From 6b13640eeb3cd16f1ae7529a5c719ded3a3e820e Mon Sep 17 00:00:00 2001
From: andrewlewis <andrewlewis@google.com>
Date: Mon, 28 Sep 2020 15:15:26 +0100
Subject: [PATCH] Fix position ramping behavior with AudioTrack speed params

Non-realtime AudioTrack playback speed was not taken into account when
extrapolating the old mode's position, causing the position not to
advance smoothly.

This should be a no-op when not using AudioTrack playback params for
speed adjustment.

Issue: #7982
PiperOrigin-RevId: 334151163
---
 RELEASENOTES.md                                              | 3 +++
 .../android/exoplayer2/audio/AudioTrackPositionTracker.java  | 5 ++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index 06dc79607e..f32120b675 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -22,6 +22,9 @@
         ([#7962](https://github.com/google/ExoPlayer/issues/7962)).
 *   Audio:
     *   Retry playback after some types of `AudioTrack` error.
+    *   Fix the default audio sink position not advancing correctly when using
+        `AudioTrack`-based speed adjustment
+        ([#7982](https://github.com/google/ExoPlayer/issues/7982)).
 *   Extractors:
     *   Add support for .mp2 boxes in the `AtomParsers`
         ([#7967](https://github.com/google/ExoPlayer/issues/7967)).
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/audio/AudioTrackPositionTracker.java b/library/core/src/main/java/com/google/android/exoplayer2/audio/AudioTrackPositionTracker.java
index 540ee098ee..8891a6d8d1 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/audio/AudioTrackPositionTracker.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/audio/AudioTrackPositionTracker.java
@@ -289,7 +289,10 @@ import java.lang.reflect.Method;
     if (elapsedSincePreviousModeUs < MODE_SWITCH_SMOOTHING_DURATION_US) {
       // Use a ramp to smooth between the old mode and the new one to avoid introducing a sudden
       // jump if the two modes disagree.
-      long previousModeProjectedPositionUs = previousModePositionUs + elapsedSincePreviousModeUs;
+      long previousModeProjectedPositionUs =
+          previousModePositionUs
+              + Util.getMediaDurationForPlayoutDuration(
+                  elapsedSincePreviousModeUs, audioTrackPlaybackSpeed);
       // A ramp consisting of 1000 points distributed over MODE_SWITCH_SMOOTHING_DURATION_US.
       long rampPoint = (elapsedSincePreviousModeUs * 1000) / MODE_SWITCH_SMOOTHING_DURATION_US;
       positionUs *= rampPoint;