sprites.RdAdds a sprite set shape node to the scene.
sprites3d(x, y = NULL, z = NULL, radius = 1,
shapes = NULL, userMatrix,
fixedSize = FALSE,
adj = 0.5, pos = NULL, offset = 0.25,
rotating = FALSE, ...)
particles3d(x, y = NULL, z = NULL, radius = 1, ...)point coordinates. Any reasonable way of defining the
coordinates is acceptable. See the function xyz.coords
for details.
vector or single value defining the sprite radius
NULL for a simple square, a vector of
identifiers of shapes in the scene, or a list of
such vectors. See Details.
if shape is not NULL, the transformation matrix
for the shapes
should sprites remain at a fixed size, or resize with the scene?
positioning arguments; see Details
should sprites remain at a fixed orientation, or rotate with the scene?
material properties when shapes = NULL, texture mapping is supported
Simple sprites (used when shapes is NULL) are 1 by 1 squares
that are directed towards the viewpoint. Their primary use is for
fast (and faked) atmospherical effects, e.g. particles and clouds
using alpha blended textures. Particles are sprites using an alpha-blended
particle texture giving the illusion of clouds and gases.
The centre of each square will by default be at the
coordinates given by x, y, z. This may be adjusted
using the adj or pos parameters.
adj and pos are treated similarly to the same
parameters for text3d. adj has 3
entries, for adjustment to the x, y and
z coordinates respectively. For x, a value
of 0 puts the sprite to the right of the specified point,
0.5 centers it there, and 1 puts it to the left. The other
coordinates are similar. By default, each value is 0.5 and
the sprites are centered at the points given by (x, y, z).
The pos parameter overrides adj. It should
be an integer or vector of integers (one per point),
interpreted as in text3d to position the
sprite relative to the (x, y, z) point: 0 is centered on it, 1 is below,
2 is to the left, 3 is above, 4 is to the right, 5 is in
front, and 6 is behind. offset is the
fraction of the sprite size to separate it from the point.
When shapes is not NULL, it should be a vector of
identifiers of objects to plot in the scene (e.g. as returned by
plotting functions or by ids3d), or a list of such vectors. The referenced objects will
be removed from the scene and duplicated as sprite images in a
constant orientation, as specified by userMatrix. By default the
origin (0, 0, 0) will be plotted at the coordinates given by (x, y, z), perhaps modified by adj
or pos.
If shapes is a vector all entries in it will be plotted at every
location. If shapes is a list, different shapes
will be plotted at each location. All entries in list
entry 1 will be plotted
at location 1, all entries in entry 2 at location 2, etc.
Entries will be recycled as needed.
The userMatrix argument is ignored for shapes = NULL. For
shapes, sprites3d defaults the matrix to r3dDefaults$userMatrix.
If any coordinate is NA, the sprite is not plotted.
The id values of the shapes may be retrieved after plotting
using rgl.attrib(id, "ids"), the associated entry
in shapes
is retrievable in rgl.attrib(id, "shapenum"), and
the user matrix is retrieved using rgl.attrib(id, "usermatrix").
While any rgl objects can be used as 3D sprites, spheres
produced by spheres3d and other objects that
adapt to the coordinate system
may not render properly. To plot spheres, construct them
as mesh objects as shown in the example.
These functions are called for the side effect of displaying the sprites. The shape ID of the displayed object is returned.
open3d()
particles3d( rnorm(100), rnorm(100), rnorm(100), color = rainbow(100) )
# is the same as
sprites3d( rnorm(100), rnorm(100), rnorm(100), color = rainbow(100),
lit = FALSE, alpha = .2,
textype = "alpha", texture = system.file("textures/particle.png", package = "rgl") )
sprites3d( rnorm(10) + 6, rnorm(10), rnorm(10), shape = shade3d(tetrahedron3d(), col = "red") )
3D plot
open3d()
# Since the symbols are objects in the scene, they need
# to be added to the scene after calling plot3d()
plot3d(iris, type = "n")
# Use list(...) to apply different symbols to different points.
symbols <- list(shade3d(cube3d(), col = "red"),
shade3d(tetrahedron3d(), col = "blue"),
# Construct spheres
shade3d(addNormals(subdivision3d(icosahedron3d(), 2)),
col = "yellow"))
sprites3d(iris, shape = symbols[iris$Species], radius = 0.1)
3D plot