Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 17 | #ifndef LATINIME_GEOMETRY_UTILS_H |
| 18 | #define LATINIME_GEOMETRY_UTILS_H |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 19 | |
| 20 | #include <cmath> |
| 21 | |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 22 | #define DEBUG_DECODER false |
| 23 | |
Ken Wakasa | bcec82d | 2012-08-12 11:10:48 +0900 | [diff] [blame] | 24 | #define M_PI_F 3.14159265f |
Satoshi Kataoka | f4554d8 | 2012-09-12 20:50:21 +0900 | [diff] [blame] | 25 | #define ROUND_FLOAT_10000(f) ((f) < 1000.0f && (f) > 0.001f) \ |
| 26 | ? (floorf((f) * 10000.0f) / 10000.0f) : (f) |
Satoshi Kataoka | f4554d8 | 2012-09-12 20:50:21 +0900 | [diff] [blame] | 27 | #define SQUARE_FLOAT(x) ((x) * (x)) |
| 28 | |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 29 | namespace latinime { |
| 30 | |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 31 | static inline float getSquaredDistanceFloat(float x1, float y1, float x2, float y2) { |
Satoshi Kataoka | f4554d8 | 2012-09-12 20:50:21 +0900 | [diff] [blame] | 32 | const float deltaX = x1 - x2; |
| 33 | const float deltaY = y1 - y2; |
| 34 | return SQUARE_FLOAT(deltaX) + SQUARE_FLOAT(deltaY); |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 35 | } |
| 36 | |
| 37 | static inline float getDistanceFloat(float x1, float y1, float x2, float y2) { |
| 38 | return hypotf(x1 - x2, y1 - y2); |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 39 | } |
| 40 | |
Ken Wakasa | bcec82d | 2012-08-12 11:10:48 +0900 | [diff] [blame] | 41 | static inline int getDistanceInt(int x1, int y1, int x2, int y2) { |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 42 | return static_cast<int>(getDistanceFloat(static_cast<float>(x1), static_cast<float>(y1), |
| 43 | static_cast<float>(x2), static_cast<float>(y2))); |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 44 | } |
| 45 | |
| 46 | static inline float getAngle(int x1, int y1, int x2, int y2) { |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 47 | const int dx = x1 - x2; |
| 48 | const int dy = y1 - y2; |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 49 | if (dx == 0 && dy == 0) return 0; |
| 50 | return atan2f(static_cast<float>(dy), static_cast<float>(dx)); |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 51 | } |
| 52 | |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 53 | static inline float getAngleDiff(float a1, float a2) { |
Satoshi Kataoka | f4554d8 | 2012-09-12 20:50:21 +0900 | [diff] [blame] | 54 | const float deltaA = fabsf(a1 - a2); |
| 55 | const float diff = ROUND_FLOAT_10000(deltaA); |
Ken Wakasa | bcec82d | 2012-08-12 11:10:48 +0900 | [diff] [blame] | 56 | if (diff > M_PI_F) { |
Satoshi Kataoka | f4554d8 | 2012-09-12 20:50:21 +0900 | [diff] [blame] | 57 | const float normalizedDiff = 2.0f * M_PI_F - diff; |
| 58 | return ROUND_FLOAT_10000(normalizedDiff); |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 59 | } |
| 60 | return diff; |
| 61 | } |
| 62 | |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 63 | static inline float pointToLineSegSquaredDistanceFloat( |
Keisuke Kuroyanagi | 41f12ee | 2012-09-19 12:03:47 +0900 | [diff] [blame] | 64 | float x, float y, float x1, float y1, float x2, float y2, bool extend) { |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 65 | const float ray1x = x - x1; |
| 66 | const float ray1y = y - y1; |
| 67 | const float ray2x = x2 - x1; |
| 68 | const float ray2y = y2 - y1; |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 69 | |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 70 | const float dotProduct = ray1x * ray2x + ray1y * ray2y; |
Satoshi Kataoka | f4554d8 | 2012-09-12 20:50:21 +0900 | [diff] [blame] | 71 | const float lineLengthSqr = SQUARE_FLOAT(ray2x) + SQUARE_FLOAT(ray2y); |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 72 | const float projectionLengthSqr = dotProduct / lineLengthSqr; |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 73 | |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 74 | float projectionX; |
| 75 | float projectionY; |
Keisuke Kuroyanagi | 41f12ee | 2012-09-19 12:03:47 +0900 | [diff] [blame] | 76 | if (!extend && projectionLengthSqr < 0.0f) { |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 77 | projectionX = x1; |
| 78 | projectionY = y1; |
Keisuke Kuroyanagi | 41f12ee | 2012-09-19 12:03:47 +0900 | [diff] [blame] | 79 | } else if (!extend && projectionLengthSqr > 1.0f) { |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 80 | projectionX = x2; |
| 81 | projectionY = y2; |
| 82 | } else { |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 83 | projectionX = x1 + projectionLengthSqr * ray2x; |
| 84 | projectionY = y1 + projectionLengthSqr * ray2y; |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 85 | } |
Ken Wakasa | 0fb9508 | 2012-08-13 17:31:46 +0900 | [diff] [blame] | 86 | return getSquaredDistanceFloat(x, y, projectionX, projectionY); |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 87 | } |
Keisuke Kuroyanagi | 806eba4 | 2012-10-09 19:57:08 +0900 | [diff] [blame^] | 88 | |
| 89 | // Normal distribution N(u, sigma^2). |
| 90 | struct NormalDistribution { |
| 91 | NormalDistribution(const float u, const float sigma) |
| 92 | : mU(u), mSigma(sigma), |
| 93 | mPreComputedNonExpPart(1.0f / sqrtf(2.0f * M_PI_F * sigma * sigma)), |
| 94 | mPreComputedExponentPart(-1.0f / (2.0f * sigma * sigma)) {} |
| 95 | |
| 96 | float getProbabilityDensity(const float x) { |
| 97 | const float shiftedX = x - mU; |
| 98 | return mPreComputedNonExpPart * expf(mPreComputedExponentPart * SQUARE_FLOAT(shiftedX)); |
| 99 | } |
| 100 | private: |
| 101 | DISALLOW_IMPLICIT_CONSTRUCTORS(NormalDistribution); |
| 102 | float mU; // mean value |
| 103 | float mSigma; // standard deviation |
| 104 | float mPreComputedNonExpPart; // = 1 / sqrt(2 * PI * sigma^2) |
| 105 | float mPreComputedExponentPart; // = -1 / (2 * sigma^2) |
| 106 | }; |
Satoshi Kataoka | 6b4a1d7 | 2012-08-10 15:42:56 +0900 | [diff] [blame] | 107 | } // namespace latinime |
Ken Wakasa | 507113a | 2012-08-13 11:36:41 +0900 | [diff] [blame] | 108 | #endif // LATINIME_GEOMETRY_UTILS_H |