mirror of
https://github.com/love2d/love.git
synced 2026-08-12 08:30:56 +02:00
Alex Szpakowski
123 lines
3.4 KiB
C++
123 lines
3.4 KiB
C++
/**
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* Copyright (c) 2006-2013 LOVE Development Team
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*
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* This software is provided 'as-is', without any express or implied
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* warranty. In no event will the authors be held liable for any damages
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* arising from the use of this software.
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*
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* Permission is granted to anyone to use this software for any purpose,
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* including commercial applications, and to alter it and redistribute it
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* freely, subject to the following restrictions:
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*
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* 1. The origin of this software must not be misrepresented; you must not
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* claim that you wrote the original software. If you use this software
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* in a product, an acknowledgment in the product documentation would be
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* appreciated but is not required.
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* 2. Altered source versions must be plainly marked as such, and must not be
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* misrepresented as being the original software.
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* 3. This notice may not be removed or altered from any source distribution.
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**/
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#ifndef LOVE_MATH_H
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#define LOVE_MATH_H
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#include <climits> // for CHAR_BIT
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#include <cstdlib> // for rand() and RAND_MAX
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/* Definitions of useful mathematical constants
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* M_E - e
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* M_LOG2E - log2(e)
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* M_LOG10E - log10(e)
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* M_LN2 - ln(2)
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* M_LN10 - ln(10)
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* M_PI - pi
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* M_PI_2 - pi/2
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* M_PI_4 - pi/4
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* M_1_PI - 1/pi
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* M_2_PI - 2/pi
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* M_2_SQRTPI - 2/sqrt(pi)
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* M_SQRT2 - sqrt(2)
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* M_SQRT1_2 - 1/sqrt(2)
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*/
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#define LOVE_M_E 2.71828182845904523536
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#define LOVE_M_LOG2E 1.44269504088896340736
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#define LOVE_M_LOG10E 0.434294481903251827651
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#define LOVE_M_LN2 0.693147180559945309417
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#define LOVE_M_LN10 2.30258509299404568402
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#define LOVE_M_PI 3.14159265358979323846
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#define LOVE_M_PI_2 1.57079632679489661923
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#define LOVE_M_PI_4 0.785398163397448309616
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#define LOVE_M_1_PI 0.318309886183790671538
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#define LOVE_M_2_PI 0.636619772367581343076
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#define LOVE_M_2_SQRTPI 1.12837916709551257390
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#define LOVE_M_SQRT2 1.41421356237309504880
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#define LOVE_M_SQRT1_2 0.707106781186547524401
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#define LOVE_M_TORAD (float)(LOVE_M_PI/180.0)
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#define LOVE_M_TODEG (float)(180.0/LOVE_M_PI)
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#define LOVE_TORAD(x) (float)(x*LOVE_M_TORAD)
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#define LOVE_TODEG(x) (float)(x*LOVE_M_TODEG)
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namespace love
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{
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struct vertex
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{
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unsigned char r, g, b, a;
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float x, y;
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float s, t;
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};
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inline int next_p2(int x)
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{
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x += (x == 0);
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x--;
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for (unsigned int i = 1; i < sizeof(int)*CHAR_BIT; i <<= 1) x |= x >> i;
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return ++x;
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}
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inline float next_p2(float x)
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{
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return static_cast<float>(next_p2(static_cast<int>(x)));
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}
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/**
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* Draws a random number from a uniform distribution.
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* @returns Uniformly distributed random number in [0:1).
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*/
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inline float random()
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{
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// to satisfy picky compilers...
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return float(double(rand() % RAND_MAX) / double(RAND_MAX));
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}
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/**
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* Draws a random number from a uniform distribution.
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* @return Uniformly distributed random number in [0:max).
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*/
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inline float random(float max)
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{
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return random() * max;
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}
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/**
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* Draws a random number from a uniform distribution.
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* @return Uniformly distributed random number in [min:max).
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*/
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inline float random(float min, float max)
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{
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return random(max - min) + min;
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}
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/**
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* Draws a random number from a normal/gaussian distribution.
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* @param o Standard deviation of the distribution.
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* @returns Normal distributed random number with mean 0 and variance o^2.
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*/
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float random_normal(float o = 1.);
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#define random_gaussian random_normal
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} // love
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#endif // LOVE_MATH_H
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