diff options
| author | Andrew de los Reyes <adlr@google.com> | 2015-10-01 15:57:25 -0700 |
|---|---|---|
| committer | Andrew de los Reyes <adlr@google.com> | 2015-10-01 15:57:25 -0700 |
| commit | de18f6c32add6fb22065807a00ddc88b363df527 (patch) | |
| tree | a0f877958b8be34fe0ac5d0e3329f5a898d2c83c | |
| parent | b0127aadafbf3b314475e48772fdcc17939c5a9c (diff) | |
| download | native-marshmallow-dr-dev.tar.gz | |
InputResampling: Don't extrapolate for very low frame rates.marshmallow-dr-dev
In very low framerate situations, extrapolation is generally going to
either cause no benefit or make a mistake. We can safely turn it off
with no user-visible negative impact.
BUG=https://buganizer.corp.google.com/u/0/issues/24550942
TEST=Scrolled very slowly and saw mispredictions on Angler. With change,
saw the log message that the mispredictions were suppressed.
Change-Id: Ic9747d3ff098d7918047ada2ed1c2d21282c65b0
| -rw-r--r-- | libs/input/InputTransport.cpp | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/libs/input/InputTransport.cpp b/libs/input/InputTransport.cpp index 0382f5788f..7f83da523f 100644 --- a/libs/input/InputTransport.cpp +++ b/libs/input/InputTransport.cpp @@ -51,6 +51,10 @@ static const nsecs_t RESAMPLE_LATENCY = 5 * NANOS_PER_MS; // Minimum time difference between consecutive samples before attempting to resample. static const nsecs_t RESAMPLE_MIN_DELTA = 2 * NANOS_PER_MS; +// Maximum time difference between consecutive samples before attempting to resample +// by extrapolation. +static const nsecs_t RESAMPLE_MAX_DELTA = 20 * NANOS_PER_MS; + // Maximum time to predict forward from the last known state, to avoid predicting too // far into the future. This time is further bounded by 50% of the last time delta. static const nsecs_t RESAMPLE_MAX_PREDICTION = 8 * NANOS_PER_MS; @@ -724,7 +728,7 @@ void InputConsumer::resampleTouchState(nsecs_t sampleTime, MotionEvent* event, nsecs_t delta = future.eventTime - current->eventTime; if (delta < RESAMPLE_MIN_DELTA) { #if DEBUG_RESAMPLING - ALOGD("Not resampled, delta time is %lld ns.", delta); + ALOGD("Not resampled, delta time is too small: %lld ns.", delta); #endif return; } @@ -736,7 +740,12 @@ void InputConsumer::resampleTouchState(nsecs_t sampleTime, MotionEvent* event, nsecs_t delta = current->eventTime - other->eventTime; if (delta < RESAMPLE_MIN_DELTA) { #if DEBUG_RESAMPLING - ALOGD("Not resampled, delta time is %lld ns.", delta); + ALOGD("Not resampled, delta time is too small: %lld ns.", delta); +#endif + return; + } else if (delta > RESAMPLE_MAX_DELTA) { +#if DEBUG_RESAMPLING + ALOGD("Not resampled, delta time is too large: %lld ns.", delta); #endif return; } |