From 8717d73d924180bec05dfc8d37062652dea78c68 Mon Sep 17 00:00:00 2001
From: Dustin Carlino <dabreegster@gmail.com>
Date: Mon, 6 Nov 2023 13:14:10 +0000
Subject: [PATCH] Make a cost function by LTS, which is really what we want in
 most cases so far

---
 Cargo.lock                            |  1 +
 od2net/src/config.rs                  |  8 +++
 od2net/src/network/create_from_osm.rs |  2 +-
 od2net/src/plugins/cost.rs            | 22 +++++++
 viewer/src/CostFunction.svelte        | 30 ++++++++-
 viewer/src/EdgeCostApp.svelte         | 94 +++++++++++++++------------
 viewer/src/SidebarControls.svelte     | 12 ++--
 viewer/src/common.ts                  |  7 ++
 wasm-od2net/Cargo.toml                |  1 +
 wasm-od2net/src/lib.rs                |  1 +
 10 files changed, 126 insertions(+), 52 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 9b01d89..5c49f3e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1122,6 +1122,7 @@ dependencies = [
  "rstar",
  "serde",
  "serde-wasm-bindgen 0.6.1",
+ "serde_json",
  "wasm-bindgen",
  "web-sys",
 ]
diff --git a/od2net/src/config.rs b/od2net/src/config.rs
index a3e8c75..9223776 100644
--- a/od2net/src/config.rs
+++ b/od2net/src/config.rs
@@ -62,6 +62,14 @@ pub enum CostFunction {
     Distance,
     /// Heavily penalize main roads
     AvoidMainRoads,
+    /// Multiply distance by a factor for each LTS classification
+    ByLTS {
+        lts1: f64,
+        lts2: f64,
+        lts3: f64,
+        lts4: f64,
+        // TODO Incorporate nearby_amenities. Maybe a list of ranges and then a multiplier?
+    },
     /// Multiply distance by a factor based on the OSM highway tag. If the type isn't present, it
     /// won't be allowed at all.
     OsmHighwayType(HashMap<String, f64>),
diff --git a/od2net/src/network/create_from_osm.rs b/od2net/src/network/create_from_osm.rs
index 4e013d5..e7253d5 100644
--- a/od2net/src/network/create_from_osm.rs
+++ b/od2net/src/network/create_from_osm.rs
@@ -173,7 +173,7 @@ fn scrape_elements(
                     greenspace_polygons.push(polygon);
                 }
 
-                // TODO Improve filtering
+                // Include everything here, and let LTS::NotAllowed later filter some out
                 if tags.has("highway") {
                     ways.insert(
                         way.id(),
diff --git a/od2net/src/plugins/cost.rs b/od2net/src/plugins/cost.rs
index 79e067d..a603f61 100644
--- a/od2net/src/plugins/cost.rs
+++ b/od2net/src/plugins/cost.rs
@@ -17,6 +17,15 @@ pub fn calculate_batch(cost: &CostFunction, input_batch: Vec<&Edge>) -> Vec<Opti
             .into_iter()
             .map(|e| osm_highway_type(e, weights))
             .collect(),
+        CostFunction::ByLTS {
+            lts1,
+            lts2,
+            lts3,
+            lts4,
+        } => input_batch
+            .into_iter()
+            .map(|e| by_lts(e, *lts1, *lts2, *lts3, *lts4))
+            .collect(),
         CostFunction::ExternalCommand(command) => external_command(command, input_batch).unwrap(),
     }
 }
@@ -57,6 +66,19 @@ fn osm_highway_type(edge: &Edge, weights: &HashMap<String, f64>) -> Option<usize
     Some((weight * edge.length_meters).round() as usize)
 }
 
+fn by_lts(edge: &Edge, lts1: f64, lts2: f64, lts3: f64, lts4: f64) -> Option<usize> {
+    let weight = match edge.lts {
+        LTS::NotAllowed => {
+            return None;
+        }
+        LTS::LTS1 => lts1,
+        LTS::LTS2 => lts2,
+        LTS::LTS3 => lts3,
+        LTS::LTS4 => lts4,
+    };
+    Some((weight * edge.length_meters).round() as usize)
+}
+
 fn external_command(command: &str, input_batch: Vec<&Edge>) -> Result<Vec<Option<usize>>> {
     let args: Vec<&str> = command.split(" ").collect();
 
diff --git a/viewer/src/CostFunction.svelte b/viewer/src/CostFunction.svelte
index e9382b4..fc5a299 100644
--- a/viewer/src/CostFunction.svelte
+++ b/viewer/src/CostFunction.svelte
@@ -1,9 +1,18 @@
 <script lang="ts">
-  // TODO Widget's broken, bind:value not working
+  import { ltsNames } from "./common";
+
   export let cost;
 
   // TODO Maybe not in sync with what's passed in initially
   let costChoice = "Distance";
+
+  let ltsWeights = {
+    lts1: 1.0,
+    lts2: 1.0,
+    lts3: 1.0,
+    lts4: 1.0,
+  };
+
   // TODO Let people add/remove choices
   let osmHighwayWeights = {};
   for (let key of [
@@ -34,6 +43,8 @@
   function setCost(costChoice) {
     if (costChoice == "OsmHighwayType") {
       cost = { OsmHighwayType: osmHighwayWeights };
+    } else if (costChoice == "ByLTS") {
+      cost = { ByLTS: ltsWeights };
     } else {
       cost = costChoice;
     }
@@ -47,6 +58,7 @@
     <select bind:value={costChoice}>
       <option value="Distance">Distance</option>
       <option value="AvoidMainRoads">Avoid main roads</option>
+      <option value="ByLTS">Weight per LTS</option>
       <option value="OsmHighwayType">Set a weight per OSM highway type</option>
     </select>
   </label>
@@ -67,4 +79,20 @@
       </li>
     {/each}
   </ul>
+{:else if costChoice == "ByLTS"}
+  <ul>
+    {#each ["lts1", "lts2", "lts3", "lts4"] as key}
+      <li>
+        <label
+          >{ltsNames[key]}<input
+            type="number"
+            min="1.0"
+            step="0.1"
+            bind:value={ltsWeights[key]}
+            on:change={() => (cost = cost)}
+          /></label
+        >
+      </li>
+    {/each}
+  </ul>
 {/if}
diff --git a/viewer/src/EdgeCostApp.svelte b/viewer/src/EdgeCostApp.svelte
index 6b691fc..4c96a22 100644
--- a/viewer/src/EdgeCostApp.svelte
+++ b/viewer/src/EdgeCostApp.svelte
@@ -10,7 +10,13 @@
     Popup,
   } from "svelte-maplibre";
   import init, { JsNetwork } from "wasm-od2net";
-  import { colorByLts, colors, colorScale, makeColorRamp } from "./common";
+  import {
+    colorByLts,
+    colors,
+    colorScale,
+    ltsNames,
+    makeColorRamp,
+  } from "./common";
   import CostFunction from "./CostFunction.svelte";
   import Header from "./Header.svelte";
   import Layout from "./Layout.svelte";
@@ -131,49 +137,51 @@
       Open a <i>.bin</i> network file or an <i>.osm.pbf</i>
       <input bind:this={fileInput} on:change={fileLoaded} type="file" />
     </label>
-    <hr />
-    <div>
-      <label>
-        Color edges by:
-        <select bind:value={colorBy}>
-          <option value="lts">LTS</option>
-          <option value="cost">Edge cost (relative to length)</option>
-          <option value="nearby_amenities">Nearby amenities</option>
-        </select>
-      </label>
-    </div>
-    {#if colorBy == "lts"}
-      <Legend
-        rows={[
-          [
-            `LTS 1 - suitable for children: ${percentByLength[1].toFixed(0)}%`,
-            colors.lts1,
-          ],
-          [
-            `LTS 2 - low stress: ${percentByLength[2].toFixed(0)}%`,
-            colors.lts2,
-          ],
-          [
-            `LTS 3 - medium stress: ${percentByLength[3].toFixed(0)}%`,
-            colors.lts3,
-          ],
-          [
-            `LTS 4 - high stress: ${percentByLength[4].toFixed(0)}%`,
-            colors.lts4,
-          ],
-        ]}
-      />
-      <p>
-        Note: LTS model from <a
-          href="https://github.com/BikeOttawa/stressmodel/blob/master/stressmodel.js"
-          target="_blank">BikeOttawa</a
-        >
-      </p>
-    {:else}
-      <SequentialLegend {colorScale} limits={limitsFor(colorBy)} />
+    {#if network}
+      <hr />
+      <div>
+        <label>
+          Color edges by:
+          <select bind:value={colorBy}>
+            <option value="lts">LTS</option>
+            <option value="cost">Edge cost (relative to length)</option>
+            <option value="nearby_amenities">Nearby amenities</option>
+          </select>
+        </label>
+      </div>
+      {#if colorBy == "lts"}
+        <Legend
+          rows={[
+            [
+              `${ltsNames.lts1}: ${percentByLength[1].toFixed(0)}%`,
+              colors.lts1,
+            ],
+            [
+              `${ltsNames.lts2}: ${percentByLength[2].toFixed(0)}%`,
+              colors.lts2,
+            ],
+            [
+              `${ltsNames.lts3}: ${percentByLength[3].toFixed(0)}%`,
+              colors.lts3,
+            ],
+            [
+              `${ltsNames.lts4}: ${percentByLength[4].toFixed(0)}%`,
+              colors.lts4,
+            ],
+          ]}
+        />
+        <p>
+          Note: LTS model from <a
+            href="https://github.com/BikeOttawa/stressmodel/blob/master/stressmodel.js"
+            target="_blank">BikeOttawa</a
+          >
+        </p>
+      {:else}
+        <SequentialLegend {colorScale} limits={limitsFor(colorBy)} />
+      {/if}
+      <hr />
+      <CostFunction bind:cost />
     {/if}
-    <hr />
-    <CostFunction bind:cost />
   </div>
   <div slot="main" style="position:relative; width: 100%; height: 100vh;">
     <MapLibre
diff --git a/viewer/src/SidebarControls.svelte b/viewer/src/SidebarControls.svelte
index 586c185..a84714d 100644
--- a/viewer/src/SidebarControls.svelte
+++ b/viewer/src/SidebarControls.svelte
@@ -1,5 +1,5 @@
 <script lang="ts">
-  import { colors } from "./common";
+  import { colors, ltsNames } from "./common";
   import Legend from "./Legend.svelte";
   import StreetView from "./StreetView.svelte";
   import ToggleLayer from "./ToggleLayer.svelte";
@@ -57,21 +57,19 @@
 <Legend
   rows={[
     [
-      `LTS 1 - suitable for children: ${total(
-        outputMetadata.total_meters_lts1
-      )}`,
+      `${ltsNames.lts1}: ${total(outputMetadata.total_meters_lts1)}`,
       colors.lts1,
     ],
     [
-      `LTS 2 - low stress: ${total(outputMetadata.total_meters_lts2)}`,
+      `${ltsNames.lts2}: ${total(outputMetadata.total_meters_lts2)}`,
       colors.lts2,
     ],
     [
-      `LTS 3 - medium stress: ${total(outputMetadata.total_meters_lts3)}`,
+      `${ltsNames.lts3}: ${total(outputMetadata.total_meters_lts3)}`,
       colors.lts3,
     ],
     [
-      `LTS 4 - high stress: ${total(outputMetadata.total_meters_lts4)}`,
+      `${ltsNames.lts4}: ${total(outputMetadata.total_meters_lts4)}`,
       colors.lts4,
     ],
   ]}
diff --git a/viewer/src/common.ts b/viewer/src/common.ts
index adf852b..d567576 100644
--- a/viewer/src/common.ts
+++ b/viewer/src/common.ts
@@ -46,3 +46,10 @@ export function makeColorRamp(
 
 // Sequential (low-to-high) color ramp from https://www.ons.gov.uk/census/maps/choropleth
 export let colorScale = ["#CDE594", "#80C6A3", "#1F9EB7", "#186290", "#080C54"];
+
+export let ltsNames = {
+  lts1: "LTS 1 - suitable for children",
+  lts2: "LTS 2 - low stress",
+  lts3: "LTS 3 - medium stress",
+  lts4: "LTS 4 - high stress",
+};
diff --git a/wasm-od2net/Cargo.toml b/wasm-od2net/Cargo.toml
index 4d4deb5..4c0dbf1 100644
--- a/wasm-od2net/Cargo.toml
+++ b/wasm-od2net/Cargo.toml
@@ -17,6 +17,7 @@ log = "0.4.20"
 od2net = { path = "../od2net" }
 rstar = "0.11.0"
 serde = "1.0.188"
+serde_json = "1.0.105"
 serde-wasm-bindgen = "0.6.0"
 wasm-bindgen = "0.2.87"
 web-sys = { version = "0.3.64", features = ["console"] }
diff --git a/wasm-od2net/src/lib.rs b/wasm-od2net/src/lib.rs
index e73a438..776fa35 100644
--- a/wasm-od2net/src/lib.rs
+++ b/wasm-od2net/src/lib.rs
@@ -150,6 +150,7 @@ impl JsNetwork {
     #[wasm_bindgen(js_name = updateCostFunction)]
     pub fn update_cost_function(&mut self, input: JsValue) -> Result<(), JsValue> {
         let cost: CostFunction = serde_wasm_bindgen::from_value(input)?;
+        info!("Changing cost to {}", serde_json::to_string(&cost).map_err(err_to_js)?);
         self.last_cost = cost;
         self.network.recalculate_cost(&self.last_cost);
         // Doesn't touch the CH, because this is only meant to be used in the edge cost app, which