2018-06-06 15:47:38 +02:00

131 lines
4.1 KiB
C++

/******************************************************************************
* Spine Runtimes Software License v2.5
*
* Copyright (c) 2013-2016, Esoteric Software
* All rights reserved.
*
* You are granted a perpetual, non-exclusive, non-sublicensable, and
* non-transferable license to use, install, execute, and perform the Spine
* Runtimes software and derivative works solely for personal or internal
* use. Without the written permission of Esoteric Software (see Section 2 of
* the Spine Software License Agreement), you may not (a) modify, translate,
* adapt, or develop new applications using the Spine Runtimes or otherwise
* create derivative works or improvements of the Spine Runtimes or (b) remove,
* delete, alter, or obscure any trademarks or any copyright, trademark, patent,
* or other intellectual property or proprietary rights notices on or in the
* Software, including any copy thereof. Redistributions in binary or source
* form must include this license and terms.
*
* THIS SOFTWARE IS PROVIDED BY ESOTERIC SOFTWARE "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL ESOTERIC SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, BUSINESS INTERRUPTION, OR LOSS OF
* USE, DATA, OR PROFITS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*****************************************************************************/
#ifndef Spine_MathUtil_h
#define Spine_MathUtil_h
#include <spine/SpineObject.h>
#include <float.h>
#include <string.h>
namespace spine {
static const float PI = 3.1415926535897932385f;
static const float PI_2 = PI * 2;
static const float DEG_RAD = (PI / 180.0f);
static const float RAD_DEG = (180.0f / PI);
class MathUtil : public SpineObject {
private:
MathUtil();
public:
template<typename T>
static inline T min(T a, T b) { return a < b ? a : b; }
template<typename T>
static inline T max(T a, T b) { return a > b ? a : b; }
static float sign(float val);
static float clamp(float x, float lower, float upper);
static float abs(float v);
/// Returns the sine in radians from a lookup table.
static float sin(float radians);
/// Returns the cosine in radians from a lookup table.
static float cos(float radians);
/// Returns the sine in radians from a lookup table.
static float sinDeg(float degrees);
/// Returns the cosine in radians from a lookup table.
static float cosDeg(float degrees);
/// Returns atan2 in radians, faster but less accurate than Math.Atan2. Average error of 0.00231 radians (0.1323
/// degrees), largest error of 0.00488 radians (0.2796 degrees).
static float atan2(float y, float x);
static float acos(float v);
static float sqrt(float v);
static float fmod(float a, float b);
static bool isNan(float v);
static float random();
static float randomTriangular(float min, float max);
static float randomTriangular(float min, float max, float mode);
static float pow(float a, float b);
};
struct Interpolation {
virtual float apply(float a) = 0;
virtual float interpolate(float start, float end, float a) {
return start + (end - start) * apply(a);
}
virtual ~Interpolation() {};
};
struct PowInterpolation: public Interpolation {
PowInterpolation(int power): power(power) {
}
float apply(float a) {
if (a <= 0.5f) return MathUtil::pow(a * 2.0f, (float)power) / 2.0f;
return MathUtil::pow((a - 1.0f) * 2.0f, (float)power) / (power % 2 == 0 ? -2.0f : 2.0f) + 1.0f;
}
int power;
};
struct PowOutInterpolation: public Interpolation {
PowOutInterpolation(int power): power(power) {
}
float apply(float a) {
return MathUtil::pow(a - 1, (float)power) * (power % 2 == 0 ? -1.0f : 1.0f) + 1.0f;
}
int power;
};
}
#endif /* Spine_MathUtil_h */