From 14e20e23a00adb9533a36ecece15806ed0d4b294 Mon Sep 17 00:00:00 2001
From: Petr Sloup <slouppetr@gmail.com>
Date: Tue, 25 Aug 2015 17:35:07 +0200
Subject: [PATCH] Correctly reproject projections with undefined units

---
 src/ol/reproj/image.js  | 13 ++++---------
 src/ol/reproj/reproj.js |  8 ++++++--
 src/ol/reproj/tile.js   | 38 +++++++++++++++++---------------------
 3 files changed, 27 insertions(+), 32 deletions(-)

diff --git a/src/ol/reproj/image.js b/src/ol/reproj/image.js
index 6841372bbe..af9e266afd 100644
--- a/src/ol/reproj/image.js
+++ b/src/ol/reproj/image.js
@@ -36,20 +36,19 @@ ol.reproj.Image = function(sourceProj, targetProj,
   var limitedTargetExtent = ol.extent.getIntersection(
       targetExtent, maxTargetExtent);
 
+  var targetCenter = ol.extent.getCenter(limitedTargetExtent);
+  var sourceResolution = ol.reproj.calculateSourceResolution(
+      sourceProj, targetProj, targetCenter, targetResolution);
 
   var errorThresholdInPixels = ol.DEFAULT_RASTER_REPROJ_ERROR_THRESHOLD;
 
-  // in source units
-  var errorThreshold = targetResolution * errorThresholdInPixels *
-      targetProj.getMetersPerUnit() / sourceProj.getMetersPerUnit();
-
   /**
    * @private
    * @type {!ol.reproj.Triangulation}
    */
   this.triangulation_ = new ol.reproj.Triangulation(
       sourceProj, targetProj, limitedTargetExtent, this.maxSourceExtent_,
-      errorThreshold);
+      sourceResolution * errorThresholdInPixels);
 
   /**
    * @private
@@ -65,10 +64,6 @@ ol.reproj.Image = function(sourceProj, targetProj,
 
   var srcExtent = this.triangulation_.calculateSourceExtent();
 
-  var targetCenter = ol.extent.getCenter(targetExtent);
-  var sourceResolution = ol.reproj.calculateSourceResolution(
-      sourceProj, targetProj, targetCenter, targetResolution);
-
   /**
    * @private
    * @type {ol.ImageBase}
diff --git a/src/ol/reproj/reproj.js b/src/ol/reproj/reproj.js
index 6dc5e90325..db42c15f68 100644
--- a/src/ol/reproj/reproj.js
+++ b/src/ol/reproj/reproj.js
@@ -27,10 +27,14 @@ ol.reproj.calculateSourceResolution = function(sourceProj, targetProj,
 
   var sourceCenter = ol.proj.transform(targetCenter, targetProj, sourceProj);
 
+  var targetMPU = targetProj.getMetersPerUnit();
+  var sourceMPU = sourceProj.getMetersPerUnit();
+
   // calculate the ideal resolution of the source data
   var sourceResolution =
-      targetProj.getPointResolution(targetResolution, targetCenter) *
-      targetProj.getMetersPerUnit() / sourceProj.getMetersPerUnit();
+      targetProj.getPointResolution(targetResolution, targetCenter);
+  if (goog.isDef(targetMPU)) sourceResolution *= targetMPU;
+  if (goog.isDef(sourceMPU)) sourceResolution /= sourceMPU;
 
   // based on the projection properties, the point resolution at the specified
   // coordinates may be slightly different. We need to reverse-compensate this
diff --git a/src/ol/reproj/tile.js b/src/ol/reproj/tile.js
index a6472e30f6..17ed887718 100644
--- a/src/ol/reproj/tile.js
+++ b/src/ol/reproj/tile.js
@@ -117,27 +117,6 @@ ol.reproj.Tile = function(sourceProj, sourceTileGrid,
 
   var targetResolution = targetTileGrid.getResolution(z);
 
-  var errorThresholdInPixels = goog.isDef(opt_errorThreshold) ?
-      opt_errorThreshold : ol.DEFAULT_RASTER_REPROJ_ERROR_THRESHOLD;
-
-  // in source units
-  var errorThreshold = targetResolution * errorThresholdInPixels *
-      targetProj.getMetersPerUnit() / sourceProj.getMetersPerUnit();
-
-  /**
-   * @private
-   * @type {!ol.reproj.Triangulation}
-   */
-  this.triangulation_ = new ol.reproj.Triangulation(
-      sourceProj, targetProj, limitedTargetExtent, maxSourceExtent,
-      errorThreshold);
-
-  if (this.triangulation_.getTriangles().length === 0) {
-    // no valid triangles -> EMPTY
-    this.state = ol.TileState.EMPTY;
-    return;
-  }
-
   var targetCenter = ol.extent.getCenter(limitedTargetExtent);
   var sourceResolution = ol.reproj.calculateSourceResolution(
       sourceProj, targetProj, targetCenter, targetResolution);
@@ -149,6 +128,23 @@ ol.reproj.Tile = function(sourceProj, sourceTileGrid,
     return;
   }
 
+  var errorThresholdInPixels = goog.isDef(opt_errorThreshold) ?
+      opt_errorThreshold : ol.DEFAULT_RASTER_REPROJ_ERROR_THRESHOLD;
+
+  /**
+   * @private
+   * @type {!ol.reproj.Triangulation}
+   */
+  this.triangulation_ = new ol.reproj.Triangulation(
+      sourceProj, targetProj, limitedTargetExtent, maxSourceExtent,
+      sourceResolution * errorThresholdInPixels);
+
+  if (this.triangulation_.getTriangles().length === 0) {
+    // no valid triangles -> EMPTY
+    this.state = ol.TileState.EMPTY;
+    return;
+  }
+
   this.srcZ_ = sourceTileGrid.getZForResolution(sourceResolution);
   var srcExtent = this.triangulation_.calculateSourceExtent();