drawing border nodes differently

docs/design/maps.md

@@ -282,3 +282,5 @@ can begin or end.
 	- manually marking them?
 - draw the FSM for cars/peds
 	- trips starting/ending at border nodes short-circuit some steps
+
+What about border nodes where the sidewalk can cross over, but the driving lane leads nowhere?

editor/src/render/intersection.rs

@@ -19,6 +19,7 @@ pub struct DrawIntersection {
     sidewalk_corners: Vec<Polygon>,
     center: Pt2D,
     has_traffic_signal: bool,
+    is_border: bool,
     should_draw_stop_sign: bool,
 }
 
@@ -36,6 +37,7 @@ impl DrawIntersection {
             crosswalks: calculate_crosswalks(inter.id, map),
             sidewalk_corners: calculate_corners(inter.id, map),
             has_traffic_signal: inter.has_traffic_signal,
+            is_border: inter.is_border(map),
             should_draw_stop_sign: !inter.has_traffic_signal && !inter.is_degenerate(),
         }
     }
@@ -85,6 +87,10 @@ impl Renderable for DrawIntersection {
 
     fn draw(&self, g: &mut GfxCtx, opts: RenderOptions, ctx: Ctx) {
         let color = opts.color.unwrap_or_else(|| {
+            if self.is_border {
+                return ctx.cs.get("border intersection", Color::rgb(50, 205, 50));
+            }
+
             let changed = if let Some(s) = ctx.control_map.traffic_signals.get(&self.id) {
                 s.is_changed()
             } else if let Some(s) = ctx.control_map.stop_signs.get(&self.id) {

map_model/src/intersection.rs

@@ -5,7 +5,7 @@ use dimensioned::si;
 use geom::Pt2D;
 use std::collections::BTreeSet;
 use std::fmt;
-use {LaneID, RoadID, TurnID};
+use {LaneID, Map, RoadID, TurnID};
 
 // TODO reconsider pub usize. maybe outside world shouldnt know.
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
@@ -51,6 +51,16 @@ impl Intersection {
         self.roads.len() == 2
     }
 
+    pub fn is_border(&self, map: &Map) -> bool {
+        // Bias for driving
+        if !self.is_dead_end() {
+            return false;
+        }
+        let has_driving_in = self.incoming_lanes.iter().find(|l| map.get_l(**l).is_driving()).is_some();
+        let has_driving_out = self.outgoing_lanes.iter().find(|l| map.get_l(**l).is_driving()).is_some();
+        has_driving_in != has_driving_out
+    }
+
     pub fn dump_debug(&self) {
         println!("{}", abstutil::to_json(self));
     }