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Diffstat (limited to 'src/common/math_util.h')
| -rw-r--r-- | src/common/math_util.h | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/src/common/math_util.h b/src/common/math_util.h new file mode 100644 index 000000000..4410c5e01 --- /dev/null +++ b/src/common/math_util.h @@ -0,0 +1,200 @@ +// Copyright 2013 Dolphin Emulator Project +// Licensed under GPLv2 +// Refer to the license.txt file included. + + +#ifndef _MATH_UTIL_H_ +#define _MATH_UTIL_H_ + +#include "common.h" + +#include <vector> + +namespace MathUtil +{ + +static const u64 DOUBLE_SIGN = 0x8000000000000000ULL, + DOUBLE_EXP = 0x7FF0000000000000ULL, + DOUBLE_FRAC = 0x000FFFFFFFFFFFFFULL, + DOUBLE_ZERO = 0x0000000000000000ULL; + +static const u32 FLOAT_SIGN = 0x80000000, + FLOAT_EXP = 0x7F800000, + FLOAT_FRAC = 0x007FFFFF, + FLOAT_ZERO = 0x00000000; + +union IntDouble { + double d; + u64 i; +}; +union IntFloat { + float f; + u32 i; +}; + +inline bool IsNAN(double d) +{ + IntDouble x; x.d = d; + return ( ((x.i & DOUBLE_EXP) == DOUBLE_EXP) && + ((x.i & DOUBLE_FRAC) != DOUBLE_ZERO) ); +} + +inline bool IsQNAN(double d) +{ + IntDouble x; x.d = d; + return ( ((x.i & DOUBLE_EXP) == DOUBLE_EXP) && + ((x.i & 0x0007fffffffffffULL) == 0x000000000000000ULL) && + ((x.i & 0x000800000000000ULL) == 0x000800000000000ULL) ); +} + +inline bool IsSNAN(double d) +{ + IntDouble x; x.d = d; + return( ((x.i & DOUBLE_EXP) == DOUBLE_EXP) && + ((x.i & DOUBLE_FRAC) != DOUBLE_ZERO) && + ((x.i & 0x0008000000000000ULL) == DOUBLE_ZERO) ); +} + +inline float FlushToZero(float f) +{ + IntFloat x; x.f = f; + if ((x.i & FLOAT_EXP) == 0) + x.i &= FLOAT_SIGN; // turn into signed zero + return x.f; +} + +inline double FlushToZeroAsFloat(double d) +{ + IntDouble x; x.d = d; + if ((x.i & DOUBLE_EXP) < 0x3800000000000000ULL) + x.i &= DOUBLE_SIGN; // turn into signed zero + return x.d; +} + +enum PPCFpClass +{ + PPC_FPCLASS_QNAN = 0x11, + PPC_FPCLASS_NINF = 0x9, + PPC_FPCLASS_NN = 0x8, + PPC_FPCLASS_ND = 0x18, + PPC_FPCLASS_NZ = 0x12, + PPC_FPCLASS_PZ = 0x2, + PPC_FPCLASS_PD = 0x14, + PPC_FPCLASS_PN = 0x4, + PPC_FPCLASS_PINF = 0x5, +}; + +// Uses PowerPC conventions for the return value, so it can be easily +// used directly in CPU emulation. +u32 ClassifyDouble(double dvalue); +// More efficient float version. +u32 ClassifyFloat(float fvalue); + +template<class T> +struct Rectangle +{ + T left; + T top; + T right; + T bottom; + + Rectangle() + { } + + Rectangle(T theLeft, T theTop, T theRight, T theBottom) + : left(theLeft), top(theTop), right(theRight), bottom(theBottom) + { } + + bool operator==(const Rectangle& r) { return left==r.left && top==r.top && right==r.right && bottom==r.bottom; } + + T GetWidth() const { return abs(right - left); } + T GetHeight() const { return abs(bottom - top); } + + // If the rectangle is in a coordinate system with a lower-left origin, use + // this Clamp. + void ClampLL(T x1, T y1, T x2, T y2) + { + if (left < x1) left = x1; + if (right > x2) right = x2; + if (top > y1) top = y1; + if (bottom < y2) bottom = y2; + } + + // If the rectangle is in a coordinate system with an upper-left origin, + // use this Clamp. + void ClampUL(T x1, T y1, T x2, T y2) + { + if (left < x1) left = x1; + if (right > x2) right = x2; + if (top < y1) top = y1; + if (bottom > y2) bottom = y2; + } +}; + +} // namespace MathUtil + +inline float pow2f(float x) {return x * x;} +inline double pow2(double x) {return x * x;} + +float MathFloatVectorSum(const std::vector<float>&); + +#define ROUND_UP(x, a) (((x) + (a) - 1) & ~((a) - 1)) +#define ROUND_DOWN(x, a) ((x) & ~((a) - 1)) + +// Rounds down. 0 -> undefined +inline u64 Log2(u64 val) +{ +#if defined(__GNUC__) + return 63 - __builtin_clzll(val); + +#elif defined(_MSC_VER) && defined(_M_X64) + unsigned long result = -1; + _BitScanReverse64(&result, val); + return result; + +#else + u64 result = -1; + while (val != 0) + { + val >>= 1; + ++result; + } + return result; +#endif +} + +// Tiny matrix/vector library. +// Used for things like Free-Look in the gfx backend. + +class Matrix33 +{ +public: + static void LoadIdentity(Matrix33 &mtx); + + // set mtx to be a rotation matrix around the x axis + static void RotateX(Matrix33 &mtx, float rad); + // set mtx to be a rotation matrix around the y axis + static void RotateY(Matrix33 &mtx, float rad); + + // set result = a x b + static void Multiply(const Matrix33 &a, const Matrix33 &b, Matrix33 &result); + static void Multiply(const Matrix33 &a, const float vec[3], float result[3]); + + float data[9]; +}; + +class Matrix44 +{ +public: + static void LoadIdentity(Matrix44 &mtx); + static void LoadMatrix33(Matrix44 &mtx, const Matrix33 &m33); + static void Set(Matrix44 &mtx, const float mtxArray[16]); + + static void Translate(Matrix44 &mtx, const float vec[3]); + + static void Multiply(const Matrix44 &a, const Matrix44 &b, Matrix44 &result); + + float data[16]; +}; + +#endif // _MATH_UTIL_H_ |