From 9fc05f5e35ebfc957d392a1d8cbaf8b4e6c660b7 Mon Sep 17 00:00:00 2001
From: Tom MacWright <tom@macwright.org>
Date: Tue, 8 Jan 2013 16:07:16 -0500
Subject: [PATCH] Zoom-dependent styles, optimize difference algorithm.

---
 css/app.css           |  2 +-
 css/map.css           | 22 ++++++++++++++++++++++
 js/id/renderer/map.js | 12 +++++++++---
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/css/app.css b/css/app.css
index 9d203e660..9edceb57c 100644
--- a/css/app.css
+++ b/css/app.css
@@ -8,7 +8,7 @@ body {
     color:#222;
     /* text-rendering: optimizeLegibility;  */
     -webkit-font-smoothing: subpixel-antialiased;
-     }
+}
 
 #iD {
     height: 100%;
diff --git a/css/map.css b/css/map.css
index 5e843b184..707fff169 100644
--- a/css/map.css
+++ b/css/map.css
@@ -34,6 +34,28 @@ circle.fill {
     transform:scale(1, 1);
 }
 
+svg[data-zoom="16"] g.vertex circle.stroke,
+svg[data-zoom="16"] g.vertex circle.fill {
+    -webkit-transform:scale(0.6, 0.6);
+    -moz-transform:scale(0.6, 0.6);
+    transform:scale(0.6, 0.6);
+}
+
+svg[data-zoom="17"] g.vertex circle.stroke,
+svg[data-zoom="17"] g.vertex circle.fill {
+    -webkit-transform:scale(0.7, 0.7);
+    -moz-transform:scale(0.7, 0.7);
+    transform:scale(0.7, 0.7);
+}
+
+svg[data-zoom="16"] path.casing.tag-highway {
+    stroke-width:6;
+}
+
+svg[data-zoom="16"] path.stroke.tag-highway {
+    stroke-width:4;
+}
+
 g.vertex circle.stroke {
     fill:#333;
 }
diff --git a/js/id/renderer/map.js b/js/id/renderer/map.js
index 11b6e2e8a..e15b86d88 100644
--- a/js/id/renderer/map.js
+++ b/js/id/renderer/map.js
@@ -78,9 +78,14 @@ iD.Map = function() {
             var only = {};
             difference.forEach(function buildDifference(id) {
                 only[id] = graph.fetch(id);
-                graph.parentWays(id).forEach(function buildOnly(parent) {
-                    only[parent.id] = graph.fetch(parent.id);
-                });
+                if (typeof only[id].type === 'node') {
+                    graph.parentWays(id).forEach(function buildOnly(parent) {
+                        // Don't re-fetch parents
+                        if (only[parent.id] === undefined) {
+                            only[parent.id] = graph.fetch(parent.id);
+                        }
+                    });
+                }
             });
             all = _.compact(_.values(only));
             filter = function(d) { return d.accuracy ? d.way in only : d.id in only; };
@@ -317,6 +322,7 @@ iD.Map = function() {
 
     function redraw(difference) {
         dispatch.move(map);
+        surface.attr('data-zoom', ~~map.zoom());
         tilegroup.call(background);
         if (map.zoom() > 16) {
             connection.loadTiles(projection);