Avoid rendering outside WebGL layer and source extent

test/rendering/cases/webgl-source-extent/main.js

@@ -0,0 +1,58 @@
+import Map from '../../../../src/ol/Map.js';
+import TileGrid from '../../../../src/ol/tilegrid/TileGrid.js';
+import TileLayer from '../../../../src/ol/layer/WebGLTile.js';
+import View from '../../../../src/ol/View.js';
+import XYZ from '../../../../src/ol/source/XYZ.js';
+import {getHeight, getWidth} from '../../../../src/ol/extent.js';
+import {get as getProjection} from '../../../../src/ol/proj.js';
+
+const fullExtent = getProjection('EPSG:3857').getExtent();
+const width = getWidth(fullExtent);
+const height = getHeight(fullExtent);
+
+const partialExtent = [
+  fullExtent[0],
+  fullExtent[1] + 0.4 * height,
+  fullExtent[2] - 0.4 * width,
+  fullExtent[3],
+];
+
+function resolutionsFromExtent(extent, maxZoom) {
+  const height = getHeight(extent);
+  const width = getWidth(extent);
+
+  const maxResolution = Math.max(width / 256, height / 256);
+
+  const length = maxZoom + 1;
+  const resolutions = new Array(length);
+  for (let z = 0; z < length; ++z) {
+    resolutions[z] = maxResolution / Math.pow(2, z);
+  }
+  return resolutions;
+}
+
+new Map({
+  layers: [
+    new TileLayer({
+      source: new XYZ({
+        wrapX: false,
+        url: '/data/tiles/satellite/{z}/{x}/{y}.jpg',
+        transition: 0,
+        tileGrid: new TileGrid({
+          extent: partialExtent,
+          resolutions: resolutionsFromExtent(fullExtent, 10),
+        }),
+      }),
+    }),
+  ],
+  target: 'map',
+  view: new View({
+    center: [0, 0],
+    zoom: 0,
+    rotation: -Math.PI / 8,
+  }),
+});
+
+render({
+  message: 'data outside the source tile grid extent is not rendered',
+});