2d.transformation.rotate.wrap.html (1277B)
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.transformation.rotate.wrap</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.transformation.rotate.wrap</h1> 10 <p class="desc">rotate() wraps large positive values correctly</p> 11 12 13 <script> 14 var t = async_test("rotate() wraps large positive values correctly"); 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 = '#f00'; 25 ctx.fillRect(0, 0, 100, 50); 26 27 ctx.rotate(Math.PI * (1 + 4096)); // == pi (mod 2*pi) 28 // We need about pi +/- 0.001 in order to get correct-looking results 29 // 32-bit floats can store pi*4097 with precision 2^-10, so that should 30 // be safe enough on reasonable implementations 31 ctx.fillStyle = '#0f0'; 32 ctx.fillRect(-100, -50, 100, 50); 33 _assertPixel(canvas, 50,25, 0,255,0,255); 34 _assertPixel(canvas, 98,2, 0,255,0,255); 35 _assertPixel(canvas, 98,47, 0,255,0,255); 36 t.done(); 37 38 }); 39 </script>