persp3d {rgl} | R Documentation |
This function draws plots of surfaces over the
x-y plane. persp3d
is a generic function.
persp3d(x, ...) ## Default S3 method: persp3d(x = seq(0, 1, len = nrow(z)), y = seq(0, 1, len = ncol(z)), z, xlim = range(x, na.rm = TRUE), ylim = range(y, na.rm = TRUE), zlim = range(z, na.rm = TRUE), xlab = NULL, ylab = NULL, zlab = NULL, add = FALSE, aspect = !add, ...)
x, y |
locations of grid lines at which the values in z are
measured. These may be given as vectors or matrices.
If vectors, they must be in ascending order. Either one or both may matrices.
If x is a list ,
its components x$x and x$y are used for x
and y , respectively. |
z |
a matrix containing the values to be plotted.
Note that x can be used instead of z for
convenience. |
xlim, ylim, zlim |
x-, y- and z-limits. The plot is produced so that the rectangular volume defined by these limits is visible. |
xlab, ylab, zlab |
titles for the axes. N.B. These must be character strings; expressions are not accepted. Numbers will be coerced to character strings. |
add |
whether to add the points to an existing plot. |
aspect |
either a logical indicating whether to adjust the aspect ratio, or a new ratio |
... |
additional material parameters to be passed to surface3d
and decorate3d . |
This is similar to persp
with user interaction. See plot3d
for more general details.
One difference from persp
is that colors are specified on each
vertex, rather than on each facet of the surface. To emulate the persp
color handling, you need to do the following. First, convert the color vector to
an (nx-1)
by (ny-1)
matrix; then add an extra row before row 1,
and an extra column after the last column, to convert it to nx
by ny
.
(These extra colors will not be used). For example,
col <- rbind(0, cbind(matrix(col, nx-1, ny-1), 0))
.
Finally, call persp3d
with material property smooth = FALSE
.
If the x
or y
argument is a matrix, then it must be of the same
dimension as z
, and the values in the matrix will be used for the corresponding
coordinates. This is used to plot shapes such as spheres or cylinders
where z is not a function of x and y. See the fourth and fifth examples below.
This function is called for the side effect of drawing the plot. A vector of shape IDs is returned.
Duncan Murdoch
plot3d
, persp
. The curve3d
function in the emdbook
package draws surface plots of functions.
# (1) The Obligatory Mathematical surface. # Rotated sinc function. x <- seq(-10, 10, length= 30) y <- x f <- function(x,y) { r <- sqrt(x^2+y^2); 10 * sin(r)/r } z <- outer(x, y, f) z[is.na(z)] <- 1 open3d() bg3d("white") material3d(col="black") persp3d(x, y, z, aspect=c(1, 1, 0.5), col = "lightblue", xlab = "X", ylab = "Y", zlab = "Sinc( r )") # (2) Add to existing persp plot: xE <- c(-10,10); xy <- expand.grid(xE, xE) points3d(xy[,1], xy[,2], 6, col = "red", size = 3) lines3d(x, y=10, z= 6 + sin(x), col = "green") phi <- seq(0, 2*pi, len = 201) r1 <- 7.725 # radius of 2nd maximum xr <- r1 * cos(phi) yr <- r1 * sin(phi) lines3d(xr,yr, f(xr,yr), col = "pink", size = 2) # (3) Visualizing a simple DEM model z <- 2 * volcano # Exaggerate the relief x <- 10 * (1:nrow(z)) # 10 meter spacing (S to N) y <- 10 * (1:ncol(z)) # 10 meter spacing (E to W) open3d() bg3d("slategray") material3d(col="black") persp3d(x, y, z, col = "green3", aspect="iso", axes = FALSE, box = FALSE) # (4) A cylindrical plot z <- matrix(seq(0, 1, len=50), 50, 50) theta <- t(z) r <- 1 + exp( -pmin( (z - theta)^2, (z - theta - 1)^2, (z - theta + 1)^2 )/0.01 ) x <- r*cos(theta*2*pi) y <- r*sin(theta*2*pi) open3d() persp3d(x, y, z, col="red") # (5) A globe lat <- matrix(seq(90,-90, len=50)*pi/180, 50, 50, byrow=TRUE) long <- matrix(seq(-180, 180, len=50)*pi/180, 50, 50) r <- 6378.1 # radius of Earth in km x <- r*cos(lat)*cos(long) y <- r*cos(lat)*sin(long) z <- r*sin(lat) open3d() persp3d(x, y, z, col="white", texture=system.file("textures/worldsmall.png",package="rgl"), specular="black", axes=FALSE, box=FALSE, xlab="", ylab="", zlab="", normal_x=x, normal_y=y, normal_z=z) play3d(spin3d(axis=c(0,0,1), rpm=8), duration=5) ## Not run: # This looks much better, but is slow because the texture is very big persp3d(x, y, z, col="white", texture=system.file("textures/world.png",package="rgl"), specular="black", axes=FALSE, box=FALSE, xlab="", ylab="", zlab="", normal_x=x, normal_y=y, normal_z=z) ## End(Not run)