The metro style

Reproduces dagviz's StyleConfig defaults (style/metro.py) as a dag_style_metro object: round nodes (the default shape; see node_shape of dag_layers()), thick colored edges with rounded bends, and labels to the right.

Usage

style_metro(
  scale = 10,
  node_radius = 6,
  node_fill = NULL,
  node_stroke = "white",
  node_stroke_width = 2,
  edge_stroke_width = 2,
  label_font_family = "sans-serif",
  label_font_size = "inherit",
  label_font_color = "currentColor",
  label_arrow_stroke = "lightgrey",
  label_arrow_dash_array = "2",
  arc_radius = 15,
  bridge_color = "white",
  minimal_width = NULL,
  node_size_range = NULL,
  edge_width_range = NULL
)

Arguments

scale

Half the distance, in pixels, between neighboring rows and between neighboring lanes (columns): both are 2 * scale apart.

node_radius

The radius of a node, in pixels: of a circle, and the size that other shapes (see node_shape of dag_layers()) are drawn to match. A triangle or diamond reaches further from its center than a circle, up to about 1.6 times node_radius, and the plot ends only scale pixels from the nodes' centers, so with a node_radius of about 7 or more (at the default scale) a triangle in the first or last row may be cut off: raise scale too.

node_fill

Optional single fill color for every node, used only when node_color (a separate argument to the plotting functions) is left at its default. Unlike node_color, it never affects edge colors (matching dagviz: node_fill recolors place_node() only, never _place_edge()). NULL (the default) uses the resolved palette instead.

node_stroke, node_stroke_width

The color and width of a node's border.

edge_stroke_width

The line width of an edge.

label_font_family, label_font_size, label_font_color

The font family, size (in pixels) and color of a node's label. Accept either dagviz's own StyleConfig values (the defaults: "sans-serif", "inherit", "currentColor") or their R equivalents directly.

label_arrow_stroke, label_arrow_dash_array

The color and linetype of the leader line from a node to its label. label_arrow_dash_array accepts dagviz's SVG stroke-dasharray value (the default, "2") or an R linetype code (e.g. "22") directly.

arc_radius

The radius of an input arc.

bridge_color

The color of the white "bridge" drawn under a horizontal line where it crosses other edges.

minimal_width

How far the plot extends to the right of its labels. NULL (the default) ends the plot just past the longest label, measured from its text. A number is dagviz's rule instead: the plot is at least that wide in pixels (dagviz uses 500) and twice as wide as the right-most label's start, since an SVG can't measure its own text. The plot is then often much wider than the graph.

node_size_range, edge_width_range

The smallest and largest node radius and edge width, in pixels, when node_size and edge_width (see dag_layers()) draw them from a column. Rows and lanes are 2 * scale apart, and the plot ends scale pixels from the nodes' centers, so a radius may not exceed scale, nor a width scale / 2. NULL (the default) is from half to one and a half times node_radius, and from half to two and a half times edge_stroke_width, kept within those limits. The limit is for circles: a triangle or diamond reaches up to about 1.6 times further, as for node_radius, so the biggest of them in the first or last row may be cut off unless scale is raised. Neighboring rows are 2 * scale apart, so two nodes of the largest radius in them leave only 2 * scale - 2 * max px for the line between them (2 px by default), too little to see. A smaller maximum, or a larger scale, leaves room.

Value

A dag_style_metro object.

Examples

style_metro()
#> $scale
#> [1] 10
#> 
#> $node_radius
#> [1] 6
#> 
#> $node_fill
#> NULL
#> 
#> $node_stroke
#> [1] "white"
#> 
#> $node_stroke_width
#> [1] 2
#> 
#> $edge_stroke_width
#> [1] 2
#> 
#> $label_font_family
#> [1] "sans"
#> 
#> $label_font_size
#> [1] 16
#> 
#> $label_font_color
#> [1] "black"
#> 
#> $label_arrow_stroke
#> [1] "lightgray"
#> 
#> $label_arrow_dash_array
#> [1] "22"
#> 
#> $arc_radius
#> [1] 15
#> 
#> $bridge_color
#> [1] "white"
#> 
#> $minimal_width
#> NULL
#> 
#> $node_size_range
#> NULL
#> 
#> $edge_width_range
#> NULL
#> 
#> attr(,"class")
#> [1] "dag_style_metro"
dag <- as_dag(data.frame(from = c("a", "a", "b"), to = c("b", "c", "c")))
ggplot_dag(dag, style = style_metro(node_radius = 9, arc_radius = 12, scale = 12))