From 992870e2d24ea297ff658ee9cd6f39d4a71d9c0e Mon Sep 17 00:00:00 2001
From: Bart van den Eijnden <bartvde@boundlessgeo.com>
Date: Wed, 9 Dec 2015 15:27:20 +0100
Subject: [PATCH] Allow specifying non default DPI on ol.source.TileArcGISRest

---
 src/ol/source/tilearcgisrestsource.js            |  4 +++-
 test/spec/ol/source/tilearcgisrestsource.test.js | 10 ++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/ol/source/tilearcgisrestsource.js b/src/ol/source/tilearcgisrestsource.js
index 47ec86fd0f..1f05c3812d 100644
--- a/src/ol/source/tilearcgisrestsource.js
+++ b/src/ol/source/tilearcgisrestsource.js
@@ -102,7 +102,9 @@ ol.source.TileArcGISRest.prototype.getRequestUrl_ =
   params['BBOX'] = tileExtent.join(',');
   params['BBOXSR'] = srid;
   params['IMAGESR'] = srid;
-  params['DPI'] = Math.round(90 * pixelRatio);
+  params['DPI'] = Math.round(
+      params['DPI'] ? params['DPI'] * pixelRatio : 90 * pixelRatio
+      );
 
   var url;
   if (urls.length == 1) {
diff --git a/test/spec/ol/source/tilearcgisrestsource.test.js b/test/spec/ol/source/tilearcgisrestsource.test.js
index dc234b1df2..f0277f6f15 100644
--- a/test/spec/ol/source/tilearcgisrestsource.test.js
+++ b/test/spec/ol/source/tilearcgisrestsource.test.js
@@ -43,6 +43,16 @@ describe('ol.source.TileArcGISRest', function() {
       expect(queryData.get('DPI')).to.be('101');
     });
 
+    it('takes DPI from params if specified', function() {
+      options.params.DPI = 96;
+      var source = new ol.source.TileArcGISRest(options);
+      var tile = source.getTile(3, 2, -7, 1.12, ol.proj.get('EPSG:3857'));
+      var uri = new goog.Uri(tile.src_);
+      var queryData = uri.getQueryData();
+      expect(queryData.get('DPI')).to.be('108');
+      delete options.params.DPI;
+    });
+
     it('returns a tile with the expected URL with url list', function() {
 
       options.urls = ['http://test1.com/MapServer',