R/geom_conn_bundle.R
geom_conn_bundle.Rd
Hierarchical edge bundling is a technique to introduce some order into the hairball structure that can appear when there's a lot of overplotting and edge crossing in a network plot. The concept requires that the network has an intrinsic hierarchical structure that defines the layout but is not shown. Connections between points (that is, not edges) are then drawn so that they loosely follows the underlying hierarchical structure. This results in a flow-like structure where lines that partly move in the same direction will be bundled together.
geom_conn_bundle(
mapping = NULL,
data = get_con(),
position = "identity",
arrow = NULL,
lineend = "butt",
show.legend = NA,
n = 100,
tension = 0.8,
...
)
geom_conn_bundle2(
mapping = NULL,
data = get_con(),
position = "identity",
arrow = NULL,
lineend = "butt",
show.legend = NA,
n = 100,
tension = 0.8,
...
)
geom_conn_bundle0(
mapping = NULL,
data = get_con(),
position = "identity",
arrow = NULL,
lineend = "butt",
show.legend = NA,
tension = 0.8,
...
)
Set of aesthetic mappings created by ggplot2::aes()
or ggplot2::aes_()
. By default x, y, xend, yend, group and
circular are mapped to x, y, xend, yend, edge.id and circular in the edge
data.
The result of a call to get_con()
Position adjustment, either as a string naming the adjustment
(e.g. "jitter"
to use position_jitter
), or the result of a call to a
position adjustment function. Use the latter if you need to change the
settings of the adjustment.
Arrow specification, as created by grid::arrow()
.
Line end style (round, butt, square).
logical. Should this layer be included in the legends?
NA
, the default, includes if any aesthetics are mapped.
FALSE
never includes, and TRUE
always includes.
It can also be a named logical vector to finely select the aesthetics to
display.
The number of points to create along the path.
How "loose" should the bundles be. 1 will give very tight bundles, while 0 will turn of bundling completely and give straight lines. Defaults to 0.8
Other arguments passed on to layer()
. These are
often aesthetics, used to set an aesthetic to a fixed value, like
colour = "red"
or size = 3
. They may also be parameters
to the paired geom/stat.
In order to avoid excessive typing edge aesthetic names are
automatically expanded. Because of this it is not necessary to write
edge_colour
within the aes()
call as colour
will
automatically be renamed appropriately.
geom_conn_bundle* understands the following aesthetics. Bold aesthetics are automatically set, but can be overwritten.
x
y
group
circular
edge_colour
edge_width
edge_linetype
edge_alpha
filter
The position along the path (not computed for the *0 version)
Holten, D. (2006). Hierarchical edge bundles: visualization of adjacency relations in hierarchical data. IEEE Transactions on Visualization and Computer Graphics, 12(5), 741-748. doi:10.1109/TVCG.2006.147
# Create a graph of the flare class system
library(tidygraph)
flareGraph <- tbl_graph(flare$vertices, flare$edges) %>%
mutate(
class = map_bfs_chr(node_is_root(), .f = function(node, dist, path, ...) {
if (dist <= 1) {
return(shortName[node])
}
path$result[[nrow(path)]]
})
)
importFrom <- match(flare$imports$from, flare$vertices$name)
importTo <- match(flare$imports$to, flare$vertices$name)
# Use class inheritance for layout but plot class imports as bundles
ggraph(flareGraph, 'dendrogram', circular = TRUE) +
geom_conn_bundle(aes(colour = after_stat(index)),
data = get_con(importFrom, importTo),
edge_alpha = 0.25
) +
geom_node_point(aes(filter = leaf, colour = class)) +
scale_edge_colour_distiller('', direction = 1, guide = 'edge_direction') +
coord_fixed() +
ggforce::theme_no_axes()