2d.imageData.create2.large.html (1371B)
1 <!DOCTYPE html> 2 <!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. --> 3 <meta charset="UTF-8"> 4 <title>OffscreenCanvas test: 2d.imageData.create2.large</title> 5 <script src="/resources/testharness.js"></script> 6 <script src="/resources/testharnessreport.js"></script> 7 <script src="/html/canvas/resources/canvas-tests.js"></script> 8 9 <h1>2d.imageData.create2.large</h1> 10 <p class="desc">createImageData(sw, sh) works for sizes much larger than the canvas</p> 11 12 13 <script> 14 var t = async_test("createImageData(sw, sh) works for sizes much larger than the canvas"); 15 var t_pass = t.done.bind(t); 16 var t_fail = t.step_func(function(reason) { 17 throw reason; 18 }); 19 t.step(function() { 20 21 var canvas = new OffscreenCanvas(100, 50); 22 var ctx = canvas.getContext('2d'); 23 24 var imgdata = ctx.createImageData(1000, 2000); 25 _assertSame(imgdata.data.length, imgdata.width*imgdata.height*4, "imgdata.data.length", "imgdata.width*imgdata.height*4"); 26 _assert(imgdata.width < imgdata.height, "imgdata.width < imgdata.height"); 27 _assert(imgdata.width > 0, "imgdata.width > 0"); 28 var isTransparentBlack = true; 29 for (var i = 0; i < imgdata.data.length; i += 7813) // check ~1024 points (assuming normal scaling) 30 if (imgdata.data[i] !== 0) 31 isTransparentBlack = false; 32 _assert(isTransparentBlack, "isTransparentBlack"); 33 t.done(); 34 35 }); 36 </script>