Mathias Agopian | 984826c | 2011-05-17 22:54:42 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2011 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef ANDROID_VEC_H |
| 18 | #define ANDROID_VEC_H |
| 19 | |
| 20 | #include <math.h> |
| 21 | |
| 22 | #include <stdint.h> |
| 23 | #include <stddef.h> |
| 24 | |
| 25 | #include "traits.h" |
| 26 | |
| 27 | // ----------------------------------------------------------------------- |
| 28 | |
| 29 | #define PURE __attribute__((pure)) |
| 30 | |
| 31 | namespace android { |
| 32 | |
| 33 | // ----------------------------------------------------------------------- |
| 34 | // non-inline helpers |
| 35 | |
| 36 | template <typename TYPE, size_t SIZE> |
| 37 | class vec; |
| 38 | |
| 39 | template <typename TYPE, size_t SIZE> |
| 40 | class vbase; |
| 41 | |
| 42 | namespace helpers { |
| 43 | |
| 44 | template <typename T> inline T min(T a, T b) { return a<b ? a : b; } |
| 45 | template <typename T> inline T max(T a, T b) { return a>b ? a : b; } |
| 46 | |
| 47 | template < template<typename T, size_t S> class VEC, |
| 48 | typename TYPE, size_t SIZE, size_t S> |
| 49 | vec<TYPE, SIZE>& doAssign( |
| 50 | vec<TYPE, SIZE>& lhs, const VEC<TYPE, S>& rhs) { |
| 51 | const size_t minSize = min(SIZE, S); |
| 52 | const size_t maxSize = max(SIZE, S); |
| 53 | for (size_t i=0 ; i<minSize ; i++) |
| 54 | lhs[i] = rhs[i]; |
| 55 | for (size_t i=minSize ; i<maxSize ; i++) |
| 56 | lhs[i] = 0; |
| 57 | return lhs; |
| 58 | } |
| 59 | |
| 60 | |
| 61 | template < |
| 62 | template<typename T, size_t S> class VLHS, |
| 63 | template<typename T, size_t S> class VRHS, |
| 64 | typename TYPE, |
| 65 | size_t SIZE |
| 66 | > |
| 67 | VLHS<TYPE, SIZE> PURE doAdd( |
| 68 | const VLHS<TYPE, SIZE>& lhs, |
| 69 | const VRHS<TYPE, SIZE>& rhs) { |
| 70 | VLHS<TYPE, SIZE> r; |
| 71 | for (size_t i=0 ; i<SIZE ; i++) |
| 72 | r[i] = lhs[i] + rhs[i]; |
| 73 | return r; |
| 74 | } |
| 75 | |
| 76 | template < |
| 77 | template<typename T, size_t S> class VLHS, |
| 78 | template<typename T, size_t S> class VRHS, |
| 79 | typename TYPE, |
| 80 | size_t SIZE |
| 81 | > |
| 82 | VLHS<TYPE, SIZE> PURE doSub( |
| 83 | const VLHS<TYPE, SIZE>& lhs, |
| 84 | const VRHS<TYPE, SIZE>& rhs) { |
| 85 | VLHS<TYPE, SIZE> r; |
| 86 | for (size_t i=0 ; i<SIZE ; i++) |
| 87 | r[i] = lhs[i] - rhs[i]; |
| 88 | return r; |
| 89 | } |
| 90 | |
| 91 | template < |
| 92 | template<typename T, size_t S> class VEC, |
| 93 | typename TYPE, |
| 94 | size_t SIZE |
| 95 | > |
| 96 | VEC<TYPE, SIZE> PURE doMulScalar( |
| 97 | const VEC<TYPE, SIZE>& lhs, |
| 98 | typename TypeTraits<TYPE>::ParameterType rhs) { |
| 99 | VEC<TYPE, SIZE> r; |
| 100 | for (size_t i=0 ; i<SIZE ; i++) |
| 101 | r[i] = lhs[i] * rhs; |
| 102 | return r; |
| 103 | } |
| 104 | |
| 105 | template < |
| 106 | template<typename T, size_t S> class VEC, |
| 107 | typename TYPE, |
| 108 | size_t SIZE |
| 109 | > |
| 110 | VEC<TYPE, SIZE> PURE doScalarMul( |
| 111 | typename TypeTraits<TYPE>::ParameterType lhs, |
| 112 | const VEC<TYPE, SIZE>& rhs) { |
| 113 | VEC<TYPE, SIZE> r; |
| 114 | for (size_t i=0 ; i<SIZE ; i++) |
| 115 | r[i] = lhs * rhs[i]; |
| 116 | return r; |
| 117 | } |
| 118 | |
| 119 | }; // namespace helpers |
| 120 | |
| 121 | // ----------------------------------------------------------------------- |
| 122 | // Below we define the mathematical operators for vectors. |
| 123 | // We use template template arguments so we can generically |
| 124 | // handle the case where the right-hand-size and left-hand-side are |
| 125 | // different vector types (but with same value_type and size). |
| 126 | // This is needed for performance when using ".xy{z}" element access |
| 127 | // on vec<>. Without this, an extra conversion to vec<> would be needed. |
| 128 | // |
| 129 | // example: |
| 130 | // vec4_t a; |
| 131 | // vec3_t b; |
| 132 | // vec3_t c = a.xyz + b; |
| 133 | // |
| 134 | // "a.xyz + b" is a mixed-operation between a vbase<> and a vec<>, requiring |
| 135 | // a conversion of vbase<> to vec<>. The template gunk below avoids this, |
| 136 | // by allowing the addition on these different vector types directly |
| 137 | // |
| 138 | |
| 139 | template < |
| 140 | template<typename T, size_t S> class VLHS, |
| 141 | template<typename T, size_t S> class VRHS, |
| 142 | typename TYPE, |
| 143 | size_t SIZE |
| 144 | > |
| 145 | inline VLHS<TYPE, SIZE> PURE operator + ( |
| 146 | const VLHS<TYPE, SIZE>& lhs, |
| 147 | const VRHS<TYPE, SIZE>& rhs) { |
| 148 | return helpers::doAdd(lhs, rhs); |
| 149 | } |
| 150 | |
| 151 | template < |
| 152 | template<typename T, size_t S> class VLHS, |
| 153 | template<typename T, size_t S> class VRHS, |
| 154 | typename TYPE, |
| 155 | size_t SIZE |
| 156 | > |
| 157 | inline VLHS<TYPE, SIZE> PURE operator - ( |
| 158 | const VLHS<TYPE, SIZE>& lhs, |
| 159 | const VRHS<TYPE, SIZE>& rhs) { |
| 160 | return helpers::doSub(lhs, rhs); |
| 161 | } |
| 162 | |
| 163 | template < |
| 164 | template<typename T, size_t S> class VEC, |
| 165 | typename TYPE, |
| 166 | size_t SIZE |
| 167 | > |
| 168 | inline VEC<TYPE, SIZE> PURE operator * ( |
| 169 | const VEC<TYPE, SIZE>& lhs, |
| 170 | typename TypeTraits<TYPE>::ParameterType rhs) { |
| 171 | return helpers::doMulScalar(lhs, rhs); |
| 172 | } |
| 173 | |
| 174 | template < |
| 175 | template<typename T, size_t S> class VEC, |
| 176 | typename TYPE, |
| 177 | size_t SIZE |
| 178 | > |
| 179 | inline VEC<TYPE, SIZE> PURE operator * ( |
| 180 | typename TypeTraits<TYPE>::ParameterType lhs, |
| 181 | const VEC<TYPE, SIZE>& rhs) { |
| 182 | return helpers::doScalarMul(lhs, rhs); |
| 183 | } |
| 184 | |
| 185 | |
| 186 | template < |
| 187 | template<typename T, size_t S> class VLHS, |
| 188 | template<typename T, size_t S> class VRHS, |
| 189 | typename TYPE, |
| 190 | size_t SIZE |
| 191 | > |
| 192 | TYPE PURE dot_product( |
| 193 | const VLHS<TYPE, SIZE>& lhs, |
| 194 | const VRHS<TYPE, SIZE>& rhs) { |
| 195 | TYPE r(0); |
| 196 | for (size_t i=0 ; i<SIZE ; i++) |
| 197 | r += lhs[i] * rhs[i]; |
| 198 | return r; |
| 199 | } |
| 200 | |
| 201 | template < |
| 202 | template<typename T, size_t S> class V, |
| 203 | typename TYPE, |
| 204 | size_t SIZE |
| 205 | > |
| 206 | TYPE PURE length(const V<TYPE, SIZE>& v) { |
| 207 | return sqrt(dot_product(v, v)); |
| 208 | } |
| 209 | |
| 210 | template < |
| 211 | template<typename T, size_t S> class VLHS, |
| 212 | template<typename T, size_t S> class VRHS, |
| 213 | typename TYPE |
| 214 | > |
| 215 | VLHS<TYPE, 3> PURE cross_product( |
| 216 | const VLHS<TYPE, 3>& u, |
| 217 | const VRHS<TYPE, 3>& v) { |
| 218 | VLHS<TYPE, 3> r; |
| 219 | r.x = u.y*v.z - u.z*v.y; |
| 220 | r.y = u.z*v.x - u.x*v.z; |
| 221 | r.z = u.x*v.y - u.y*v.x; |
| 222 | return r; |
| 223 | } |
| 224 | |
| 225 | |
| 226 | template <typename TYPE, size_t SIZE> |
| 227 | vec<TYPE, SIZE> PURE operator - (const vec<TYPE, SIZE>& lhs) { |
| 228 | vec<TYPE, SIZE> r; |
| 229 | for (size_t i=0 ; i<SIZE ; i++) |
| 230 | r[i] = -lhs[i]; |
| 231 | return r; |
| 232 | } |
| 233 | |
| 234 | // ----------------------------------------------------------------------- |
| 235 | |
| 236 | // This our basic vector type, it just implements the data storage |
| 237 | // and accessors. |
| 238 | |
| 239 | template <typename TYPE, size_t SIZE> |
| 240 | struct vbase { |
| 241 | TYPE v[SIZE]; |
| 242 | inline const TYPE& operator[](size_t i) const { return v[i]; } |
| 243 | inline TYPE& operator[](size_t i) { return v[i]; } |
| 244 | }; |
| 245 | template<> struct vbase<float, 2> { |
| 246 | union { |
| 247 | float v[2]; |
| 248 | struct { float x, y; }; |
| 249 | struct { float s, t; }; |
| 250 | }; |
| 251 | inline const float& operator[](size_t i) const { return v[i]; } |
| 252 | inline float& operator[](size_t i) { return v[i]; } |
| 253 | }; |
| 254 | template<> struct vbase<float, 3> { |
| 255 | union { |
| 256 | float v[3]; |
| 257 | struct { float x, y, z; }; |
| 258 | struct { float s, t, r; }; |
| 259 | vbase<float, 2> xy; |
| 260 | vbase<float, 2> st; |
| 261 | }; |
| 262 | inline const float& operator[](size_t i) const { return v[i]; } |
| 263 | inline float& operator[](size_t i) { return v[i]; } |
| 264 | }; |
| 265 | template<> struct vbase<float, 4> { |
| 266 | union { |
| 267 | float v[4]; |
| 268 | struct { float x, y, z, w; }; |
| 269 | struct { float s, t, r, q; }; |
| 270 | vbase<float, 3> xyz; |
| 271 | vbase<float, 3> str; |
| 272 | vbase<float, 2> xy; |
| 273 | vbase<float, 2> st; |
| 274 | }; |
| 275 | inline const float& operator[](size_t i) const { return v[i]; } |
| 276 | inline float& operator[](size_t i) { return v[i]; } |
| 277 | }; |
| 278 | |
| 279 | // ----------------------------------------------------------------------- |
| 280 | |
| 281 | template <typename TYPE, size_t SIZE> |
| 282 | class vec : public vbase<TYPE, SIZE> |
| 283 | { |
| 284 | typedef typename TypeTraits<TYPE>::ParameterType pTYPE; |
| 285 | typedef vbase<TYPE, SIZE> base; |
| 286 | |
| 287 | public: |
| 288 | // STL-like interface. |
| 289 | typedef TYPE value_type; |
| 290 | typedef TYPE& reference; |
| 291 | typedef TYPE const& const_reference; |
| 292 | typedef size_t size_type; |
| 293 | |
| 294 | typedef TYPE* iterator; |
| 295 | typedef TYPE const* const_iterator; |
| 296 | iterator begin() { return base::v; } |
| 297 | iterator end() { return base::v + SIZE; } |
| 298 | const_iterator begin() const { return base::v; } |
| 299 | const_iterator end() const { return base::v + SIZE; } |
| 300 | size_type size() const { return SIZE; } |
| 301 | |
| 302 | // ----------------------------------------------------------------------- |
| 303 | // default constructors |
| 304 | |
| 305 | vec() { } |
| 306 | vec(const vec& rhs) : base(rhs) { } |
| 307 | vec(const base& rhs) : base(rhs) { } |
| 308 | |
| 309 | // ----------------------------------------------------------------------- |
| 310 | // conversion constructors |
| 311 | |
| 312 | vec(pTYPE rhs) { |
| 313 | for (size_t i=0 ; i<SIZE ; i++) |
| 314 | base::operator[](i) = rhs; |
| 315 | } |
| 316 | |
| 317 | template < template<typename T, size_t S> class VEC, size_t S> |
| 318 | explicit vec(const VEC<TYPE, S>& rhs) { |
| 319 | helpers::doAssign(*this, rhs); |
| 320 | } |
| 321 | |
| 322 | explicit vec(TYPE const* array) { |
| 323 | for (size_t i=0 ; i<SIZE ; i++) |
| 324 | base::operator[](i) = array[i]; |
| 325 | } |
| 326 | |
| 327 | // ----------------------------------------------------------------------- |
| 328 | // Assignment |
| 329 | |
| 330 | vec& operator = (const vec& rhs) { |
| 331 | base::operator=(rhs); |
| 332 | return *this; |
| 333 | } |
| 334 | |
| 335 | vec& operator = (const base& rhs) { |
| 336 | base::operator=(rhs); |
| 337 | return *this; |
| 338 | } |
| 339 | |
| 340 | vec& operator = (pTYPE rhs) { |
| 341 | for (size_t i=0 ; i<SIZE ; i++) |
| 342 | base::operator[](i) = rhs; |
| 343 | return *this; |
| 344 | } |
| 345 | |
| 346 | template < template<typename T, size_t S> class VEC, size_t S> |
| 347 | vec& operator = (const VEC<TYPE, S>& rhs) { |
| 348 | return helpers::doAssign(*this, rhs); |
| 349 | } |
| 350 | |
| 351 | // ----------------------------------------------------------------------- |
| 352 | // operation-assignment |
| 353 | |
| 354 | vec& operator += (const vec& rhs); |
| 355 | vec& operator -= (const vec& rhs); |
| 356 | vec& operator *= (pTYPE rhs); |
| 357 | |
| 358 | // ----------------------------------------------------------------------- |
| 359 | // non-member function declaration and definition |
| 360 | // NOTE: we declare the non-member function as friend inside the class |
| 361 | // so that they are known to the compiler when the class is instantiated. |
| 362 | // This helps the compiler doing template argument deduction when the |
| 363 | // passed types are not identical. Essentially this helps with |
| 364 | // type conversion so that you can multiply a vec<float> by an scalar int |
| 365 | // (for instance). |
| 366 | |
| 367 | friend inline vec PURE operator + (const vec& lhs, const vec& rhs) { |
| 368 | return helpers::doAdd(lhs, rhs); |
| 369 | } |
| 370 | friend inline vec PURE operator - (const vec& lhs, const vec& rhs) { |
| 371 | return helpers::doSub(lhs, rhs); |
| 372 | } |
| 373 | friend inline vec PURE operator * (const vec& lhs, pTYPE v) { |
| 374 | return helpers::doMulScalar(lhs, v); |
| 375 | } |
| 376 | friend inline vec PURE operator * (pTYPE v, const vec& rhs) { |
| 377 | return helpers::doScalarMul(v, rhs); |
| 378 | } |
| 379 | friend inline TYPE PURE dot_product(const vec& lhs, const vec& rhs) { |
| 380 | return android::dot_product(lhs, rhs); |
| 381 | } |
| 382 | }; |
| 383 | |
| 384 | // ----------------------------------------------------------------------- |
| 385 | |
| 386 | template <typename TYPE, size_t SIZE> |
| 387 | vec<TYPE, SIZE>& vec<TYPE, SIZE>::operator += (const vec<TYPE, SIZE>& rhs) { |
| 388 | vec<TYPE, SIZE>& lhs(*this); |
| 389 | for (size_t i=0 ; i<SIZE ; i++) |
| 390 | lhs[i] += rhs[i]; |
| 391 | return lhs; |
| 392 | } |
| 393 | |
| 394 | template <typename TYPE, size_t SIZE> |
| 395 | vec<TYPE, SIZE>& vec<TYPE, SIZE>::operator -= (const vec<TYPE, SIZE>& rhs) { |
| 396 | vec<TYPE, SIZE>& lhs(*this); |
| 397 | for (size_t i=0 ; i<SIZE ; i++) |
| 398 | lhs[i] -= rhs[i]; |
| 399 | return lhs; |
| 400 | } |
| 401 | |
| 402 | template <typename TYPE, size_t SIZE> |
| 403 | vec<TYPE, SIZE>& vec<TYPE, SIZE>::operator *= (vec<TYPE, SIZE>::pTYPE rhs) { |
| 404 | vec<TYPE, SIZE>& lhs(*this); |
| 405 | for (size_t i=0 ; i<SIZE ; i++) |
| 406 | lhs[i] *= rhs; |
| 407 | return lhs; |
| 408 | } |
| 409 | |
| 410 | // ----------------------------------------------------------------------- |
| 411 | |
| 412 | typedef vec<float, 2> vec2_t; |
| 413 | typedef vec<float, 3> vec3_t; |
| 414 | typedef vec<float, 4> vec4_t; |
| 415 | |
| 416 | // ----------------------------------------------------------------------- |
| 417 | |
| 418 | }; // namespace android |
| 419 | |
| 420 | #endif /* ANDROID_VEC_H */ |