Handle some clipping edge cases. #127

streets_reader/src/extract.rs

@@ -1,9 +1,8 @@
 use std::collections::HashMap;
 
-use osm::{NodeID, OsmID, RelationID, WayID};
-
 use abstutil::Tags;
 use geom::{HashablePt2D, Pt2D};
+use osm2streets::osm::{NodeID, OsmID, RelationID, WayID};
 use osm2streets::{osm, Direction, RestrictionType};
 
 use crate::osm_reader::{Node, Relation, Way};

streets_reader/src/lib.rs

@@ -58,7 +58,8 @@ fn extract_osm(
     streets.gps_bounds = doc.gps_bounds.clone().unwrap();
 
     if let Some(pts) = clip_pts {
-        streets.boundary_polygon = Ring::new(streets.gps_bounds.convert(&pts))?.into_polygon();
+        streets.boundary_polygon =
+            Ring::deduping_new(streets.gps_bounds.convert(&pts))?.into_polygon();
         doc.clip(&streets.boundary_polygon);
     } else {
         streets.boundary_polygon = streets.gps_bounds.to_bounds().get_rectangle();

streets_reader/src/osm_reader/clip.rs

@@ -1,5 +1,7 @@
 use geom::{Distance, PolyLine, Polygon};
 
+use osm2streets::osm;
+
 use super::Document;
 
 impl Document {
@@ -21,13 +23,17 @@ impl Document {
         // For line-string ways (not areas), clip them to the boundary. way.pts and way.nodes
         // become out-of-sync.
         for (id, way) in &mut self.ways {
-            // TODO This could just be a cul-de-sac road
-            if way.pts[0] == *way.pts.last().unwrap() {
+            // Only clip roads. Areas need more work.
+            if !way.tags.has_any(vec![osm::HIGHWAY, "railway"]) {
                 continue;
             }
 
+            // Careful. We use unchecked_new because we might be dealing with a loop, but we still
+            // need to dedupe, or we might have invalid line segments.
+            let mut way_pts = way.pts.clone();
+            way_pts.dedup();
             let mut polylines =
-                clip_polyline_to_ring(PolyLine::unchecked_new(way.pts.clone()), boundary_polygon);
+                clip_polyline_to_ring(PolyLine::unchecked_new(way_pts), boundary_polygon);
             // Usually there's just one result
             if polylines.len() == 1 {
                 way.pts = polylines.pop().unwrap().into_points();