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Merge "Minor refactoring before starting on velocity tracker changes." into jb-dev

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This commit is contained in:
Jeff Brown
2012-05-11 14:03:38 -07:00
committed by Android (Google) Code Review
parent ef27936371 8a90e6e317
commit b12b6b5116
11 changed files with 811 additions and 685 deletions
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18
core/java/android/view/VelocityTracker.java
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@@ -298,6 +298,24 @@ public final class VelocityTracker implements Poolable<VelocityTracker> {
return estimate(time, yCoeff);
}
/**
* Gets the X coefficient with the specified index.
* @param index The index of the coefficient to return.
* @return The X coefficient, or 0 if the index is greater than the degree.
*/
public float getXCoeff(int index) {
return index <= degree ? xCoeff[index] : 0;
}
/**
* Gets the Y coefficient with the specified index.
* @param index The index of the coefficient to return.
* @return The Y coefficient, or 0 if the index is greater than the degree.
*/
public float getYCoeff(int index) {
return index <= degree ? yCoeff[index] : 0;
}
private float estimate(float time, float[] c) {
float a = 0;
float scale = 1;

1
core/jni/android_view_VelocityTracker.cpp
View File

@@ -21,6 +21,7 @@
#include <android_runtime/AndroidRuntime.h>
#include <utils/Log.h>
#include <androidfw/Input.h>
#include <androidfw/VelocityTracker.h>
#include "android_view_MotionEvent.h"

177
include/androidfw/Input.h
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@@ -27,7 +27,6 @@
#include <utils/Timers.h>
#include <utils/RefBase.h>
#include <utils/String8.h>
#include <utils/BitSet.h>
#ifdef HAVE_ANDROID_OS
class SkMatrix;
@@ -607,182 +606,6 @@ private:
Vector<MotionEvent*> mMotionEventPool;
};
/*
* Calculates the velocity of pointer movements over time.
*/
class VelocityTracker {
public:
// Default polynomial degree. (used by getVelocity)
static const uint32_t DEFAULT_DEGREE = 2;
// Default sample horizon. (used by getVelocity)
// We don't use too much history by default since we want to react to quick
// changes in direction.
static const nsecs_t DEFAULT_HORIZON = 100 * 1000000; // 100 ms
struct Position {
float x, y;
};
struct Estimator {
static const size_t MAX_DEGREE = 2;
// Polynomial coefficients describing motion in X and Y.
float xCoeff[MAX_DEGREE + 1], yCoeff[MAX_DEGREE + 1];
// Polynomial degree (number of coefficients), or zero if no information is
// available.
uint32_t degree;
// Confidence (coefficient of determination), between 0 (no fit) and 1 (perfect fit).
float confidence;
inline void clear() {
degree = 0;
confidence = 0;
for (size_t i = 0; i <= MAX_DEGREE; i++) {
xCoeff[i] = 0;
yCoeff[i] = 0;
}
}
};
VelocityTracker();
// Resets the velocity tracker state.
void clear();
// Resets the velocity tracker state for specific pointers.
// Call this method when some pointers have changed and may be reusing
// an id that was assigned to a different pointer earlier.
void clearPointers(BitSet32 idBits);
// Adds movement information for a set of pointers.
// The idBits bitfield specifies the pointer ids of the pointers whose positions
// are included in the movement.
// The positions array contains position information for each pointer in order by
// increasing id. Its size should be equal to the number of one bits in idBits.
void addMovement(nsecs_t eventTime, BitSet32 idBits, const Position* positions);
// Adds movement information for all pointers in a MotionEvent, including historical samples.
void addMovement(const MotionEvent* event);
// Gets the velocity of the specified pointer id in position units per second.
// Returns false and sets the velocity components to zero if there is
// insufficient movement information for the pointer.
bool getVelocity(uint32_t id, float* outVx, float* outVy) const;
// Gets a quadratic estimator for the movements of the specified pointer id.
// Returns false and clears the estimator if there is no information available
// about the pointer.
bool getEstimator(uint32_t id, uint32_t degree, nsecs_t horizon,
Estimator* outEstimator) const;
// Gets the active pointer id, or -1 if none.
inline int32_t getActivePointerId() const { return mActivePointerId; }
// Gets a bitset containing all pointer ids from the most recent movement.
inline BitSet32 getCurrentPointerIdBits() const { return mMovements[mIndex].idBits; }
private:
// Number of samples to keep.
static const uint32_t HISTORY_SIZE = 20;
struct Movement {
nsecs_t eventTime;
BitSet32 idBits;
Position positions[MAX_POINTERS];
inline const Position& getPosition(uint32_t id) const {
return positions[idBits.getIndexOfBit(id)];
}
};
uint32_t mIndex;
Movement mMovements[HISTORY_SIZE];
int32_t mActivePointerId;
};
/*
* Specifies parameters that govern pointer or wheel acceleration.
*/
struct VelocityControlParameters {
// A scale factor that is multiplied with the raw velocity deltas
// prior to applying any other velocity control factors. The scale
// factor should be used to adapt the input device resolution
// (eg. counts per inch) to the output device resolution (eg. pixels per inch).
//
// Must be a positive value.
// Default is 1.0 (no scaling).
float scale;
// The scaled speed at which acceleration begins to be applied.
// This value establishes the upper bound of a low speed regime for
// small precise motions that are performed without any acceleration.
//
// Must be a non-negative value.
// Default is 0.0 (no low threshold).
float lowThreshold;
// The scaled speed at which maximum acceleration is applied.
// The difference between highThreshold and lowThreshold controls
// the range of speeds over which the acceleration factor is interpolated.
// The wider the range, the smoother the acceleration.
//
// Must be a non-negative value greater than or equal to lowThreshold.
// Default is 0.0 (no high threshold).
float highThreshold;
// The acceleration factor.
// When the speed is above the low speed threshold, the velocity will scaled
// by an interpolated value between 1.0 and this amount.
//
// Must be a positive greater than or equal to 1.0.
// Default is 1.0 (no acceleration).
float acceleration;
VelocityControlParameters() :
scale(1.0f), lowThreshold(0.0f), highThreshold(0.0f), acceleration(1.0f) {
}
VelocityControlParameters(float scale, float lowThreshold,
float highThreshold, float acceleration) :
scale(scale), lowThreshold(lowThreshold),
highThreshold(highThreshold), acceleration(acceleration) {
}
};
/*
* Implements mouse pointer and wheel speed control and acceleration.
*/
class VelocityControl {
public:
VelocityControl();
/* Sets the various parameters. */
void setParameters(const VelocityControlParameters& parameters);
/* Resets the current movement counters to zero.
* This has the effect of nullifying any acceleration. */
void reset();
/* Translates a raw movement delta into an appropriately
* scaled / accelerated delta based on the current velocity. */
void move(nsecs_t eventTime, float* deltaX, float* deltaY);
private:
// If no movements are received within this amount of time,
// we assume the movement has stopped and reset the movement counters.
static const nsecs_t STOP_TIME = 500 * 1000000; // 500 ms
VelocityControlParameters mParameters;
nsecs_t mLastMovementTime;
VelocityTracker::Position mRawPosition;
VelocityTracker mVelocityTracker;
};
} // namespace android
#endif // _ANDROIDFW_INPUT_H

107
include/androidfw/VelocityControl.h Normal file
View File

@@ -0,0 +1,107 @@
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _ANDROIDFW_VELOCITY_CONTROL_H
#define _ANDROIDFW_VELOCITY_CONTROL_H
#include <androidfw/Input.h>
#include <androidfw/VelocityTracker.h>
#include <utils/Timers.h>
namespace android {
/*
* Specifies parameters that govern pointer or wheel acceleration.
*/
struct VelocityControlParameters {
// A scale factor that is multiplied with the raw velocity deltas
// prior to applying any other velocity control factors. The scale
// factor should be used to adapt the input device resolution
// (eg. counts per inch) to the output device resolution (eg. pixels per inch).
//
// Must be a positive value.
// Default is 1.0 (no scaling).
float scale;
// The scaled speed at which acceleration begins to be applied.
// This value establishes the upper bound of a low speed regime for
// small precise motions that are performed without any acceleration.
//
// Must be a non-negative value.
// Default is 0.0 (no low threshold).
float lowThreshold;
// The scaled speed at which maximum acceleration is applied.
// The difference between highThreshold and lowThreshold controls
// the range of speeds over which the acceleration factor is interpolated.
// The wider the range, the smoother the acceleration.
//
// Must be a non-negative value greater than or equal to lowThreshold.
// Default is 0.0 (no high threshold).
float highThreshold;
// The acceleration factor.
// When the speed is above the low speed threshold, the velocity will scaled
// by an interpolated value between 1.0 and this amount.
//
// Must be a positive greater than or equal to 1.0.
// Default is 1.0 (no acceleration).
float acceleration;
VelocityControlParameters() :
scale(1.0f), lowThreshold(0.0f), highThreshold(0.0f), acceleration(1.0f) {
}
VelocityControlParameters(float scale, float lowThreshold,
float highThreshold, float acceleration) :
scale(scale), lowThreshold(lowThreshold),
highThreshold(highThreshold), acceleration(acceleration) {
}
};
/*
* Implements mouse pointer and wheel speed control and acceleration.
*/
class VelocityControl {
public:
VelocityControl();
/* Sets the various parameters. */
void setParameters(const VelocityControlParameters& parameters);
/* Resets the current movement counters to zero.
* This has the effect of nullifying any acceleration. */
void reset();
/* Translates a raw movement delta into an appropriately
* scaled / accelerated delta based on the current velocity. */
void move(nsecs_t eventTime, float* deltaX, float* deltaY);
private:
// If no movements are received within this amount of time,
// we assume the movement has stopped and reset the movement counters.
static const nsecs_t STOP_TIME = 500 * 1000000; // 500 ms
VelocityControlParameters mParameters;
nsecs_t mLastMovementTime;
VelocityTracker::Position mRawPosition;
VelocityTracker mVelocityTracker;
};
} // namespace android
#endif // _ANDROIDFW_VELOCITY_CONTROL_H

124
include/androidfw/VelocityTracker.h Normal file
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@@ -0,0 +1,124 @@
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _ANDROIDFW_VELOCITY_TRACKER_H
#define _ANDROIDFW_VELOCITY_TRACKER_H
#include <androidfw/Input.h>
#include <utils/Timers.h>
#include <utils/BitSet.h>
namespace android {
/*
* Calculates the velocity of pointer movements over time.
*/
class VelocityTracker {
public:
// Default polynomial degree. (used by getVelocity)
static const uint32_t DEFAULT_DEGREE = 2;
// Default sample horizon. (used by getVelocity)
// We don't use too much history by default since we want to react to quick
// changes in direction.
static const nsecs_t DEFAULT_HORIZON = 100 * 1000000; // 100 ms
struct Position {
float x, y;
};
struct Estimator {
static const size_t MAX_DEGREE = 2;
// Polynomial coefficients describing motion in X and Y.
float xCoeff[MAX_DEGREE + 1], yCoeff[MAX_DEGREE + 1];
// Polynomial degree (number of coefficients), or zero if no information is
// available.
uint32_t degree;
// Confidence (coefficient of determination), between 0 (no fit) and 1 (perfect fit).
float confidence;
inline void clear() {
degree = 0;
confidence = 0;
for (size_t i = 0; i <= MAX_DEGREE; i++) {
xCoeff[i] = 0;
yCoeff[i] = 0;
}
}
};
VelocityTracker();
// Resets the velocity tracker state.
void clear();
// Resets the velocity tracker state for specific pointers.
// Call this method when some pointers have changed and may be reusing
// an id that was assigned to a different pointer earlier.
void clearPointers(BitSet32 idBits);
// Adds movement information for a set of pointers.
// The idBits bitfield specifies the pointer ids of the pointers whose positions
// are included in the movement.
// The positions array contains position information for each pointer in order by
// increasing id. Its size should be equal to the number of one bits in idBits.
void addMovement(nsecs_t eventTime, BitSet32 idBits, const Position* positions);
// Adds movement information for all pointers in a MotionEvent, including historical samples.
void addMovement(const MotionEvent* event);
// Gets the velocity of the specified pointer id in position units per second.
// Returns false and sets the velocity components to zero if there is
// insufficient movement information for the pointer.
bool getVelocity(uint32_t id, float* outVx, float* outVy) const;
// Gets a quadratic estimator for the movements of the specified pointer id.
// Returns false and clears the estimator if there is no information available
// about the pointer.
bool getEstimator(uint32_t id, uint32_t degree, nsecs_t horizon,
Estimator* outEstimator) const;
// Gets the active pointer id, or -1 if none.
inline int32_t getActivePointerId() const { return mActivePointerId; }
// Gets a bitset containing all pointer ids from the most recent movement.
inline BitSet32 getCurrentPointerIdBits() const { return mMovements[mIndex].idBits; }
private:
// Number of samples to keep.
static const uint32_t HISTORY_SIZE = 20;
struct Movement {
nsecs_t eventTime;
BitSet32 idBits;
Position positions[MAX_POINTERS];
inline const Position& getPosition(uint32_t id) const {
return positions[idBits.getIndexOfBit(id)];
}
};
uint32_t mIndex;
Movement mMovements[HISTORY_SIZE];
int32_t mActivePointerId;
};
} // namespace android
#endif // _ANDROIDFW_VELOCITY_TRACKER_H

2
libs/androidfw/Android.mk
View File

@@ -33,6 +33,8 @@ commonUiSources:= \
Keyboard.cpp \
KeyCharacterMap.cpp \
KeyLayoutMap.cpp \
VelocityControl.cpp \
VelocityTracker.cpp \
VirtualKeyMap.cpp
commonSources:= \

510
libs/androidfw/Input.cpp
View File

@@ -15,31 +15,13 @@
*/
#define LOG_TAG "Input"
//#define LOG_NDEBUG 0
// Log debug messages about keymap probing.
#define DEBUG_PROBE 0
// Log debug messages about velocity tracking.
#define DEBUG_VELOCITY 0
// Log debug messages about least squares fitting.
#define DEBUG_LEAST_SQUARES 0
// Log debug messages about acceleration.
#define DEBUG_ACCELERATION 0
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include <androidfw/Input.h>
#include <math.h>
#include <limits.h>
#include <androidfw/Input.h>
#ifdef HAVE_ANDROID_OS
#include <binder/Parcel.h>
@@ -665,492 +647,4 @@ void PooledInputEventFactory::recycle(InputEvent* event) {
delete event;
}
// --- 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) {
float r = 0;
while (m--) {
r += *(a++) * *(b++);
}
return r;
}
static inline float vectorNorm(const float* a, uint32_t m) {
float r = 0;
while (m--) {
float t = *(a++);
r += t * t;
}
return sqrtf(r);
}
#if DEBUG_LEAST_SQUARES || DEBUG_VELOCITY
static String8 vectorToString(const float* a, uint32_t m) {
String8 str;
str.append("[");
while (m--) {
str.appendFormat(" %f", *(a++));
if (m) {
str.append(",");
}
}
str.append(" ]");
return str;
}
static String8 matrixToString(const float* a, uint32_t m, uint32_t n, bool rowMajor) {
String8 str;
str.append("[");
for (size_t i = 0; i < m; i++) {
if (i) {
str.append(",");
}
str.append(" [");
for (size_t j = 0; j < n; j++) {
if (j) {
str.append(",");
}
str.appendFormat(" %f", a[rowMajor ? i * n + j : j * m + i]);
}
str.append(" ]");
}
str.append(" ]");
return str;
}
#endif
VelocityTracker::VelocityTracker() {
clear();
}
void VelocityTracker::clear() {
mIndex = 0;
mMovements[0].idBits.clear();
mActivePointerId = -1;
}
void VelocityTracker::clearPointers(BitSet32 idBits) {
BitSet32 remainingIdBits(mMovements[mIndex].idBits.value & ~idBits.value);
mMovements[mIndex].idBits = remainingIdBits;
if (mActivePointerId >= 0 && idBits.hasBit(mActivePointerId)) {
mActivePointerId = !remainingIdBits.isEmpty() ? remainingIdBits.firstMarkedBit() : -1;
}
}
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];
}
if (mActivePointerId < 0 || !idBits.hasBit(mActivePointerId)) {
mActivePointerId = count != 0 ? idBits.firstMarkedBit() : -1;
}
#if DEBUG_VELOCITY
ALOGD("VelocityTracker: addMovement eventTime=%lld, idBits=0x%08x, activePointerId=%d",
eventTime, idBits.value, mActivePointerId);
for (BitSet32 iterBits(idBits); !iterBits.isEmpty(); ) {
uint32_t id = iterBits.firstMarkedBit();
uint32_t index = idBits.getIndexOfBit(id);
iterBits.clearBit(id);
Estimator estimator;
getEstimator(id, DEFAULT_DEGREE, DEFAULT_HORIZON, &estimator);
ALOGD(" %d: position (%0.3f, %0.3f), "
"estimator (degree=%d, xCoeff=%s, yCoeff=%s, confidence=%f)",
id, positions[index].x, positions[index].y,
int(estimator.degree),
vectorToString(estimator.xCoeff, estimator.degree).string(),
vectorToString(estimator.yCoeff, estimator.degree).string(),
estimator.confidence);
}
#endif
}
void VelocityTracker::addMovement(const MotionEvent* event) {
int32_t actionMasked = event->getActionMasked();
switch (actionMasked) {
case AMOTION_EVENT_ACTION_DOWN:
case AMOTION_EVENT_ACTION_HOVER_ENTER:
// Clear all pointers on down before adding the new movement.
clear();
break;
case AMOTION_EVENT_ACTION_POINTER_DOWN: {
// Start a new movement trace for a pointer that just went down.
// We do this on down instead of on up because the client may want to query the
// final velocity for a pointer that just went up.
BitSet32 downIdBits;
downIdBits.markBit(event->getPointerId(event->getActionIndex()));
clearPointers(downIdBits);
break;
}
case AMOTION_EVENT_ACTION_MOVE:
case AMOTION_EVENT_ACTION_HOVER_MOVE:
break;
default:
// Ignore all other actions because they do not convey any new information about
// pointer movement. We also want to preserve the last known velocity of the pointers.
// Note that ACTION_UP and ACTION_POINTER_UP always report the last known position
// of the pointers that went up. ACTION_POINTER_UP does include the new position of
// pointers that remained down but we will also receive an ACTION_MOVE with this
// information if any of them actually moved. Since we don't know how many pointers
// will be going up at once it makes sense to just wait for the following ACTION_MOVE
// before adding the movement.
return;
}
size_t pointerCount = event->getPointerCount();
if (pointerCount > MAX_POINTERS) {
pointerCount = MAX_POINTERS;
}
BitSet32 idBits;
for (size_t i = 0; i < pointerCount; i++) {
idBits.markBit(event->getPointerId(i));
}
nsecs_t eventTime;
Position positions[pointerCount];
size_t historySize = event->getHistorySize();
for (size_t h = 0; h < historySize; h++) {
eventTime = event->getHistoricalEventTime(h);
for (size_t i = 0; i < pointerCount; i++) {
positions[i].x = event->getHistoricalX(i, h);
positions[i].y = event->getHistoricalY(i, h);
}
addMovement(eventTime, idBits, positions);
}
eventTime = event->getEventTime();
for (size_t i = 0; i < pointerCount; i++) {
positions[i].x = event->getX(i);
positions[i].y = event->getY(i);
}
addMovement(eventTime, idBits, positions);
}
/**
* Solves a linear least squares problem to obtain a N degree polynomial that fits
* the specified input data as nearly as possible.
*
* Returns true if a solution is found, false otherwise.
*
* The input consists of two vectors of data points X and Y with indices 0..m-1.
* The output is a vector B with indices 0..n-1 that describes a polynomial
* that fits the data, such the sum of abs(Y[i] - (B[0] + B[1] X[i] + B[2] X[i]^2 ... B[n] X[i]^n))
* for all i between 0 and m-1 is minimized.
*
* That is to say, the function that generated the input data can be approximated
* by y(x) ~= B[0] + B[1] x + B[2] x^2 + ... + B[n] x^n.
*
* The coefficient of determination (R^2) is also returned to describe the goodness
* of fit of the model for the given data. It is a value between 0 and 1, where 1
* indicates perfect correspondence.
*
* This function first expands the X vector to a m by n matrix A such that
* A[i][0] = 1, A[i][1] = X[i], A[i][2] = X[i]^2, ..., A[i][n] = X[i]^n.
*
* Then it calculates the QR decomposition of A yielding an m by m orthonormal matrix Q
* and an m by n upper triangular matrix R. Because R is upper triangular (lower
* part is all zeroes), we can simplify the decomposition into an m by n matrix
* Q1 and a n by n matrix R1 such that A = Q1 R1.
*
* Finally we solve the system of linear equations given by R1 B = (Qtranspose Y)
* to find B.
*
* For efficiency, we lay out A and Q column-wise in memory because we frequently
* operate on the column vectors. Conversely, we lay out R row-wise.
*
* http://en.wikipedia.org/wiki/Numerical_methods_for_linear_least_squares
* http://en.wikipedia.org/wiki/Gram-Schmidt
*/
static bool solveLeastSquares(const float* x, const float* y, uint32_t m, uint32_t n,
float* outB, float* outDet) {
#if DEBUG_LEAST_SQUARES
ALOGD("solveLeastSquares: m=%d, n=%d, x=%s, y=%s", int(m), int(n),
vectorToString(x, m).string(), vectorToString(y, m).string());
#endif
// Expand the X vector to a matrix A.
float a[n][m]; // column-major order
for (uint32_t h = 0; h < m; h++) {
a[0][h] = 1;
for (uint32_t i = 1; i < n; i++) {
a[i][h] = a[i - 1][h] * x[h];
}
}
#if DEBUG_LEAST_SQUARES
ALOGD(" - a=%s", matrixToString(&a[0][0], m, n, false /*rowMajor*/).string());
#endif
// Apply the Gram-Schmidt process to A to obtain its QR decomposition.
float q[n][m]; // orthonormal basis, column-major order
float r[n][n]; // upper triangular matrix, row-major order
for (uint32_t j = 0; j < n; j++) {
for (uint32_t h = 0; h < m; h++) {
q[j][h] = a[j][h];
}
for (uint32_t i = 0; i < j; i++) {
float dot = vectorDot(&q[j][0], &q[i][0], m);
for (uint32_t h = 0; h < m; h++) {
q[j][h] -= dot * q[i][h];
}
}
float norm = vectorNorm(&q[j][0], m);
if (norm < 0.000001f) {
// vectors are linearly dependent or zero so no solution
#if DEBUG_LEAST_SQUARES
ALOGD(" - no solution, norm=%f", norm);
#endif
return false;
}
float invNorm = 1.0f / norm;
for (uint32_t h = 0; h < m; h++) {
q[j][h] *= invNorm;
}
for (uint32_t i = 0; i < n; i++) {
r[j][i] = i < j ? 0 : vectorDot(&q[j][0], &a[i][0], m);
}
}
#if DEBUG_LEAST_SQUARES
ALOGD(" - q=%s", matrixToString(&q[0][0], m, n, false /*rowMajor*/).string());
ALOGD(" - r=%s", matrixToString(&r[0][0], n, n, true /*rowMajor*/).string());
// calculate QR, if we factored A correctly then QR should equal A
float qr[n][m];
for (uint32_t h = 0; h < m; h++) {
for (uint32_t i = 0; i < n; i++) {
qr[i][h] = 0;
for (uint32_t j = 0; j < n; j++) {
qr[i][h] += q[j][h] * r[j][i];
}
}
}
ALOGD(" - qr=%s", matrixToString(&qr[0][0], m, n, false /*rowMajor*/).string());
#endif
// Solve R B = Qt Y to find B. This is easy because R is upper triangular.
// We just work from bottom-right to top-left calculating B's coefficients.
for (uint32_t i = n; i-- != 0; ) {
outB[i] = vectorDot(&q[i][0], y, m);
for (uint32_t j = n - 1; j > i; j--) {
outB[i] -= r[i][j] * outB[j];
}
outB[i] /= r[i][i];
}
#if DEBUG_LEAST_SQUARES
ALOGD(" - b=%s", vectorToString(outB, n).string());
#endif
// Calculate the coefficient of determination as 1 - (SSerr / SStot) where
// SSerr is the residual sum of squares (squared variance of the error),
// and SStot is the total sum of squares (squared variance of the data).
float ymean = 0;
for (uint32_t h = 0; h < m; h++) {
ymean += y[h];
}
ymean /= m;
float sserr = 0;
float sstot = 0;
for (uint32_t h = 0; h < m; h++) {
float err = y[h] - outB[0];
float term = 1;
for (uint32_t i = 1; i < n; i++) {
term *= x[h];
err -= term * outB[i];
}
sserr += err * err;
float var = y[h] - ymean;
sstot += var * var;
}
*outDet = sstot > 0.000001f ? 1.0f - (sserr / sstot) : 1;
#if DEBUG_LEAST_SQUARES
ALOGD(" - sserr=%f", sserr);
ALOGD(" - sstot=%f", sstot);
ALOGD(" - det=%f", *outDet);
#endif
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 {
outEstimator->clear();
// Iterate over movement samples in reverse time order and collect samples.
float x[HISTORY_SIZE];
float y[HISTORY_SIZE];
float time[HISTORY_SIZE];
uint32_t m = 0;
uint32_t index = mIndex;
const Movement& newestMovement = mMovements[mIndex];
do {
const Movement& movement = mMovements[index];
if (!movement.idBits.hasBit(id)) {
break;
}
nsecs_t age = newestMovement.eventTime - movement.eventTime;
if (age > horizon) {
break;
}
const Position& position = movement.getPosition(id);
x[m] = position.x;
y[m] = position.y;
time[m] = -age * 0.000000001f;
index = (index == 0 ? HISTORY_SIZE : index) - 1;
} while (++m < HISTORY_SIZE);
if (m == 0) {
return false; // no data
}
// Calculate a least squares polynomial fit.
if (degree > Estimator::MAX_DEGREE) {
degree = Estimator::MAX_DEGREE;
}
if (degree > m - 1) {
degree = m - 1;
}
if (degree >= 1) {
float xdet, ydet;
uint32_t n = degree + 1;
if (solveLeastSquares(time, x, m, n, outEstimator->xCoeff, &xdet)
&& solveLeastSquares(time, y, m, n, outEstimator->yCoeff, &ydet)) {
outEstimator->degree = degree;
outEstimator->confidence = xdet * ydet;
#if DEBUG_LEAST_SQUARES
ALOGD("estimate: degree=%d, xCoeff=%s, yCoeff=%s, confidence=%f",
int(outEstimator->degree),
vectorToString(outEstimator->xCoeff, n).string(),
vectorToString(outEstimator->yCoeff, n).string(),
outEstimator->confidence);
#endif
return true;
}
}
// No velocity data available for this pointer, but we do have its current position.
outEstimator->xCoeff[0] = x[0];
outEstimator->yCoeff[0] = y[0];
outEstimator->degree = 0;
outEstimator->confidence = 1;
return true;
}
// --- VelocityControl ---
const nsecs_t VelocityControl::STOP_TIME;
VelocityControl::VelocityControl() {
reset();
}
void VelocityControl::setParameters(const VelocityControlParameters& parameters) {
mParameters = parameters;
reset();
}
void VelocityControl::reset() {
mLastMovementTime = LLONG_MIN;
mRawPosition.x = 0;
mRawPosition.y = 0;
mVelocityTracker.clear();
}
void VelocityControl::move(nsecs_t eventTime, float* deltaX, float* deltaY) {
if ((deltaX && *deltaX) || (deltaY && *deltaY)) {
if (eventTime >= mLastMovementTime + STOP_TIME) {
#if DEBUG_ACCELERATION
ALOGD("VelocityControl: stopped, last movement was %0.3fms ago",
(eventTime - mLastMovementTime) * 0.000001f);
#endif
reset();
}
mLastMovementTime = eventTime;
if (deltaX) {
mRawPosition.x += *deltaX;
}
if (deltaY) {
mRawPosition.y += *deltaY;
}
mVelocityTracker.addMovement(eventTime, BitSet32(BitSet32::valueForBit(0)), &mRawPosition);
float vx, vy;
float scale = mParameters.scale;
if (mVelocityTracker.getVelocity(0, &vx, &vy)) {
float speed = hypotf(vx, vy) * scale;
if (speed >= mParameters.highThreshold) {
// Apply full acceleration above the high speed threshold.
scale *= mParameters.acceleration;
} else if (speed > mParameters.lowThreshold) {
// Linearly interpolate the acceleration to apply between the low and high
// speed thresholds.
scale *= 1 + (speed - mParameters.lowThreshold)
/ (mParameters.highThreshold - mParameters.lowThreshold)
* (mParameters.acceleration - 1);
}
#if DEBUG_ACCELERATION
ALOGD("VelocityControl(%0.3f, %0.3f, %0.3f, %0.3f): "
"vx=%0.3f, vy=%0.3f, speed=%0.3f, accel=%0.3f",
mParameters.scale, mParameters.lowThreshold, mParameters.highThreshold,
mParameters.acceleration,
vx, vy, speed, scale / mParameters.scale);
#endif
} else {
#if DEBUG_ACCELERATION
ALOGD("VelocityControl(%0.3f, %0.3f, %0.3f, %0.3f): unknown velocity",
mParameters.scale, mParameters.lowThreshold, mParameters.highThreshold,
mParameters.acceleration);
#endif
}
if (deltaX) {
*deltaX *= scale;
}
if (deltaY) {
*deltaY *= scale;
}
}
}
} // namespace android

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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "VelocityControl"
//#define LOG_NDEBUG 0
// Log debug messages about acceleration.
#define DEBUG_ACCELERATION 0
#include <math.h>
#include <limits.h>
#include <androidfw/VelocityControl.h>
#include <utils/BitSet.h>
#include <utils/Timers.h>
namespace android {
// --- VelocityControl ---
const nsecs_t VelocityControl::STOP_TIME;
VelocityControl::VelocityControl() {
reset();
}
void VelocityControl::setParameters(const VelocityControlParameters& parameters) {
mParameters = parameters;
reset();
}
void VelocityControl::reset() {
mLastMovementTime = LLONG_MIN;
mRawPosition.x = 0;
mRawPosition.y = 0;
mVelocityTracker.clear();
}
void VelocityControl::move(nsecs_t eventTime, float* deltaX, float* deltaY) {
if ((deltaX && *deltaX) || (deltaY && *deltaY)) {
if (eventTime >= mLastMovementTime + STOP_TIME) {
#if DEBUG_ACCELERATION
ALOGD("VelocityControl: stopped, last movement was %0.3fms ago",
(eventTime - mLastMovementTime) * 0.000001f);
#endif
reset();
}
mLastMovementTime = eventTime;
if (deltaX) {
mRawPosition.x += *deltaX;
}
if (deltaY) {
mRawPosition.y += *deltaY;
}
mVelocityTracker.addMovement(eventTime, BitSet32(BitSet32::valueForBit(0)), &mRawPosition);
float vx, vy;
float scale = mParameters.scale;
if (mVelocityTracker.getVelocity(0, &vx, &vy)) {
float speed = hypotf(vx, vy) * scale;
if (speed >= mParameters.highThreshold) {
// Apply full acceleration above the high speed threshold.
scale *= mParameters.acceleration;
} else if (speed > mParameters.lowThreshold) {
// Linearly interpolate the acceleration to apply between the low and high
// speed thresholds.
scale *= 1 + (speed - mParameters.lowThreshold)
/ (mParameters.highThreshold - mParameters.lowThreshold)
* (mParameters.acceleration - 1);
}
#if DEBUG_ACCELERATION
ALOGD("VelocityControl(%0.3f, %0.3f, %0.3f, %0.3f): "
"vx=%0.3f, vy=%0.3f, speed=%0.3f, accel=%0.3f",
mParameters.scale, mParameters.lowThreshold, mParameters.highThreshold,
mParameters.acceleration,
vx, vy, speed, scale / mParameters.scale);
#endif
} else {
#if DEBUG_ACCELERATION
ALOGD("VelocityControl(%0.3f, %0.3f, %0.3f, %0.3f): unknown velocity",
mParameters.scale, mParameters.lowThreshold, mParameters.highThreshold,
mParameters.acceleration);
#endif
}
if (deltaX) {
*deltaX *= scale;
}
if (deltaY) {
*deltaY *= scale;
}
}
}
} // namespace android

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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "VelocityTracker"
//#define LOG_NDEBUG 0
// Log debug messages about velocity tracking.
#define DEBUG_VELOCITY 0
// Log debug messages about least squares fitting.
#define DEBUG_LEAST_SQUARES 0
#include <math.h>
#include <limits.h>
#include <androidfw/VelocityTracker.h>
#include <utils/BitSet.h>
#include <utils/String8.h>
#include <utils/Timers.h>
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) {
float r = 0;
while (m--) {
r += *(a++) * *(b++);
}
return r;
}
static inline float vectorNorm(const float* a, uint32_t m) {
float r = 0;
while (m--) {
float t = *(a++);
r += t * t;
}
return sqrtf(r);
}
#if DEBUG_LEAST_SQUARES || DEBUG_VELOCITY
static String8 vectorToString(const float* a, uint32_t m) {
String8 str;
str.append("[");
while (m--) {
str.appendFormat(" %f", *(a++));
if (m) {
str.append(",");
}
}
str.append(" ]");
return str;
}
static String8 matrixToString(const float* a, uint32_t m, uint32_t n, bool rowMajor) {
String8 str;
str.append("[");
for (size_t i = 0; i < m; i++) {
if (i) {
str.append(",");
}
str.append(" [");
for (size_t j = 0; j < n; j++) {
if (j) {
str.append(",");
}
str.appendFormat(" %f", a[rowMajor ? i * n + j : j * m + i]);
}
str.append(" ]");
}
str.append(" ]");
return str;
}
#endif
VelocityTracker::VelocityTracker() {
clear();
}
void VelocityTracker::clear() {
mIndex = 0;
mMovements[0].idBits.clear();
mActivePointerId = -1;
}
void VelocityTracker::clearPointers(BitSet32 idBits) {
BitSet32 remainingIdBits(mMovements[mIndex].idBits.value & ~idBits.value);
mMovements[mIndex].idBits = remainingIdBits;
if (mActivePointerId >= 0 && idBits.hasBit(mActivePointerId)) {
mActivePointerId = !remainingIdBits.isEmpty() ? remainingIdBits.firstMarkedBit() : -1;
}
}
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];
}
if (mActivePointerId < 0 || !idBits.hasBit(mActivePointerId)) {
mActivePointerId = count != 0 ? idBits.firstMarkedBit() : -1;
}
#if DEBUG_VELOCITY
ALOGD("VelocityTracker: addMovement eventTime=%lld, idBits=0x%08x, activePointerId=%d",
eventTime, idBits.value, mActivePointerId);
for (BitSet32 iterBits(idBits); !iterBits.isEmpty(); ) {
uint32_t id = iterBits.firstMarkedBit();
uint32_t index = idBits.getIndexOfBit(id);
iterBits.clearBit(id);
Estimator estimator;
getEstimator(id, DEFAULT_DEGREE, DEFAULT_HORIZON, &estimator);
ALOGD(" %d: position (%0.3f, %0.3f), "
"estimator (degree=%d, xCoeff=%s, yCoeff=%s, confidence=%f)",
id, positions[index].x, positions[index].y,
int(estimator.degree),
vectorToString(estimator.xCoeff, estimator.degree).string(),
vectorToString(estimator.yCoeff, estimator.degree).string(),
estimator.confidence);
}
#endif
}
void VelocityTracker::addMovement(const MotionEvent* event) {
int32_t actionMasked = event->getActionMasked();
switch (actionMasked) {
case AMOTION_EVENT_ACTION_DOWN:
case AMOTION_EVENT_ACTION_HOVER_ENTER:
// Clear all pointers on down before adding the new movement.
clear();
break;
case AMOTION_EVENT_ACTION_POINTER_DOWN: {
// Start a new movement trace for a pointer that just went down.
// We do this on down instead of on up because the client may want to query the
// final velocity for a pointer that just went up.
BitSet32 downIdBits;
downIdBits.markBit(event->getPointerId(event->getActionIndex()));
clearPointers(downIdBits);
break;
}
case AMOTION_EVENT_ACTION_MOVE:
case AMOTION_EVENT_ACTION_HOVER_MOVE:
break;
default:
// Ignore all other actions because they do not convey any new information about
// pointer movement. We also want to preserve the last known velocity of the pointers.
// Note that ACTION_UP and ACTION_POINTER_UP always report the last known position
// of the pointers that went up. ACTION_POINTER_UP does include the new position of
// pointers that remained down but we will also receive an ACTION_MOVE with this
// information if any of them actually moved. Since we don't know how many pointers
// will be going up at once it makes sense to just wait for the following ACTION_MOVE
// before adding the movement.
return;
}
size_t pointerCount = event->getPointerCount();
if (pointerCount > MAX_POINTERS) {
pointerCount = MAX_POINTERS;
}
BitSet32 idBits;
for (size_t i = 0; i < pointerCount; i++) {
idBits.markBit(event->getPointerId(i));
}
nsecs_t eventTime;
Position positions[pointerCount];
size_t historySize = event->getHistorySize();
for (size_t h = 0; h < historySize; h++) {
eventTime = event->getHistoricalEventTime(h);
for (size_t i = 0; i < pointerCount; i++) {
positions[i].x = event->getHistoricalX(i, h);
positions[i].y = event->getHistoricalY(i, h);
}
addMovement(eventTime, idBits, positions);
}
eventTime = event->getEventTime();
for (size_t i = 0; i < pointerCount; i++) {
positions[i].x = event->getX(i);
positions[i].y = event->getY(i);
}
addMovement(eventTime, idBits, positions);
}
/**
* Solves a linear least squares problem to obtain a N degree polynomial that fits
* the specified input data as nearly as possible.
*
* Returns true if a solution is found, false otherwise.
*
* The input consists of two vectors of data points X and Y with indices 0..m-1.
* The output is a vector B with indices 0..n-1 that describes a polynomial
* that fits the data, such the sum of abs(Y[i] - (B[0] + B[1] X[i] + B[2] X[i]^2 ... B[n] X[i]^n))
* for all i between 0 and m-1 is minimized.
*
* That is to say, the function that generated the input data can be approximated
* by y(x) ~= B[0] + B[1] x + B[2] x^2 + ... + B[n] x^n.
*
* The coefficient of determination (R^2) is also returned to describe the goodness
* of fit of the model for the given data. It is a value between 0 and 1, where 1
* indicates perfect correspondence.
*
* This function first expands the X vector to a m by n matrix A such that
* A[i][0] = 1, A[i][1] = X[i], A[i][2] = X[i]^2, ..., A[i][n] = X[i]^n.
*
* Then it calculates the QR decomposition of A yielding an m by m orthonormal matrix Q
* and an m by n upper triangular matrix R. Because R is upper triangular (lower
* part is all zeroes), we can simplify the decomposition into an m by n matrix
* Q1 and a n by n matrix R1 such that A = Q1 R1.
*
* Finally we solve the system of linear equations given by R1 B = (Qtranspose Y)
* to find B.
*
* For efficiency, we lay out A and Q column-wise in memory because we frequently
* operate on the column vectors. Conversely, we lay out R row-wise.
*
* http://en.wikipedia.org/wiki/Numerical_methods_for_linear_least_squares
* http://en.wikipedia.org/wiki/Gram-Schmidt
*/
static bool solveLeastSquares(const float* x, const float* y, uint32_t m, uint32_t n,
float* outB, float* outDet) {
#if DEBUG_LEAST_SQUARES
ALOGD("solveLeastSquares: m=%d, n=%d, x=%s, y=%s", int(m), int(n),
vectorToString(x, m).string(), vectorToString(y, m).string());
#endif
// Expand the X vector to a matrix A.
float a[n][m]; // column-major order
for (uint32_t h = 0; h < m; h++) {
a[0][h] = 1;
for (uint32_t i = 1; i < n; i++) {
a[i][h] = a[i - 1][h] * x[h];
}
}
#if DEBUG_LEAST_SQUARES
ALOGD(" - a=%s", matrixToString(&a[0][0], m, n, false /*rowMajor*/).string());
#endif
// Apply the Gram-Schmidt process to A to obtain its QR decomposition.
float q[n][m]; // orthonormal basis, column-major order
float r[n][n]; // upper triangular matrix, row-major order
for (uint32_t j = 0; j < n; j++) {
for (uint32_t h = 0; h < m; h++) {
q[j][h] = a[j][h];
}
for (uint32_t i = 0; i < j; i++) {
float dot = vectorDot(&q[j][0], &q[i][0], m);
for (uint32_t h = 0; h < m; h++) {
q[j][h] -= dot * q[i][h];
}
}
float norm = vectorNorm(&q[j][0], m);
if (norm < 0.000001f) {
// vectors are linearly dependent or zero so no solution
#if DEBUG_LEAST_SQUARES
ALOGD(" - no solution, norm=%f", norm);
#endif
return false;
}
float invNorm = 1.0f / norm;
for (uint32_t h = 0; h < m; h++) {
q[j][h] *= invNorm;
}
for (uint32_t i = 0; i < n; i++) {
r[j][i] = i < j ? 0 : vectorDot(&q[j][0], &a[i][0], m);
}
}
#if DEBUG_LEAST_SQUARES
ALOGD(" - q=%s", matrixToString(&q[0][0], m, n, false /*rowMajor*/).string());
ALOGD(" - r=%s", matrixToString(&r[0][0], n, n, true /*rowMajor*/).string());
// calculate QR, if we factored A correctly then QR should equal A
float qr[n][m];
for (uint32_t h = 0; h < m; h++) {
for (uint32_t i = 0; i < n; i++) {
qr[i][h] = 0;
for (uint32_t j = 0; j < n; j++) {
qr[i][h] += q[j][h] * r[j][i];
}
}
}
ALOGD(" - qr=%s", matrixToString(&qr[0][0], m, n, false /*rowMajor*/).string());
#endif
// Solve R B = Qt Y to find B. This is easy because R is upper triangular.
// We just work from bottom-right to top-left calculating B's coefficients.
for (uint32_t i = n; i-- != 0; ) {
outB[i] = vectorDot(&q[i][0], y, m);
for (uint32_t j = n - 1; j > i; j--) {
outB[i] -= r[i][j] * outB[j];
}
outB[i] /= r[i][i];
}
#if DEBUG_LEAST_SQUARES
ALOGD(" - b=%s", vectorToString(outB, n).string());
#endif
// Calculate the coefficient of determination as 1 - (SSerr / SStot) where
// SSerr is the residual sum of squares (squared variance of the error),
// and SStot is the total sum of squares (squared variance of the data).
float ymean = 0;
for (uint32_t h = 0; h < m; h++) {
ymean += y[h];
}
ymean /= m;
float sserr = 0;
float sstot = 0;
for (uint32_t h = 0; h < m; h++) {
float err = y[h] - outB[0];
float term = 1;
for (uint32_t i = 1; i < n; i++) {
term *= x[h];
err -= term * outB[i];
}
sserr += err * err;
float var = y[h] - ymean;
sstot += var * var;
}
*outDet = sstot > 0.000001f ? 1.0f - (sserr / sstot) : 1;
#if DEBUG_LEAST_SQUARES
ALOGD(" - sserr=%f", sserr);
ALOGD(" - sstot=%f", sstot);
ALOGD(" - det=%f", *outDet);
#endif
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 {
outEstimator->clear();
// Iterate over movement samples in reverse time order and collect samples.
float x[HISTORY_SIZE];
float y[HISTORY_SIZE];
float time[HISTORY_SIZE];
uint32_t m = 0;
uint32_t index = mIndex;
const Movement& newestMovement = mMovements[mIndex];
do {
const Movement& movement = mMovements[index];
if (!movement.idBits.hasBit(id)) {
break;
}
nsecs_t age = newestMovement.eventTime - movement.eventTime;
if (age > horizon) {
break;
}
const Position& position = movement.getPosition(id);
x[m] = position.x;
y[m] = position.y;
time[m] = -age * 0.000000001f;
index = (index == 0 ? HISTORY_SIZE : index) - 1;
} while (++m < HISTORY_SIZE);
if (m == 0) {
return false; // no data
}
// Calculate a least squares polynomial fit.
if (degree > Estimator::MAX_DEGREE) {
degree = Estimator::MAX_DEGREE;
}
if (degree > m - 1) {
degree = m - 1;
}
if (degree >= 1) {
float xdet, ydet;
uint32_t n = degree + 1;
if (solveLeastSquares(time, x, m, n, outEstimator->xCoeff, &xdet)
&& solveLeastSquares(time, y, m, n, outEstimator->yCoeff, &ydet)) {
outEstimator->degree = degree;
outEstimator->confidence = xdet * ydet;
#if DEBUG_LEAST_SQUARES
ALOGD("estimate: degree=%d, xCoeff=%s, yCoeff=%s, confidence=%f",
int(outEstimator->degree),
vectorToString(outEstimator->xCoeff, n).string(),
vectorToString(outEstimator->yCoeff, n).string(),
outEstimator->confidence);
#endif
return true;
}
}
// No velocity data available for this pointer, but we do have its current position.
outEstimator->xCoeff[0] = x[0];
outEstimator->yCoeff[0] = y[0];
outEstimator->degree = 0;
outEstimator->confidence = 1;
return true;
}
} // namespace android

2
services/input/InputReader.h
View File

@@ -22,6 +22,8 @@
#include "InputListener.h"
#include <androidfw/Input.h>
#include <androidfw/VelocityControl.h>
#include <androidfw/VelocityTracker.h>
#include <ui/DisplayInfo.h>
#include <utils/KeyedVector.h>
#include <utils/threads.h>

1
services/input/PointerController.h
View File

@@ -21,6 +21,7 @@
#include <ui/DisplayInfo.h>
#include <androidfw/Input.h>
#include <utils/BitSet.h>
#include <utils/RefBase.h>
#include <utils/Looper.h>
#include <utils/String8.h>