Constructive Solid Geometry Object

Source: R/csg_construct.R

This object takes an object constructed using the `csg_*` functions. The object is drawn using ray marching/sphere tracing.

csg_object(
  object,
  x = 0,
  y = 0,
  z = 0,
  material = diffuse(),
  angle = c(0, 0, 0),
  order_rotation = c(1, 2, 3),
  flipped = FALSE,
  scale = c(1, 1, 1)
)

Arguments

object

Object created with CSG interface.

x

Default `0`. x-offset of the center of the object.

y

Default `0`. y-offset of the center of the object.

z

Default `0`. z-offset of the center of the object.

material

Default diffuse. The material, called from one of the material functions diffuse, metal, or dielectric.

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".

flipped

Default `FALSE`. Whether to flip the normals.

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

Single row of a tibble describing the sphere in the scene.

Details

Note: For dielectric objects, any other objects not included in the CSG object and nested inside will be ignored.

Examples

# \donttest{
#We will combine these three objects:
generate_ground(material=diffuse(checkercolor="grey20")) %>%
  add_object(csg_object(csg_box(), material=glossy(color="red"))) %>% 
  add_object(csg_object(csg_sphere(radius=0.707), material=glossy(color="green"))) %>% 
  add_object(csg_object(csg_group(list(csg_cylinder(start=c(-1,0,0), end=c(1,0,0), radius=0.4),
                   csg_cylinder(start=c(0,-1,0), end=c(0,1,0), radius=0.4),
                   csg_cylinder(start=c(0,0,-1), end=c(0,0,1), radius=0.4))),
                   material=glossy(color="blue"))) %>% 
  add_object(sphere(y=5,x=3,radius=1,material=light(intensity=30))) %>%
  render_scene(clamp_value=10, fov=15,lookfrom=c(5,5,10), 
               samples=256, sample_method="sobol_blue")


#Standard CSG sphere + box - crossed cylinder combination:
generate_ground(material=diffuse(checkercolor="grey20")) %>%
  add_object(csg_object(csg_combine(
    csg_combine(
      csg_box(),
      csg_sphere(radius=0.707),
      operation="intersection"),
    csg_group(list(csg_cylinder(start=c(-1,0,0), end=c(1,0,0), radius=0.4),
                   csg_cylinder(start=c(0,-1,0), end=c(0,1,0), radius=0.4),
                   csg_cylinder(start=c(0,0,-1), end=c(0,0,1), radius=0.4))),
    operation="subtract"),
    material=glossy(color="red"))) %>%
  add_object(sphere(y=5,x=3,radius=1,material=light(intensity=30))) %>%
  render_scene(clamp_value=10, fov=10,lookfrom=c(5,5,10),
               samples=256, sample_method="sobol_blue")

  
#Blend them all instead:
generate_ground(material=diffuse(checkercolor="grey20")) %>%
  add_object(csg_object(csg_combine(
    csg_combine(
      csg_box(),
      csg_sphere(radius=0.707),
      operation="blend"),
    csg_group(list(csg_cylinder(start=c(-1,0,0), end=c(1,0,0), radius=0.4),
                   csg_cylinder(start=c(0,-1,0), end=c(0,1,0), radius=0.4),
                   csg_cylinder(start=c(0,0,-1), end=c(0,0,1), radius=0.4))),
    operation="blend"),
    material=glossy(color="purple"))) %>%
  add_object(sphere(y=5,x=3,radius=1,material=light(intensity=30))) %>%
  render_scene(clamp_value=10, fov=15,lookfrom=c(5,5,10), 
               samples=256, sample_method="sobol_blue")

# }