Refactor most probable string

Change-Id: I96597decf5e36d9ce088c34427915f2379255054

native/jni/src/proximity_info_state.cpp

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-#include <cstring> // for memset()
+#include <cstring> // for memset() and memcpy()
 #include <sstream> // for debug prints
 
 #define LOG_TAG "LatinIME: proximity_info_state.cpp"
@@ -59,12 +59,15 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
     int pushTouchPointStartIndex = 0;
     int lastSavedInputSize = 0;
     mMaxPointToKeyLength = maxPointToKeyLength;
+    mSampledInputSize = 0;
+    mMostProbableStringProbability = 0.0f;
+
     if (mIsContinuationPossible && mSampledInputIndice.size() > 1) {
         // Just update difference.
-        // Two points prior is never skipped. Thus, we pop 2 input point data here.
+        // Previous two points are never skipped. Thus, we pop 2 input point data here.
-        pushTouchPointStartIndex = mSampledInputIndice[mSampledInputIndice.size() - 2];
+        pushTouchPointStartIndex = ProximityInfoStateUtils::trimLastTwoTouchPoints(
-        popInputData();
+                &mSampledInputXs, &mSampledInputYs, &mSampledTimes, &mSampledLengthCache,
-        popInputData();
+                &mSampledInputIndice);
         lastSavedInputSize = mSampledInputXs.size();
     } else {
         // Clear all data.
@@ -81,11 +84,11 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
         mCharProbabilities.clear();
         mDirections.clear();
     }
+
     if (DEBUG_GEO_FULL) {
         AKLOGI("Init ProximityInfoState: reused points =  %d, last input size = %d",
                 pushTouchPointStartIndex, lastSavedInputSize);
     }
-    mSampledInputSize = 0;
 
     if (xCoordinates && yCoordinates) {
         mSampledInputSize = ProximityInfoStateUtils::updateTouchPoints(
@@ -121,6 +124,9 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
             ProximityInfoStateUtils::updateSampledSearchKeysVector(mProximityInfo,
                     mSampledInputSize, lastSavedInputSize, &mSampledLengthCache,
                     &mSampledNearKeysVector, &mSampledSearchKeysVector);
+            mMostProbableStringProbability = ProximityInfoStateUtils::getMostProbableString(
+                    mProximityInfo, mSampledInputSize, &mCharProbabilities, mMostProbableString);
+
         }
     }
 
@@ -132,8 +138,6 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
     // end
     ///////////////////////
 
-    memset(mNormalizedSquaredDistances, NOT_A_DISTANCE, sizeof(mNormalizedSquaredDistances));
-    memset(mPrimaryInputWord, 0, sizeof(mPrimaryInputWord));
     mTouchPositionCorrectionEnabled = mSampledInputSize > 0 && mHasTouchPositionCorrectionData
             && xCoordinates && yCoordinates;
     if (!isGeometric && pointerId == 0) {
@@ -142,8 +146,7 @@ void ProximityInfoState::initInputParams(const int pointerId, const float maxPoi
         if (mTouchPositionCorrectionEnabled) {
             ProximityInfoStateUtils::initNormalizedSquaredDistances(
                     mProximityInfo, inputSize, xCoordinates, yCoordinates, mInputProximities,
-                    hasInputCoordinates(), &mSampledInputXs, &mSampledInputYs,
+                    &mSampledInputXs, &mSampledInputYs, mNormalizedSquaredDistances);
-                    mNormalizedSquaredDistances);
         }
     }
     if (DEBUG_GEO_FULL) {
@@ -278,16 +281,10 @@ int ProximityInfoState::getAllPossibleChars(
 }
 
 bool ProximityInfoState::isKeyInSerchKeysAfterIndex(const int index, const int keyId) const {
-    ASSERT(keyId >= 0);
+    ASSERT(keyId >= 0 && index >= 0 && index < mSampledInputSize);
-    ASSERT(index >= 0 && index < mSampledInputSize);
     return mSampledSearchKeysVector[index].test(keyId);
 }
 
-void ProximityInfoState::popInputData() {
-    ProximityInfoStateUtils::popInputData(&mSampledInputXs, &mSampledInputYs, &mSampledTimes,
-            &mSampledLengthCache, &mSampledInputIndice);
-}
-
 float ProximityInfoState::getDirection(const int index0, const int index1) const {
     return ProximityInfoStateUtils::getDirection(
             &mSampledInputXs, &mSampledInputYs, index0, index1);
@@ -313,33 +310,9 @@ float ProximityInfoState::getLineToKeyDistance(
             keyX, keyY, x0, y0, x1, y1, extend);
 }
 
-// Get a word that is detected by tracing the most probable string into codePointBuf and
-// returns probability of generating the word.
 float ProximityInfoState::getMostProbableString(int *const codePointBuf) const {
-    static const float DEMOTION_LOG_PROBABILITY = 0.3f;
+    memcpy(codePointBuf, mMostProbableString, sizeof(mMostProbableString));
-    int index = 0;
+    return mMostProbableStringProbability;
-    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 - 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;
 }
 
 bool ProximityInfoState::hasSpaceProximity(const int index) const {

native/jni/src/proximity_info_state.h

@@ -54,10 +54,12 @@ class ProximityInfoState {
               mSampledInputIndice(), mSampledLengthCache(), mBeelineSpeedPercentiles(),
               mSampledDistanceCache_G(), mSpeedRates(), mDirections(), mCharProbabilities(),
               mSampledNearKeysVector(), mSampledSearchKeysVector(),
-              mTouchPositionCorrectionEnabled(false), mSampledInputSize(0) {
+              mTouchPositionCorrectionEnabled(false), mSampledInputSize(0),
+              mMostProbableStringProbability(0.0f) {
         memset(mInputProximities, 0, sizeof(mInputProximities));
         memset(mNormalizedSquaredDistances, 0, sizeof(mNormalizedSquaredDistances));
         memset(mPrimaryInputWord, 0, sizeof(mPrimaryInputWord));
+        memset(mMostProbableString, 0, sizeof(mMostProbableString));
     }
 
     // Non virtual inline destructor -- never inherit this class
@@ -67,6 +69,21 @@ class ProximityInfoState {
         return getProximityCodePointsAt(index)[0];
     }
 
+    inline bool sameAsTyped(const int *word, int length) const {
+        if (length != mSampledInputSize) {
+            return false;
+        }
+        const int *inputProximities = mInputProximities;
+        while (length--) {
+            if (*inputProximities != *word) {
+                return false;
+            }
+            inputProximities += MAX_PROXIMITY_CHARS_SIZE;
+            word++;
+        }
+        return true;
+    }
+
     AK_FORCE_INLINE bool existsCodePointInProximityAt(const int index, const int c) const {
         const int *codePoints = getProximityCodePointsAt(index);
         int i = 0;
@@ -107,21 +124,6 @@ class ProximityInfoState {
         return mTouchPositionCorrectionEnabled;
     }
 
-    inline bool sameAsTyped(const int *word, int length) const {
-        if (length != mSampledInputSize) {
-            return false;
-        }
-        const int *inputProximities = mInputProximities;
-        while (length--) {
-            if (*inputProximities != *word) {
-                return false;
-            }
-            inputProximities += MAX_PROXIMITY_CHARS_SIZE;
-            word++;
-        }
-        return true;
-    }
-
     bool isUsed() const {
         return mSampledInputSize > 0;
     }
@@ -208,14 +210,9 @@ class ProximityInfoState {
     // Defined here                        //
     /////////////////////////////////////////
 
-    bool hasInputCoordinates() const {
-        return mSampledInputXs.size() > 0 && mSampledInputYs.size() > 0;
-    }
-
     inline const int *getProximityCodePointsAt(const int index) const {
         return ProximityInfoStateUtils::getProximityCodePointsAt(mInputProximities, index);
     }
-    void popInputData();
 
     // const
     const ProximityInfo *mProximityInfo;
@@ -255,6 +252,8 @@ class ProximityInfoState {
     int mNormalizedSquaredDistances[MAX_PROXIMITY_CHARS_SIZE * MAX_WORD_LENGTH];
     int mSampledInputSize;
     int mPrimaryInputWord[MAX_WORD_LENGTH];
+    float mMostProbableStringProbability;
+    int mMostProbableString[MAX_WORD_LENGTH];
 };
 } // namespace latinime
 #endif // LATINIME_PROXIMITY_INFO_STATE_H

native/jni/src/proximity_info_state_utils.cpp

@@ -15,6 +15,7 @@
  */
 
 #include <cmath>
+#include <cstring> // for memset()
 #include <sstream> // for debug prints
 #include <vector>
 
@@ -26,6 +27,17 @@
 
 namespace latinime {
 
+/* static */ int ProximityInfoStateUtils::trimLastTwoTouchPoints(std::vector<int> *sampledInputXs,
+        std::vector<int> *sampledInputYs, std::vector<int> *sampledInputTimes,
+        std::vector<int> *sampledLengthCache, std::vector<int> *sampledInputIndice) {
+    const int nextStartIndex = (*sampledInputIndice)[sampledInputIndice->size() - 2];
+    popInputData(sampledInputXs, sampledInputYs, sampledInputTimes, sampledLengthCache,
+            sampledInputIndice);
+    popInputData(sampledInputXs, sampledInputYs, sampledInputTimes, sampledLengthCache,
+            sampledInputIndice);
+    return nextStartIndex;
+}
+
 /* static */ int ProximityInfoStateUtils::updateTouchPoints(const int mostCommonKeyWidth,
         const ProximityInfo *const proximityInfo, const int maxPointToKeyLength,
         const int *const inputProximities, const int *const inputXCoordinates,
@@ -133,6 +145,7 @@ namespace latinime {
 
 /* static */ void ProximityInfoStateUtils::initPrimaryInputWord(
         const int inputSize, const int *const inputProximities, int *primaryInputWord) {
+    memset(primaryInputWord, 0, sizeof(primaryInputWord[0]) * MAX_WORD_LENGTH);
     for (int i = 0; i < inputSize; ++i) {
         primaryInputWord[i] = getPrimaryCodePointAt(inputProximities, i);
     }
@@ -171,10 +184,13 @@ namespace latinime {
 /* static */ void ProximityInfoStateUtils::initNormalizedSquaredDistances(
         const ProximityInfo *const proximityInfo, const int inputSize,
         const int *inputXCoordinates, const int *inputYCoordinates,
-        const int *const inputProximities, const bool hasInputCoordinates,
+        const int *const inputProximities,
         const std::vector<int> *const sampledInputXs,
         const std::vector<int> *const sampledInputYs,
         int *normalizedSquaredDistances) {
+    memset(normalizedSquaredDistances, NOT_A_DISTANCE,
+            sizeof(normalizedSquaredDistances[0]) * MAX_PROXIMITY_CHARS_SIZE * MAX_WORD_LENGTH);
+    const bool hasInputCoordinates = sampledInputXs->size() > 0 && sampledInputYs->size() > 0;
     for (int i = 0; i < inputSize; ++i) {
         const int *proximityCodePoints = getProximityCodePointsAt(inputProximities, i);
         const int primaryKey = proximityCodePoints[0];
@@ -1011,6 +1027,40 @@ namespace latinime {
     return true;
 }
 
+// Get a word that is detected by tracing the most probable string into codePointBuf and
+// returns probability of generating the word.
+/* static */ float ProximityInfoStateUtils::getMostProbableString(
+        const ProximityInfo *const proximityInfo, const int sampledInputSize,
+        const std::vector<hash_map_compat<int, float> > *const charProbabilities,
+        int *const codePointBuf) {
+    ASSERT(charProbabilities->size() >= 0 && sampledInputSize >= 0);
+    memset(codePointBuf, 0, sizeof(codePointBuf[0]) * MAX_WORD_LENGTH);
+    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 < sampledInputSize && index < MAX_WORD_LENGTH - 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 = (*charProbabilities)[i].begin();
+                it != (*charProbabilities)[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] = proximityInfo->getCodePointOf(character);
+            index++;
+        }
+        sumLogProbability += minLogProbability;
+    }
+    codePointBuf[index] = '\0';
+    return sumLogProbability;
+}
+
 /* static */ void ProximityInfoStateUtils::dump(const bool isGeometric, const int inputSize,
         const int *const inputXCoordinates, const int *const inputYCoordinates,
         const int sampledInputSize, const std::vector<int> *const sampledInputXs,

native/jni/src/proximity_info_state_utils.h

@@ -32,6 +32,9 @@ class ProximityInfoStateUtils {
     typedef hash_map_compat<int, float> NearKeysDistanceMap;
     typedef std::bitset<MAX_KEY_COUNT_IN_A_KEYBOARD> NearKeycodesSet;
 
+    static int trimLastTwoTouchPoints(std::vector<int> *sampledInputXs,
+            std::vector<int> *sampledInputYs, std::vector<int> *sampledInputTimes,
+            std::vector<int> *sampledLengthCache, std::vector<int> *sampledInputIndice);
     static int updateTouchPoints(const int mostCommonKeyWidth,
             const ProximityInfo *const proximityInfo, const int maxPointToKeyLength,
             const int *const inputProximities,
@@ -96,7 +99,7 @@ class ProximityInfoStateUtils {
     static void initNormalizedSquaredDistances(
             const ProximityInfo *const proximityInfo, const int inputSize,
             const int *inputXCoordinates, const int *inputYCoordinates,
-            const int *const inputProximities, const bool hasInputCoordinates,
+            const int *const inputProximities,
             const std::vector<int> *const sampledInputXs,
             const std::vector<int> *const sampledInputYs,
             int *normalizedSquaredDistances);
@@ -113,6 +116,12 @@ class ProximityInfoStateUtils {
             const std::vector<int> *const sampledInputYs,
             const std::vector<int> *const sampledTimes,
             const std::vector<int> *const sampledInputIndices);
+    // TODO: Move to most_probable_string_utils.h
+    static float getMostProbableString(
+            const ProximityInfo *const proximityInfo, const int sampledInputSize,
+            const std::vector<hash_map_compat<int, float> > *const charProbabilities,
+            int *const codePointBuf);
+
  private:
     DISALLOW_IMPLICIT_CONSTRUCTORS(ProximityInfoStateUtils);