ADHOC/replicant-frameworks_native
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Revert velocity damping.

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Bug: 4364920

Velocity damping proved to be a bad idea because it would
cause a significant ramp in velocity at the beginning of
a gesture, instead of the desired smooth behavior.  Oh well.

Change-Id: Ie631946f47ef2492bd71fbed1ab44bbb39a875a8
This commit is contained in:
Jeff Brown 2011-06-06 20:23:54 -07:00
parent 2768505342
commit 7ca7ba2064
2 changed files with 0 additions and 14 deletions
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5
include/ui/Input.h
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@ -608,11 +608,6 @@ private:
// Oldest sample to consider when calculating the velocity.
static const nsecs_t MAX_AGE = 200 * 1000000; // 200 ms
// When the total duration of the window of samples being averaged is less
// than the window size, the resulting velocity is scaled to reduce the impact
// of overestimation in short traces.
static const nsecs_t MIN_WINDOW = 100 * 1000000; // 100 ms
// The minimum duration between samples when estimating velocity.
static const nsecs_t MIN_DURATION = 10 * 1000000; // 10 ms

9
libs/ui/Input.cpp
View File

@ -677,7 +677,6 @@ bool MotionEvent::isTouchEvent(int32_t source, int32_t action) {
const uint32_t VelocityTracker::HISTORY_SIZE;
const nsecs_t VelocityTracker::MAX_AGE;
const nsecs_t VelocityTracker::MIN_WINDOW;
const nsecs_t VelocityTracker::MIN_DURATION;
VelocityTracker::VelocityTracker() {
@ -868,14 +867,6 @@ bool VelocityTracker::getVelocity(uint32_t id, float* outVx, float* outVy) const
// Make sure we used at least one sample.
if (samplesUsed != 0) {
// Scale the velocity linearly if the window of samples is small.
nsecs_t totalDuration = newestMovement.eventTime - oldestMovement.eventTime;
if (totalDuration < MIN_WINDOW) {
float scale = float(totalDuration) / float(MIN_WINDOW);
accumVx *= scale;
accumVy *= scale;
}
*outVx = accumVx;
*outVy = accumVy;
return true;