✏️ Add basic drawing capabilities

[raphaelquast]

❗ This is a work-in-progress pull request to add basic drawing capabilities to EOmaps.

• <shape> is the shape to draw... currently there are
  • circle, rectangle, polygon
• kwargs passed to the shape can be used to set the style
  • e.g. fc="r", ec="k", lw=2 etc.

UI currently works as follows:

• first, execute the command to start the drawer
• for circle and rectangle:
  • first LEFT click sets the center (drag mouse to set the radius)
  • RIGHT click aborts the draw
  • MIDDLE click fixes the radius and draws the shape
• for polygon
  • LEFT click to add points to the polygon (drag while hold to continuously add points)
  • RIGHT click aborts the draw
  • MIDDLE click to close the polygon and draw the shape

---

To start drawing, use:

m = Maps()
m.add_feature.preset.coastline()
m.util.draw.<shape>(... kwargs ...)

---

To draw shapes that are saved to a geo-coded shapefile, use: (shapes are automatically saved after draw (e.g. middle-click))

# path to a folder with write-access to store the shapes
save_path = ...

m = Maps()
m.add_feature.preset.coastline()
# initialize a new drawer that saves shapefiles to save_path
p1 = m.util.draw.new_poly(savepath=save_path)

# on next click, start drawing a rectangle
p1.<shape>(... kwargs ...)

these shapes can then be re-loaded to a map with:

m = Maps(Maps.CRS.Mollweide())
m.add_feature.preset.coastline()

gdf = gpd.read_file(save_path)
m.add_gdf(gdf, fc="g", alpha=0.5, lw=1, picker_name="asdf")

# make the shapes clickable
m.cb.pick["asdf"].attach.highlight_geometry(fc="r", alpha=.5)
m.cb.pick["asdf"].attach.annotate(text=lambda ID, **kwargs: f"This is shape {ID}")

[codecov-commenter]

Codecov Report

Merging #90 (6c81297) into dev (30d03c6) will increase coverage by 0.05%. The diff coverage is 78.78%.

@@            Coverage Diff             @@
##              dev      #90      +/-   ##
==========================================
+ Coverage   71.35%   71.40%   +0.05%     
==========================================
  Files          12       12              
  Lines        6518     6540      +22     
==========================================
+ Hits         4651     4670      +19     
- Misses       1867     1870       +3     

Impacted Files	Coverage Δ
eomaps/eomaps.py	67.48% <50.00%> (ø)
eomaps/utilities.py	60.00% <72.22%> (+0.75%)	:arrow_up:
eomaps/helpers.py	73.06% <88.88%> (+0.42%)	:arrow_up:
eomaps/callbacks.py	87.57% <100.00%> (-0.04%)	:arrow_down:

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.