<!DOCTYPE html>
<html>
  <head>
    <title>
      Test AudioParam.linearRampToValueAtTime
    </title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/webaudio/resources/audit-util.js"></script>
    <script src="/webaudio/resources/audit.js"></script>
    <script src="/webaudio/resources/audioparam-testing.js"></script>
  </head>
  <body>
    <script id="layout-test-code">
      let audit = Audit.createTaskRunner();

      // Play a long DC signal out through an AudioGainNode, and call
      // setValueAtTime() and linearRampToValueAtTime() at regular intervals to
      // set the starting and ending values for a linear ramp. Each time
      // interval has a ramp with a different starting and ending value so that
      // there is a discontinuity at each time interval boundary.  The
      // discontinuity is for testing timing.  Also, we alternate between an
      // increasing and decreasing ramp for each interval.

      // Number of tests to run.
      let numberOfTests = 100;

      // Max allowed difference between the rendered data and the expected
      // result.
      let maxAllowedError = 1.865e-6;

      // Set the gain node value to the specified value at the specified time.
      function setValue(value, time) {
        gainNode.gain.setValueAtTime(value, time);
      }

      // Generate a linear ramp ending at time |endTime| with an ending value of
      // |value|.
      function generateRamp(value, startTime, endTime){
          // |startTime| is ignored because the linear ramp uses the value from
          // the
          // setValueAtTime() call above.
          gainNode.gain.linearRampToValueAtTime(value, endTime)}

      audit.define(
          {
            label: 'test',
            description: 'AudioParam linearRampToValueAtTime() functionality'
          },
          function(task, should) {
            createAudioGraphAndTest(
                task, should, numberOfTests, 1, setValue, generateRamp,
                'linearRampToValueAtTime()', maxAllowedError,
                createLinearRampArray);
          });

      audit.run();
    </script>
  </body>
</html>
