1 | // |
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2 | // Lol Engine |
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3 | // |
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4 | // Copyright: (c) 2010-2011 Sam Hocevar <sam@hocevar.net> |
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5 | // This program is free software; you can redistribute it and/or |
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6 | // modify it under the terms of the Do What The Fuck You Want To |
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7 | // Public License, Version 2, as published by Sam Hocevar. See |
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8 | // http://sam.zoy.org/projects/COPYING.WTFPL for more details. |
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9 | // |
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10 | |
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11 | // |
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12 | // The Half class |
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13 | // -------------- |
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14 | // |
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15 | |
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16 | #if !defined __LOL_HALF_H__ |
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17 | #define __LOL_HALF_H__ |
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18 | |
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19 | #include <cstdio> |
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20 | #include <stdint.h> |
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21 | |
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22 | namespace lol |
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23 | { |
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24 | |
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25 | class half |
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26 | { |
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27 | public: |
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28 | /* Constructors. Always inline so that the code can work in registers |
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29 | * instead of calling routines with the hidden "this" parameter. */ |
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30 | inline half() { } |
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31 | inline half(float f) { *this = makefast(f); } |
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32 | |
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33 | inline int is_nan() const |
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34 | { |
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35 | return ((bits & 0x7c00u) == 0x7c00u) && (bits & 0x03ffu); |
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36 | } |
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37 | |
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38 | inline int is_finite() const |
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39 | { |
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40 | return (bits & 0x7c00u) != 0x7c00u; |
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41 | } |
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42 | |
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43 | inline int is_inf() const |
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44 | { |
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45 | return (uint16_t)(bits << 1) == (0x7c00u << 1); |
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46 | } |
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47 | |
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48 | inline int is_normal() const |
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49 | { |
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50 | return (is_finite() && (bits & 0x7c00u)) || ((bits & 0x7fffu) == 0); |
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51 | } |
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52 | |
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53 | /* Cast to other types */ |
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54 | inline operator float() const { return tofloat(*this); } |
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55 | inline operator int() const { return (int)tofloat(*this); } |
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56 | |
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57 | static float tofloat(half h); |
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58 | |
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59 | /* Array conversions */ |
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60 | static size_t convert(half *dst, float const *src, size_t nelem); |
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61 | static size_t convert(float *dst, half const *src, size_t nelem); |
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62 | |
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63 | /* Operations */ |
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64 | inline half operator -() { return makebits(bits ^ 0x8000u); } |
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65 | inline half &operator +=(float f) { return (*this = (half)(*this + f)); } |
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66 | inline half &operator -=(float f) { return (*this = (half)(*this - f)); } |
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67 | inline half &operator *=(float f) { return (*this = (half)(*this * f)); } |
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68 | inline half &operator /=(float f) { return (*this = (half)(*this / f)); } |
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69 | inline half &operator +=(half h) { return (*this = (half)(*this + h)); } |
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70 | inline half &operator -=(half h) { return (*this = (half)(*this - h)); } |
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71 | inline half &operator *=(half h) { return (*this = (half)(*this * h)); } |
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72 | inline half &operator /=(half h) { return (*this = (half)(*this / h)); } |
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73 | |
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74 | inline float operator +(float f) const { return (float)*this + f; } |
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75 | inline float operator -(float f) const { return (float)*this - f; } |
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76 | inline float operator *(float f) const { return (float)*this * f; } |
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77 | inline float operator /(float f) const { return (float)*this / f; } |
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78 | inline float operator +(half h) const { return (float)*this + (float)h; } |
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79 | inline float operator -(half h) const { return (float)*this - (float)h; } |
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80 | inline float operator *(half h) const { return (float)*this * (float)h; } |
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81 | inline float operator /(half h) const { return (float)*this / (float)h; } |
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82 | |
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83 | /* Factories */ |
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84 | static half makefast(float f); |
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85 | static half makeaccurate(float f); |
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86 | static inline half makebits(uint16_t x) |
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87 | { |
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88 | half ret; |
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89 | ret.bits = x; |
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90 | return ret; |
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91 | } |
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92 | |
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93 | /* Internal representation */ |
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94 | uint16_t bits; |
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95 | }; |
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96 | |
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97 | inline float &operator +=(float &f, half h) { return f += (float)h; } |
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98 | inline float &operator -=(float &f, half h) { return f -= (float)h; } |
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99 | inline float &operator *=(float &f, half h) { return f *= (float)h; } |
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100 | inline float &operator /=(float &f, half h) { return f /= (float)h; } |
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101 | |
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102 | inline float operator +(float f, half h) { return f + (float)h; } |
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103 | inline float operator -(float f, half h) { return f - (float)h; } |
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104 | inline float operator *(float f, half h) { return f * (float)h; } |
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105 | inline float operator /(float f, half h) { return f / (float)h; } |
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106 | |
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107 | } /* namespace lol */ |
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108 | |
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109 | #endif // __LOL_HALF_H__ |
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110 | |
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