| <!DOCTYPE html> |
| <meta name="viewport" content="width=device-width, user-scalable=no"> |
| <link rel="stylesheet" type="text/css" href="resources/tablet.css"> |
| <link rel="stylesheet" type="text/css" href="resources/transition.css"> |
| <script src="resources/perf_test_helper.js"></script> |
| |
| <container id="container"></container> |
| |
| <script> |
| var N = PerfTestHelper.getN(1000); |
| var duration = 1000; |
| var targets = []; |
| var styles = []; |
| var keyframeValues = [0, 1]; |
| |
| for (var i = 0; i < N; i++) { |
| var target = document.createElement('target'); |
| target._keyframe = 0; |
| container.appendChild(target); |
| targets.push(target); |
| } |
| |
| function addNewClassStyle(step) { |
| // Clean up overwritten styles. |
| var i = 0; |
| for (; i < styles.length && styles[i].lastStep < step; i++) { |
| styles[i].style.remove(); |
| } |
| styles.splice(0, i); |
| |
| var style = document.createElement('style'); |
| var className = 'style' + step + 'keyframe'; |
| style.textContent = '.' + className + '0 { opacity: ' + keyframeValues[0] + '; }\n'; |
| style.textContent += '.' + className + '1 { opacity: ' + keyframeValues[1] + '; }\n'; |
| container.appendChild(style); |
| styles.push({ |
| style: style, |
| lastStep: step + N, |
| }); |
| |
| return className; |
| } |
| |
| function startTransitions(startingTargets, startStep, endStep) { |
| var newClassName = addNewClassStyle(startStep, endStep); |
| startingTargets.forEach(function(startInfo) { |
| startInfo.target._keyframe ^= 1; |
| startInfo.target.className = newClassName + startInfo.target._keyframe; |
| startInfo.target.style.transitionDelay = -startInfo.fastForward + 'ms'; |
| }); |
| } |
| |
| requestAnimationFrame(function(time) { |
| var startTime = time - duration; |
| var previousStep = 0; |
| |
| function staggeredStart(time) { |
| var elapsed = time - startTime; |
| var targetStep = Math.floor(N * elapsed / duration); |
| var restartingTargets = []; |
| for (var step = Math.max(targetStep - N, previousStep); step < targetStep; step++) { |
| var stepStartTime = step / N * duration; |
| restartingTargets.push({ |
| target: targets[step % N], |
| fastForward: elapsed - stepStartTime, |
| }); |
| } |
| startTransitions(restartingTargets, targetStep); |
| previousStep = targetStep; |
| requestAnimationFrame(staggeredStart); |
| } |
| staggeredStart(time); |
| }); |
| |
| PerfTestHelper.signalReady(); |
| </script> |
