extruded_polygon: Extruded Polygon Object

In rayrender: Build and Raytrace 3D Scenes

Extruded Polygon Object

Description

Extruded Polygon Object

Usage

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

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)

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:

hollow_star = rbind(star_polygon, 0.8 * star_polygon)

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
	)

# Render one in the y-x plane as well by changing the `plane` argument,
# as well as offset it slightly.
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
	)

# Now add the zy plane:
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
     )

#We can also directly pass in sf polygons:
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.
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.
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.

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
	)

rayrender documentation built on Sept. 16, 2026, 9:08 a.m.