Add a new API for showing snappable nodes

CHANGES.md

@@ -7,10 +7,13 @@ changes.
 
 ## Unreleased
 
+## 0.4.1
+
 - Removed `fetchWithProgress`, which is a general-purpose utility method that
   should come from another library
 - Improved the tool that makes graphs from GeoJSON files by splitting
   LineStrings that touch at interior points
+- Added `debugSnappableNodes` as a faster alternative to `debugRenderGraph`
 
 ## 0.4.0
 

route-snapper/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "route-snapper"
-version = "0.4.0"
+version = "0.4.1"
 edition = "2021"
 description = "Draw routes in MapLibre snapped to a street network using client-side routing"
 repository = "https://github.com/dabreegster/route_snapper"

route-snapper/src/lib.rs

@@ -718,6 +718,18 @@ impl JsRouteSnapper {
         serde_json::to_string_pretty(&gj).unwrap()
     }
 
+    /// Render the graph as GeoJSON points, for helping the user understand the snappable nodes.
+    #[wasm_bindgen(js_name = debugSnappableNodes)]
+    pub fn debug_snappable_nodes(&self) -> String {
+        let mut features = Vec::new();
+        for pt in &self.router.map.nodes {
+            features.push(Feature::from(Geometry::from(&Point::from(*pt))));
+        }
+        let gj =
+            geojson::GeoJson::from(features.into_iter().collect::<geojson::FeatureCollection>());
+        serde_json::to_string(&gj).unwrap()
+    }
+
     #[wasm_bindgen(js_name = routeNameForWaypoints)]
     pub fn route_name_for_waypoints(&self, raw_waypoints: JsValue) -> Result<String, JsValue> {
         let waypoints: Vec<RouteWaypoint> = serde_wasm_bindgen::from_value(raw_waypoints)?;

user_guide.md

@@ -154,6 +154,7 @@ If you're using the WASM API directly, the best reference is currently [the code
     - A numeric `undo_length`
 - `toggleSnapMode` attempts to switch between snapping and freehand drawing. It may not succeed.
 - `addSnappedWaypoint` adds a new waypoint to the end of the route, snapping to the nearest node. It's useful for clients to hook up a geocoder and add a point by address. Unsupported in area mode.
+- `debugSnappableNodes` returns a FeatureCollection of Points with no properties, for showing the user all snappable nodes
 
 ### MapLibre gotchas