2d.composite.globalAlpha.canvas.html (1078B)
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.composite.globalAlpha.canvas</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.composite.globalAlpha.canvas</h1> 10 <p class="desc"></p> 11 12 13 <script> 14 var t = async_test(""); 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 offscreenCanvas2 = new OffscreenCanvas(100, 50); 25 var ctx2 = offscreenCanvas2.getContext('2d'); 26 ctx2.fillStyle = '#f00'; 27 ctx2.fillRect(0, 0, 100, 50); 28 ctx.fillStyle = '#0f0'; 29 ctx.fillRect(0, 0, 100, 50); 30 // Avoiding any potential alpha = 0 optimisations. 31 ctx.globalAlpha = 0.01; 32 ctx.drawImage(offscreenCanvas2, 0, 0); 33 _assertPixelApprox(canvas, 50,25, 2,253,0,255, 2); 34 t.done(); 35 36 }); 37 </script>