Add missing oneway arrows for tracks and paths (#3614)

* Add oneway arrows for tracks and paths

Fixed rendering of arrows on footways: these will always use the footway color, rather than changing if there is designated=bicycle or designated=bridleway
Fix bridleway arrow color: based on brideway color instead of track color now.
Fix merge conflict in project.mml

* Darken steps and bridleway oneway arrows

Steps 50%, bridleway 25%

* Darken arrows for all paths and track

* Move path oneway arrows to right of line

Also check for oneway = -1 to make sure text and arrows are on the correct side of the path

Fix whitespace & simplify oneway arrow code for paths

* Change path oneway arrow to unicode text with halo

* Change path arrow to U+1f816 "Rightwards arrow with equilateral arrowhead"

* Add back missing "construction" in paths-text-name

This was unintentionally removed and would prevent the rendering of name labels for under-constructions paths

* Revert text-dy changes for oneway

Simplify current PR by removing the changes to text-dy for path name labels, which had been intended to make sure that the text was always on the same side as the arrows if these were rendered next to the line

project.mml

@@ -1996,6 +1996,7 @@ Layer:
     properties:
       minzoom: 13
   - id: paths-text-name
+    class: directions
     geometry: linestring
     <<: *extents
     Datasource:
@@ -2005,10 +2006,19 @@ Layer:
             way,
             highway,
             construction,
-            name
+            name,
+            CASE
+              WHEN oneway IN ('yes', '-1') THEN oneway
+              WHEN junction IN ('roundabout') AND (oneway IS NULL OR NOT oneway IN ('no', 'reversible')) THEN 'yes'
+              ELSE NULL
+            END AS oneway,
+            horse,
+            bicycle
           FROM planet_osm_line
           WHERE highway IN ('bridleway', 'footway', 'cycleway', 'path', 'track', 'steps', 'construction')
-            AND name IS NOT NULL
+            AND (name IS NOT NULL
+              OR oneway IN ('yes', '-1')
+              OR junction IN ('roundabout'))
         ) AS paths_text_name
     properties:
       minzoom: 15

roads.mss

@@ -291,8 +291,8 @@
 @footway-oneway-arrow-color:      darken(@footway-fill, 35%);
 @steps-oneway-arrow-color:        darken(@steps-fill, 35%);
 @cycleway-oneway-arrow-color:     darken(@cycleway-fill, 25%);
-@track-oneway-arrow-color:        darken(@track-fill, 15%);
-@bridleway-oneway-arrow-color:    darken(@track-fill, 10%);
+@track-oneway-arrow-color:        darken(@track-fill, 10%);
+@bridleway-oneway-arrow-color:    darken(@bridleway-fill, 15%);
 
 // Shield’s line wrap is based on OpenStreetMap data and not on line-wrap-width,
 // but lines are typically rather short, so we use narrow line spacing.
@@ -3355,19 +3355,12 @@ tertiary is rendered from z10 and is not included in osm_planet_roads. */
     [highway = 'road'],
     [highway = 'service'],
     [highway = 'pedestrian'],
-    [highway = 'raceway'],
-    [highway = 'cycleway'],
-    [highway = 'footway'],
-    [highway = 'path'],
-    [highway = 'steps'],
-    [highway = 'track'],
-    [highway = 'bridleway'] {
+    [highway = 'raceway'] {
       [oneway = 'yes'],
       [oneway = '-1'] {
         marker-placement: line;
         marker-spacing: 180;
         marker-max-error: 0.5;
-
         marker-file: url('symbols/oneway.svg');
         [oneway = '-1'] {
           marker-file: url('symbols/oneway-reverse.svg');
@@ -3408,32 +3401,62 @@ tertiary is rendered from z10 and is not included in osm_planet_roads. */
         [highway = 'raceway'] {
           marker-fill: @raceway-oneway-arrow-color;
         }
-        [highway = 'footway'],
+      }
+    }
+
+    [highway = 'steps'],
+    [highway = 'cycleway'],
+    [highway = 'footway'],
+    [highway = 'path'],
+    [highway = 'track'],
+    [highway = 'bridleway'] {
+      [oneway = 'yes'],
+      [oneway = '-1'] {
+        text-name: "'🠖'";
+        text-size: 15;
+        text-clip: false;
+        text-spacing: 180;
+        text-placement: line;
+        text-halo-fill: @standard-halo-fill;
+        text-halo-radius: 1.5;
+        text-margin: 2;
+        text-dy: 3;
+        text-upright: right;
+        text-vertical-alignment: middle;
+        text-face-name: @book-fonts;
+        [oneway = '-1'] {
+          text-upright: left;
+          text-dy: -3;
+        }
+        [highway = 'footway'] {
+          text-fill: @footway-oneway-arrow-color;
+        }
         [highway = 'path'] {
-          marker-fill: @footway-oneway-arrow-color;
+          text-fill: @footway-oneway-arrow-color;
           [horse = 'designated'] {
-            marker-fill: @bridleway-oneway-arrow-color;
+            text-fill: @bridleway-oneway-arrow-color;
           }
           [bicycle = 'designated'] {
-            marker-fill: @cycleway-oneway-arrow-color;
+            text-fill: @cycleway-oneway-arrow-color;
           }
         }
         [highway = 'steps'] {
-          marker-fill: @steps-oneway-arrow-color;
+          text-fill: @steps-oneway-arrow-color;
         }
         [highway = 'cycleway'] {
-          marker-fill: @cycleway-oneway-arrow-color;
+          text-fill: @cycleway-oneway-arrow-color;
         }
         [highway = 'track'] {
-          marker-fill: @track-oneway-arrow-color;
+          text-fill: @track-oneway-arrow-color;
         }
         [highway = 'bridleway'] {
-          marker-fill: @bridleway-oneway-arrow-color;
+          text-fill: @bridleway-oneway-arrow-color;
         }
       }
     }
   }
 }
+
 #railways-text-name {
   /* Mostly started from z17. */
   [railway = 'rail'],