1 | #pragma once |
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2 | #include <math.hfa> |
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3 | #include <iostream.hfa> |
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4 | |
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5 | trait vec2_t(otype T) { |
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6 | void ?{}(T&, int); |
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7 | T ?=?(T&, zero_t); |
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8 | T ?-?(T, T); |
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9 | T -?(T); |
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10 | T ?+?(T, T); |
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11 | T ?*?(T, T); |
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12 | T ?/?(T, T); |
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13 | int ?==?(T, T); |
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14 | int ?<?(T, T); |
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15 | T sqrt(T); |
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16 | }; |
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17 | |
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18 | static inline { |
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19 | // int |
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20 | int ?=?(int& n, zero_t) { return n = 0.f; } |
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21 | int sqrt(int a) { return sqrt((float)a); } |
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22 | /* float */ |
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23 | void ?{}(float& a, int b) { a = b; } |
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24 | float ?=?(float& n, zero_t) { return n = 0.f; } |
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25 | /* double */ |
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26 | void ?{}(double& a, int b) { a = b; } |
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27 | double ?=?(double& n, zero_t) { return n = 0L; } |
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28 | // long double |
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29 | void ?{}(long double& a, int b) { a = b; } |
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30 | long double ?=?(long double& n, zero_t) { return n = 0L; } |
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31 | } |
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32 | |
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33 | forall(otype T | vec2_t(T)) { |
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34 | struct vec2 { |
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35 | T x, y; |
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36 | }; |
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37 | } |
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38 | |
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39 | /* static inline { */ |
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40 | forall(otype T | vec2_t(T)) { |
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41 | static inline { |
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42 | |
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43 | // Constructors |
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44 | |
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45 | void ?{}(vec2(T)& v, T x, T y) { |
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46 | v.[x, y] = [x, y]; |
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47 | } |
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48 | void ?{}(vec2(T)& vec, zero_t) with (vec) { |
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49 | x = y = 0; |
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50 | } |
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51 | void ?{}(vec2(T)& vec, T val) with (vec) { |
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52 | x = y = val; |
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53 | } |
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54 | void ?{}(vec2(T)& vec, vec2(T) other) with (vec) { |
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55 | [x,y] = other.[x,y]; |
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56 | } |
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57 | |
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58 | // Assignment |
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59 | void ?=?(vec2(T)& vec, vec2(T) other) with (vec) { |
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60 | [x,y] = other.[x,y]; |
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61 | } |
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62 | void ?=?(vec2(T)& vec, zero_t) with (vec) { |
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63 | x = y = 0; |
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64 | } |
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65 | |
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66 | // Primitive mathematical operations |
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67 | |
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68 | // Subtraction |
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69 | vec2(T) ?-?(vec2(T) u, vec2(T) v) { // TODO( can't make this const ref ) |
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70 | return [u.x - v.x, u.y - v.y]; |
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71 | } |
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72 | vec2(T)& ?-=?(vec2(T)& u, vec2(T) v) { |
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73 | u = u - v; |
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74 | return u; |
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75 | } |
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76 | vec2(T) -?(vec2(T)& v) with (v) { |
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77 | return [-x, -y]; |
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78 | } |
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79 | |
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80 | // Addition |
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81 | vec2(T) ?+?(vec2(T) u, vec2(T) v) { // TODO( can't make this const ref ) |
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82 | return [u.x + v.x, u.y + v.y]; |
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83 | } |
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84 | vec2(T)& ?+=?(vec2(T)& u, vec2(T) v) { |
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85 | u = u + v; |
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86 | return u; |
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87 | } |
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88 | |
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89 | // Scalar Multiplication |
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90 | vec2(T) ?*?(vec2(T) v, T scalar) with (v) { // TODO (can't make this const ref) |
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91 | return [x * scalar, y * scalar]; |
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92 | } |
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93 | vec2(T) ?*?(T scalar, vec2(T) v) { // TODO (can't make this const ref) |
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94 | return v * scalar; |
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95 | } |
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96 | vec2(T)& ?*=?(vec2(T)& v, T scalar) { |
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97 | v = v * scalar; |
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98 | return v; |
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99 | } |
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100 | |
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101 | |
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102 | // Scalar Division |
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103 | vec2(T) ?/?(vec2(T) v, T scalar) with (v) { |
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104 | return [x / scalar, y / scalar]; |
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105 | } |
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106 | vec2(T)& ?/=?(vec2(T)& v, T scalar) with (v) { |
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107 | v = v / scalar; |
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108 | return v; |
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109 | } |
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110 | // Relational Operators |
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111 | bool ?==?(vec2(T) u, vec2(T) v) with (u) { |
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112 | return x == v.x && y == v.y; |
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113 | } |
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114 | bool ?!=?(vec2(T) u, vec2(T) v) { |
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115 | return !(u == v); |
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116 | } |
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117 | |
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118 | T dot(vec2(T) u, vec2(T) v) { |
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119 | return u.x * v.x + u.y * v.y; |
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120 | } |
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121 | |
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122 | T length(vec2(T) v) { |
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123 | return sqrt(dot(v, v)); |
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124 | } |
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125 | |
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126 | T length_squared(vec2(T) v) { |
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127 | return dot(v, v); |
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128 | } |
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129 | |
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130 | T distance(vec2(T) v1, vec2(T) v2) { |
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131 | return length(v1 - v2); |
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132 | } |
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133 | |
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134 | vec2(T) normalize(vec2(T) v) { |
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135 | return v / sqrt(dot(v, v)); |
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136 | } |
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137 | |
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138 | // Project vector u onto vector v |
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139 | vec2(T) project(vec2(T) u, vec2(T) v) { |
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140 | vec2(T) v_norm = normalize(v); |
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141 | return v_norm * dot(u, v_norm); |
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142 | } |
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143 | |
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144 | // Reflect incident vector v with respect to surface with normal n |
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145 | vec2(T) reflect(vec2(T) v, vec2(T) n) { |
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146 | return v - (T){2} * project(v, n); |
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147 | } |
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148 | |
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149 | // Refract incident vector v with respect to surface with normal n |
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150 | // eta is the ratio of indices of refraction between starting material and |
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151 | // entering material (i.e., from air to water, eta = 1/1.33) |
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152 | // v and n must already be normalized |
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153 | vec2(T) refract(vec2(T) v, vec2(T) n, T eta) { |
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154 | T dotValue = dot(n, v); |
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155 | T k = (T){1} - eta * eta * ((T){1} - dotValue * dotValue); |
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156 | if (k < (T){0}) { |
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157 | return 0; |
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158 | } |
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159 | return eta * v - (eta * dotValue + sqrt(k)) * n; |
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160 | } |
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161 | |
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162 | // Given a perturbed normal and a geometric normal, |
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163 | // flip the perturbed normal if the geometric normal is pointing away |
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164 | // from the observer. |
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165 | // n is the perturbed vector that we want to align |
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166 | // i is the incident vector |
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167 | // ng is the geometric normal of the surface |
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168 | vec2(T) faceforward(vec2(T) n, vec2(T) i, vec2(T) ng) { |
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169 | return dot(ng, i) < (T){0} ? n : -n; |
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170 | } |
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171 | } |
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172 | } |
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173 | |
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174 | forall(dtype ostype, otype T | writeable(T, ostype) | vec2_t(T)) { |
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175 | ostype & ?|?( ostype & os, vec2(T) v) with (v) { |
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176 | return os | '<' | x | ',' | y | '>'; |
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177 | } |
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178 | void ?|?( ostype & os, vec2(T) v ) with (v) { |
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179 | (ostype &)(os | v); ends(os); |
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180 | } |
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181 | } |
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