Stephen Gowen d7a569d47d wip
2017-10-22 21:08:29 -04:00

107 lines
3.9 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 <math.h>
#include <float.h>
#define SPINE_PI 3.1415927f
#define SPINE_PI_2 SPINE_PI * 2
#define RadDeg 180.0f / SPINE_PI
#define DegRad SPINE_PI / 180.0f
#define SIN_BITS 14 // 16KB. Adjust for accuracy.
#define SIN_MASK ~(-(1 << SIN_BITS))
#define SIN_COUNT SIN_MASK + 1
#define RadFull SPINE_PI * 2
#define DegFull 360
#define RadToIndex SIN_COUNT / RadFull
#define DegToIndex SIN_COUNT / DegFull
#define MAX(a, b) (((a) > (b)) ? (a) : (b))
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
namespace Spine
{
inline bool areFloatsPracticallyEqual(float A, float B, float maxDiff = 0.0000000000000001f, float maxRelDiff = FLT_EPSILON)
{
// Check if the numbers are really close -- needed
// when comparing numbers near zero.
float diff = fabs(A - B);
if (diff <= maxDiff)
{
return true;
}
A = fabs(A);
B = fabs(B);
float largest = (B > A) ? B : A;
if (diff <= largest * maxRelDiff)
{
return true;
}
return false;
}
class MathUtil
{
public:
static float SIN_TABLE[SIN_COUNT];
MathUtil();
/// 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);
};
inline float clamp(float x, float lower, float upper)
{
return fminf(upper, fmaxf(x, lower));
}
}
#endif /* Spine_MathUtil_h */