[DOCS] [Maps] Add documentation for custom icons (#129530) (#129925)

(cherry picked from commit f32faab)

Co-authored-by: Nick Peihl <[email protected]>

docs/maps/map-settings.asciidoc

@@ -5,6 +5,12 @@
 Maps offers settings that let you configure how a map is displayed.
 To access these settings, click *Map settings* in the application toolbar.
 
+[float]
+[[maps-settings-custom-icons]]
+=== Custom icons
+
+Add, edit, or delete custom icons for the map. Icons added to the map can be used for <<point-style-properties, styling Point features>>.
+
 [float]
 [[maps-settings-display]]
 === Display

docs/maps/vector-style-properties.asciidoc

@@ -61,6 +61,14 @@ Available icons
 [role="screenshot"]
 image::maps/images/maki-icons.png[]
 
+Custom Icons
+
+You can also use your own SVG icon to style Point features in your map. In **Layer settings** open the *icon* dropdown, and click the **Add custom icon** button. For best results, your SVG icon should be monochrome and have limited details. 
+
+Dynamic styling in **Elastic Maps** requires rendering SVG icons as PNGs using a https://en.wikipedia.org/wiki/Signed_distance_function[signed distance function]. As a result, sharp corners and intricate details may not render correctly. Modifying the settings under **Advanced Options** in the **Add custom icon** modal may improve rendering.
+
+Manage your custom icons in <<maps-settings, Map settings>>.
+
 [float]
 [[polygon-style-properties]]
 ==== Polygon style properties