Getting started with dragmapr

dragmapr is built around a deliberately small loop for draggable plots:

  1. Start with projected sf geometry and a grouping column.
  2. Open the draggable browser helper with drag_map_prototype(open = TRUE).
  3. Drag regions, labels, or annotation boxes until the layout looks right.
  4. Copy or download the offset CSVs from the helper panel.
  5. Optionally reproduce the layout as a static ggplot2 image with render_dragged_map().

The interactive helper is the primary deliverable. Step 5 is optional — use it when you need a reproducible image for a report or publication.

Toy geometry

All examples below use a projected toy dataset so the workflow can be tested without downloading shapefiles.

library(dragmapr)

make_square <- function(x0, y0, size = 100000) {
  sf::st_polygon(list(rbind(
    c(x0, y0), c(x0 + size, y0), c(x0 + size, y0 + size),
    c(x0, y0 + size), c(x0, y0)
  )))
}

regions <- sf::st_sf(
  region = c("North", "South", "East", "West"),
  label  = c("North", "South", "East", "West"),
  geometry = sf::st_sfc(
    make_square(0,       140000),
    make_square(0,            0),
    make_square( 140000,  70000),
    make_square(-140000,  70000),
    crs = 3857
  )
)

drag_map_prototype() — full parameter reference

Data

These three arguments identify the geometry and what to group or label.

Argument Default Description
x (required) Projected sf object. Must not be in a geographic (lon/lat) CRS.
region_col (required) Column name that defines draggable groups.
label_col region_col Column used for label text. Defaults to the grouping column. 
# Minimal call — one grouping column used for both groups and labels
drag_map_prototype(regions, region_col = "region", open = TRUE)

# Separate column for label text
drag_map_prototype(regions, region_col = "region", label_col = "label", open = TRUE)

Labels

Control whether labels appear and whether they can be dragged independently.

Argument Default Description
labels TRUE TRUE derives one label per region automatically. FALSE shows no labels. Supply a data frame from as_drag_labels() or as_drag_annotations() for custom labels.
draggable_labels TRUE When TRUE, labels can be moved independently. When FALSE, labels follow their region but cannot be repositioned on their own. 
# No labels
drag_map_prototype(regions, region_col = "region", labels = FALSE, open = TRUE)

# Labels follow regions but cannot be dragged separately
drag_map_prototype(regions, region_col = "region",
                   draggable_labels = FALSE, open = TRUE)

# Custom label data frame
custom_labels <- make_region_labels(regions, region_col = "region", label_col = "label")
drag_map_prototype(regions, region_col = "region",
                   labels = custom_labels, open = TRUE)

Label styling

Choose between three marker shapes for short text labels — rounded box, circle, or text-only — and control their sizes and font.

Argument Default Description
label_marker TRUE Draw a visible marker shape behind label text. FALSE is a shortcut for label_marker_shape = "none".
label_marker_shape "rect" Shape behind the label text: "rect" (rounded box), "circle", or "none" (text only with an invisible drag target).
label_text_size 11 Label text size in browser pixels. Applies to all label types.
label_width 64 Width of rounded-box label markers in pixels.
label_height 30 Height of rounded-box label markers in pixels.
label_radius 12 Circle radius in pixels. Used when label_marker_shape = "circle".
label_box_width 150 Width of draggable annotation box (info-box style) in pixels.
label_box_height 72 Height of draggable annotation box in pixels. 
# Rounded-box markers (default) — adjust size and text
drag_map_prototype(
  regions, region_col = "region",
  label_marker_shape = "rect",
  label_text_size    = 12,
  label_width        = 80,
  label_height       = 32,
  open = TRUE
)

# Circle markers
drag_map_prototype(
  regions, region_col = "region",
  label_marker_shape = "circle",
  label_radius       = 18,
  label_text_size    = 11,
  open = TRUE
)

# Text only — no visible marker, just draggable text
drag_map_prototype(
  regions, region_col = "region",
  label_marker_shape = "none",
  label_text_size    = 13,
  open = TRUE
)

# Annotation boxes (info-box style with connectors)
notes <- as_drag_annotations(
  make_region_labels(regions, region_col = "region"),
  width_px       = 160,
  height_px      = 70,
  connector      = TRUE,
  connector_type = "elbow"
)
drag_map_prototype(
  regions, region_col = "region",
  labels           = notes,
  label_box_width  = 160,
  label_box_height = 70,
  open = TRUE
)

Connectors

Connector lines link a label or annotation box back to its region anchor. They are only drawn for labels that have connector = TRUE in their label data frame — set that flag via as_drag_annotations(..., connector = TRUE) or as_drag_labels(). The line style ("straight", "elbow", "curve", "squiggle") is stored per-label in the connector_type column.

Argument Default Description
connector_color "#334155" Browser connector line colour.
connector_linewidth 1.3 Connector line thickness in browser pixels.
connector_linetype "solid" Browser connector line pattern: "solid", "dashed", or "dotted".
connector_endpoint "none" Browser connector endpoint: "none" or "arrow".
connector_smart FALSE Let the browser choose straight, elbow, or curved connector geometry from the current label displacement. 
drag_map_prototype(
  regions, region_col = "region",
  labels              = notes,   # labels with connector = TRUE
  connector_color     = "#334155",
  connector_linewidth = 2,
  connector_linetype  = "dashed",
  connector_endpoint  = "arrow",
  connector_smart     = TRUE,
  open = TRUE
)

Movement context

Movement context is optional and off by default. It helps explain where a moved region came from without changing the underlying offset data.

Argument Default Description
show_origin_outlines FALSE Draw the original outline for regions with non-zero offsets.
show_movement_connectors FALSE Draw a line from each moved region’s original representative point to its current location.
movement_connector_color "#64748b" Movement connector colour.
movement_connector_opacity 0.72 Movement connector opacity from 0 to 1.
movement_connector_linewidth 1.4 Browser movement connector thickness in pixels.
movement_connector_linetype "solid" Movement connector pattern: "solid", "dashed", or "dotted".
movement_connector_endpoint "closed" Movement connector endpoint: "closed", "open", or "none".
show_drag_trail FALSE Browser-only fading outline trail while a region is actively dragged. 
drag_map_prototype(
  regions, region_col = "region",
  show_origin_outlines = TRUE,
  show_movement_connectors = TRUE,
  movement_connector_color = "#64748b",
  movement_connector_linetype = "dashed",
  movement_connector_endpoint = "open",
  show_drag_trail = TRUE,
  open = TRUE
)

Static exports support origin outlines and movement connectors too:

render_dragged_map(
  regions,
  region_offsets = region_offsets,
  region_col = "region",
  show_origin_outlines = TRUE,
  show_movement_connectors = TRUE,
  movement_connector_linetype = "dotted",
  movement_connector_endpoint = "closed"
)

Initial positions

Supply previously exported offset tables to pre-load a saved layout so dragging can continue from where it left off.

Argument Default Description
region_offsets NULL Data frame with columns region, dx_m, dy_m. All regions start at zero when NULL.
label_offsets NULL Data frame with columns label_id, region, dx_m, dy_m. All labels start at zero when NULL. 
# Resume from previously downloaded CSVs
region_csv <- read_offsets("drag_region_offsets.csv")
label_csv  <- read_label_state("drag_label_offsets.csv")

drag_map_prototype(
  regions, region_col = "region",
  region_offsets = region_csv,
  label_offsets  = label_csv,
  open = TRUE
)

read_label_offsets() is retained as an alias for read_label_state(), and apply_label_offsets() is retained as an alias for apply_label_state(). Likewise, make_labels() remains an alias for make_region_labels() for older scripts.

If the offsets were exported as a Spatial Studio project ZIP, use the one-line project renderer instead of wiring the CSV files together manually:

render_dragmapr_project(
  "dragmapr-project.zip",
  file = "dragged-map.png"
)

RStudio addin

In RStudio, install the package and use Addins > Launch dragmapr to open a compact prototype gadget. The addin looks for sf objects in .GlobalEnv, lets you choose the region and label columns, and assigns region_offsets and label_offsets when you click Done. Create or load the sf object before opening the addin. If you call dragmapr_addin() directly, pass env = to work with another environment.

Colour palette

Argument Default Description
region_palette NULL Named character vector mapping each region value to a hex colour string. Uses a built-in 8-colour cycling palette when NULL.

Matching the interactive palette to a render_dragged_map() call makes the draggable preview and the final static image look identical.

my_palette <- c(
  North = "#4C78A8",
  South = "#F58518",
  East  = "#54A24B",
  West  = "#B279A2"
)

drag_map_prototype(
  regions, region_col = "region",
  region_palette = my_palette,
  show_legend    = TRUE,
  open = TRUE
)

Legend

A compact colour legend can be embedded directly inside the browser helper. It is hidden by default because many maps are labelled and need no legend.

Argument Default Description
show_legend FALSE Show a colour legend in the helper.
max_legend_keys 25 Suppress the legend automatically when the number of groups exceeds this value. Set to Inf to always show it regardless of group count.
legend_position "bottom" Where the legend appears: "bottom", "top", "left", "right", or "none".
legend_title "Region" Title shown above the legend keys.
legend_values NULL Optional character vector of region values to include in the legend. NULL includes all values. 
drag_map_prototype(
  regions, region_col = "region",
  region_palette  = my_palette,
  show_legend     = TRUE,
  legend_position = "bottom",   # "top" | "left" | "right" | "none"
  legend_title    = "Region",
  legend_values   = c("North", "East"),
  max_legend_keys = 25,
  open = TRUE
)

Use label_values when an app should temporarily display only selected labels while preserving all label offsets:

drag_map_prototype(
  regions, region_col = "region",
  label_values = c("North", "East"),
  open = TRUE
)

Output file and display

Argument Default Description
file "drag-map.html" File path for the written standalone HTML.
open FALSE Open the file in the default browser via browseURL() after writing.
side_panel TRUE Show the built-in copy/download side panel. Shiny apps that provide their own export controls can set this to FALSE to reclaim the full canvas.
map_background "white" Helper background: "white", "transparent", "light_grid", or "dark". 
# Write to a chosen path without opening (e.g. CI, server, or Shiny)
drag_map_prototype(
  regions, region_col = "region",
  file       = "output/my_map.html",
  map_background = "light_grid",
  side_panel = TRUE,
  open       = FALSE
)

# Embedded in a Shiny app — hide the panel; the app provides its own controls
drag_map_prototype(
  regions, region_col = "region",
  side_panel = FALSE,
  file       = tempfile(fileext = ".html")
)

Optional: Static rendering

When you need a reproducible ggplot2 image, pass the exported offset tables to render_dragged_map(). The data frames below stand in for downloaded CSVs:

region_offsets <- data.frame(
  region = c("North", "South", "East", "West"),
  dx_m   = c(0, 0,  60000, -60000),
  dy_m   = c(50000, -50000, 0, 0)
)

label_state <- data.frame(
  label_id = c("North", "South", "East", "West"),
  region   = c("North", "South", "East", "West"),
  dx_m     = c(0, 0,  25000, -25000),
  dy_m     = c(30000, -30000, 0, 0)
)

render_dragged_map(
  regions,
  region_offsets = region_offsets,
  region_col     = "region",
  label_col      = "label",
  label_offsets  = label_state,
  title          = "Synthetic draggable map"
)

The same annotation types available in the interactive helper work in static output:

notes <- as_drag_annotations(data.frame(
  label_id = "east-note",
  region   = "East",
  label    = "The East label can become a longer draggable note.",
  x = 210000, y = 120000
), connector = TRUE, connector_type = "squiggle")

render_dragged_map(
  regions,
  region_offsets      = region_offsets,
  region_col          = "region",
  labels              = notes,
  label_offsets       = data.frame(
    label_id = "east-note", region = "East",
    dx_m = 80000, dy_m = 45000
  ),
  connector_linewidth = 0.8,
  connector_linetype  = "dotted",
  connector_endpoint  = "arrow",
  legend_title        = "Region",
  map_background      = "light_grid",
  title               = "Static output with an annotation box"
)

Running examples

Installed example scripts live under system.file("examples", package = "dragmapr"). To exercise the full package surface non-interactively:

source(system.file("examples", "smoke_examples.R", package = "dragmapr"))

Shiny examples launch interactive apps and must be run separately. See the Shiny workflows vignette for a full walkthrough, or run any example directly:

shiny::runApp(system.file("examples", "shiny_draggable_plot.R",   package = "dragmapr"))
shiny::runApp(system.file("examples", "shiny_custom_labels.R",    package = "dragmapr"))
shiny::runApp(system.file("examples", "shiny_draggable_export.R", package = "dragmapr"))
shiny::runApp(system.file("examples", "shiny_spatial_studio.R",   package = "dragmapr"))
shiny::runApp(system.file("examples", "shiny_static_export.R",    package = "dragmapr"))