tools/perf/perf_tools/smoothness_measurement.py

   1 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4 import os
   5
   6 class SmoothnessMeasurement(object):
   7   def __init__(self, tab):
   8     self._tab = tab
   9     # Bring in the smoothness benchmark
  10     with open(
  11       os.path.join(os.path.dirname(__file__),
  12                    'smoothness_measurement.js')) as f:
  13       js = f.read()
  14       tab.ExecuteJavaScript(js)
  15
  16   def Start(self):
  17     self._tab.ExecuteJavaScript(
  18         'window.__renderingStats = new __RenderingStats();'
  19         'window.__renderingStats.start()')
  20
  21   def Stop(self):
  22     self._tab.ExecuteJavaScript('window.__renderingStats.stop()')
  23
  24   def BindToAction(self, action):
  25     # Make the scroll test start and stop measurement automatically.
  26     self._tab.ExecuteJavaScript(
  27         'window.__renderingStats = new __RenderingStats();')
  28     action.BindMeasurementJavaScript(self._tab,
  29                                      'window.__renderingStats.start();',
  30                                      'window.__renderingStats.stop();')
  31
  32   @property
  33   def start_values(self):
  34     return self._tab.EvaluateJavaScript(
  35       'window.__renderingStats.getStartValues()')
  36
  37   @property
  38   def end_values(self):
  39     return self._tab.EvaluateJavaScript(
  40       'window.__renderingStats.getEndValues()')
  41
  42   @property
  43   def deltas(self):
  44     return self._tab.EvaluateJavaScript(
  45       'window.__renderingStats.getDeltas()')