Merge pull request #6002 from ahocevar/gutter-pixel-ratio

Use tile pixel ratio for gutter calculation

src/ol/renderer/canvas/tilelayer.js

@@ -232,7 +232,7 @@ ol.renderer.canvas.TileLayer.prototype.renderTileImages = function(context, fram
   var pixelScale = pixelRatio / resolution;
   var layer = this.getLayer();
   var source = /** @type {ol.source.Tile} */ (layer.getSource());
-  var tileGutter = pixelRatio * source.getGutter(projection);
+  var tileGutter = source.getTilePixelRatio(pixelRatio) * source.getGutter(projection);
   var tileGrid = source.getTileGridForProjection(projection);
 
   var hasRenderListeners = layer.hasListener(ol.render.Event.Type.RENDER);

src/ol/renderer/webgl/tilelayer.js

@@ -161,7 +161,7 @@ ol.renderer.webgl.TileLayer.prototype.prepareFrame = function(frameState, layerS
   var pixelRatio = tilePixelSize[0] /
       ol.size.toSize(tileGrid.getTileSize(z), this.tmpSize_)[0];
   var tilePixelResolution = tileResolution / pixelRatio;
-  var tileGutter = frameState.pixelRatio * tileSource.getGutter(projection);
+  var tileGutter = tileSource.getTilePixelRatio(pixelRatio) * tileSource.getGutter(projection);
 
   var center = viewState.center;
   var extent = frameState.extent;