Replace LinearMap with Angle2d in tutorial

Signed-off-by: Avnish Jaltare <avnishjaltare8@gmail.com>

Author: Maximus-08

docs/Project.toml

@@ -42,6 +42,7 @@ NaturalEarth = "436b0209-26ab-4e65-94a9-6526d86fea76"
 Printf = "de0858da-6303-5e67-8744-51eddeeeb8d7"
 Proj = "c94c279d-25a6-4763-9509-64d165bea63e"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
+Rotations = "6038ab10-8711-5258-84ad-4b1120ba62dc"
 Shapefile = "8e980c4a-a4fe-5da2-b3a7-4b4b0353a2f4"
 SortTileRecursiveTree = "746ee33f-1797-42c2-866d-db2fce69d14d"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"

docs/src/tutorials/creating_geometry.md

@@ -20,6 +20,7 @@ using GeoJSON # to load some data
 # Packages for coordinate transformation and projection
 import CoordinateTransformations
 import Proj
+import Rotations
 # Plotting
 using CairoMakie
 using GeoMakie
@@ -113,16 +114,13 @@ plot!(polygon1)
 fig
 ````
 
-We can also rotate a polygon with the same `transform` function. A `LinearMap`
-rotates around the origin.
+We can also rotate a polygon with the same `transform` function. Here we use a
+2D rotation from `Rotations.jl`, which rotates around the origin.
 
 ````@example creating_geometry
 theta = π / 4
-rotation = CoordinateTransformations.LinearMap([
-    cos(theta) -sin(theta)
-    sin(theta) cos(theta)
-]);
-polygon1_rotated_origin = GO.transform(rotation, polygon1);
+rotation = Rotations.Angle2d(theta);
+polygon1_rotated_origin = GO.transform(p -> rotation * p, polygon1);
 
 fig_rotation = Figure()
 ax_origin = Axis(fig_rotation[1, 1]; title = "Rotate around the origin", aspect = DataAspect())
@@ -131,15 +129,15 @@ poly!(ax_origin, polygon1_rotated_origin; color = (:orange, 0.35), strokecolor =
 fig_rotation
 ````
 
-To rotate around a polygon's centroid instead, compose the rotation with
-translations before and after it.
+To rotate around a polygon's centroid instead, rotate each point relative to
+the centroid and then shift it back.
 
 ````@example creating_geometry
 polygon1_centroid = GO.centroid(polygon1)
-rotation_about_centroid = CoordinateTransformations.Translation(polygon1_centroid...) ∘
-    rotation ∘
-    CoordinateTransformations.Translation((-).(polygon1_centroid)...)
-polygon1_rotated_centroid = GO.transform(rotation_about_centroid, polygon1);
+polygon1_rotated_centroid = GO.transform(
+    p -> rotation * (p .- polygon1_centroid) .+ polygon1_centroid,
+    polygon1,
+);
 
 ax_centroid = Axis(fig_rotation[1, 2]; title = "Rotate around the centroid", aspect = DataAspect())
 poly!(ax_centroid, polygon1; color = (:steelblue, 0.5), strokecolor = :steelblue)