LatinIME/native/jni/src/geometry_utils.h

/*
 * Copyright (C) 2012 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_GEOMETRY_UTILS_H
#define LATINIME_GEOMETRY_UTILS_H

#include <cmath>

#include "defines.h"

#define ROUND_FLOAT_10000(f) ((f) < 1000.0f && (f) > 0.001f) \
        ? (floorf((f) * 10000.0f) / 10000.0f) : (f)

namespace latinime {

static inline float SQUARE_FLOAT(const float x) { return x * x; }

static AK_FORCE_INLINE float getAngle(const int x1, const int y1, const int x2, const int y2) {
    const int dx = x1 - x2;
    const int dy = y1 - y2;
    if (dx == 0 && dy == 0) return 0.0f;
    return atan2f(static_cast<float>(dy), static_cast<float>(dx));
}

static AK_FORCE_INLINE float getAngleDiff(const float a1, const float a2) {
    const float deltaA = fabsf(a1 - a2);
    const float diff = ROUND_FLOAT_10000(deltaA);
    if (diff > M_PI_F) {
        const float normalizedDiff = 2.0f * M_PI_F - diff;
        return ROUND_FLOAT_10000(normalizedDiff);
    }
    return diff;
}

static AK_FORCE_INLINE int getDistanceInt(const int x1, const int y1, const int x2,
        const int y2) {
    return static_cast<int>(hypotf(static_cast<float>(x1 - x2), static_cast<float>(y1 - y2)));
}
} // namespace latinime
#endif // LATINIME_GEOMETRY_UTILS_H