Extruded Polygon Object

extruded_polygon(
  polygon = NULL,
  x = 0,
  y = 0,
  z = 0,
  plane = "xz",
  top = 1,
  bottom = 0,
  holes = NULL,
  angle = c(0, 0, 0),
  order_rotation = c(1, 2, 3),
  material = diffuse(),
  center = FALSE,
  flip_horizontal = FALSE,
  flip_vertical = FALSE,
  data_column_top = NULL,
  data_column_bottom = NULL,
  scale_data = 1,
  scale = c(1, 1, 1)
)

Arguments

polygon: `sf` object, "SpatialPolygon" `sp` object, or xy coordinates of polygon represented in a way that can be processed by `xy.coords()`. If xy-coordinate based polygons are open, they will be closed by adding an edge from the last point to the first. If the `sf` object contains MULTIPOLYGONZ data, it will flattened.
x: Default `0`. x-coordinate to offset the extruded model.
y: Default `0`. y-coordinate to offset the extruded model.
z: Default `0`. z-coordinate to offset the extruded model.
plane: Default `xz`. The plane the polygon is drawn in. All possibile orientations are `xz`, `zx`, `xy`, `yx`, `yz`, and `zy`.
top: Default `1`. Extruded top distance. If this equals `bottom`, the polygon will not be extruded and just the one side will be rendered.
bottom: Default `0`. Extruded bottom distance. If this equals `top`, the polygon will not be extruded and just the one side will be rendered.
holes: Default `0`. If passing in a polygon directly, this specifies which index represents the holes in the polygon. See the `earcut` function in the `decido` package for more information.
angle: Default `c(0, 0, 0)`. Angle of rotation around the x, y, and z axes, applied in the order specified in `order_rotation`.
order_rotation: Default `c(1, 2, 3)`. The order to apply the rotations, referring to "x", "y", and "z".
material: Default diffuse.The material, called from one of the material functions diffuse, metal, or dielectric.
center: Default `FALSE`. Whether to center the polygon at the origin.
flip_horizontal: Default `FALSE`. Flip polygon horizontally in the plane defined by `plane`.
flip_vertical: Default `FALSE`. Flip polygon vertically in the plane defined by `plane`.
data_column_top: Default `NULL`. A string indicating the column in the `sf` object to use to specify the top of the extruded polygon.
data_column_bottom: Default `NULL`. A string indicating the column in the `sf` object to use to specify the bottom of the extruded polygon.
scale_data: Default `1`. If specifying `data_column_top` or `data_column_bottom`, how much to scale that value when rendering.
scale: Default `c(1, 1, 1)`. Scale transformation in the x, y, and z directions. If this is a single value, number, the object will be scaled uniformly. Note: emissive objects may not currently function correctly when scaled.

Value

Multiple row tibble describing the extruded polygon in the scene.

Examples

if (run_documentation()) {
angles = seq(0, 360, by = 36)
xx = rev(c(rep(c(1, 0.5), 5), 1) * sinpi(angles / 180))
yy = rev(c(rep(c(1, 0.5), 5), 1) * cospi(angles / 180))
star_polygon = data.frame(x = xx, y = yy)
}

if (run_documentation()) {
generate_ground(
  depth = 0,
  material = diffuse(color = "grey50", checkercolor = "grey20")
) |>
  add_object(extruded_polygon(
    star_polygon,
    top = 0.5,
    bottom = 0,
    material = diffuse(color = "red", sigma = 90)
  )) |>
  add_object(sphere(
    y = 4,
    x = -3,
    z = -3,
    material = light(intensity = 30)
  )) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(0, 2, 3),
    samples = 16,
    lookat = c(0, 0.5, 0),
    fov = 60
  )
}


#Now, let's add a hole to the center of the polygon. We'll make the polygon
#hollow by shrinking it, combining it with the normal size polygon,
#and specify with the `holes` argument that everything after `nrow(star_polygon)`
#in the following should be used to draw a hole:

if (run_documentation()) {
hollow_star = rbind(star_polygon, 0.8 * star_polygon)
}

if (run_documentation()) {
generate_ground(
  depth = -0.01,
  material = diffuse(color = "grey50", checkercolor = "grey20")
) |>
  add_object(extruded_polygon(
    hollow_star,
    top = 0.25,
    bottom = 0,
    holes = nrow(star_polygon) + 1,
    material = diffuse(color = "red", sigma = 90)
  )) |>
  add_object(sphere(
    y = 4,
    x = -3,
    z = -3,
    material = light(intensity = 30)
  )) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(0, 2, 4),
    samples = 16,
    lookat = c(0, 0, 0),
    fov = 30
  )
}
#> Warning: coercing argument of type 'double' to logical


# Render one in the y-x plane as well by changing the `plane` argument,
# as well as offset it slightly.
if (run_documentation()) {
generate_ground(
  depth = -0.01,
  material = diffuse(color = "grey50", checkercolor = "grey20")
) |>
  add_object(extruded_polygon(
    hollow_star,
    top = 0.25,
    bottom = 0,
    holes = nrow(star_polygon),
    material = diffuse(color = "red", sigma = 90)
  )) |>
  add_object(extruded_polygon(
    hollow_star,
    top = 0.25,
    bottom = 0,
    y = 1.2,
    z = -1.2,
    holes = nrow(star_polygon) + 1,
    plane = "yx",
    material = diffuse(color = "green", sigma = 90)
  )) |>
  add_object(sphere(y = 4, x = -3, material = light(intensity = 30))) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(0, 2, 4),
    samples = 16,
    lookat = c(0, 0.9, 0),
    fov = 40
  )
}
#> Warning: coercing argument of type 'double' to logical


# Now add the zy plane:
if (run_documentation()) {
generate_ground(
  depth = -0.01,
  material = diffuse(color = "grey50", checkercolor = "grey20")
) |>
  add_object(extruded_polygon(
    hollow_star,
    top = 0.25,
    bottom = 0,
    holes = nrow(star_polygon) + 1,
    material = diffuse(color = "red", sigma = 90)
  )) |>
  add_object(extruded_polygon(
    hollow_star,
    top = 0.25,
    bottom = 0,
    y = 1.2,
    z = -1.2,
    holes = nrow(star_polygon) + 1,
    plane = "yx",
    material = diffuse(color = "green", sigma = 90)
  )) |>
  add_object(extruded_polygon(
    hollow_star,
    top = 0.25,
    bottom = 0,
    y = 1.2,
    x = 1.2,
    holes = nrow(star_polygon) + 1,
    plane = "zy",
    material = diffuse(color = "blue", sigma = 90)
  )) |>
  add_object(sphere(y = 4, x = -3, material = light(intensity = 30))) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(-4, 2, 4),
    samples = 16,
    lookat = c(0, 0.9, 0),
    fov = 40
  )
}
#> Warning: coercing argument of type 'double' to logical
#> Warning: coercing argument of type 'double' to logical
#> Warning: coercing argument of type 'double' to logical


#We can also directly pass in sf polygons:
if (run_documentation()) {
if (length(find.package("spData", quiet = TRUE)) > 0) {
  us_states = spData::us_states
  texas = us_states[us_states$NAME == "Texas", ]
  #Fix no sfc class in us_states geometry data
  class(texas$geometry) = c("list", "sfc")
}
}

#This uses the raw coordinates, unless `center = TRUE`, which centers the bounding box
#of the polygon at the origin.
if (run_documentation()) {
generate_ground(
  depth = -0.01,
  material = diffuse(color = "grey50", checkercolor = "grey20")
) |>
  add_object(extruded_polygon(
    texas,
    center = TRUE,
    material = diffuse(color = "#ff2222", sigma = 90)
  )) |>
  add_object(sphere(
    y = 30,
    x = -30,
    radius = 10,
    material = light(color = "lightblue", intensity = 40)
  )) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(0, 10, -10),
    samples = 16,
    fov = 60
  )
}


#Here we use the raw coordinates, but offset the polygon manually.
if (run_documentation()) {
generate_ground(
  depth = -0.01,
  material = diffuse(color = "grey50", checkercolor = "grey20")
) |>
  add_object(extruded_polygon(
    us_states,
    x = 96,
    z = -40,
    top = 2,
    material = diffuse(color = "#ff2222", sigma = 90)
  )) |>
  add_object(sphere(
    y = 30,
    x = -100,
    radius = 10,
    material = light(color = "dodgerblue", intensity = 200)
  )) |>
  add_object(sphere(
    y = 30,
    x = 100,
    radius = 10,
    material = light(color = "orange", intensity = 200)
  )) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(0, 120, -120),
    samples = 160,
    fov = 20
  )
}


#We can also set the map the height of each polygon to a column in the sf object,
#scaling it down by the maximum population state.

if (run_documentation()) {
generate_ground(
  depth = 0,
  material = diffuse(color = "grey50", checkercolor = "grey20", sigma = 90)
) |>
  add_object(extruded_polygon(
    us_states,
    x = 96,
    z = -45,
    data_column_top = "total_pop_15",
    scale_data = 1 / max(us_states$total_pop_15) * 5,
    material = diffuse(color = "#ff2222", sigma = 90)
  )) |>
  add_object(sphere(
    y = 30,
    x = -100,
    z = 60,
    radius = 10,
    material = light(color = "dodgerblue", intensity = 250)
  )) |>
  add_object(sphere(
    y = 30,
    x = 100,
    z = -60,
    radius = 10,
    material = light(color = "orange", intensity = 200)
  )) |>
  render_scene(
    parallel = TRUE,
    lookfrom = c(60, 50, -40),
    lookat = c(0, -5, 0),
    samples = 160,
    fov = 30
  )
}