Merge pull request #7341 from tschaub/raster-fix

Proper rendering of raster sources when there is a tile transition

test/rendering/ol/source/raster.test.js

@@ -0,0 +1,84 @@
+goog.require('ol.Map');
+goog.require('ol.View');
+goog.require('ol.layer.Image');
+goog.require('ol.source.Raster');
+goog.require('ol.source.XYZ');
+
+where('Uint8ClampedArray').describe('ol.rendering.source.Raster', function() {
+
+  function afterRender(source, raster, callback) {
+    var loading = 0;
+
+    source.on('tileloadstart', function(event) {
+      loading++;
+    });
+    source.on('tileloadend', function(event) {
+      loading--;
+      if (loading == 0) {
+        raster.once('afteroperations', function() {
+          callback();
+        });
+      }
+    });
+    source.on('tileloaderror', function(event) {
+      callback(new Error('Tile failed to load'));
+    });
+
+  }
+
+  var map;
+  function createMap(renderer, pixelRatio) {
+    map = new ol.Map({
+      target: createMapDiv(200, 200),
+      pixelRatio: pixelRatio,
+      renderer: renderer,
+      view: new ol.View({
+        center: [0, 0],
+        zoom: 0
+      })
+    });
+  }
+
+  afterEach(function() {
+    if (map) {
+      disposeMap(map);
+    }
+    map = null;
+  });
+
+  describe('raster source rendering', function() {
+    it('renders the result of an operation', function(done) {
+      createMap('canvas', 1);
+
+      var source = new ol.source.XYZ({
+        url: 'rendering/ol/data/tiles/osm/{z}/{x}/{y}.png',
+        transition: 0
+      });
+
+      var raster = new ol.source.Raster({
+        sources: [source],
+        operation: function(pixels) {
+          var pixel = pixels[0];
+          // swap blue and red
+          var red = pixel[0];
+          pixel[0] = pixel[2];
+          pixel[2] = red;
+          return pixel;
+        }
+      });
+
+      afterRender(source, raster, function(err) {
+        if (err) {
+          done(err);
+          return;
+        }
+        expectResemble(map, 'rendering/ol/source/expected/raster-1.png', IMAGE_TOLERANCE, done);
+      });
+
+      var layer = new ol.layer.Image({source: raster});
+
+      map.addLayer(layer);
+    });
+  });
+
+});