docs: add as_points tutorial

.github/workflows/execute.yaml

@@ -64,6 +64,9 @@ jobs:
           else
             nbs=$(find tutorials examples -name "*.ipynb" -not -path "*/.ipynb_checkpoints/*" 2>/dev/null || true)
           fi
+          # Notebooks whose datasets are too large for CI (multi-GB downloads):
+          # their committed outputs are trusted and never re-executed here.
+          nbs=$(printf '%s\n' "$nbs" | grep -vxF 'tutorials/as_points.ipynb' || true)
           if [ -z "$nbs" ]; then
             echo "No notebooks to execute."
           else

tutorials/index.md

@@ -45,6 +45,16 @@ selection for images, and the `datashader` backend for large collections
 of shapes and points.
 :::
 
+:::{grid-item-card} Rendering elements as points
+:link: /notebooks/tutorials/as_points
+:link-type: doc
+:img-top: /notebooks/_static/img/as_points.png
+
+Draw shapes and label masks as one dot per centroid with `as_points=True`
+— a fast overview that trades geometry for speed, including the matplotlib
+→ datashader switch above ~50k elements.
+:::
+
 :::{grid-item-card} Scalebars
 :link: /notebooks/tutorials/scalebars
 :link-type: doc
@@ -65,5 +75,6 @@ getting_started
 color_and_palette
 multi_panel_color
 performance
+as_points
 scalebars
 ```