bezier_curve {rayrender}

Bezier Curve Object

Description

Bezier curve, defined by 4 control points.

Usage

bezier_curve(
  p1 = c(0, 0, 0),
  p2 = c(-1, 0.33, 0),
  p3 = c(1, 0.66, 0),
  p4 = c(0, 1, 0),
  x = 0,
  y = 0,
  z = 0,
  width = 0.1,
  width_end = NA,
  u_min = 0,
  u_max = 1,
  type = "cylinder",
  normal = c(0, 0, -1),
  normal_end = NA,
  material = diffuse(),
  angle = c(0, 0, 0),
  order_rotation = c(1, 2, 3),
  flipped = FALSE,
  scale = c(1, 1, 1)
)

Arguments

p1

Default 'c(0,0,0)'. First control point. Can also be a list of 4 length-3 numeric vectors or 4x3 matrix/data.frame specifying the x/y/z control points.

p2

Default 'c(-1,0.33,0)'. Second control point.

p3

Default 'c(1,0.66,0)'. Third control point.

p4

Default 'c(0,1,0)'. Fourth control point.

x

Default '0'. x-coordinate offset for the curve.

y

Default '0'. y-coordinate offset for the curve.

z

Default '0'. z-coordinate offset for the curve.

width

Default '0.1'. Curve width.

width_end

Default 'NA'. Width at end of path. Same as 'width', unless specified.

u_min

Default '0'. Minimum parametric coordinate for the curve.

u_max

Default '1'. Maximum parametric coordinate for the curve.

type

Default 'cylinder'. Other options are 'flat' and 'ribbon'.

normal

Default 'c(0,0,-1)'. Orientation surface normal for the start of ribbon curves.

normal_end

Default 'NA'. Orientation surface normal for the start of ribbon curves. If not specified, same as 'normal'.

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 cube in the scene.

Examples

#Generate the default curve:
if(run_documentation()) {
generate_studio(depth=-0.2) %>%
  add_object(bezier_curve(material=diffuse(color="red"))) %>%
  add_object(sphere(y=3,z=5,x=2,radius=0.3,
                    material=light(intensity=200, spotlight_focus = c(0,0.5,0)))) %>%
  render_scene(clamp_value = 10, lookat = c(0,0.5,0), fov=13,
               samples=128)
}

if(run_documentation()) {
#Change the control points to change the direction of the curve. Here, we place spheres
#at the control point locations.
generate_studio(depth=-0.2) %>%
  add_object(bezier_curve(material=diffuse(color="red"))) %>%
  add_object(sphere(radius=0.075,material=glossy(color="green"))) %>% 
  add_object(sphere(radius=0.075,x=-1,y=0.33,material=glossy(color="green"))) %>% 
  add_object(sphere(radius=0.075,x=1,y=0.66,material=glossy(color="green"))) %>% 
  add_object(sphere(radius=0.075,y=1,material=glossy(color="green"))) %>% 
  add_object(sphere(y=3,z=5,x=2,radius=0.3,
                    material=light(intensity=200, spotlight_focus = c(0,0.5,0)))) %>%
  render_scene(clamp_value = 10, lookat = c(0,0.5,0), fov=15,
               samples=128)
}
if(run_documentation()) {
#We can make the curve flat (always facing the camera) by setting the type to `flat`
generate_studio(depth=-0.2) %>%
  add_object(bezier_curve(type="flat", material=glossy(color="red"))) %>%
  add_object(sphere(y=3,z=5,x=2,radius=0.3,
                    material=light(intensity=200, spotlight_focus = c(0,0.5,0)))) %>%
  render_scene(clamp_value = 10, lookat = c(0,0.5,0), fov=13,
               samples=128)
}
if(run_documentation()) {
#We can also plot a ribbon, which is further specified by a start and end orientation with
#two surface normals.
generate_studio(depth=-0.2) %>%
  add_object(bezier_curve(type="ribbon", width=0.2,
                   p1 = c(0,0,0), p2 = c(0,0.33,0), p3 = c(0,0.66,0), p4 = c(0.3,1,0),
                   normal_end = c(0,0,1),
                   material=glossy(color="red"))) %>%
  add_object(sphere(y=3,z=5,x=2,radius=0.3,
                    material=light(intensity=200, spotlight_focus = c(0,0.5,0)))) %>%
  render_scene(clamp_value = 10, lookat = c(0,0.5,0), fov=13,
               samples=128)
}
if(run_documentation()) {
#Create a single curve and copy and rotate it around the y-axis to create a wavy fountain effect:
scene_curves = list()
for(i in 1:90) {
  scene_curves[[i]] = bezier_curve(p1 = c(0,0,0),p2 = c(0,5-sinpi(i*16/180),2),
                            p3 = c(0,5-0.5 * sinpi(i*16/180),4),p4 = c(0,0,6),
                            angle=c(0,i*4,0), type="cylinder",
                            width = 0.1, width_end =0.1,material=glossy(color="red"))
}
all_curves = do.call(rbind, scene_curves)
generate_ground(depth=0,material=diffuse(checkercolor="grey20")) %>%
  add_object(all_curves) %>%
  add_object(sphere(y=7,z=0,x=0,material=light(intensity=100))) %>% 
  render_scene(lookfrom = c(12,20,50),samples=100,
               lookat=c(0,1,0), fov=15, clamp_value = 10)

}