rayshader (version 0.25.2)

render_path: Render Path

Description

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

Usage

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

Arguments

extent

A `raster::Extent` object with the bounding box of the displayed 3D scene.

lat

Vector of latitudes (or other coordinate in the same coordinate reference system as extent). Can also be an `sf` or `SpatialLineDataFrame` object.

long

Default `NULL`. Vector of longitudes (or other coordinate in the same coordinate reference system as extent). Ignored if lat is an `sf` or `SpatialLineDataFrame` object.

altitude

Default `NULL`. Elevation of each point, in units of the elevation matrix (scaled by zscale). If left `NULL`, this will be just the elevation value at ths surface, offset by `offset`.

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.

linewidth

Default `3`. The line width.

color

Default `black`. Color of the line.

antialias

Default `FALSE`. If `TRUE`, the line with be have anti-aliasing applied. NOTE: anti-aliasing can cause some unpredictable behavior with transparent surfaces.

offset

Default `5`. Offset of the track from the surface, if `altitude = NULL`.

clear_previous

Default `FALSE`. If `TRUE`, it will clear all existing paths.

Examples

# NOT RUN {
#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", watercolor="#233aa1", 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_path(extent = attr(montereybay,"extent"), 
           lat = unlist(bird_track_lat), long = unlist(bird_track_long), 
           altitude = z_out, zscale=50,color="white", antialias=TRUE)
render_snapshot()
    
#We'll set the altitude to right above the water to give the tracks a "shadow".
render_path(extent = attr(montereybay,"extent"), 
           lat = unlist(bird_track_lat), long = unlist(bird_track_long), 
           altitude = 10, zscale=50, color="black", antialias=TRUE)
render_camera(theta=30,phi=35,zoom=0.45,fov=70)
render_snapshot()
#Remove the path:
render_path(clear_previous=TRUE)

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

t = seq(0,2*pi,length.out=1000)
circle_coords_lat = moss_landing_coord[1] + 0.5 * t/8 * sin(t*6)
circle_coords_long = moss_landing_coord[2] + 0.5 * t/8 *  cos(t*6)
render_path(extent = attr(montereybay,"extent"), heightmap = montereybay,
           lat = unlist(circle_coords_lat), long = unlist(circle_coords_long), 
           zscale=50, color="red", antialias=TRUE,offset=100, linewidth=5)
render_camera(theta = 160, phi=33, zoom=0.4, fov=55)
render_snapshot()

#And all of these work with `render_highquality()`
render_highquality(clamp_value=10, line_radius=3)
rgl::rgl.close()
# }