1 files changed, 117 insertions, 0 deletions
diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/context/context-attribute-preserve-drawing-buffer.html b/dom/canvas/test/webgl-conf/checkout/conformance/context/context-attribute-preserve-drawing-buffer.html
new file mode 100644
index 0000000000..7a023996fb
--- /dev/null
+++ b/dom/canvas/test/webgl-conf/checkout/conformance/context/context-attribute-preserve-drawing-buffer.html
@@ -0,0 +1,117 @@
+<!--
+Copyright (c) 2019 The Khronos Group Inc.
+Use of this source code is governed by an MIT-style license that can be
+found in the LICENSE.txt file.
+-->
+
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8">
+<link rel="stylesheet" href="../../resources/js-test-style.css"/>
+<script src="../../js/js-test-pre.js"></script>
+<script src="../../js/webgl-test-utils.js"></script>
+<style>
+.pattern {
+  white-space: nowrap;
+  display: inline-block;
+}
+canvas {
+  width:10px;
+  height:10px;
+}
+.square {
+  display:inline-block;
+  width:10px;
+  height:10px;
+  background-color:red;
+}
+</style>
+<script>
+"use strict";
+var wtu = WebGLTestUtils;
+function checkResult(ctx1, ctx2, preserve) {
+  var imgData1 = ctx1.getImageData(0,0,1,1);
+  var imgData2 = ctx2.getImageData(0,0,1,1);
+  var correct1 = [255,0,0,255];
+  var correct2 = preserve ? [255,0,0,255] : [0,0,0,255];
+  var ok1 = true;
+  var ok2 = true;
+  for (var p = 0; p < 4; ++p) {
+    if (imgData1.data[p] != correct1[p])
+      ok1 = false;
+    if (imgData2.data[p] != correct2[p])
+      ok2 = false;
+  }
+  if (ok1 && ok2)
+    testPassed('Rendered ok with preserveDrawingBuffer ' + preserve +'.');
+  else
+    testFailed('Did not render ok with preserveDrawingBuffer ' + preserve + '.');
+  if (preserve) {
+    finishTest()
+  } else {
+    runTest(true);
+  }
+}
+
+function runTest(preserve) {
+  var c1 = document.getElementById('c' + (preserve * 3 + 1));
+  var c2 = document.getElementById('c' + (preserve * 3 + 2));
+  var c3 = document.getElementById('c' + (preserve * 3 + 3));
+  var ctx1 = c1.getContext('2d');
+  var ctx2 = c2.getContext('2d');
+  var gl = wtu.create3DContext(c3, { alpha:false, preserveDrawingBuffer:preserve });
+  if (!gl) {
+    testFailed("context does not exist");
+    if (preserve) {
+      finishTest()
+    } else {
+      runTest(true);
+    }
+    return;
+  }
+  gl.clearColor(1, 0, 0, 1);
+  gl.clear(gl.COLOR_BUFFER_BIT);
+  ctx1.drawImage(c3, 0, 0);
+  wtu.waitForComposite(function() {
+    ctx2.drawImage(c3, 0, 0);
+    checkResult(ctx1, ctx2, preserve);
+  });
+}
+</script>
+</head>
+<body>
+<div class="pattern">
+  <canvas id='c1'></canvas>
+  <canvas id='c2'></canvas>
+  <canvas id='c3'></canvas>
+</div>
+<span>should look like</span>
+<div class="pattern">
+  <div class='square'></div>
+  <div class='square' style='background-color:black'></div>
+  <div class='square'></div>
+</div>
+<hr />
+<div class="pattern">
+  <canvas id='c4'></canvas>
+  <canvas id='c5'></canvas>
+  <canvas id='c6'></canvas>
+</div>
+<span>should look like</span>
+<div class="pattern">
+  <div class='square'></div>
+  <div class='square'></div>
+  <div class='square'></div>
+</div>
+<div id="description"></div>
+<div id="console"></div>
+<script>
+"use strict";
+description('Verify that preserveDrawingBuffer attribute is honored.');
+runTest(false);
+var successfullyParsed = true;
+shouldBeTrue("successfullyParsed");
+</script>
+</body>
+</html>