feat(map): scale propagation ranges with antenna height

Antenna height now drives typical/extended/exceptional range estimates
and viewshed max range via a sqrt(h_m/10) factor clamped to [0.6, 2.0].
Baseline 33 ft matches the existing defaults. Changing the height input
now pushes update_band_info and refreshes the clicked point's detail
panel plus viewshed so the range-estimate line and coverage shape track
the user's actual station height.

assets/js/propagation_map_hook.ts

@@ -739,14 +739,21 @@ export const PropagationMap: Record<string, unknown> & {
       this.bandInfo = band_info
 
       // Viewshed depends on freq + score-derived range, so recompute it when
-      // the band changes if a point is still selected. update_scores already
-      // handles the heatmap, reach polygon, and detail panel refresh.
+      // the band changes or antenna height moves if a point is still selected.
+      // Also re-request point_detail so the popup's range-estimate line picks
+      // up the updated typical/extended/exceptional ranges. update_scores
+      // (on band change) already refreshes the polygon/heatmap; for
+      // antenna-height changes the polygon is height-independent today.
       if (this.clickedLatLng && this.detailPanel && this.detailPanel.style.display !== "none") {
         this.viewshedLoading = true
         this.pushEvent("compute_viewshed", {
           lat: this.clickedLatLng[0],
           lon: this.clickedLatLng[1]
         })
+        this.pushEvent("point_detail", {
+          lat: this.clickedLatLng[0],
+          lon: this.clickedLatLng[1]
+        })
       }
     })
 

lib/microwaveprop_web/live/map_live.ex

@@ -159,7 +159,9 @@ defmodule MicrowavepropWeb.MapLive do
       |> assign(selected_band: band, valid_times: valid_times, selected_time: selected_time)
       |> LiveStash.stash_assigns([:selected_band, :selected_time])
       |> push_event("update_scores", %{scores: scores})
-      |> push_event("update_band_info", %{band_info: band_info(band)})
+      |> push_event("update_band_info", %{
+        band_info: band_info(band, socket.assigns.antenna_height_ft)
+      })
       |> push_timeline()
 
     {:noreply, socket}
@@ -199,7 +201,14 @@ defmodule MicrowavepropWeb.MapLive do
         _ -> 8
       end
 
-    {:noreply, assign(socket, :antenna_height_ft, height)}
+    socket =
+      socket
+      |> assign(:antenna_height_ft, height)
+      |> push_event("update_band_info", %{
+        band_info: band_info(socket.assigns.selected_band, height)
+      })
+
+    {:noreply, socket}
   end
 
   def handle_event("toggle_grid", _params, socket) do
@@ -274,7 +283,7 @@ defmodule MicrowavepropWeb.MapLive do
         _ -> 50
       end
 
-    max_range_km = score_range_km(score, band_config)
+    max_range_km = score_range_km(score, band_config, socket.assigns.antenna_height_ft)
 
     socket =
       start_async(socket, :viewshed, fn ->
@@ -433,29 +442,47 @@ defmodule MicrowavepropWeb.MapLive do
     Enum.min_by(times, fn t -> abs(DateTime.diff(t, now)) end)
   end
 
-  defp score_range_km(score, config) do
-    cond do
-      score >= 80 -> config.exceptional_range_km
-      score >= 65 -> config.extended_range_km
-      score >= 50 -> config.typical_range_km
-      score >= 33 -> round(config.typical_range_km * 0.6)
-      true -> round(config.typical_range_km * 0.3)
-    end
+  defp score_range_km(score, config, ant_height_ft) do
+    factor = height_factor(ant_height_ft)
+
+    base =
+      cond do
+        score >= 80 -> config.exceptional_range_km
+        score >= 65 -> config.extended_range_km
+        score >= 50 -> config.typical_range_km
+        score >= 33 -> round(config.typical_range_km * 0.6)
+        true -> round(config.typical_range_km * 0.3)
+      end
+
+    round(base * factor)
   end
 
-  defp band_info(band_mhz) do
+  defp band_info(band_mhz, ant_height_ft) do
     config = BandConfig.get(band_mhz)
+    factor = height_factor(ant_height_ft)
 
     %{
       band_label: config.label,
-      typical_range_km: config.typical_range_km,
-      extended_range_km: config.extended_range_km,
-      exceptional_range_km: config.exceptional_range_km,
+      typical_range_km: round(config.typical_range_km * factor),
+      extended_range_km: round(config.extended_range_km * factor),
+      exceptional_range_km: round(config.exceptional_range_km * factor),
       humidity_effect: to_string(config.humidity_effect),
-      freq_mhz: config.freq_mhz
+      freq_mhz: config.freq_mhz,
+      antenna_height_ft: ant_height_ft
     }
   end
 
+  # Scales effective range with antenna height. Baseline 33 ft (~10 m) = 1.0;
+  # scales as sqrt(h_m / 10) because radio horizon scales as sqrt(height).
+  # Clamped to [0.6, 2.0] to avoid silly extremes at 0 ft and very tall towers.
+  defp height_factor(ant_height_ft) when is_number(ant_height_ft) do
+    h_m = max(ant_height_ft, 3) * 0.3048
+    factor = :math.sqrt(h_m / 10.0)
+    factor |> max(0.6) |> min(2.0)
+  end
+
+  defp height_factor(_), do: 1.0
+
   defp selected_label(bands, selected_band) do
     case Enum.find(bands, &(&1.freq_mhz == selected_band)) do
       nil -> "Select Band"
@@ -555,7 +582,7 @@ defmodule MicrowavepropWeb.MapLive do
           phx-hook="PropagationMap"
           phx-update="ignore"
           data-scores={@initial_scores_json}
-          data-band-info={Jason.encode!(band_info(@selected_band))}
+          data-band-info={Jason.encode!(band_info(@selected_band, @antenna_height_ft))}
           data-valid-times={
             Jason.encode!(
               Enum.map(@valid_times, fn t ->

test/microwaveprop_web/live/map_live_test.exs

@@ -99,6 +99,20 @@ defmodule MicrowavepropWeb.MapLiveTest do
       html = render_change(lv, "set_antenna_height", %{"height_ft" => "20"})
       assert html =~ ~s(value="20")
     end
+
+    test "pushes update_band_info with height-scaled ranges", %{conn: conn} do
+      {:ok, lv, _html} = live(conn, ~p"/map")
+
+      baseline = render_change(lv, "set_antenna_height", %{"height_ft" => "33"})
+      assert_push_event(lv, "update_band_info", %{band_info: %{typical_range_km: baseline_range}})
+      assert baseline =~ ~s(value="33")
+
+      tall = render_change(lv, "set_antenna_height", %{"height_ft" => "100"})
+      assert_push_event(lv, "update_band_info", %{band_info: %{typical_range_km: tall_range}})
+      assert tall =~ ~s(value="100")
+
+      assert tall_range > baseline_range
+    end
   end
 
   describe "compute_viewshed" do