Functions to compute colors modified for lighting effects.
Usage
phongLighting(normals, view, light, color, color2, alpha, material = "default")
perspLighting(normals, view, light, color, color2, alpha, material = "default")
Arguments
normals
numeric matrix with three columns representing surface
normal vectors.
view
numeric vector of length 3 representing the direction to
the viewer.
light
numeric vector of length 3 or 4. The first three
elements represent the direction to the light. The fourth element,
if present, represents light intensity; the default is 1.
color
colors to use for faces in the direction of the normal
vectors.
color2
opposite face color.
alpha
alpha channel level, a number between 0 and 1.
material
material specification. Currently possible values are
the character strings "dull", "shiny", "metal", and "default".
Details
phongLighting uses the Phong lighting model to compute colors
modified for view direction, light direction, and material properties.
perspLighting implements approximately the same lighting model
as the persp function.