render_snapshot()
}
#> Error in transform_into_heightmap_coords(extent, heightmap, lat, long,     altitude, offset, zscale): No altitude data requires heightmap argument be passed
if(run_documentation()) {
#Remove the points:
render_points(clear_previous=TRUE)

# Finally, we can also plot just GPS coordinates offset from the surface by leaving altitude `NULL`
# Here we plot a circle of values surrounding Moss Landing. This requires the original heightmap.

t = seq(0,2*pi,length.out=100)
circle_coords_lat = moss_landing_coord[1] + 0.3 * sin(t)
circle_coords_long = moss_landing_coord[2] + 0.3 * cos(t)
render_points(extent = attr(montereybay,"extent"), heightmap = montereybay,
           lat = unlist(circle_coords_lat), long = unlist(circle_coords_long), 
           zscale=50, color="red", offset=100, size=5)
render_camera(theta = 160, phi=33, zoom=0.4, fov=55)
render_snapshot()
}

if(run_documentation()) {
#And all of these work with `render_highquality()`
render_highquality(point_radius = 6, clamp_value=10, min_variance = 0,
                  sample_method = "sobol_blue", samples = 128)
}


if(run_documentation()) {
#We can also change the material of the objects by setting the `point_material` and
#`point_material_args` arguments in `render_highquality()`
render_highquality(point_radius = 6, clamp_value=10, min_variance = 0,
                  sample_method = "sobol_blue", samples = 128,
                  point_material = rayrender::glossy, 
                  point_material_args = list(gloss = 0.5, reflectance = 0.2))
}