label_fill_JamPolygon: Arrange text labels inside a polygon

In jmw86069/venndir: Directional Venn diagrams

Arrange text labels inside a polygon

Description

Arrange text labels inside a polygon

Usage

label_fill_JamPolygon(
  jp,
  labels,
  buffer = -0.15,
  relative = TRUE,
  color = "black",
  border = NA,
  ref_jp = NULL,
  xyratio = 1.1,
  fontsize = 10,
  cex = 1,
  degrees = 0,
  dither_cex = 0.04,
  dither_color = 0.07,
  dither_degrees = 0,
  scale_width = -0.15,
  apply_n_scale = TRUE,
  buffer_w = 0,
  buffer_h = 0,
  label_method = c("hexagonal"),
  layout_degrees = -20,
  draw_buffer = FALSE,
  buffer_fill = "#FFFFFF77",
  buffer_border = "red",
  draw_points = FALSE,
  draw_labels = TRUE,
  seed = 1,
  plot_style = c("base", "gg", "none"),
  verbose = FALSE,
  ...
)

Arguments

jp	JamPolygon where only the first row is processed.
labels	character vector of labels

Details

This function is intended to define points inside a polygon area which are evenly spaced, used to place text labels also inside the polygon. There are limited options to define a buffer region so that labels do not overlap the polygon boundary.

Strategy

• Determine bounding box with rectangular area that encompases the polygon.

• Define evenly spaced points across the rectangular area sufficient to produce at least n total points.

• Retain only the subset of points which are inside the polygon.

• If there are fewer than n remaining points, repeat the process using a higher target value for n.

Challenges:

• polyclip::pointinpolygon() does not appear to handle polygons with holes. If not, then we have to use logic like: "overlaps any solid polygon, does not overlap any polygon hole".

Options:

• Consider applying a buffer with fixed width inside the original polygon, so that points have at least this minimum width to the polygon border.

• Bonus points for applying the buffer more to the width than height, since text labels are typically wider than they are tall.

See Also

Other JamPolygon: JamPolygon-class, Venndir-class, add_orientation_JamPolygon(), area_JamPolygon(), bbox_JamPolygon(), buffer_JamPolygon(), check_JamPolygon(), check_Venndir(), eulerr_to_JamPolygon(), farthest_point_JamPolygon(), find_venn_overlaps_JamPolygon(), has_point_in_JamPolygon(), intersect_JamPolygon(), label_outside_JamPolygon(), label_segment_JamPolygon(), labelr_JamPolygon(), minus_JamPolygon(), nearest_point_JamPolygon(), plot,JamPolygon,missing-method, plot.JamPolygon(), point_in_JamPolygon(), polyclip_to_JamPolygon(), sample_JamPolygon(), split_JamPolygon(), union_JamPolygon(), update_JamPolygon()

Examples

df3 <- data.frame(name=c("polygon1", "polygon2"),
   label=c("polygon1", "polygon2"),
   x=I(list(
      list(c(1, 6, 6, 1),
         c(2, 5, 5, 2),
         c(3, 4, 4, 3)),
      list(#c(11, 16, 16, 11),
         c(12, 15, 15, 12),
         c(13, 14, 14, 13))
      )),
   y=I(list(
      list(c(1, 1, 6, 6),
         c(2, 2, 5, 5),
         c(3, 3, 4, 4)),
      list(#c(1, 1, 6, 6),
         c(2, 2, 5, 5),
         c(3, 3, 4, 4))
      )),
   fill=c("gold", "firebrick"))
jp3 <- new("JamPolygon", polygons=df3);
plot(jp3);

label_fill_JamPolygon(jp3[1,], labels=1:20)
test_x <- jp3[1,]@polygons$x[[1]];
test_y <- jp3[1,]@polygons$y[[1]];
P <- list(x=c(3.5, 4.5), y=c(3.5, 4.5))
A <- lapply(seq_along(test_x), function(i){
   list(x=test_x[[i]], y=test_y[[i]])})

jmw86069/venndir documentation built on June 15, 2024, 1:52 p.m.