diff options
Diffstat (limited to 'native/jni/src/proximity_info_state.cpp')
| -rw-r--r-- | native/jni/src/proximity_info_state.cpp | 840 |
1 files changed, 671 insertions, 169 deletions
diff --git a/native/jni/src/proximity_info_state.cpp b/native/jni/src/proximity_info_state.cpp index 392ec8194..e64d46d01 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]; @@ -94,23 +95,26 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi pushTouchPointStartIndex = mInputIndice[mInputIndice.size() - 2]; popInputData(); popInputData(); - lastSavedInputSize = mInputXs.size(); + lastSavedInputSize = mSampledInputXs.size(); } else { // Clear all data. - mInputXs.clear(); - mInputYs.clear(); + mSampledInputXs.clear(); + mSampledInputYs.clear(); mTimes.clear(); mInputIndice.clear(); 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", pushTouchPointStartIndex, lastSavedInputSize); } - mInputSize = 0; + mSampledInputSize = 0; if (xCoordinates && yCoordinates) { const bool proximityOnly = !isGeometric && (xCoordinates[0] < 0 || yCoordinates[0] < 0); @@ -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; @@ -154,97 +171,104 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi prevPrevNearKeysDistances = prevNearKeysDistances; prevNearKeysDistances = currentNearKeysDistances; currentNearKeysDistances = tmp; + sumAngle = 0.0f; } } } - mInputSize = mInputXs.size(); - } - - 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); - 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]; - } else { - length = 0; - duration = 1; - } - const float speed = static_cast<float>(length) / static_cast<float>(duration); - mRelativeSpeeds[i] = speed / averageSpeed; + mSampledInputSize = mSampledInputXs.size(); + } + + if (mSampledInputSize > 0 && isGeometric) { + refreshRelativeSpeed(inputSize, xCoordinates, yCoordinates, times, lastSavedInputSize); + } + + if (DEBUG_GEO_FULL) { + for (int i = 0; i < mSampledInputSize; ++i) { + AKLOGI("Sampled(%d): x = %d, y = %d, time = %d", i, mSampledInputXs[i], + mSampledInputYs[i], mTimes[i]); } } - if (mInputSize > 0) { + if (mSampledInputSize > 0) { const int keyCount = mProximityInfo->getKeyCount(); - mNearKeysVector.resize(mInputSize); - mDistanceCache.resize(mInputSize * keyCount); - for (int i = lastSavedInputSize; i < mInputSize; ++i) { + mNearKeysVector.resize(mSampledInputSize); + mSearchKeysVector.resize(mSampledInputSize); + mDistanceCache.resize(mSampledInputSize * keyCount); + for (int i = lastSavedInputSize; i < mSampledInputSize; ++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; - const int x = mInputXs[i]; - const int y = mInputYs[i]; + const int x = mSampledInputXs[i]; + const int y = mSampledInputYs[i]; const float normalizedSquaredDistance = 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 < mSampledInputSize; ++i) { + if (i >= lastSavedInputSize) { + mSearchKeysVector[i].reset(); + } + for (int j = max(i, lastSavedInputSize); j < mSampledInputSize; ++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 < mSampledInputSize; ++i) { + sampledX << mSampledInputXs[i]; + sampledY << mSampledInputYs[i]; + if (i != mSampledInputSize - 1) { + sampledX << ";"; + sampledY << ";"; + } + } + AKLOGI("original points:\n%s, %s,\nsampled points:\n%s, %s,\n", + originalX.str().c_str(), originalY.str().c_str(), sampledX.str().c_str(), + sampledY.str().c_str()); + } // end /////////////////////// memset(mNormalizedSquaredDistances, NOT_A_DISTANCE, sizeof(mNormalizedSquaredDistances)); memset(mPrimaryInputWord, 0, sizeof(mPrimaryInputWord)); - mTouchPositionCorrectionEnabled = mInputSize > 0 && mHasTouchPositionCorrectionData + mTouchPositionCorrectionEnabled = mSampledInputSize > 0 && mHasTouchPositionCorrectionData && 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]; + for (int i = 0; i < mSampledInputSize && mTouchPositionCorrectionEnabled; ++i) { + 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 +276,12 @@ 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] = @@ -267,23 +292,71 @@ 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); } } } } if (DEBUG_GEO_FULL) { - AKLOGI("ProximityState init finished: %d points out of %d", mInputSize, inputSize); + AKLOGI("ProximityState init finished: %d points out of %d", mSampledInputSize, inputSize); + } +} + +void ProximityInfoState::refreshRelativeSpeed(const int inputSize, const int *const xCoordinates, + const int *const yCoordinates, const int *const times, const int lastSavedInputSize) { + // 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(mSampledInputSize); + for (int i = lastSavedInputSize; i < mSampledInputSize; ++i) { + const int index = mInputIndice[i]; + int length = 0; + int duration = 0; + + // 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 < mSampledInputSize - 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 { + const float speed = static_cast<float>(length) / static_cast<float>(duration); + mRelativeSpeeds[i] = speed / averageSpeed; + } + } + + // Direction calculation. + mDirections.resize(mSampledInputSize - 1); + for (int i = max(0, lastSavedInputSize - 1); i < mSampledInputSize - 1; ++i) { + mDirections[i] = getDirection(i, i + 1); } } bool ProximityInfoState::checkAndReturnIsContinuationPossible(const int inputSize, const int *const xCoordinates, const int *const yCoordinates, const int *const times) { - for (int i = 0; i < mInputSize; ++i) { + for (int i = 0; i < mSampledInputSize; ++i) { const int index = mInputIndice[i]; - if (index > inputSize || xCoordinates[index] != mInputXs[i] || - yCoordinates[index] != mInputYs[i] || times[index] != mTimes[i]) { + if (index > inputSize || xCoordinates[index] != mSampledInputXs[i] || + yCoordinates[index] != mSampledInputYs[i] || times[index] != mTimes[i]) { return false; } } @@ -294,7 +367,7 @@ 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 +405,49 @@ 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 = mSampledInputXs.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; + const int distPrev = getDistanceInt(mSampledInputXs.back(), mSampledInputYs.back(), + mSampledInputXs[size - 2], mSampledInputYs[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 angle1 = getAngle(x, y, mSampledInputXs.back(), mSampledInputYs.back()); + const float angle2 = getAngle(mSampledInputXs.back(), mSampledInputYs.back(), + mSampledInputXs[size - 2], mSampledInputYs[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; @@ -397,64 +455,46 @@ 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(); + size_t size = mSampledInputXs.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. popInputData(); - size = mInputXs.size(); + size = mSampledInputXs.size(); popped = true; } else { 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, mSampledInputXs.back(), mSampledInputYs.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, mSampledInputXs.back(), mSampledInputYs.back(), + getDistanceInt(x, y, mSampledInputXs.back(), mSampledInputYs.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); @@ -464,12 +504,13 @@ bool ProximityInfoState::pushTouchPoint(const int inputIndex, const int nodeChar // Pushing point information. if (size > 0) { mLengthCache.push_back( - mLengthCache.back() + getDistanceInt(x, y, mInputXs.back(), mInputYs.back())); + mLengthCache.back() + getDistanceInt( + x, y, mSampledInputXs.back(), mSampledInputYs.back())); } else { mLengthCache.push_back(0); } - mInputXs.push_back(x); - mInputYs.push_back(y); + mSampledInputXs.push_back(x); + mSampledInputYs.push_back(y); mTimes.push_back(time); mInputIndice.push_back(inputIndex); if (DEBUG_GEO_FULL) { @@ -487,7 +528,7 @@ float ProximityInfoState::calculateNormalizedSquaredDistance( if (!mProximityInfo->hasSweetSpotData(keyIndex)) { return NOT_A_DISTANCE_FLOAT; } - if (NOT_A_COORDINATE == mInputXs[inputIndex]) { + if (NOT_A_COORDINATE == mSampledInputXs[inputIndex]) { return NOT_A_DISTANCE_FLOAT; } const float squaredDistance = calculateSquaredDistanceFromSweetSpotCenter( @@ -497,28 +538,98 @@ float ProximityInfoState::calculateNormalizedSquaredDistance( } int ProximityInfoState::getDuration(const int index) const { - if (index >= 0 && index < mInputSize - 1) { + if (index >= 0 && index < mSampledInputSize - 1) { return mTimes[index + 1] - mTimes[index]; } 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); } @@ -526,20 +637,21 @@ float ProximityInfoState::calculateSquaredDistanceFromSweetSpotCenter( const int keyIndex, const int inputIndex) const { const float sweetSpotCenterX = mProximityInfo->getSweetSpotCenterXAt(keyIndex); const float sweetSpotCenterY = mProximityInfo->getSweetSpotCenterYAt(keyIndex); - const float inputX = static_cast<float>(mInputXs[inputIndex]); - const float inputY = static_cast<float>(mInputYs[inputIndex]); + const float inputX = static_cast<float>(mSampledInputXs[inputIndex]); + const float inputY = static_cast<float>(mSampledInputYs[inputIndex]); return square(inputX - sweetSpotCenterX) + square(inputY - sweetSpotCenterY); } // Puts possible characters into filter and returns new filter size. int32_t ProximityInfoState::getAllPossibleChars( const size_t index, int32_t *const filter, const int32_t filterSize) const { - if (index >= mInputXs.size()) { + if (index >= mSampledInputXs.size()) { 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 @@ -557,12 +669,402 @@ int32_t ProximityInfoState::getAllPossibleChars( return newFilterSize; } +bool ProximityInfoState::isKeyInSerchKeysAfterIndex(const int index, const int keyId) const { + ASSERT(keyId >= 0); + ASSERT(index >= 0 && index < mSampledInputSize); + return mSearchKeysVector[index].test(keyId); +} + void ProximityInfoState::popInputData() { - mInputXs.pop_back(); - mInputYs.pop_back(); + mSampledInputXs.pop_back(); + mSampledInputYs.pop_back(); mTimes.pop_back(); mLengthCache.pop_back(); mInputIndice.pop_back(); } +float ProximityInfoState::getDirection(const int index0, const int index1) const { + if (index0 < 0 || index0 > mSampledInputSize - 1) { + return 0.0f; + } + if (index1 < 0 || index1 > mSampledInputSize - 1) { + return 0.0f; + } + const int x1 = mSampledInputXs[index0]; + const int y1 = mSampledInputYs[index0]; + const int x2 = mSampledInputXs[index1]; + const int y2 = mSampledInputYs[index1]; + return getAngle(x1, y1, x2, y2); +} + +float ProximityInfoState::getPointAngle(const int index) const { + if (index <= 0 || index >= mSampledInputSize - 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 > mSampledInputSize - 1) { + return 0.0f; + } + if (index1 < 0 || index1 > mSampledInputSize - 1) { + return 0.0f; + } + if (index2 < 0 || index2 > mSampledInputSize - 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 > mSampledInputSize - 1) { + return 0.0f; + } + if (to < 0 || to > mSampledInputSize - 1) { + return 0.0f; + } + const int x0 = mSampledInputXs[from]; + const int y0 = mSampledInputYs[from]; + const int x1 = mSampledInputXs[to]; + const int y1 = mSampledInputYs[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(mSampledInputSize); + // Calculates probabilities of using a point as a correlated point with the character + // for each point. + for (int i = start; i < mSampledInputSize; ++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 == mSampledInputSize - 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 != mSampledInputSize - 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 == mSampledInputSize - 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 != mSampledInputSize - 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 == mSampledInputSize - 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 < mSampledInputSize; ++i) { + std::stringstream sstream; + sstream << i << ", "; + sstream << "(" << mSampledInputXs[i] << ", " << mSampledInputYs[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 < mSampledInputSize; ++i) { + for (int j = i + 1; j < mSampledInputSize; ++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 < mSampledInputSize; ++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 < mSampledInputSize); + ASSERT(0 <= index1 && index1 < mSampledInputSize); + + 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 < mSampledInputSize && 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 < mSampledInputSize); + 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 |