Draw arrows to show entrances/exits to a LTN.

(and rename Line::reverse for consistency with PolyLine)

game/src/ltn/mod.rs

@@ -1,6 +1,6 @@
 use std::collections::BTreeSet;
 
-use geom::{Distance, Line};
+use geom::{Distance, Line, PolyLine, Polygon};
 use map_gui::tools::{CityPicker, ColorDiscrete};
 use map_gui::ID;
 use map_model::{IntersectionID, Map, Road, RoadID};
@@ -242,7 +242,6 @@ impl Neighborhood {
             vec![
                 ("interior", Color::BLUE.alpha(0.8)),
                 ("perimeter", Color::hex("#40B5AD").alpha(0.8)),
-                ("border", Color::CYAN.alpha(0.8)),
                 ("rat-run", Color::RED.alpha(0.8)),
                 ("modal filter", Color::GREEN),
             ],
@@ -257,10 +256,37 @@ impl Neighborhood {
             colorer.add_r(*r, "perimeter");
         }
         for i in &self.borders {
-            colorer.add_i(*i, "border");
+            // TODO These should have a higher z-order than rat runs
+            let arrow = self.border_arrow(&app.primary.map, *i);
+            colorer.unzoomed.push(Color::PURPLE, arrow.clone());
+            colorer.zoomed.push(Color::PURPLE, arrow.clone());
         }
         colorer.build(ctx)
     }
+
+    fn border_arrow(&self, map: &Map, i: IntersectionID) -> Polygon {
+        assert!(self.borders.contains(&i));
+        // Multiple interior roads could connect to one border, but let's just use one (the common
+        // case anyway)
+        let road = map.get_r(
+            *map.get_i(i)
+                .roads
+                .iter()
+                .find(|r| self.interior.contains(r))
+                .unwrap(),
+        );
+        let line = if road.dst_i == i {
+            road.center_pts.last_line()
+        } else {
+            road.center_pts.first_line().reversed()
+        };
+        PolyLine::must_new(vec![
+            line.pt2(),
+            line.pt2()
+                .project_away(Distance::meters(30.0), line.angle()),
+        ])
+        .make_double_arrow(Distance::meters(5.0), geom::ArrowCap::Triangle)
+    }
 }
 
 impl RatRun {

geom/src/line.rs

@@ -142,7 +142,7 @@ impl Line {
     }
 
     /// Returns a reversed line segment
-    pub fn reverse(&self) -> Line {
+    pub fn reversed(&self) -> Line {
         Line::must_new(self.pt2(), self.pt1())
     }
 

map_gui/src/render/intersection.rs

@@ -354,7 +354,7 @@ fn calculate_corner_curbs(i: &Intersection, map: &Map) -> Vec<Polygon> {
                     let first_line = l2.first_line().shift_either_direction(width);
                     pts.push(first_line.pt1());
                     pts.push(first_line.unbounded_dist_along(thickness));
-                    let last_line = l1.last_line().shift_either_direction(width).reverse();
+                    let last_line = l1.last_line().shift_either_direction(width).reversed();
                     pts.insert(0, last_line.pt1());
                     pts.insert(0, last_line.unbounded_dist_along(thickness));
                     PolyLine::deduping_new(pts).ok()
@@ -375,7 +375,7 @@ fn calculate_corner_curbs(i: &Intersection, map: &Map) -> Vec<Polygon> {
                     .first_line()
                     .shift_either_direction(direction * shift(l2.width));
                 if let Ok(pl) = PolyLine::deduping_new(vec![
-                    last_line.reverse().unbounded_dist_along(thickness),
+                    last_line.reversed().unbounded_dist_along(thickness),
                     last_line.pt2(),
                     first_line.pt1(),
                     first_line.unbounded_dist_along(thickness),
@@ -409,7 +409,7 @@ fn calculate_border_arrows(i: &Intersection, r: &Road, map: &Map) -> Vec<Polygon
     if !i.outgoing_lanes.is_empty() {
         let (line, width) = if r.dst_i == i.id {
             (
-                center.last_line().shift_left(width_back / 2.0).reverse(),
+                center.last_line().shift_left(width_back / 2.0).reversed(),
                 width_back,
             )
         } else {
@@ -429,7 +429,7 @@ fn calculate_border_arrows(i: &Intersection, r: &Road, map: &Map) -> Vec<Polygon
     if !i.incoming_lanes.is_empty() {
         let (line, width) = if r.dst_i == i.id {
             (
-                center.last_line().shift_right(width_fwd / 2.0).reverse(),
+                center.last_line().shift_right(width_fwd / 2.0).reversed(),
                 width_fwd,
             )
         } else {

map_model/src/make/turns.rs

@@ -232,7 +232,7 @@ fn curvey_turn(src: &Lane, dst: &Lane) -> Result<PolyLine> {
     // The control points are straight out/in from the source/destination lanes, so
     // that the car exits and enters at the same angle as the road.
     let src_line = src.last_line();
-    let dst_line = dst.first_line().reverse();
+    let dst_line = dst.first_line().reversed();
 
     // TODO Tune the 5.0 and pieces
     let pt1 = src.last_pt();

map_model/src/objects/lane.rs

@@ -291,7 +291,7 @@ impl Lane {
     /// pt2 will be endpoint
     pub fn end_line(&self, i: IntersectionID) -> Line {
         if i == self.src_i {
-            self.first_line().reverse()
+            self.first_line().reversed()
         } else if i == self.dst_i {
             self.last_line()
         } else {

sim/src/mechanics/walking.rs

@@ -743,7 +743,7 @@ impl Pedestrian {
             PedState::EnteringParkingLot(pl, ref time_int) => {
                 let line = &map.get_pl(pl).sidewalk_line;
                 (
-                    line.reverse()
+                    line.reversed()
                         .percent_along(time_int.percent(now))
                         .unwrap_or_else(|| line.pt1()),
                     line.angle().opposite(),