Improve touch event resampling.

Fixed a few bugs related to the id-to-index mapping for
pointer coordinates.

Tightened the bounds on the resampling time interval to
avoid predicting too far into the future.

Only lerp X and Y components of motion events.

Alter the future to satisfy past predictions.  (Rewrite touch
events to conceal obvious discontinuities.)

Added a system property to control whether resampling is enabled
for debugging purposes.

Bug: 6375101
Change-Id: I35972d63278bc4e78148053a4125ad9abeebfedb

1 files changed, 0 insertions, 20 deletions

diff --git a/libs/androidfw/Input.cpp b/libs/androidfw/Input.cpp
index 40a6c47d031f..97b0ec127b59 100644
--- a/libs/androidfw/Input.cpp
+++ b/libs/androidfw/Input.cpp
@@ -211,26 +211,6 @@ void PointerCoords::scale(float scaleFactor) {
     scaleAxisValue(*this, AMOTION_EVENT_AXIS_TOOL_MINOR, scaleFactor);
 }
 
-void PointerCoords::lerp(const PointerCoords& a, const PointerCoords& b, float alpha) {
-    bits = 0;
-    for (uint64_t bitsRemaining = a.bits | b.bits; bitsRemaining; ) {
-        int32_t axis = __builtin_ctz(bitsRemaining);
-        uint64_t axisBit = 1LL << axis;
-        bitsRemaining &= ~axisBit;
-        if (a.bits & axisBit) {
-            if (b.bits & axisBit) {
-                float aval = a.getAxisValue(axis);
-                float bval = b.getAxisValue(axis);
-                setAxisValue(axis, aval + alpha * (bval - aval));
-            } else {
-                setAxisValue(axis, a.getAxisValue(axis));
-            }
-        } else {
-            setAxisValue(axis, b.getAxisValue(axis));
-        }
-    }
-}
-
 #ifdef HAVE_ANDROID_OS
 status_t PointerCoords::readFromParcel(Parcel* parcel) {
     bits = parcel->readInt64();