Adds a marker and label to the current 3D plot

render_label(
  heightmap,
  text,
  lat,
  long,
  altitude = NULL,
  extent = NULL,
  x = NULL,
  y = NULL,
  z = NULL,
  zscale = 1,
  relativez = TRUE,
  offset = 0,
  clear_previous = FALSE,
  textsize = 1,
  dashed = FALSE,
  dashlength = "auto",
  linewidth = 3,
  antialias = FALSE,
  alpha = 1,
  textalpha = 1,
  freetype = TRUE,
  adjustvec = NULL,
  family = "sans",
  fonttype = "standard",
  linecolor = "black",
  textcolor = "black"
)

Arguments

heightmap

A two-dimensional matrix, where each entry in the matrix is the elevation at that point. All points are assumed to be evenly spaced.

text

The label text.

lat

A latitude for the text. Must provide an `raster::extent` object to argument `extent` for the map.

long

A latitude for the text. Must provide an `raster::extent` object to argument `extent` for the map.

altitude

Default `NULL`. Elevation of the label, in units of the elevation matrix (scaled by zscale). If none is passed, this will default to 10 percent above the maximum altitude in the heightmap.

extent

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

x

Default `NULL`. Directly specify the `x` index in the matrix to place the label.

y

Default `NULL`. Directly specify the `y` index in the matrix to place the label.

z

Default `NULL`. Elevation of the label, in units of the elevation matrix (scaled by zscale).

zscale

Default `1`. The ratio between the x and y spacing (which are assumed to be equal) and the z axis. For example, if the elevation levels are in units

relativez

Default `TRUE`. Whether `z` should be measured in relation to the underlying elevation at that point in the heightmap, or set absolutely (`FALSE`).

offset

Elevation above the surface (at the label point) to start drawing the line.

clear_previous

Default `FALSE`. If `TRUE`, it will clear all existing text and lines rendered with `render_label()`. If no other arguments are passed to `render_label()`, this will just remove all existing lines.

textsize

Default `1`. A numeric character expansion value.

dashed

Default `FALSE`. If `TRUE`, the label line is dashed.

dashlength

Default `auto`. Length, in units of the elevation matrix (scaled by `zscale`) of the dashes if `dashed = TRUE`.

linewidth

Default `3`. The line width.

antialias

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

alpha

Default `1`. Transparency of the label line.

textalpha

Default `1`. Transparency of the label text.

freetype

Default `TRUE`. Set to `FALSE` if freetype is not installed (freetype enables anti-aliased fonts). NOTE: There are occasionally transparency issues when positioning Freetype fonts in front and behind a transparent surface.

adjustvec

Default `c(0.5,-0.5)`. The horizontal and vertical offset for the text. If `freetype = FALSE` and on macOS/Linux, this is adjusted to `c(0.33,-0.5)` to keep the type centered.

family

Default `"sans"`. Font family. Choices are `c("serif", "sans", "mono", "symbol")`.

fonttype

Default `"standard"`. The font type. Choices are `c("standard", "bold", "italic", "bolditalic")`. NOTE: These require FreeType fonts, which may not be installed on your system. See the documentation for rgl::text3d() for more information.

linecolor

Default `black`. Color of the line.

textcolor

Default `black`. Color of the text.

Examples

# \dontrun{
montereybay %>%
 sphere_shade() %>%
 plot_3d(montereybay,zscale=50,water=TRUE, watercolor="#233aa1")
render_snapshot() 

# }

santa_cruz = c(36.962957, -122.021033) 
#We want to add a label to Santa Cruz, so we use the x and y matrix coordinate (x=220 and y=330)
# \dontrun{
render_label(montereybay,lat = santa_cruz[1], long = santa_cruz[2],
            extent = attr(montereybay, "extent"),
            altitude=12000, zscale=50, text = "Santa Cruz")
render_snapshot()

# }

monterey = c(36.603053, -121.892933)
#We can also change the linetype to dashed by setting `dashed = TRUE` (additional options allow
#the user to control the dash length). You can clear the existing lines by setting 
#`clear_previous = TRUE`.
# \dontrun{
render_label(montereybay, lat = monterey[1], long = monterey[2], altitude = 10000, 
            extent = attr(montereybay, "extent"),
            zscale = 50, text = "Monterey", textcolor = "white", linecolor="darkred",
            dashed = TRUE, clear_previous = TRUE)
render_snapshot()

# }

canyon = c(36.621049, -122.333912)
#By default, z specifies the altitude above that point on the elevation matrix. We can also specify 
#an absolute height by setting `relativez=FALSE`.
# \dontrun{
render_label(montereybay,lat=canyon[1], long = canyon[2], altitude = 2000,
            extent = attr(montereybay,"extent"),
            zscale=50,text = "Monterey Canyon", relativez=FALSE)
render_snapshot()

# }

#We can also render labels in high quality with `render_highquality()`, specifying a custom
#line radius. By default, the labels point towards the camera, but you can fix their angle with
#argument `text_angle`.
# \dontrun{
render_camera(theta=35, phi = 35, zoom = 0.80, fov=60)
render_label(montereybay, lat = monterey[1], long = monterey[2], altitude = 10000, 
            extent = attr(montereybay, "extent"),
            zscale = 50, text = "Monterey", textcolor = "white", linecolor="darkred",
            dashed = TRUE, clear_previous = TRUE)
               
render_label(montereybay,lat=canyon[1], long = canyon[2], altitude = 2000, zscale=50,
            extent = attr(montereybay,"extent"), textcolor = "white", linecolor="white",
            text = "Monterey Canyon", relativez=FALSE)
            
render_highquality(samples=200,text_size = 24, line_radius = 2, text_offset = c(0,20,0),
                  lightdirection=180, clamp_value=10)

                  
#Fixed text angle
render_highquality(samples=200,text_size = 24, line_radius = 2, text_offset = c(0,20,0),
                  lightdirection=180, text_angle=0, clamp_value=10)

# }
#We can remove all existing labels by calling `render_label(clear_previous = TRUE)`
# \dontrun{
render_label(clear_previous = TRUE) 
render_snapshot()

rgl::rgl.close()
# }