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/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef LATINIME_PROXIMITY_INFO_UTILS_H
#define LATINIME_PROXIMITY_INFO_UTILS_H
#include <cmath>
#include "additional_proximity_chars.h"
#include "char_utils.h"
#include "defines.h"
#include "geometry_utils.h"
#include "hash_map_compat.h"
namespace latinime {
class ProximityInfoUtils {
public:
static AK_FORCE_INLINE int getKeyIndexOf(const int keyCount, const int c,
const hash_map_compat<int, int> *const codeToKeyMap) {
if (keyCount == 0) {
// We do not have the coordinate data
return NOT_AN_INDEX;
}
if (c == NOT_A_CODE_POINT) {
return NOT_AN_INDEX;
}
const int lowerCode = toLowerCase(c);
hash_map_compat<int, int>::const_iterator mapPos = codeToKeyMap->find(lowerCode);
if (mapPos != codeToKeyMap->end()) {
return mapPos->second;
}
return NOT_AN_INDEX;
}
static AK_FORCE_INLINE void initializeProximities(const int *const inputCodes,
const int *const inputXCoordinates, const int *const inputYCoordinates,
const int inputSize, const int *const keyXCoordinates,
const int *const keyYCoordinates, const int *const keyWidths, const int *keyHeights,
const int *const proximityCharsArray, const int cellHeight, const int cellWidth,
const int gridWidth, const int mostCommonKeyWidth, const int keyCount,
const char *const localeStr,
const hash_map_compat<int, int> *const codeToKeyMap, int *inputProximities) {
// Initialize
// - mInputCodes
// - mNormalizedSquaredDistances
// TODO: Merge
for (int i = 0; i < inputSize; ++i) {
const int primaryKey = inputCodes[i];
const int x = inputXCoordinates[i];
const int y = inputYCoordinates[i];
int *proximities = &inputProximities[i * MAX_PROXIMITY_CHARS_SIZE];
calculateProximities(keyXCoordinates, keyYCoordinates, keyWidths, keyHeights,
proximityCharsArray, cellHeight, cellWidth, gridWidth, mostCommonKeyWidth,
keyCount, x, y, primaryKey, localeStr, codeToKeyMap, proximities);
}
if (DEBUG_PROXIMITY_CHARS) {
for (int i = 0; i < inputSize; ++i) {
AKLOGI("---");
for (int j = 0; j < MAX_PROXIMITY_CHARS_SIZE; ++j) {
int proximityChar =
inputProximities[i * MAX_PROXIMITY_CHARS_SIZE + j];
proximityChar += 0;
AKLOGI("--- (%d)%c", i, proximityChar);
}
}
}
}
static AK_FORCE_INLINE int getStartIndexFromCoordinates(const int x, const int y,
const int cellHeight, const int cellWidth, const int gridWidth) {
return ((y / cellHeight) * gridWidth + (x / cellWidth)) * MAX_PROXIMITY_CHARS_SIZE;
}
static inline float getSquaredDistanceFloat(const float x1, const float y1, const float x2,
const float y2) {
return SQUARE_FLOAT(x1 - x2) + SQUARE_FLOAT(y1 - y2);
}
static inline float pointToLineSegSquaredDistanceFloat(const float x, const float y,
const float x1, const float y1, const float x2, const float y2, const bool extend) {
const float ray1x = x - x1;
const float ray1y = y - y1;
const float ray2x = x2 - x1;
const float ray2y = y2 - y1;
const float dotProduct = ray1x * ray2x + ray1y * ray2y;
const float lineLengthSqr = SQUARE_FLOAT(ray2x) + SQUARE_FLOAT(ray2y);
const float projectionLengthSqr = dotProduct / lineLengthSqr;
float projectionX;
float projectionY;
if (!extend && projectionLengthSqr < 0.0f) {
projectionX = x1;
projectionY = y1;
} else if (!extend && projectionLengthSqr > 1.0f) {
projectionX = x2;
projectionY = y2;
} else {
projectionX = x1 + projectionLengthSqr * ray2x;
projectionY = y1 + projectionLengthSqr * ray2y;
}
return getSquaredDistanceFloat(x, y, projectionX, projectionY);
}
// Normal distribution N(u, sigma^2).
struct NormalDistribution {
public:
NormalDistribution(const float u, const float sigma)
: mU(u), mSigma(sigma),
mPreComputedNonExpPart(1.0f / sqrtf(2.0f * M_PI_F * SQUARE_FLOAT(sigma))),
mPreComputedExponentPart(-1.0f / (2.0f * SQUARE_FLOAT(sigma))) {}
float getProbabilityDensity(const float x) const {
const float shiftedX = x - mU;
return mPreComputedNonExpPart * expf(mPreComputedExponentPart * SQUARE_FLOAT(shiftedX));
}
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(NormalDistribution);
const float mU; // mean value
const float mSigma; // standard deviation
const float mPreComputedNonExpPart; // = 1 / sqrt(2 * PI * sigma^2)
const float mPreComputedExponentPart; // = -1 / (2 * sigma^2)
}; // struct NormalDistribution
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(ProximityInfoUtils);
static bool isOnKey(const int *const keyXCoordinates, const int *const keyYCoordinates,
const int *const keyWidths, const int *keyHeights, const int keyId, const int x,
const int y) {
if (keyId < 0) return true; // NOT_A_ID is -1, but return whenever < 0 just in case
const int left = keyXCoordinates[keyId];
const int top = keyYCoordinates[keyId];
const int right = left + keyWidths[keyId] + 1;
const int bottom = top + keyHeights[keyId];
return left < right && top < bottom && x >= left && x < right && y >= top && y < bottom;
}
static AK_FORCE_INLINE void calculateProximities(const int *const keyXCoordinates,
const int *const keyYCoordinates, const int *const keyWidths, const int *keyHeights,
const int *const proximityCharsArray, const int cellHeight, const int cellWidth,
const int gridWidth, const int mostCommonKeyWidth, const int keyCount,
const int x, const int y, const int primaryKey, const char *const localeStr,
const hash_map_compat<int, int> *const codeToKeyMap, int *proximities) {
const int mostCommonKeyWidthSquare = mostCommonKeyWidth * mostCommonKeyWidth;
int insertPos = 0;
proximities[insertPos++] = primaryKey;
const int startIndex = getStartIndexFromCoordinates(x, y, cellHeight, cellWidth, gridWidth);
if (startIndex >= 0) {
for (int i = 0; i < MAX_PROXIMITY_CHARS_SIZE; ++i) {
const int c = proximityCharsArray[startIndex + i];
if (c < KEYCODE_SPACE || c == primaryKey) {
continue;
}
const int keyIndex = getKeyIndexOf(keyCount, c, codeToKeyMap);
const bool onKey = isOnKey(keyXCoordinates, keyYCoordinates, keyWidths, keyHeights,
keyIndex, x, y);
const int distance = squaredLengthToEdge(keyXCoordinates, keyYCoordinates,
keyWidths, keyHeights, keyIndex, x, y);
if (onKey || distance < mostCommonKeyWidthSquare) {
proximities[insertPos++] = c;
if (insertPos >= MAX_PROXIMITY_CHARS_SIZE) {
if (DEBUG_DICT) {
ASSERT(false);
}
return;
}
}
}
const int additionalProximitySize =
AdditionalProximityChars::getAdditionalCharsSize(localeStr, primaryKey);
if (additionalProximitySize > 0) {
proximities[insertPos++] = ADDITIONAL_PROXIMITY_CHAR_DELIMITER_CODE;
if (insertPos >= MAX_PROXIMITY_CHARS_SIZE) {
if (DEBUG_DICT) {
ASSERT(false);
}
return;
}
const int *additionalProximityChars =
AdditionalProximityChars::getAdditionalChars(localeStr, primaryKey);
for (int j = 0; j < additionalProximitySize; ++j) {
const int ac = additionalProximityChars[j];
int k = 0;
for (; k < insertPos; ++k) {
if (ac == proximities[k]) {
break;
}
}
if (k < insertPos) {
continue;
}
proximities[insertPos++] = ac;
if (insertPos >= MAX_PROXIMITY_CHARS_SIZE) {
if (DEBUG_DICT) {
ASSERT(false);
}
return;
}
}
}
}
// Add a delimiter for the proximity characters
for (int i = insertPos; i < MAX_PROXIMITY_CHARS_SIZE; ++i) {
proximities[i] = NOT_A_CODE_POINT;
}
}
static int squaredLengthToEdge(const int *const keyXCoordinates,
const int *const keyYCoordinates, const int *const keyWidths, const int *keyHeights,
const int keyId, const int x, const int y) {
// NOT_A_ID is -1, but return whenever < 0 just in case
if (keyId < 0) return MAX_VALUE_FOR_WEIGHTING;
const int left = keyXCoordinates[keyId];
const int top = keyYCoordinates[keyId];
const int right = left + keyWidths[keyId];
const int bottom = top + keyHeights[keyId];
const int edgeX = x < left ? left : (x > right ? right : x);
const int edgeY = y < top ? top : (y > bottom ? bottom : y);
const int dx = x - edgeX;
const int dy = y - edgeY;
return dx * dx + dy * dy;
}
};
} // namespace latinime
#endif // LATINIME_PROXIMITY_INFO_UTILS_H