commit 5e6c0f3195b302c96bdd670613c0460722913268
author Ytai Ben-Tsvi <ytai@google.com> Wed Jan 19 08:20:39 2022 -0800
committer Ytai Ben-Tsvi <ytai@google.com> Wed Jan 19 16:54:08 2022 -0800
tree bb1862345349fa1a93d1c321751940842e3789a1
parent dd31ee05cf3548819fabf6c82fda1abd15a2e137

Feed stillness detectors with pre-compensated poses

The drift compensator may create motion (toward center) that doesn't
actually exist physically, thus interfering with our ability to
determine stillness.

Test: Manual verification.
Change-Id: Id645c535328f909d8a490352df06e2000a9ad44e

media/libheadtracking/HeadTrackingProcessor.cpp

diff --git a/media/libheadtracking/HeadTrackingProcessor.cpp b/media/libheadtracking/HeadTrackingProcessor.cpp
index b2d2dbd..f2f15df 100644
--- a/media/libheadtracking/HeadTrackingProcessor.cpp
+++ b/media/libheadtracking/HeadTrackingProcessor.cpp
@@ -66,6 +66,7 @@
         Pose3f predictedWorldToHead =
                 worldToHead * integrate(headTwist, mOptions.predictionDuration);
         mHeadPoseDriftCompensator.setInput(timestamp, predictedWorldToHead);
+        mHeadStillnessDetector.setInput(timestamp, predictedWorldToHead);
         mWorldToHeadTimestamp = timestamp;
     }
 
@@ -76,8 +77,9 @@
             mPhysicalToLogicalAngle = mPendingPhysicalToLogicalAngle;
         }
 
-        mScreenPoseDriftCompensator.setInput(
-                timestamp, worldToScreen * Pose3f(rotateY(-mPhysicalToLogicalAngle)));
+        Pose3f worldToLogicalScreen = worldToScreen * Pose3f(rotateY(-mPhysicalToLogicalAngle));
+        mScreenPoseDriftCompensator.setInput(timestamp, worldToLogicalScreen);
+        mScreenStillnessDetector.setInput(timestamp, worldToLogicalScreen);
         mWorldToScreenTimestamp = timestamp;
     }
 
@@ -93,8 +95,6 @@
         // Handle the screen first, since it might trigger a recentering of the head.
         if (mWorldToScreenTimestamp.has_value()) {
             const Pose3f worldToLogicalScreen = mScreenPoseDriftCompensator.getOutput();
-            mScreenStillnessDetector.setInput(mWorldToScreenTimestamp.value(),
-                                              worldToLogicalScreen);
             bool screenStable = mScreenStillnessDetector.calculate(timestamp);
             mModeSelector.setScreenStable(mWorldToScreenTimestamp.value(), screenStable);
             // Whenever the screen is unstable, recenter the head pose.
@@ -108,7 +108,6 @@
         // Handle head.
         if (mWorldToHeadTimestamp.has_value()) {
             Pose3f worldToHead = mHeadPoseDriftCompensator.getOutput();
-            mHeadStillnessDetector.setInput(mWorldToHeadTimestamp.value(), worldToHead);
             // Auto-recenter.
             if (mHeadStillnessDetector.calculate(timestamp)) {
                 recenter(true, false);