More VelocityTracker refactoring.
Bug: 6413587
Change-Id: Ida1152e7a34d5fe5caab5e6b5e1bc79f6c7a25e6
diff --git a/libs/androidfw/VelocityTracker.cpp b/libs/androidfw/VelocityTracker.cpp
index 2fb094e..de214f8f 100644
--- a/libs/androidfw/VelocityTracker.cpp
+++ b/libs/androidfw/VelocityTracker.cpp
@@ -33,13 +33,7 @@
namespace android {
-// --- VelocityTracker ---
-
-const uint32_t VelocityTracker::DEFAULT_DEGREE;
-const nsecs_t VelocityTracker::DEFAULT_HORIZON;
-const uint32_t VelocityTracker::HISTORY_SIZE;
-
-static inline float vectorDot(const float* a, const float* b, uint32_t m) {
+static float vectorDot(const float* a, const float* b, uint32_t m) {
float r = 0;
while (m--) {
r += *(a++) * *(b++);
@@ -47,7 +41,7 @@
return r;
}
-static inline float vectorNorm(const float* a, uint32_t m) {
+static float vectorNorm(const float* a, uint32_t m) {
float r = 0;
while (m--) {
float t = *(a++);
@@ -91,45 +85,52 @@
}
#endif
-VelocityTracker::VelocityTracker() {
- clear();
+
+// --- VelocityTracker ---
+
+VelocityTracker::VelocityTracker() :
+ mCurrentPointerIdBits(0), mActivePointerId(-1),
+ mStrategy(new LeastSquaresVelocityTrackerStrategy()) {
+}
+
+VelocityTracker::VelocityTracker(VelocityTrackerStrategy* strategy) :
+ mCurrentPointerIdBits(0), mActivePointerId(-1),
+ mStrategy(strategy) {
+}
+
+VelocityTracker::~VelocityTracker() {
+ delete mStrategy;
}
void VelocityTracker::clear() {
- mIndex = 0;
- mMovements[0].idBits.clear();
+ mCurrentPointerIdBits.clear();
mActivePointerId = -1;
+
+ mStrategy->clear();
}
void VelocityTracker::clearPointers(BitSet32 idBits) {
- BitSet32 remainingIdBits(mMovements[mIndex].idBits.value & ~idBits.value);
- mMovements[mIndex].idBits = remainingIdBits;
+ BitSet32 remainingIdBits(mCurrentPointerIdBits.value & ~idBits.value);
+ mCurrentPointerIdBits = remainingIdBits;
if (mActivePointerId >= 0 && idBits.hasBit(mActivePointerId)) {
mActivePointerId = !remainingIdBits.isEmpty() ? remainingIdBits.firstMarkedBit() : -1;
}
+
+ mStrategy->clearPointers(idBits);
}
void VelocityTracker::addMovement(nsecs_t eventTime, BitSet32 idBits, const Position* positions) {
- if (++mIndex == HISTORY_SIZE) {
- mIndex = 0;
- }
-
while (idBits.count() > MAX_POINTERS) {
idBits.clearLastMarkedBit();
}
- Movement& movement = mMovements[mIndex];
- movement.eventTime = eventTime;
- movement.idBits = idBits;
- uint32_t count = idBits.count();
- for (uint32_t i = 0; i < count; i++) {
- movement.positions[i] = positions[i];
+ mCurrentPointerIdBits = idBits;
+ if (mActivePointerId < 0 || !idBits.hasBit(mActivePointerId)) {
+ mActivePointerId = idBits.isEmpty() ? -1 : idBits.firstMarkedBit();
}
- if (mActivePointerId < 0 || !idBits.hasBit(mActivePointerId)) {
- mActivePointerId = count != 0 ? idBits.firstMarkedBit() : -1;
- }
+ mStrategy->addMovement(eventTime, idBits, positions);
#if DEBUG_VELOCITY
ALOGD("VelocityTracker: addMovement eventTime=%lld, idBits=0x%08x, activePointerId=%d",
@@ -139,7 +140,7 @@
uint32_t index = idBits.getIndexOfBit(id);
iterBits.clearBit(id);
Estimator estimator;
- getEstimator(id, DEFAULT_DEGREE, DEFAULT_HORIZON, &estimator);
+ getEstimator(id, &estimator);
ALOGD(" %d: position (%0.3f, %0.3f), "
"estimator (degree=%d, xCoeff=%s, yCoeff=%s, confidence=%f)",
id, positions[index].x, positions[index].y,
@@ -215,6 +216,61 @@
addMovement(eventTime, idBits, positions);
}
+bool VelocityTracker::getVelocity(uint32_t id, float* outVx, float* outVy) const {
+ Estimator estimator;
+ if (getEstimator(id, &estimator) && estimator.degree >= 1) {
+ *outVx = estimator.xCoeff[1];
+ *outVy = estimator.yCoeff[1];
+ return true;
+ }
+ *outVx = 0;
+ *outVy = 0;
+ return false;
+}
+
+bool VelocityTracker::getEstimator(uint32_t id, Estimator* outEstimator) const {
+ return mStrategy->getEstimator(id, outEstimator);
+}
+
+
+// --- LeastSquaresVelocityTrackerStrategy ---
+
+const uint32_t LeastSquaresVelocityTrackerStrategy::DEGREE;
+const nsecs_t LeastSquaresVelocityTrackerStrategy::HORIZON;
+const uint32_t LeastSquaresVelocityTrackerStrategy::HISTORY_SIZE;
+
+LeastSquaresVelocityTrackerStrategy::LeastSquaresVelocityTrackerStrategy() {
+ clear();
+}
+
+LeastSquaresVelocityTrackerStrategy::~LeastSquaresVelocityTrackerStrategy() {
+}
+
+void LeastSquaresVelocityTrackerStrategy::clear() {
+ mIndex = 0;
+ mMovements[0].idBits.clear();
+}
+
+void LeastSquaresVelocityTrackerStrategy::clearPointers(BitSet32 idBits) {
+ BitSet32 remainingIdBits(mMovements[mIndex].idBits.value & ~idBits.value);
+ mMovements[mIndex].idBits = remainingIdBits;
+}
+
+void LeastSquaresVelocityTrackerStrategy::addMovement(nsecs_t eventTime, BitSet32 idBits,
+ const VelocityTracker::Position* positions) {
+ if (++mIndex == HISTORY_SIZE) {
+ mIndex = 0;
+ }
+
+ Movement& movement = mMovements[mIndex];
+ movement.eventTime = eventTime;
+ movement.idBits = idBits;
+ uint32_t count = idBits.count();
+ for (uint32_t i = 0; i < count; i++) {
+ movement.positions[i] = positions[i];
+ }
+}
+
/**
* Solves a linear least squares problem to obtain a N degree polynomial that fits
* the specified input data as nearly as possible.
@@ -361,22 +417,8 @@
return true;
}
-bool VelocityTracker::getVelocity(uint32_t id, float* outVx, float* outVy) const {
- Estimator estimator;
- if (getEstimator(id, DEFAULT_DEGREE, DEFAULT_HORIZON, &estimator)) {
- if (estimator.degree >= 1) {
- *outVx = estimator.xCoeff[1];
- *outVy = estimator.yCoeff[1];
- return true;
- }
- }
- *outVx = 0;
- *outVy = 0;
- return false;
-}
-
-bool VelocityTracker::getEstimator(uint32_t id, uint32_t degree, nsecs_t horizon,
- Estimator* outEstimator) const {
+bool LeastSquaresVelocityTrackerStrategy::getEstimator(uint32_t id,
+ VelocityTracker::Estimator* outEstimator) const {
outEstimator->clear();
// Iterate over movement samples in reverse time order and collect samples.
@@ -393,11 +435,11 @@
}
nsecs_t age = newestMovement.eventTime - movement.eventTime;
- if (age > horizon) {
+ if (age > HORIZON) {
break;
}
- const Position& position = movement.getPosition(id);
+ const VelocityTracker::Position& position = movement.getPosition(id);
x[m] = position.x;
y[m] = position.y;
time[m] = -age * 0.000000001f;
@@ -409,9 +451,7 @@
}
// Calculate a least squares polynomial fit.
- if (degree > Estimator::MAX_DEGREE) {
- degree = Estimator::MAX_DEGREE;
- }
+ uint32_t degree = DEGREE;
if (degree > m - 1) {
degree = m - 1;
}