• Rolling back use of native pipe (#364 and #365)

• Fix a precision bug in circle pack layout (#345)
• GeomEdgeTile now uses edge_width instead of edge_size for the border
• Fix a bug in geom_edge_parallel() when used with edge labels. Edges are now
  correctly offset, though label may still overlap (#227)
• Fix a bug with auto layout on undirected trees (#247)
• Fix a bug in get_con() that would lead to wrong matching of additional data
  (#249)
• Allow na.rm in geoms (#301)
• If check_overlap = TRUE in geom_node_text() the rendering order is
  reversed so that the top nodes are rendered, not the bottom ones
• Updated guides to the new ggplot2 interface. For guide_edge_direction(),
  this update adds the option to use labels instead of an arrow using the
  labels argument.
• create_layout() now returns a modified tibble rather than a data.frame
• The ... in get_nodes(), get_edges(), and get_con() now accepts
  tidy evaluation. get_nodes() and get_con() will get evaluated on the node
  data in the original order (layouts may reorder nodes), and get_edges() will
  get evaluated on the edge data (#272)
• The linear layout has gained a weight argument allowing you to set how much
  space each node occupy. Further, the layout now calculates statistics so that
  it can be used in conjunction with geom_node_tile() and geom_node_arc_bar()
• New layout added. Cactustree is a hierarchical layout optimised for
  hierarchical edge bundling by placing nodes as budding circles on the
  periphery of their parent (#226)
• Updated layout functions from the graphlayouts package to support grouped and
  constrained versions (centrality, focus, and stress layouts)
• Added H Tree layout for binary trees (#58)
• Added geom_edge_bundle_force(), geom_edge_bundle_path(), and
  geom_edge_bundle_minimal() (+ variants) to provide support for edge bundling
  (#267)
• Add "metro" layout from graphlayouts for metroline like layouts
• Add layout_sf(), geom_node_sf() and geom_edge_sf() to support plotting of
  sfnetwork objects (#275)

• Update errors to use cli
• Use vctrs internally
• Add binned edge scales
• Fix a bug where removing the full data with a filter would throw an error
• Make sure all lyaout functions now correctly merge the layout with the node
  data without getting duplicate column names
• Fixed a bug in the start_cap implementation that would cause edges consisting
  of only two points to disappear
• Fixed a bug in facet_graph() when using . on either dimension (#313)
• Move dendrogram layout calculations to compiled code to avoid R's recursion
  stack limitations (#311)
• Fixed a bug in the circle pack algorithm that could result in overlapping
  circles (#305)

• Fix vignette errors on CRAN

• Fix deprecation of std::random_shuffle in C++14 by specifyin C++11 as the
  compile version

• Fix bug in faceting functions where using algorithms based on sampling
  directly would result in errors
• Move CI to GitHub Actions
• Warn if a precalculated layout is passed to layout in create_layout()
  (#208)
• Warn when setting dim to a value higher than 2 in igraph layouts (#160)
• Fix bug when trying to plot a graph with no edges (#214)
• Fix a bug in edge geoms due to a typo (#246)
• Fix a bug in edge geoms where setting label_colour to NA would turn it off
  instead of inheriting the colour of the edge (#238)
• Fix a bug in edge geoms that prevented edge labels from being parsed as
  expressions (#245)
• Improve performance of dendrogram layout when calculating depth (#248)
• Fix a bug in hive layout when segmenting by a factor with unused levels (#252)
• Fix a bug in capping of path due to updates in grid. Setting cap unit to
  native now works as expected again (#254)
• Fix a bug in get_con() that would require input to be sorted in the from
  vector (#258)

• Fix bug in geom_edge_elbow() that resulted in duplicated group columns in
  the data.

• Remove reshape2 dependency

• Fix bug in ggraph that will surface with the next grid release
• Deprecate qgraph() in favour of autograph() to avoid name collision with
  qgraph::qgraph(). autograph() is now also a generic with a default method,
  so you can provide your own specific ggraph plot method for your network
  classes

This release is a major release including many new features, bug fixes and some
breaking changes.

Breaking changes

• Use tidygraph as the central data format. The results of this are several:

  • All graph object supported by tidygraph are now supported on even footing in
    ggraph. All layouts are now available to any graph class
  • BREAKING The "even" layout for dendrograms are no more, but can be
    obtained by using the "dendrogram" layout with height = NULL
  • BREAKING All layouts uses NSE for arguments that refer to node and edge
    variables, instead of passing in strings that refer to the variable name.
  • All examples and vignettes now uses tidygraph for graph manipulation
    resulting in much cleaner code.
  • tree_apply has been removed in favour of using tidygraph::map_bfs_*
  • geom_edge_elbow is no longer only available to dendrogram objects
  • tidygraph algorithms can now be used directly within ggraph functions. E.g.
    you can have sort.by = node_rank_hclust() in your specification of a
    linear layout, or aes(colour = group_infomap()) in node geoms

  This big change fixes #21, #72, #79, and #81. A vignette has been added to
  describe the integration in more detail

• The curvature argument from geom_edge_arc() and geom_edge_hive() as well
  as the spread argument from geom_edge_fan() has been deprecated in favor
  of the new strength argument.

• ggraph plots now gets constructed with grid and axes removed from the default
  theme.

New features

• Add equal-angle and equal-daylight unrooted tree layouts (#59)
• Interface with the graphlayouts package and make all its layouts available.
  The auto layout now uses the stress layout for standard graphs (sparse stress)
  for larger graphs.
• Added length argument to the dendrogram layout to allow the layout to be based
  on edge length rather than node heights (#124).
• Added geom_edge_parallel() for drawing multiedges as parallel lines (#191)
• Added fabric layout to create biofabric plots. Also added geom_node_range()
  and geom_edge_span() for visualising such layouts (#47)
• Added geom_edge_bend() for drawing soft elbows (#45)
• Added geom_node_voronoi() for displaying nodes as voronoi tiles (#100)
• Added qgraph() for quickly creating a standard network plot for explorative
  purpose (#94)
• All non-straight line-based edge geoms now has a strength parameter that
  controls their deviation from a straight line. 0 will always give a straight
  line while 1 will be their natural look. Numbers outside this range may look
  weird (#97)
• Added weight and mode arguments to get_con() that are passed on to the
  shortest path calculations (#89).
• Add matrix layout and geom_edge_point() (#23)
• Added geom_edge_tile() for use with matrix layouts (#141)
• Manual layouts are now easier to specify. You can pass a matrix or data.frame
  to the layout parameter that will then be used. Also, if an x and y
  argument is present, the auto layout will choose the manual layout. (#91)
• Custom layout functions are now much more flexible. And can either return a
  data.frame or an object coercible to a tbl_graph. In the latter case the
  node table will be used as layout and the graph will be attached. This allows
  direct use of the particles package as a layout engine as a side effect. (#88)

Bug fixes

• Fixed numerious bugs and issues pertaining to the group aesthetic handling in
  many edge geoms (#190, #193).
• Edge geoms no longer throws an error when all edges are completely capped
  (#176)
• Fixed a bug that prevented edge capping from being used with *2 variants of
  edge geoms (#167)
• Fix bug in edge capping that could lead to edges extending to (0,0) (#163)
• Fix bug affecting faceting of capped edges (#140)
• Character aesthetics are no longer cast to factors in edge geoms (#131)
• Fix a bug where start capping was ignored if the previous edge had been
  completely removed by capping (#150)
• Fix offsetting bug in edge label drawing when some labels are empty strings
  and label_parse = TRUE (#159)
• Fixed a bug resulting in the wrong mapping of additional values to connections
  (#122, #134)
• Fixed a bug when using facet_graph() with data from both tbl_df and
  data.frame
• Added override.aes to guide_edge_direction()
• Fix bug with extracting edges from an empty graph (#76)
• Fixed bug causing shifts in edge aesthetics when one or more edges were
  completely clipped (#62, #115)
• Fixed bug when clipping completely orthogonal points that produced additional
  lines going to (0,0) (#70, #84, #103)

Other

• Changed license to MIT
• Update roxygen documentation to use markdown and reduce duplication (#95)