1 files changed, 54 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/canvas/offscreen/manual/filter/offscreencanvas.filter.w.html b/testing/web-platform/tests/html/canvas/offscreen/manual/filter/offscreencanvas.filter.w.html
new file mode 100644
index 0000000000..d6ed915b53
--- /dev/null
+++ b/testing/web-platform/tests/html/canvas/offscreen/manual/filter/offscreencanvas.filter.w.html
@@ -0,0 +1,54 @@
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="offscreencanvas.filter.js"></script>
+<script id='myWorker' type='text/worker'>
+self.onmessage = function(e) {
+  var getOffscreenCanvasForFilter = function(filter, pattern) {
+    var oc = new OffscreenCanvas(80, 80);
+    var offCtx = oc.getContext('2d');
+    offCtx.filter = filter;
+    offCtx.drawImage(pattern, 5, 5);
+    offCtx.drawImage(pattern, 25, 25);
+    offCtx.drawImage(pattern, 45, 45);
+    return oc;
+  };
+
+  var filters = e.data.filters;
+  var pattern = e.data.pattern;
+  var ret = [];
+  for (var i = 0; i < filters.length; i++) {
+     var oc = getOffscreenCanvasForFilter(filters[i], pattern);
+     var imageBitmap = oc.transferToImageBitmap();
+     ret.push(imageBitmap);
+  }
+  self.postMessage(ret, ret);
+};
+</script>
+<script>
+var patternCanvas = createPatternCanvas();
+
+// Build a list of image data on regular canvas with different filters
+var listCanvasImageData = [];
+for (var j = 0; j < filters.length; j++) {
+  var ctx = getRegularContextForFilter(filters[j], patternCanvas);
+  listCanvasImageData.push(ctx.getImageData(0, 0, 80, 80).data);
+}
+
+function consumeImageBitmap(patternImage) {
+  async_test(t => {
+    var blob = new Blob([document.getElementById('myWorker').textContent]);
+    var worker = new Worker(URL.createObjectURL(blob));
+    worker.addEventListener('message', msg => {
+      for (var i = 0; i < msg.data.length; ++i) {
+        var outputCtx = document.createElement("canvas").getContext('2d');
+        outputCtx.drawImage(msg.data[i], 0, 0, 80, 80);
+        matchImageDataResults(outputCtx.getImageData(0, 0, 80, 80).data, listCanvasImageData[i], filters[i]);
+      }
+      t.done();
+    });
+  worker.postMessage({filters: filters, pattern: patternImage}, [patternImage]);
+  });
+}
+
+createImageBitmap(patternCanvas).then(consumeImageBitmap);
+</script>