2d.imageData.get.order.alpha.html (1033B)
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.get.order.alpha</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.get.order.alpha</h1> 10 <p class="desc">getImageData() returns A in the fourth component</p> 11 12 13 <script> 14 var t = async_test("getImageData() returns A in the fourth component"); 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 ctx.fillStyle = 'rgba(0, 0, 0, 0.5)'; 25 ctx.fillRect(0, 0, 100, 50); 26 var imgdata = ctx.getImageData(0, 0, 10, 10); 27 _assert(imgdata.data[3] < 200, "imgdata.data[\""+(3)+"\"] < 200"); 28 _assert(imgdata.data[3] > 100, "imgdata.data[\""+(3)+"\"] > 100"); 29 t.done(); 30 31 }); 32 </script>