Add Heatmap layer

Author: Stefan Kuethe

examples/standalone/layers/heatmap-layer.py

@@ -0,0 +1,3 @@
+import openlayers as ol
+
+from openlayers.models.layers import HeatmapLayer

marimo/earthquakes-heatmap.py

@@ -0,0 +1,77 @@
+
+
+import marimo
+
+__generated_with = "0.13.2"
+app = marimo.App(width="medium")
+
+
+@app.cell
+def _():
+    import marimo as mo
+    import openlayers as ol
+    return mo, ol
+
+
+@app.cell
+def _():
+    data = "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_month.geojson"
+    return (data,)
+
+
+@app.cell
+def _(data, ol):
+    vector = ol.VectorLayer(
+        source=ol.VectorSource(url=data)
+    )
+    return (vector,)
+
+
+@app.cell
+def _(data, ol):
+    radius = 8
+    blur = 15
+
+    heatmap = ol.HeatmapLayer(
+        source=ol.VectorSource(url=data),
+        opacity=0.5,
+        weight=["get", "mag"],
+        radius=radius,
+        blur=blur
+    )
+    return blur, heatmap, radius
+
+
+@app.cell
+def _(heatmap, ol, vector):
+    m = ol.MapWidget(layers=[ol.BasemapLayer(), vector, heatmap])
+    m.add_tooltip()
+    return (m,)
+
+
+@app.cell
+def _(m):
+    m
+    return
+
+
+@app.cell(hide_code=True)
+def _(heatmap, m, mo, radius):
+    mo.ui.slider(start=0, stop=20, step=1, value=radius, label="radius", on_change=lambda r: m.add_layer_call(heatmap.id, "setRadius", r))
+
+    return
+
+
+@app.cell(hide_code=True)
+def _(blur, heatmap, m, mo):
+    mo.ui.slider(start=0, stop=30, step=1, value=blur, label="blur", on_change=lambda b: m.add_layer_call(heatmap.id, "setBlur", b))
+    return
+
+
+@app.cell
+def _():
+    return
+
+
+if __name__ == "__main__":
+    app.run()

src/openlayers/layers.py

@@ -11,6 +11,7 @@
     WebGLTileLayer,
     WebGLVectorLayer,
     WebGLVectorTileLayer,
+    HeatmapLayer,
 )
 
 __all__ = [
@@ -22,4 +23,5 @@
     "VectorTileLayer",
     "WebGLVectorTileLayer",
     "VectorImageLayer",
+    "HeatmapLayer",
 ]

src/openlayers/models/layers.py

@@ -83,6 +83,12 @@ class WebGLTileLayer(Layer):
     style: dict | None = None
 
 
+class HeatmapLayer(Layer):
+    radius: int | list | None = 8
+    blur: int | list | None = 15
+    weight: str | list | None = "weight"
+
+
 # --- Layer type
 LayerT = Union[
     Layer,
@@ -93,4 +99,5 @@ class WebGLTileLayer(Layer):
     VectorTileLayer,
     WebGLVectorTileLayer,
     VectorImageLayer,
+    HeatmapLayer,
 ]