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-rw-r--r--native/jni/src/proximity_info_state.cpp747
1 files changed, 622 insertions, 125 deletions
diff --git a/native/jni/src/proximity_info_state.cpp b/native/jni/src/proximity_info_state.cpp
index 392ec8194..db79bb616 100644
--- a/native/jni/src/proximity_info_state.cpp
+++ b/native/jni/src/proximity_info_state.cpp
@@ -15,6 +15,7 @@
*/
#include <cstring> // for memset()
+#include <sstream> // for debug prints
#include <stdint.h>
#define LOG_TAG "LatinIME: proximity_info_state.cpp"
@@ -33,7 +34,7 @@ const float ProximityInfoState::NOT_A_DISTANCE_FLOAT = -1.0f;
const int ProximityInfoState::NOT_A_CODE = -1;
void ProximityInfoState::initInputParams(const int pointerId, const float maxPointToKeyLength,
- const ProximityInfo *proximityInfo, const int32_t *const inputCodes, const int inputSize,
+ const ProximityInfo *proximityInfo, const int *const inputCodes, const int inputSize,
const int *const xCoordinates, const int *const yCoordinates, const int *const times,
const int *const pointerIds, const bool isGeometric) {
@@ -62,7 +63,7 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
// - mNormalizedSquaredDistances
// TODO: Merge
for (int i = 0; i < inputSize; ++i) {
- const int32_t primaryKey = inputCodes[i];
+ const int primaryKey = inputCodes[i];
const int x = xCoordinates[i];
const int y = yCoordinates[i];
int *proximities = &mInputCodes[i * MAX_PROXIMITY_CHARS_SIZE_INTERNAL];
@@ -104,7 +105,10 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
mLengthCache.clear();
mDistanceCache.clear();
mNearKeysVector.clear();
+ mSearchKeysVector.clear();
mRelativeSpeeds.clear();
+ mCharProbabilities.clear();
+ mDirections.clear();
}
if (DEBUG_GEO_FULL) {
AKLOGI("Init ProximityInfoState: reused points = %d, last input size = %d",
@@ -130,6 +134,10 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
NearKeysDistanceMap *currentNearKeysDistances = &nearKeysDistances[0];
NearKeysDistanceMap *prevNearKeysDistances = &nearKeysDistances[1];
NearKeysDistanceMap *prevPrevNearKeysDistances = &nearKeysDistances[2];
+ // "sumAngle" is accumulated by each angle of input points. And when "sumAngle" exceeds
+ // the threshold we save that point, reset sumAngle. This aims to keep the figure of
+ // the curve.
+ float sumAngle = 0.0f;
for (int i = pushTouchPointStartIndex; i <= lastInputIndex; ++i) {
// Assuming pointerId == 0 if pointerIds is null.
@@ -138,13 +146,22 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
AKLOGI("Init ProximityInfoState: (%d)PID = %d", i, pid);
}
if (pointerId == pid) {
- const int c = isGeometric ? NOT_A_COORDINATE : getPrimaryCharAt(i);
+ const int c = isGeometric ? NOT_A_COORDINATE : getPrimaryCodePointAt(i);
const int x = proximityOnly ? NOT_A_COORDINATE : xCoordinates[i];
const int y = proximityOnly ? NOT_A_COORDINATE : yCoordinates[i];
const int time = times ? times[i] : -1;
+
+ if (i > 1) {
+ const float prevAngle = getAngle(xCoordinates[i - 2], yCoordinates[i - 2],
+ xCoordinates[i - 1], yCoordinates[i - 1]);
+ const float currentAngle =
+ getAngle(xCoordinates[i - 1], yCoordinates[i - 1], x, y);
+ sumAngle += getAngleDiff(prevAngle, currentAngle);
+ }
+
if (pushTouchPoint(i, c, x, y, time, isGeometric /* do sampling */,
- i == lastInputIndex, currentNearKeysDistances, prevNearKeysDistances,
- prevPrevNearKeysDistances)) {
+ i == lastInputIndex, sumAngle, currentNearKeysDistances,
+ prevNearKeysDistances, prevPrevNearKeysDistances)) {
// Previous point information was popped.
NearKeysDistanceMap *tmp = prevNearKeysDistances;
prevNearKeysDistances = currentNearKeysDistances;
@@ -154,6 +171,7 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
prevPrevNearKeysDistances = prevNearKeysDistances;
prevNearKeysDistances = currentNearKeysDistances;
currentNearKeysDistances = tmp;
+ sumAngle = 0.0f;
}
}
}
@@ -161,43 +179,68 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
}
if (mInputSize > 0 && isGeometric) {
- int sumDuration = mTimes.back() - mTimes.front();
- int sumLength = mLengthCache.back() - mLengthCache.front();
- float averageSpeed = static_cast<float>(sumLength) / static_cast<float>(sumDuration);
+ // Relative speed calculation.
+ const int sumDuration = mTimes.back() - mTimes.front();
+ const int sumLength = mLengthCache.back() - mLengthCache.front();
+ const float averageSpeed = static_cast<float>(sumLength) / static_cast<float>(sumDuration);
mRelativeSpeeds.resize(mInputSize);
for (int i = lastSavedInputSize; i < mInputSize; ++i) {
const int index = mInputIndice[i];
int length = 0;
int duration = 0;
- if (index == 0 && index < inputSize - 1) {
- length = getDistanceInt(xCoordinates[index], yCoordinates[index],
- xCoordinates[index + 1], yCoordinates[index + 1]);
- duration = times[index + 1] - times[index];
- } else if (index == inputSize - 1 && index > 0) {
- length = getDistanceInt(xCoordinates[index - 1], yCoordinates[index - 1],
- xCoordinates[index], yCoordinates[index]);
- duration = times[index] - times[index - 1];
- } else if (0 < index && index < inputSize - 1) {
- length = getDistanceInt(xCoordinates[index - 1], yCoordinates[index - 1],
- xCoordinates[index], yCoordinates[index])
- + getDistanceInt(xCoordinates[index], yCoordinates[index],
- xCoordinates[index + 1], yCoordinates[index + 1]);
- duration = times[index + 1] - times[index - 1];
+
+ // Calculate velocity by using distances and durations of
+ // NUM_POINTS_FOR_SPEED_CALCULATION points for both forward and backward.
+ static const int NUM_POINTS_FOR_SPEED_CALCULATION = 2;
+ for (int j = index; j < min(inputSize - 1, index + NUM_POINTS_FOR_SPEED_CALCULATION);
+ ++j) {
+ if (i < mInputSize - 1 && j >= mInputIndice[i + 1]) {
+ break;
+ }
+ length += getDistanceInt(xCoordinates[j], yCoordinates[j],
+ xCoordinates[j + 1], yCoordinates[j + 1]);
+ duration += times[j + 1] - times[j];
+ }
+ for (int j = index - 1; j >= max(0, index - NUM_POINTS_FOR_SPEED_CALCULATION); --j) {
+ if (i > 0 && j < mInputIndice[i - 1]) {
+ break;
+ }
+ length += getDistanceInt(xCoordinates[j], yCoordinates[j],
+ xCoordinates[j + 1], yCoordinates[j + 1]);
+ duration += times[j + 1] - times[j];
+ }
+ if (duration == 0 || sumDuration == 0) {
+ // Cannot calculate speed; thus, it gives an average value (1.0);
+ mRelativeSpeeds[i] = 1.0f;
} else {
- length = 0;
- duration = 1;
+ const float speed = static_cast<float>(length) / static_cast<float>(duration);
+ mRelativeSpeeds[i] = speed / averageSpeed;
}
- const float speed = static_cast<float>(length) / static_cast<float>(duration);
- mRelativeSpeeds[i] = speed / averageSpeed;
+ }
+
+ // Direction calculation.
+ mDirections.resize(mInputSize - 1);
+ for (int i = max(0, lastSavedInputSize - 1); i < mInputSize - 1; ++i) {
+ mDirections[i] = getDirection(i, i + 1);
+ }
+
+ }
+
+ if (DEBUG_GEO_FULL) {
+ for (int i = 0; i < mInputSize; ++i) {
+ AKLOGI("Sampled(%d): x = %d, y = %d, time = %d", i, mInputXs[i], mInputYs[i],
+ mTimes[i]);
}
}
if (mInputSize > 0) {
const int keyCount = mProximityInfo->getKeyCount();
mNearKeysVector.resize(mInputSize);
+ mSearchKeysVector.resize(mInputSize);
mDistanceCache.resize(mInputSize * keyCount);
for (int i = lastSavedInputSize; i < mInputSize; ++i) {
mNearKeysVector[i].reset();
+ mSearchKeysVector[i].reset();
static const float NEAR_KEY_NORMALIZED_SQUARED_THRESHOLD = 4.0f;
for (int k = 0; k < keyCount; ++k) {
const int index = i * keyCount + k;
@@ -207,29 +250,53 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
mProximityInfo->getNormalizedSquaredDistanceFromCenterFloatG(k, x, y);
mDistanceCache[index] = normalizedSquaredDistance;
if (normalizedSquaredDistance < NEAR_KEY_NORMALIZED_SQUARED_THRESHOLD) {
- mNearKeysVector[i].set(k, 1);
+ mNearKeysVector[i][k] = true;
}
}
}
+ if (isGeometric) {
+ // updates probabilities of skipping or mapping each key for all points.
+ updateAlignPointProbabilities(lastSavedInputSize);
- static const float READ_FORWORD_LENGTH_SCALE = 0.95f;
- const int readForwordLength = static_cast<int>(
- hypotf(mProximityInfo->getKeyboardWidth(), mProximityInfo->getKeyboardHeight())
- * READ_FORWORD_LENGTH_SCALE);
- for (int i = 0; i < mInputSize; ++i) {
- if (DEBUG_GEO_FULL) {
- AKLOGI("Sampled(%d): x = %d, y = %d, time = %d", i, mInputXs[i], mInputYs[i],
- mTimes[i]);
- }
- for (int j = max(i + 1, lastSavedInputSize); j < mInputSize; ++j) {
- if (mLengthCache[j] - mLengthCache[i] >= readForwordLength) {
- break;
+ static const float READ_FORWORD_LENGTH_SCALE = 0.95f;
+ const int readForwordLength = static_cast<int>(
+ hypotf(mProximityInfo->getKeyboardWidth(), mProximityInfo->getKeyboardHeight())
+ * READ_FORWORD_LENGTH_SCALE);
+ for (int i = 0; i < mInputSize; ++i) {
+ if (i >= lastSavedInputSize) {
+ mSearchKeysVector[i].reset();
+ }
+ for (int j = max(i, lastSavedInputSize); j < mInputSize; ++j) {
+ if (mLengthCache[j] - mLengthCache[i] >= readForwordLength) {
+ break;
+ }
+ mSearchKeysVector[i] |= mNearKeysVector[j];
}
- mNearKeysVector[i] |= mNearKeysVector[j];
}
}
}
+ if (DEBUG_SAMPLING_POINTS) {
+ std::stringstream originalX, originalY, sampledX, sampledY;
+ for (int i = 0; i < inputSize; ++i) {
+ originalX << xCoordinates[i];
+ originalY << yCoordinates[i];
+ if (i != inputSize - 1) {
+ originalX << ";";
+ originalY << ";";
+ }
+ }
+ for (int i = 0; i < mInputSize; ++i) {
+ sampledX << mInputXs[i];
+ sampledY << mInputYs[i];
+ if (i != mInputSize - 1) {
+ sampledX << ";";
+ sampledY << ";";
+ }
+ }
+ AKLOGI("\n%s, %s,\n%s, %s,\n", originalX.str().c_str(), originalY.str().c_str(),
+ sampledX.str().c_str(), sampledY.str().c_str());
+ }
// end
///////////////////////
@@ -239,12 +306,12 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
&& xCoordinates && yCoordinates;
if (!isGeometric && pointerId == 0) {
for (int i = 0; i < inputSize; ++i) {
- mPrimaryInputWord[i] = getPrimaryCharAt(i);
+ mPrimaryInputWord[i] = getPrimaryCodePointAt(i);
}
for (int i = 0; i < mInputSize && mTouchPositionCorrectionEnabled; ++i) {
- const int *proximityChars = getProximityCharsAt(i);
- const int primaryKey = proximityChars[0];
+ const int *proximityCodePoints = getProximityCodePointsAt(i);
+ const int primaryKey = proximityCodePoints[0];
const int x = xCoordinates[i];
const int y = yCoordinates[i];
if (DEBUG_PROXIMITY_CHARS) {
@@ -252,11 +319,12 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
a += 0;
AKLOGI("--- Primary = %c, x = %d, y = %d", primaryKey, x, y);
}
- for (int j = 0; j < MAX_PROXIMITY_CHARS_SIZE_INTERNAL && proximityChars[j] > 0; ++j) {
- const int currentChar = proximityChars[j];
+ for (int j = 0; j < MAX_PROXIMITY_CHARS_SIZE_INTERNAL && proximityCodePoints[j] > 0;
+ ++j) {
+ const int currentCodePoint = proximityCodePoints[j];
const float squaredDistance =
hasInputCoordinates() ? calculateNormalizedSquaredDistance(
- mProximityInfo->getKeyIndexOf(currentChar), i) :
+ mProximityInfo->getKeyIndexOf(currentCodePoint), i) :
NOT_A_DISTANCE_FLOAT;
if (squaredDistance >= 0.0f) {
mNormalizedSquaredDistances[i * MAX_PROXIMITY_CHARS_SIZE_INTERNAL + j] =
@@ -267,7 +335,7 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
PROXIMITY_CHAR_WITHOUT_DISTANCE_INFO;
}
if (DEBUG_PROXIMITY_CHARS) {
- AKLOGI("--- Proximity (%d) = %c", j, currentChar);
+ AKLOGI("--- Proximity (%d) = %c", j, currentCodePoint);
}
}
}
@@ -294,7 +362,7 @@ bool ProximityInfoState::checkAndReturnIsContinuationPossible(const int inputSiz
// the given point and the nearest key position.
float ProximityInfoState::updateNearKeysDistances(const int x, const int y,
NearKeysDistanceMap *const currentNearKeysDistances) {
- static const float NEAR_KEY_THRESHOLD = 4.0f;
+ static const float NEAR_KEY_THRESHOLD = 2.0f;
currentNearKeysDistances->clear();
const int keyCount = mProximityInfo->getKeyCount();
@@ -332,64 +400,49 @@ bool ProximityInfoState::isPrevLocalMin(const NearKeysDistanceMap *const current
// Calculating a point score that indicates usefulness of the point.
float ProximityInfoState::getPointScore(
const int x, const int y, const int time, const bool lastPoint, const float nearest,
- const NearKeysDistanceMap *const currentNearKeysDistances,
+ const float sumAngle, const NearKeysDistanceMap *const currentNearKeysDistances,
const NearKeysDistanceMap *const prevNearKeysDistances,
const NearKeysDistanceMap *const prevPrevNearKeysDistances) const {
static const int DISTANCE_BASE_SCALE = 100;
- static const int SAVE_DISTANCE_SCALE = 200;
- static const int SKIP_DISTANCE_SCALE = 25;
- static const int CHECK_LOCALMIN_DISTANCE_THRESHOLD_SCALE = 40;
- static const int STRAIGHT_SKIP_DISTANCE_THRESHOLD_SCALE = 50;
- static const int CORNER_CHECK_DISTANCE_THRESHOLD_SCALE = 27;
- static const float SAVE_DISTANCE_SCORE = 2.0f;
- static const float SKIP_DISTANCE_SCORE = -1.0f;
- static const float CHECK_LOCALMIN_DISTANCE_SCORE = -1.0f;
- static const float STRAIGHT_ANGLE_THRESHOLD = M_PI_F / 36.0f;
- static const float STRAIGHT_SKIP_NEAREST_DISTANCE_THRESHOLD = 0.5f;
- static const float STRAIGHT_SKIP_SCORE = -1.0f;
- static const float CORNER_ANGLE_THRESHOLD = M_PI_F / 2.0f;
+ static const float NEAR_KEY_THRESHOLD = 0.6f;
+ static const int CORNER_CHECK_DISTANCE_THRESHOLD_SCALE = 25;
+ static const float NOT_LOCALMIN_DISTANCE_SCORE = -1.0f;
+ static const float LOCALMIN_DISTANCE_AND_NEAR_TO_KEY_SCORE = 1.0f;
+ static const float CORNER_ANGLE_THRESHOLD = M_PI_F * 2.0f / 3.0f;
+ static const float CORNER_SUM_ANGLE_THRESHOLD = M_PI_F / 4.0f;
static const float CORNER_SCORE = 1.0f;
- const std::size_t size = mInputXs.size();
- if (size <= 1) {
+ const size_t size = mInputXs.size();
+ // If there is only one point, add this point. Besides, if the previous point's distance map
+ // is empty, we re-compute nearby keys distances from the current point.
+ // Note that the current point is the first point in the incremental input that needs to
+ // be re-computed.
+ if (size <= 1 || prevNearKeysDistances->empty()) {
return 0.0f;
}
+
const int baseSampleRate = mProximityInfo->getMostCommonKeyWidth();
- const int distNext = getDistanceInt(x, y, mInputXs.back(), mInputYs.back())
- * DISTANCE_BASE_SCALE;
const int distPrev = getDistanceInt(mInputXs.back(), mInputYs.back(),
mInputXs[size - 2], mInputYs[size - 2]) * DISTANCE_BASE_SCALE;
float score = 0.0f;
- // Sum of distances
- if (distPrev + distNext > baseSampleRate * SAVE_DISTANCE_SCALE) {
- score += SAVE_DISTANCE_SCORE;
- }
- // Distance
- if (distPrev < baseSampleRate * SKIP_DISTANCE_SCALE) {
- score += SKIP_DISTANCE_SCORE;
- }
// Location
- if (distPrev < baseSampleRate * CHECK_LOCALMIN_DISTANCE_THRESHOLD_SCALE) {
- if (!isPrevLocalMin(currentNearKeysDistances, prevNearKeysDistances,
- prevPrevNearKeysDistances)) {
- score += CHECK_LOCALMIN_DISTANCE_SCORE;
- }
+ if (!isPrevLocalMin(currentNearKeysDistances, prevNearKeysDistances,
+ prevPrevNearKeysDistances)) {
+ score += NOT_LOCALMIN_DISTANCE_SCORE;
+ } else if (nearest < NEAR_KEY_THRESHOLD) {
+ // Promote points nearby keys
+ score += LOCALMIN_DISTANCE_AND_NEAR_TO_KEY_SCORE;
}
// Angle
const float angle1 = getAngle(x, y, mInputXs.back(), mInputYs.back());
const float angle2 = getAngle(mInputXs.back(), mInputYs.back(),
mInputXs[size - 2], mInputYs[size - 2]);
const float angleDiff = getAngleDiff(angle1, angle2);
- // Skip straight
- if (nearest > STRAIGHT_SKIP_NEAREST_DISTANCE_THRESHOLD
- && distPrev < baseSampleRate * STRAIGHT_SKIP_DISTANCE_THRESHOLD_SCALE
- && angleDiff < STRAIGHT_ANGLE_THRESHOLD) {
- score += STRAIGHT_SKIP_SCORE;
- }
+
// Save corner
if (distPrev > baseSampleRate * CORNER_CHECK_DISTANCE_THRESHOLD_SCALE
- && angleDiff > CORNER_ANGLE_THRESHOLD) {
+ && (sumAngle > CORNER_SUM_ANGLE_THRESHOLD || angleDiff > CORNER_ANGLE_THRESHOLD)) {
score += CORNER_SCORE;
}
return score;
@@ -397,18 +450,18 @@ float ProximityInfoState::getPointScore(
// Sampling touch point and pushing information to vectors.
// Returning if previous point is popped or not.
-bool ProximityInfoState::pushTouchPoint(const int inputIndex, const int nodeChar, int x, int y,
- const int time, const bool sample, const bool isLastPoint,
+bool ProximityInfoState::pushTouchPoint(const int inputIndex, const int nodeCodePoint, int x, int y,
+ const int time, const bool sample, const bool isLastPoint, const float sumAngle,
NearKeysDistanceMap *const currentNearKeysDistances,
const NearKeysDistanceMap *const prevNearKeysDistances,
const NearKeysDistanceMap *const prevPrevNearKeysDistances) {
- static const float LAST_POINT_SKIP_DISTANCE_SCALE = 0.25f;
+ static const int LAST_POINT_SKIP_DISTANCE_SCALE = 4;
size_t size = mInputXs.size();
bool popped = false;
- if (nodeChar < 0 && sample) {
+ if (nodeCodePoint < 0 && sample) {
const float nearest = updateNearKeysDistances(x, y, currentNearKeysDistances);
- const float score = getPointScore(x, y, time, isLastPoint, nearest,
+ const float score = getPointScore(x, y, time, isLastPoint, nearest, sumAngle,
currentNearKeysDistances, prevNearKeysDistances, prevPrevNearKeysDistances);
if (score < 0) {
// Pop previous point because it would be useless.
@@ -419,42 +472,24 @@ bool ProximityInfoState::pushTouchPoint(const int inputIndex, const int nodeChar
popped = false;
}
// Check if the last point should be skipped.
- if (isLastPoint) {
- if (size > 0 && getDistanceFloat(x, y, mInputXs.back(), mInputYs.back())
- < mProximityInfo->getMostCommonKeyWidth() * LAST_POINT_SKIP_DISTANCE_SCALE) {
+ if (isLastPoint && size > 0) {
+ if (getDistanceInt(x, y, mInputXs.back(), mInputYs.back())
+ * LAST_POINT_SKIP_DISTANCE_SCALE < mProximityInfo->getMostCommonKeyWidth()) {
+ // This point is not used because it's too close to the previous point.
if (DEBUG_GEO_FULL) {
- AKLOGI("p0: size = %zd, x = %d, y = %d, lx = %d, ly = %d, dist = %f, "
- "width = %f", size, x, y, mInputXs.back(), mInputYs.back(),
- getDistanceFloat(x, y, mInputXs.back(), mInputYs.back()),
+ AKLOGI("p0: size = %zd, x = %d, y = %d, lx = %d, ly = %d, dist = %d, "
+ "width = %d", size, x, y, mInputXs.back(), mInputYs.back(),
+ getDistanceInt(x, y, mInputXs.back(), mInputYs.back()),
mProximityInfo->getMostCommonKeyWidth()
- * LAST_POINT_SKIP_DISTANCE_SCALE);
+ / LAST_POINT_SKIP_DISTANCE_SCALE);
}
return popped;
- } else if (size > 1) {
- int minChar = 0;
- float minDist = mMaxPointToKeyLength;
- for (NearKeysDistanceMap::const_iterator it = currentNearKeysDistances->begin();
- it != currentNearKeysDistances->end(); ++it) {
- if (minDist > it->second) {
- minChar = it->first;
- minDist = it->second;
- }
- }
- NearKeysDistanceMap::const_iterator itPP =
- prevNearKeysDistances->find(minChar);
- if (itPP != prevNearKeysDistances->end() && minDist > itPP->second) {
- if (DEBUG_GEO_FULL) {
- AKLOGI("p1: char = %c, minDist = %f, prevNear key minDist = %f",
- minChar, itPP->second, minDist);
- }
- return popped;
- }
}
}
}
- if (nodeChar >= 0 && (x < 0 || y < 0)) {
- const int keyId = mProximityInfo->getKeyIndexOf(nodeChar);
+ if (nodeCodePoint >= 0 && (x < 0 || y < 0)) {
+ const int keyId = mProximityInfo->getKeyIndexOf(nodeCodePoint);
if (keyId >= 0) {
x = mProximityInfo->getKeyCenterXOfKeyIdG(keyId);
y = mProximityInfo->getKeyCenterYOfKeyIdG(keyId);
@@ -503,22 +538,92 @@ int ProximityInfoState::getDuration(const int index) const {
return 0;
}
-float ProximityInfoState::getPointToKeyLength(const int inputIndex, const int codePoint,
- const float scale) const {
+float ProximityInfoState::getPointToKeyLength(const int inputIndex, const int codePoint) const {
const int keyId = mProximityInfo->getKeyIndexOf(codePoint);
if (keyId != NOT_AN_INDEX) {
const int index = inputIndex * mProximityInfo->getKeyCount() + keyId;
- return min(mDistanceCache[index] * scale, mMaxPointToKeyLength);
+ return min(mDistanceCache[index], mMaxPointToKeyLength);
}
- if (isSkippableChar(codePoint)) {
+ if (isSkippableCodePoint(codePoint)) {
return 0.0f;
}
// If the char is not a key on the keyboard then return the max length.
return MAX_POINT_TO_KEY_LENGTH;
}
+float ProximityInfoState::getPointToKeyByIdLength(const int inputIndex, const int keyId) const {
+ if (keyId != NOT_AN_INDEX) {
+ const int index = inputIndex * mProximityInfo->getKeyCount() + keyId;
+ return min(mDistanceCache[index], mMaxPointToKeyLength);
+ }
+ // If the char is not a key on the keyboard then return the max length.
+ return static_cast<float>(MAX_POINT_TO_KEY_LENGTH);
+}
+
+// In the following function, c is the current character of the dictionary word currently examined.
+// currentChars is an array containing the keys close to the character the user actually typed at
+// the same position. We want to see if c is in it: if so, then the word contains at that position
+// a character close to what the user typed.
+// What the user typed is actually the first character of the array.
+// proximityIndex is a pointer to the variable where getMatchedProximityId returns the index of c
+// in the proximity chars of the input index.
+// Notice : accented characters do not have a proximity list, so they are alone in their list. The
+// non-accented version of the character should be considered "close", but not the other keys close
+// to the non-accented version.
+ProximityType ProximityInfoState::getMatchedProximityId(const int index, const int c,
+ const bool checkProximityChars, int *proximityIndex) const {
+ const int *currentCodePoints = getProximityCodePointsAt(index);
+ const int firstCodePoint = currentCodePoints[0];
+ const int baseLowerC = toBaseLowerCase(c);
+
+ // The first char in the array is what user typed. If it matches right away, that means the
+ // user typed that same char for this pos.
+ if (firstCodePoint == baseLowerC || firstCodePoint == c) {
+ return EQUIVALENT_CHAR;
+ }
+
+ if (!checkProximityChars) return UNRELATED_CHAR;
+
+ // If the non-accented, lowercased version of that first character matches c, then we have a
+ // non-accented version of the accented character the user typed. Treat it as a close char.
+ if (toBaseLowerCase(firstCodePoint) == baseLowerC) {
+ return NEAR_PROXIMITY_CHAR;
+ }
+
+ // Not an exact nor an accent-alike match: search the list of close keys
+ int j = 1;
+ while (j < MAX_PROXIMITY_CHARS_SIZE_INTERNAL
+ && currentCodePoints[j] > ADDITIONAL_PROXIMITY_CHAR_DELIMITER_CODE) {
+ const bool matched = (currentCodePoints[j] == baseLowerC || currentCodePoints[j] == c);
+ if (matched) {
+ if (proximityIndex) {
+ *proximityIndex = j;
+ }
+ return NEAR_PROXIMITY_CHAR;
+ }
+ ++j;
+ }
+ if (j < MAX_PROXIMITY_CHARS_SIZE_INTERNAL
+ && currentCodePoints[j] == ADDITIONAL_PROXIMITY_CHAR_DELIMITER_CODE) {
+ ++j;
+ while (j < MAX_PROXIMITY_CHARS_SIZE_INTERNAL
+ && currentCodePoints[j] > ADDITIONAL_PROXIMITY_CHAR_DELIMITER_CODE) {
+ const bool matched = (currentCodePoints[j] == baseLowerC || currentCodePoints[j] == c);
+ if (matched) {
+ if (proximityIndex) {
+ *proximityIndex = j;
+ }
+ return ADDITIONAL_PROXIMITY_CHAR;
+ }
+ ++j;
+ }
+ }
+ // Was not included, signal this as an unrelated character.
+ return UNRELATED_CHAR;
+}
+
int ProximityInfoState::getSpaceY() const {
- const int keyId = mProximityInfo->getKeyIndexOf(' ');
+ const int keyId = mProximityInfo->getKeyIndexOf(KEYCODE_SPACE);
return mProximityInfo->getKeyCenterYOfKeyIdG(keyId);
}
@@ -538,8 +643,9 @@ int32_t ProximityInfoState::getAllPossibleChars(
return filterSize;
}
int newFilterSize = filterSize;
- for (int j = 0; j < mProximityInfo->getKeyCount(); ++j) {
- if (mNearKeysVector[index].test(j)) {
+ const int keyCount = mProximityInfo->getKeyCount();
+ for (int j = 0; j < keyCount; ++j) {
+ if (mSearchKeysVector[index].test(j)) {
const int32_t keyCodePoint = mProximityInfo->getCodePointOf(j);
bool insert = true;
// TODO: Avoid linear search
@@ -557,6 +663,12 @@ int32_t ProximityInfoState::getAllPossibleChars(
return newFilterSize;
}
+bool ProximityInfoState::isKeyInSerchKeysAfterIndex(const int index, const int keyId) const {
+ ASSERT(keyId >= 0);
+ ASSERT(index >= 0 && index < mInputSize);
+ return mSearchKeysVector[index].test(keyId);
+}
+
void ProximityInfoState::popInputData() {
mInputXs.pop_back();
mInputYs.pop_back();
@@ -565,4 +677,389 @@ void ProximityInfoState::popInputData() {
mInputIndice.pop_back();
}
+float ProximityInfoState::getDirection(const int index0, const int index1) const {
+ if (index0 < 0 || index0 > mInputSize - 1) {
+ return 0.0f;
+ }
+ if (index1 < 0 || index1 > mInputSize - 1) {
+ return 0.0f;
+ }
+ const int x1 = mInputXs[index0];
+ const int y1 = mInputYs[index0];
+ const int x2 = mInputXs[index1];
+ const int y2 = mInputYs[index1];
+ return getAngle(x1, y1, x2, y2);
+}
+
+float ProximityInfoState::getPointAngle(const int index) const {
+ if (index <= 0 || index >= mInputSize - 1) {
+ return 0.0f;
+ }
+ const float previousDirection = getDirection(index - 1, index);
+ const float nextDirection = getDirection(index, index + 1);
+ const float directionDiff = getAngleDiff(previousDirection, nextDirection);
+ return directionDiff;
+}
+
+float ProximityInfoState::getPointsAngle(
+ const int index0, const int index1, const int index2) const {
+ if (index0 < 0 || index0 > mInputSize - 1) {
+ return 0.0f;
+ }
+ if (index1 < 0 || index1 > mInputSize - 1) {
+ return 0.0f;
+ }
+ if (index2 < 0 || index2 > mInputSize - 1) {
+ return 0.0f;
+ }
+ const float previousDirection = getDirection(index0, index1);
+ const float nextDirection = getDirection(index1, index2);
+ return getAngleDiff(previousDirection, nextDirection);
+}
+
+float ProximityInfoState::getLineToKeyDistance(
+ const int from, const int to, const int keyId, const bool extend) const {
+ if (from < 0 || from > mInputSize - 1) {
+ return 0.0f;
+ }
+ if (to < 0 || to > mInputSize - 1) {
+ return 0.0f;
+ }
+ const int x0 = mInputXs[from];
+ const int y0 = mInputYs[from];
+ const int x1 = mInputXs[to];
+ const int y1 = mInputYs[to];
+
+ const int keyX = mProximityInfo->getKeyCenterXOfKeyIdG(keyId);
+ const int keyY = mProximityInfo->getKeyCenterYOfKeyIdG(keyId);
+
+ return pointToLineSegSquaredDistanceFloat(keyX, keyY, x0, y0, x1, y1, extend);
+}
+
+// Updates probabilities of aligning to some keys and skipping.
+// Word suggestion should be based on this probabilities.
+void ProximityInfoState::updateAlignPointProbabilities(const int start) {
+ static const float MIN_PROBABILITY = 0.000001f;
+ static const float MAX_SKIP_PROBABILITY = 0.95f;
+ static const float SKIP_FIRST_POINT_PROBABILITY = 0.01f;
+ static const float SKIP_LAST_POINT_PROBABILITY = 0.1f;
+ static const float MIN_SPEED_RATE_FOR_SKIP_PROBABILITY = 0.15f;
+ static const float SPEED_WEIGHT_FOR_SKIP_PROBABILITY = 0.9f;
+ static const float SLOW_STRAIGHT_WEIGHT_FOR_SKIP_PROBABILITY = 0.6f;
+ static const float NEAREST_DISTANCE_WEIGHT = 0.5f;
+ static const float NEAREST_DISTANCE_BIAS = 0.5f;
+ static const float NEAREST_DISTANCE_WEIGHT_FOR_LAST = 0.6f;
+ static const float NEAREST_DISTANCE_BIAS_FOR_LAST = 0.4f;
+
+ static const float ANGLE_WEIGHT = 0.90f;
+ static const float DEEP_CORNER_ANGLE_THRESHOLD = M_PI_F * 60.0f / 180.0f;
+ static const float SKIP_DEEP_CORNER_PROBABILITY = 0.1f;
+ static const float CORNER_ANGLE_THRESHOLD = M_PI_F * 30.0f / 180.0f;
+ static const float STRAIGHT_ANGLE_THRESHOLD = M_PI_F * 15.0f / 180.0f;
+ static const float SKIP_CORNER_PROBABILITY = 0.4f;
+ static const float SPEED_MARGIN = 0.1f;
+ static const float CENTER_VALUE_OF_NORMALIZED_DISTRIBUTION = 0.0f;
+
+ const int keyCount = mProximityInfo->getKeyCount();
+ mCharProbabilities.resize(mInputSize);
+ // Calculates probabilities of using a point as a correlated point with the character
+ // for each point.
+ for (int i = start; i < mInputSize; ++i) {
+ mCharProbabilities[i].clear();
+ // First, calculates skip probability. Starts form MIN_SKIP_PROBABILITY.
+ // Note that all values that are multiplied to this probability should be in [0.0, 1.0];
+ float skipProbability = MAX_SKIP_PROBABILITY;
+
+ const float currentAngle = getPointAngle(i);
+ const float relativeSpeed = getRelativeSpeed(i);
+
+ float nearestKeyDistance = static_cast<float>(MAX_POINT_TO_KEY_LENGTH);
+ for (int j = 0; j < keyCount; ++j) {
+ if (mNearKeysVector[i].test(j)) {
+ const float distance = getPointToKeyByIdLength(i, j);
+ if (distance < nearestKeyDistance) {
+ nearestKeyDistance = distance;
+ }
+ }
+ }
+
+ if (i == 0) {
+ skipProbability *= min(1.0f, nearestKeyDistance * NEAREST_DISTANCE_WEIGHT
+ + NEAREST_DISTANCE_BIAS);
+ // Promote the first point
+ skipProbability *= SKIP_FIRST_POINT_PROBABILITY;
+ } else if (i == mInputSize - 1) {
+ skipProbability *= min(1.0f, nearestKeyDistance * NEAREST_DISTANCE_WEIGHT_FOR_LAST
+ + NEAREST_DISTANCE_BIAS_FOR_LAST);
+ // Promote the last point
+ skipProbability *= SKIP_LAST_POINT_PROBABILITY;
+ } else {
+ // If the current speed is relatively slower than adjacent keys, we promote this point.
+ if (getRelativeSpeed(i - 1) - SPEED_MARGIN > relativeSpeed
+ && relativeSpeed < getRelativeSpeed(i + 1) - SPEED_MARGIN) {
+ if (currentAngle < CORNER_ANGLE_THRESHOLD) {
+ skipProbability *= min(1.0f, relativeSpeed
+ * SLOW_STRAIGHT_WEIGHT_FOR_SKIP_PROBABILITY);
+ } else {
+ // If the angle is small enough, we promote this point more. (e.g. pit vs put)
+ skipProbability *= min(1.0f, relativeSpeed * SPEED_WEIGHT_FOR_SKIP_PROBABILITY
+ + MIN_SPEED_RATE_FOR_SKIP_PROBABILITY);
+ }
+ }
+
+ skipProbability *= min(1.0f, relativeSpeed * nearestKeyDistance *
+ NEAREST_DISTANCE_WEIGHT + NEAREST_DISTANCE_BIAS);
+
+ // Adjusts skip probability by a rate depending on angle.
+ // ANGLE_RATE of skipProbability is adjusted by current angle.
+ skipProbability *= (M_PI_F - currentAngle) / M_PI_F * ANGLE_WEIGHT
+ + (1.0f - ANGLE_WEIGHT);
+ if (currentAngle > DEEP_CORNER_ANGLE_THRESHOLD) {
+ skipProbability *= SKIP_DEEP_CORNER_PROBABILITY;
+ }
+ // We assume the angle of this point is the angle for point[i], point[i - 2]
+ // and point[i - 3]. The reason why we don't use the angle for point[i], point[i - 1]
+ // and point[i - 2] is this angle can be more affected by the noise.
+ const float prevAngle = getPointsAngle(i, i - 2, i - 3);
+ if (i >= 3 && prevAngle < STRAIGHT_ANGLE_THRESHOLD
+ && currentAngle > CORNER_ANGLE_THRESHOLD) {
+ skipProbability *= SKIP_CORNER_PROBABILITY;
+ }
+ }
+
+ // probabilities must be in [0.0, MAX_SKIP_PROBABILITY];
+ ASSERT(skipProbability >= 0.0f);
+ ASSERT(skipProbability <= MAX_SKIP_PROBABILITY);
+ mCharProbabilities[i][NOT_AN_INDEX] = skipProbability;
+
+ // Second, calculates key probabilities by dividing the rest probability
+ // (1.0f - skipProbability).
+ const float inputCharProbability = 1.0f - skipProbability;
+
+ // TODO: The variance is critical for accuracy; thus, adjusting these parameter by machine
+ // learning or something would be efficient.
+ static const float SPEEDxANGLE_WEIGHT_FOR_STANDARD_DIVIATION = 0.3f;
+ static const float MAX_SPEEDxANGLE_RATE_FOR_STANDERD_DIVIATION = 0.25f;
+ static const float SPEEDxNEAREST_WEIGHT_FOR_STANDARD_DIVIATION = 0.5f;
+ static const float MAX_SPEEDxNEAREST_RATE_FOR_STANDERD_DIVIATION = 0.15f;
+ static const float MIN_STANDERD_DIVIATION = 0.37f;
+
+ const float speedxAngleRate = min(relativeSpeed * currentAngle / M_PI_F
+ * SPEEDxANGLE_WEIGHT_FOR_STANDARD_DIVIATION,
+ MAX_SPEEDxANGLE_RATE_FOR_STANDERD_DIVIATION);
+ const float speedxNearestKeyDistanceRate = min(relativeSpeed * nearestKeyDistance
+ * SPEEDxNEAREST_WEIGHT_FOR_STANDARD_DIVIATION,
+ MAX_SPEEDxNEAREST_RATE_FOR_STANDERD_DIVIATION);
+ const float sigma = speedxAngleRate + speedxNearestKeyDistanceRate + MIN_STANDERD_DIVIATION;
+
+ NormalDistribution distribution(CENTER_VALUE_OF_NORMALIZED_DISTRIBUTION, sigma);
+ static const float PREV_DISTANCE_WEIGHT = 0.5f;
+ static const float NEXT_DISTANCE_WEIGHT = 0.6f;
+ // Summing up probability densities of all near keys.
+ float sumOfProbabilityDensities = 0.0f;
+ for (int j = 0; j < keyCount; ++j) {
+ if (mNearKeysVector[i].test(j)) {
+ float distance = sqrtf(getPointToKeyByIdLength(i, j));
+ if (i == 0 && i != mInputSize - 1) {
+ // For the first point, weighted average of distances from first point and the
+ // next point to the key is used as a point to key distance.
+ const float nextDistance = sqrtf(getPointToKeyByIdLength(i + 1, j));
+ if (nextDistance < distance) {
+ // The distance of the first point tends to bigger than continuing
+ // points because the first touch by the user can be sloppy.
+ // So we promote the first point if the distance of that point is larger
+ // than the distance of the next point.
+ distance = (distance + nextDistance * NEXT_DISTANCE_WEIGHT)
+ / (1.0f + NEXT_DISTANCE_WEIGHT);
+ }
+ } else if (i != 0 && i == mInputSize - 1) {
+ // For the first point, weighted average of distances from last point and
+ // the previous point to the key is used as a point to key distance.
+ const float previousDistance = sqrtf(getPointToKeyByIdLength(i - 1, j));
+ if (previousDistance < distance) {
+ // The distance of the last point tends to bigger than continuing points
+ // because the last touch by the user can be sloppy. So we promote the
+ // last point if the distance of that point is larger than the distance of
+ // the previous point.
+ distance = (distance + previousDistance * PREV_DISTANCE_WEIGHT)
+ / (1.0f + PREV_DISTANCE_WEIGHT);
+ }
+ }
+ // TODO: Promote the first point when the extended line from the next input is near
+ // from a key. Also, promote the last point as well.
+ sumOfProbabilityDensities += distribution.getProbabilityDensity(distance);
+ }
+ }
+
+ // Split the probability of an input point to keys that are close to the input point.
+ for (int j = 0; j < keyCount; ++j) {
+ if (mNearKeysVector[i].test(j)) {
+ float distance = sqrtf(getPointToKeyByIdLength(i, j));
+ if (i == 0 && i != mInputSize - 1) {
+ // For the first point, weighted average of distances from the first point and
+ // the next point to the key is used as a point to key distance.
+ const float prevDistance = sqrtf(getPointToKeyByIdLength(i + 1, j));
+ if (prevDistance < distance) {
+ distance = (distance + prevDistance * NEXT_DISTANCE_WEIGHT)
+ / (1.0f + NEXT_DISTANCE_WEIGHT);
+ }
+ } else if (i != 0 && i == mInputSize - 1) {
+ // For the first point, weighted average of distances from last point and
+ // the previous point to the key is used as a point to key distance.
+ const float prevDistance = sqrtf(getPointToKeyByIdLength(i - 1, j));
+ if (prevDistance < distance) {
+ distance = (distance + prevDistance * PREV_DISTANCE_WEIGHT)
+ / (1.0f + PREV_DISTANCE_WEIGHT);
+ }
+ }
+ const float probabilityDensity = distribution.getProbabilityDensity(distance);
+ const float probability = inputCharProbability * probabilityDensity
+ / sumOfProbabilityDensities;
+ mCharProbabilities[i][j] = probability;
+ }
+ }
+ }
+
+
+ if (DEBUG_POINTS_PROBABILITY) {
+ for (int i = 0; i < mInputSize; ++i) {
+ std::stringstream sstream;
+ sstream << i << ", ";
+ sstream << "("<< mInputXs[i] << ", ";
+ sstream << ", "<< mInputYs[i] << "), ";
+ sstream << "Speed: "<< getRelativeSpeed(i) << ", ";
+ sstream << "Angle: "<< getPointAngle(i) << ", \n";
+
+ for (hash_map_compat<int, float>::iterator it = mCharProbabilities[i].begin();
+ it != mCharProbabilities[i].end(); ++it) {
+ if (it->first == NOT_AN_INDEX) {
+ sstream << it->first
+ << "(skip):"
+ << it->second
+ << "\n";
+ } else {
+ sstream << it->first
+ << "("
+ << static_cast<char>(mProximityInfo->getCodePointOf(it->first))
+ << "):"
+ << it->second
+ << "\n";
+ }
+ }
+ AKLOGI("%s", sstream.str().c_str());
+ }
+ }
+
+ // Decrease key probabilities of points which don't have the highest probability of that key
+ // among nearby points. Probabilities of the first point and the last point are not suppressed.
+ for (int i = max(start, 1); i < mInputSize; ++i) {
+ for (int j = i + 1; j < mInputSize; ++j) {
+ if (!suppressCharProbabilities(i, j)) {
+ break;
+ }
+ }
+ for (int j = i - 1; j >= max(start, 0); --j) {
+ if (!suppressCharProbabilities(i, j)) {
+ break;
+ }
+ }
+ }
+
+ // Converting from raw probabilities to log probabilities to calculate spatial distance.
+ for (int i = start; i < mInputSize; ++i) {
+ for (int j = 0; j < keyCount; ++j) {
+ hash_map_compat<int, float>::iterator it = mCharProbabilities[i].find(j);
+ if (it == mCharProbabilities[i].end()){
+ mNearKeysVector[i].reset(j);
+ } else if(it->second < MIN_PROBABILITY) {
+ // Erases from near keys vector because it has very low probability.
+ mNearKeysVector[i].reset(j);
+ mCharProbabilities[i].erase(j);
+ } else {
+ it->second = -logf(it->second);
+ }
+ }
+ mCharProbabilities[i][NOT_AN_INDEX] = -logf(mCharProbabilities[i][NOT_AN_INDEX]);
+ }
+}
+
+// Decreases char probabilities of index0 by checking probabilities of a near point (index1) and
+// increases char probabilities of index1 by checking probabilities of index0.
+bool ProximityInfoState::suppressCharProbabilities(const int index0, const int index1) {
+ ASSERT(0 <= index0 && index0 < mInputSize);
+ ASSERT(0 <= index1 && index1 < mInputSize);
+
+ static const float SUPPRESSION_LENGTH_WEIGHT = 1.5f;
+ static const float MIN_SUPPRESSION_RATE = 0.1f;
+ static const float SUPPRESSION_WEIGHT = 0.5f;
+ static const float SUPPRESSION_WEIGHT_FOR_PROBABILITY_GAIN = 0.1f;
+ static const float SKIP_PROBABALITY_WEIGHT_FOR_PROBABILITY_GAIN = 0.3f;
+
+ const float keyWidthFloat = static_cast<float>(mProximityInfo->getMostCommonKeyWidth());
+ const float diff = fabsf(static_cast<float>(mLengthCache[index0] - mLengthCache[index1]));
+ if (diff > keyWidthFloat * SUPPRESSION_LENGTH_WEIGHT) {
+ return false;
+ }
+ const float suppressionRate = MIN_SUPPRESSION_RATE
+ + diff / keyWidthFloat / SUPPRESSION_LENGTH_WEIGHT * SUPPRESSION_WEIGHT;
+ for (hash_map_compat<int, float>::iterator it = mCharProbabilities[index0].begin();
+ it != mCharProbabilities[index0].end(); ++it) {
+ hash_map_compat<int, float>::iterator it2 = mCharProbabilities[index1].find(it->first);
+ if (it2 != mCharProbabilities[index1].end() && it->second < it2->second) {
+ const float newProbability = it->second * suppressionRate;
+ const float suppression = it->second - newProbability;
+ it->second = newProbability;
+ // mCharProbabilities[index0][NOT_AN_INDEX] is the probability of skipping this point.
+ mCharProbabilities[index0][NOT_AN_INDEX] += suppression;
+
+ // Add the probability of the same key nearby index1
+ const float probabilityGain = min(suppression * SUPPRESSION_WEIGHT_FOR_PROBABILITY_GAIN,
+ mCharProbabilities[index1][NOT_AN_INDEX]
+ * SKIP_PROBABALITY_WEIGHT_FOR_PROBABILITY_GAIN);
+ it2->second += probabilityGain;
+ mCharProbabilities[index1][NOT_AN_INDEX] -= probabilityGain;
+ }
+ }
+ return true;
+}
+
+// Get a word that is detected by tracing highest probability sequence into codePointBuf and
+// returns probability of generating the word.
+float ProximityInfoState::getHighestProbabilitySequence(int *const codePointBuf) const {
+ static const float DEMOTION_LOG_PROBABILITY = 0.3f;
+ int index = 0;
+ float sumLogProbability = 0.0f;
+ // TODO: Current implementation is greedy algorithm. DP would be efficient for many cases.
+ for (int i = 0; i < mInputSize && index < MAX_WORD_LENGTH_INTERNAL - 1; ++i) {
+ float minLogProbability = static_cast<float>(MAX_POINT_TO_KEY_LENGTH);
+ int character = NOT_AN_INDEX;
+ for (hash_map_compat<int, float>::const_iterator it = mCharProbabilities[i].begin();
+ it != mCharProbabilities[i].end(); ++it) {
+ const float logProbability = (it->first != NOT_AN_INDEX)
+ ? it->second + DEMOTION_LOG_PROBABILITY : it->second;
+ if (logProbability < minLogProbability) {
+ minLogProbability = logProbability;
+ character = it->first;
+ }
+ }
+ if (character != NOT_AN_INDEX) {
+ codePointBuf[index] = mProximityInfo->getCodePointOf(character);
+ index++;
+ }
+ sumLogProbability += minLogProbability;
+ }
+ codePointBuf[index] = '\0';
+ return sumLogProbability;
+}
+
+// Returns a probability of mapping index to keyIndex.
+float ProximityInfoState::getProbability(const int index, const int keyIndex) const {
+ ASSERT(0 <= index && index < mInputSize);
+ hash_map_compat<int, float>::const_iterator it = mCharProbabilities[index].find(keyIndex);
+ if (it != mCharProbabilities[index].end()) {
+ return it->second;
+ }
+ return static_cast<float>(MAX_POINT_TO_KEY_LENGTH);
+}
+
} // namespace latinime