From cf3b96e0226092377bd3aef449e1e5a09d987ce3 Mon Sep 17 00:00:00 2001
From: David Manthey <david.manthey@kitware.com>
Date: Tue, 22 Nov 2016 16:39:48 -0500
Subject: [PATCH] Fix the map jumping at the end of some transitions.

Sometimes, when zooming, the map would jump at the end of the transition.  This was caused by the zoom level reaching its final value, then a last animation frame firing, and asking to recenter the map when the center was already correct.
---
 src/map.js | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/map.js b/src/map.js
index 0e24298322..e4764faa5a 100644
--- a/src/map.js
+++ b/src/map.js
@@ -1109,7 +1109,7 @@ var map = function (arg) {
     }
 
     var defaultOpts = {
-      center: m_this.center(undefined, null),
+      center: undefined,
       zoom: m_this.zoom(),
       rotation: m_this.rotation(),
       duration: 1000,
@@ -1155,8 +1155,8 @@ var map = function (arg) {
       opts.zCoord ? zoom2z(m_transition.start.zoom) : m_transition.start.zoom,
       m_transition.start.rotation
     ], [
-      m_transition.end.center.x,
-      m_transition.end.center.y,
+      m_transition.end.center ? m_transition.end.center.x : m_transition.start.center.x,
+      m_transition.end.center ? m_transition.end.center.y : m_transition.start.center.y,
       opts.zCoord ? zoom2z(m_transition.end.zoom) : m_transition.end.zoom,
       m_transition.end.rotation
     ]);
@@ -1192,8 +1192,10 @@ var map = function (arg) {
       m_transition.time = time - m_transition.start.time;
       if (time >= m_transition.end.time || next) {
         if (!next) {
-          var needZoom = m_zoom !== fix_zoom(m_transition.end.zoom);
-          m_this.center(m_transition.end.center, null, needZoom, needZoom);
+          if (m_transition.end.center) {
+            var needZoom = m_zoom !== fix_zoom(m_transition.end.zoom);
+            m_this.center(m_transition.end.center, null, needZoom, needZoom);
+          }
           m_this.zoom(m_transition.end.zoom, m_transition.zoomOrigin);
           m_this.rotation(fix_rotation(m_transition.end.rotation));
         }