src/mesa/main/macros.h

   1 /**
   2  * \file macros.h
   3  * A collection of useful macros.
   4  */
   5
   6 /*
   7  * Mesa 3-D graphics library
   8  * Version:  6.5.2
   9  *
  10  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a
  13  * copy of this software and associated documentation files (the "Software"),
  14  * to deal in the Software without restriction, including without limitation
  15  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  16  * and/or sell copies of the Software, and to permit persons to whom the
  17  * Software is furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included
  20  * in all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  23  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  26  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  27  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28  */
  29
  30
  31 #ifndef MACROS_H
  32 #define MACROS_H
  33
  34 #include "imports.h"
  35
  36
  37 /**
  38  * \name Integer / float conversion for colors, normals, etc.
  39  */
  40 /*@{*/
  41
  42 /** Convert GLubyte in [0,255] to GLfloat in [0.0,1.0] */
  43 extern GLfloat _mesa_ubyte_to_float_color_tab[256];
  44 #define UBYTE_TO_FLOAT(u) _mesa_ubyte_to_float_color_tab[(unsigned int)(u)]
  45
  46 /** Convert GLfloat in [0.0,1.0] to GLubyte in [0,255] */
  47 #define FLOAT_TO_UBYTE(X)   ((GLubyte) (GLint) ((X) * 255.0F))
  48
  49
  50 /** Convert GLbyte in [-128,127] to GLfloat in [-1.0,1.0] */
  51 #define BYTE_TO_FLOAT(B)    ((2.0F * (B) + 1.0F) * (1.0F/255.0F))
  52
  53 /** Convert GLfloat in [-1.0,1.0] to GLbyte in [-128,127] */
  54 #define FLOAT_TO_BYTE(X)    ( (((GLint) (255.0F * (X))) - 1) / 2 )
  55
  56
  57 /** Convert GLbyte in [-128,127] to GLfloat in [-1.0,1.0], texture/fb data */
  58 #define BYTE_TO_FLOAT_TEX(B)    ((B) == -128 ? -1.0F : (B) * (1.0F/127.0F))
  59
  60 /** Convert GLfloat in [-1.0,1.0] to GLbyte in [-128,127], texture/fb data */
  61 #define FLOAT_TO_BYTE_TEX(X)    ( (GLint) (127.0F * (X)) )
  62
  63
  64 /** Convert GLushort in [0,65535] to GLfloat in [0.0,1.0] */
  65 #define USHORT_TO_FLOAT(S)  ((GLfloat) (S) * (1.0F / 65535.0F))
  66
  67 /** Convert GLfloat in [0.0,1.0] to GLushort in [0, 65535] */
  68 #define FLOAT_TO_USHORT(X)   ((GLuint) ((X) * 65535.0F))
  69
  70
  71 /** Convert GLshort in [-32768,32767] to GLfloat in [-1.0,1.0] */
  72 #define SHORT_TO_FLOAT(S)   ((2.0F * (S) + 1.0F) * (1.0F/65535.0F))
  73
  74 /** Convert GLfloat in [-1.0,1.0] to GLshort in [-32768,32767] */
  75 #define FLOAT_TO_SHORT(X)   ( (((GLint) (65535.0F * (X))) - 1) / 2 )
  76
  77
  78 /** Convert GLshort in [-32768,32767] to GLfloat in [-1.0,1.0], texture/fb data */
  79 #define SHORT_TO_FLOAT_TEX(S)    ((S) == -32768 ? -1.0F : (S) * (1.0F/32767.0F))
  80
  81 /** Convert GLfloat in [-1.0,1.0] to GLshort in [-32768,32767], texture/fb data */
  82 #define FLOAT_TO_SHORT_TEX(X)    ( (GLint) (32767.0F * (X)) )
  83
  84
  85 /** Convert GLuint in [0,4294967295] to GLfloat in [0.0,1.0] */
  86 #define UINT_TO_FLOAT(U)    ((GLfloat) (U) * (1.0F / 4294967295.0))
  87
  88 /** Convert GLfloat in [0.0,1.0] to GLuint in [0,4294967295] */
  89 #define FLOAT_TO_UINT(X)    ((GLuint) ((X) * 4294967295.0))
  90
  91
  92 /** Convert GLint in [-2147483648,2147483647] to GLfloat in [-1.0,1.0] */
  93 #define INT_TO_FLOAT(I)     ((2.0F * (I) + 1.0F) * (1.0F/4294967294.0))
  94
  95 /** Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647] */
  96 /* causes overflow:
  97 #define FLOAT_TO_INT(X)     ( (((GLint) (4294967294.0 * (X))) - 1) / 2 )
  98 */
  99 /* a close approximation: */
 100 #define FLOAT_TO_INT(X)     ( (GLint) (2147483647.0 * (X)) )
 101
 102 /** Convert GLfloat in [-1.0,1.0] to GLint64 in [-(1<<63),(1 << 63) -1] */
 103 #define FLOAT_TO_INT64(X)     ( (GLint64) (9223372036854775807.0 * (double)(X)) )
 104
 105
 106 /** Convert GLint in [-2147483648,2147483647] to GLfloat in [-1.0,1.0], texture/fb data */
 107 #define INT_TO_FLOAT_TEX(I)    ((I) == -2147483648 ? -1.0F : (I) * (1.0F/2147483647.0))
 108
 109 /** Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647], texture/fb data */
 110 #define FLOAT_TO_INT_TEX(X)    ( (GLint) (2147483647.0 * (X)) )
 111
 112
 113 #define BYTE_TO_UBYTE(b)   ((GLubyte) ((b) < 0 ? 0 : (GLubyte) (b)))
 114 #define SHORT_TO_UBYTE(s)  ((GLubyte) ((s) < 0 ? 0 : (GLubyte) ((s) >> 7)))
 115 #define USHORT_TO_UBYTE(s) ((GLubyte) ((s) >> 8))
 116 #define INT_TO_UBYTE(i)    ((GLubyte) ((i) < 0 ? 0 : (GLubyte) ((i) >> 23)))
 117 #define UINT_TO_UBYTE(i)   ((GLubyte) ((i) >> 24))
 118
 119
 120 #define BYTE_TO_USHORT(b)  ((b) < 0 ? 0 : ((GLushort) (((b) * 65535) / 255)))
 121 #define UBYTE_TO_USHORT(b) (((GLushort) (b) << 8) | (GLushort) (b))
 122 #define SHORT_TO_USHORT(s) ((s) < 0 ? 0 : ((GLushort) (((s) * 65535 / 32767))))
 123 #define INT_TO_USHORT(i)   ((i) < 0 ? 0 : ((GLushort) ((i) >> 15)))
 124 #define UINT_TO_USHORT(i)  ((i) < 0 ? 0 : ((GLushort) ((i) >> 16)))
 125 #define UNCLAMPED_FLOAT_TO_USHORT(us, f)  \
 126         us = ( (GLushort) IROUND( CLAMP((f), 0.0F, 1.0F) * 65535.0F) )
 127 #define CLAMPED_FLOAT_TO_USHORT(us, f)  \
 128         us = ( (GLushort) IROUND( (f) * 65535.0F) )
 129
 130 /*@}*/
 131
 132
 133 /** Stepping a GLfloat pointer by a byte stride */
 134 #define STRIDE_F(p, i)  (p = (GLfloat *)((GLubyte *)p + i))
 135 /** Stepping a GLuint pointer by a byte stride */
 136 #define STRIDE_UI(p, i)  (p = (GLuint *)((GLubyte *)p + i))
 137 /** Stepping a GLubyte[4] pointer by a byte stride */
 138 #define STRIDE_4UB(p, i)  (p = (GLubyte (*)[4])((GLubyte *)p + i))
 139 /** Stepping a GLfloat[4] pointer by a byte stride */
 140 #define STRIDE_4F(p, i)  (p = (GLfloat (*)[4])((GLubyte *)p + i))
 141 /** Stepping a GLchan[4] pointer by a byte stride */
 142 #define STRIDE_4CHAN(p, i)  (p = (GLchan (*)[4])((GLubyte *)p + i))
 143 /** Stepping a GLchan pointer by a byte stride */
 144 #define STRIDE_CHAN(p, i)  (p = (GLchan *)((GLubyte *)p + i))
 145 /** Stepping a \p t pointer by a byte stride */
 146 #define STRIDE_T(p, t, i)  (p = (t)((GLubyte *)p + i))
 147
 148
 149 /**********************************************************************/
 150 /** \name 4-element vector operations */
 151 /*@{*/
 152
 153 /** Zero */
 154 #define ZERO_4V( DST )  (DST)[0] = (DST)[1] = (DST)[2] = (DST)[3] = 0
 155
 156 /** Test for equality */
 157 #define TEST_EQ_4V(a,b)  ((a)[0] == (b)[0] &&   \
 158               (a)[1] == (b)[1] &&   \
 159               (a)[2] == (b)[2] &&   \
 160               (a)[3] == (b)[3])
 161
 162 /** Test for equality (unsigned bytes) */
 163 #if defined(__i386__)
 164 #define TEST_EQ_4UBV(DST, SRC) *((GLuint*)(DST)) == *((GLuint*)(SRC))
 165 #else
 166 #define TEST_EQ_4UBV(DST, SRC) TEST_EQ_4V(DST, SRC)
 167 #endif
 168
 169 /** Copy a 4-element vector */
 170 #define COPY_4V( DST, SRC )         \
 171 do {                                \
 172    (DST)[0] = (SRC)[0];             \
 173    (DST)[1] = (SRC)[1];             \
 174    (DST)[2] = (SRC)[2];             \
 175    (DST)[3] = (SRC)[3];             \
 176 } while (0)
 177
 178 /** Copy a 4-element vector with cast */
 179 #define COPY_4V_CAST( DST, SRC, CAST )  \
 180 do {                                    \
 181    (DST)[0] = (CAST)(SRC)[0];           \
 182    (DST)[1] = (CAST)(SRC)[1];           \
 183    (DST)[2] = (CAST)(SRC)[2];           \
 184    (DST)[3] = (CAST)(SRC)[3];           \
 185 } while (0)
 186
 187 /** Copy a 4-element unsigned byte vector */
 188 #if defined(__i386__)
 189 #define COPY_4UBV(DST, SRC)                 \
 190 do {                                        \
 191    *((GLuint*)(DST)) = *((GLuint*)(SRC));   \
 192 } while (0)
 193 #else
 194 /* The GLuint cast might fail if DST or SRC are not dword-aligned (RISC) */
 195 #define COPY_4UBV(DST, SRC)         \
 196 do {                                \
 197    (DST)[0] = (SRC)[0];             \
 198    (DST)[1] = (SRC)[1];             \
 199    (DST)[2] = (SRC)[2];             \
 200    (DST)[3] = (SRC)[3];             \
 201 } while (0)
 202 #endif
 203
 204 /**
 205  * Copy a 4-element float vector (avoid using FPU registers)
 206  * XXX Could use two 64-bit moves on 64-bit systems
 207  */
 208 #define COPY_4FV( DST, SRC )                  \
 209 do {                                          \
 210    const GLuint *_s = (const GLuint *) (SRC); \
 211    GLuint *_d = (GLuint *) (DST);             \
 212    _d[0] = _s[0];                             \
 213    _d[1] = _s[1];                             \
 214    _d[2] = _s[2];                             \
 215    _d[3] = _s[3];                             \
 216 } while (0)
 217
 218 /** Copy \p SZ elements into a 4-element vector */
 219 #define COPY_SZ_4V(DST, SZ, SRC)  \
 220 do {                              \
 221    switch (SZ) {                  \
 222    case 4: (DST)[3] = (SRC)[3];   \
 223    case 3: (DST)[2] = (SRC)[2];   \
 224    case 2: (DST)[1] = (SRC)[1];   \
 225    case 1: (DST)[0] = (SRC)[0];   \
 226    }                              \
 227 } while(0)
 228
 229 /** Copy \p SZ elements into a homegeneous (4-element) vector, giving
 230  * default values to the remaining */
 231 #define COPY_CLEAN_4V(DST, SZ, SRC)  \
 232 do {                                 \
 233       ASSIGN_4V( DST, 0, 0, 0, 1 );  \
 234       COPY_SZ_4V( DST, SZ, SRC );    \
 235 } while (0)
 236
 237 /** Subtraction */
 238 #define SUB_4V( DST, SRCA, SRCB )           \
 239 do {                                        \
 240       (DST)[0] = (SRCA)[0] - (SRCB)[0];     \
 241       (DST)[1] = (SRCA)[1] - (SRCB)[1];     \
 242       (DST)[2] = (SRCA)[2] - (SRCB)[2];     \
 243       (DST)[3] = (SRCA)[3] - (SRCB)[3];     \
 244 } while (0)
 245
 246 /** Addition */
 247 #define ADD_4V( DST, SRCA, SRCB )           \
 248 do {                                        \
 249       (DST)[0] = (SRCA)[0] + (SRCB)[0];     \
 250       (DST)[1] = (SRCA)[1] + (SRCB)[1];     \
 251       (DST)[2] = (SRCA)[2] + (SRCB)[2];     \
 252       (DST)[3] = (SRCA)[3] + (SRCB)[3];     \
 253 } while (0)
 254
 255 /** Element-wise multiplication */
 256 #define SCALE_4V( DST, SRCA, SRCB )         \
 257 do {                                        \
 258       (DST)[0] = (SRCA)[0] * (SRCB)[0];     \
 259       (DST)[1] = (SRCA)[1] * (SRCB)[1];     \
 260       (DST)[2] = (SRCA)[2] * (SRCB)[2];     \
 261       (DST)[3] = (SRCA)[3] * (SRCB)[3];     \
 262 } while (0)
 263
 264 /** In-place addition */
 265 #define ACC_4V( DST, SRC )          \
 266 do {                                \
 267       (DST)[0] += (SRC)[0];         \
 268       (DST)[1] += (SRC)[1];         \
 269       (DST)[2] += (SRC)[2];         \
 270       (DST)[3] += (SRC)[3];         \
 271 } while (0)
 272
 273 /** Element-wise multiplication and addition */
 274 #define ACC_SCALE_4V( DST, SRCA, SRCB )     \
 275 do {                                        \
 276       (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
 277       (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
 278       (DST)[2] += (SRCA)[2] * (SRCB)[2];    \
 279       (DST)[3] += (SRCA)[3] * (SRCB)[3];    \
 280 } while (0)
 281
 282 /** In-place scalar multiplication and addition */
 283 #define ACC_SCALE_SCALAR_4V( DST, S, SRCB ) \
 284 do {                                        \
 285       (DST)[0] += S * (SRCB)[0];            \
 286       (DST)[1] += S * (SRCB)[1];            \
 287       (DST)[2] += S * (SRCB)[2];            \
 288       (DST)[3] += S * (SRCB)[3];            \
 289 } while (0)
 290
 291 /** Scalar multiplication */
 292 #define SCALE_SCALAR_4V( DST, S, SRCB ) \
 293 do {                                    \
 294       (DST)[0] = S * (SRCB)[0];         \
 295       (DST)[1] = S * (SRCB)[1];         \
 296       (DST)[2] = S * (SRCB)[2];         \
 297       (DST)[3] = S * (SRCB)[3];         \
 298 } while (0)
 299
 300 /** In-place scalar multiplication */
 301 #define SELF_SCALE_SCALAR_4V( DST, S ) \
 302 do {                                   \
 303       (DST)[0] *= S;                   \
 304       (DST)[1] *= S;                   \
 305       (DST)[2] *= S;                   \
 306       (DST)[3] *= S;                   \
 307 } while (0)
 308
 309 /** Assignment */
 310 #define ASSIGN_4V( V, V0, V1, V2, V3 )  \
 311 do {                                    \
 312     V[0] = V0;                          \
 313     V[1] = V1;                          \
 314     V[2] = V2;                          \
 315     V[3] = V3;                          \
 316 } while(0)
 317
 318 /*@}*/
 319
 320
 321 /**********************************************************************/
 322 /** \name 3-element vector operations*/
 323 /*@{*/
 324
 325 /** Zero */
 326 #define ZERO_3V( DST )  (DST)[0] = (DST)[1] = (DST)[2] = 0
 327
 328 /** Test for equality */
 329 #define TEST_EQ_3V(a,b)  \
 330    ((a)[0] == (b)[0] &&  \
 331     (a)[1] == (b)[1] &&  \
 332     (a)[2] == (b)[2])
 333
 334 /** Copy a 3-element vector */
 335 #define COPY_3V( DST, SRC )         \
 336 do {                                \
 337    (DST)[0] = (SRC)[0];             \
 338    (DST)[1] = (SRC)[1];             \
 339    (DST)[2] = (SRC)[2];             \
 340 } while (0)
 341
 342 /** Copy a 3-element vector with cast */
 343 #define COPY_3V_CAST( DST, SRC, CAST )  \
 344 do {                                    \
 345    (DST)[0] = (CAST)(SRC)[0];           \
 346    (DST)[1] = (CAST)(SRC)[1];           \
 347    (DST)[2] = (CAST)(SRC)[2];           \
 348 } while (0)
 349
 350 /** Copy a 3-element float vector */
 351 #define COPY_3FV( DST, SRC )        \
 352 do {                                \
 353    const GLfloat *_tmp = (SRC);     \
 354    (DST)[0] = _tmp[0];              \
 355    (DST)[1] = _tmp[1];              \
 356    (DST)[2] = _tmp[2];              \
 357 } while (0)
 358
 359 /** Subtraction */
 360 #define SUB_3V( DST, SRCA, SRCB )        \
 361 do {                                     \
 362       (DST)[0] = (SRCA)[0] - (SRCB)[0];  \
 363       (DST)[1] = (SRCA)[1] - (SRCB)[1];  \
 364       (DST)[2] = (SRCA)[2] - (SRCB)[2];  \
 365 } while (0)
 366
 367 /** Addition */
 368 #define ADD_3V( DST, SRCA, SRCB )       \
 369 do {                                    \
 370       (DST)[0] = (SRCA)[0] + (SRCB)[0]; \
 371       (DST)[1] = (SRCA)[1] + (SRCB)[1]; \
 372       (DST)[2] = (SRCA)[2] + (SRCB)[2]; \
 373 } while (0)
 374
 375 /** In-place scalar multiplication */
 376 #define SCALE_3V( DST, SRCA, SRCB )     \
 377 do {                                    \
 378       (DST)[0] = (SRCA)[0] * (SRCB)[0]; \
 379       (DST)[1] = (SRCA)[1] * (SRCB)[1]; \
 380       (DST)[2] = (SRCA)[2] * (SRCB)[2]; \
 381 } while (0)
 382
 383 /** In-place element-wise multiplication */
 384 #define SELF_SCALE_3V( DST, SRC )   \
 385 do {                                \
 386       (DST)[0] *= (SRC)[0];         \
 387       (DST)[1] *= (SRC)[1];         \
 388       (DST)[2] *= (SRC)[2];         \
 389 } while (0)
 390
 391 /** In-place addition */
 392 #define ACC_3V( DST, SRC )          \
 393 do {                                \
 394       (DST)[0] += (SRC)[0];         \
 395       (DST)[1] += (SRC)[1];         \
 396       (DST)[2] += (SRC)[2];         \
 397 } while (0)
 398
 399 /** Element-wise multiplication and addition */
 400 #define ACC_SCALE_3V( DST, SRCA, SRCB )     \
 401 do {                                        \
 402       (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
 403       (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
 404       (DST)[2] += (SRCA)[2] * (SRCB)[2];    \
 405 } while (0)
 406
 407 /** Scalar multiplication */
 408 #define SCALE_SCALAR_3V( DST, S, SRCB ) \
 409 do {                                    \
 410       (DST)[0] = S * (SRCB)[0];         \
 411       (DST)[1] = S * (SRCB)[1];         \
 412       (DST)[2] = S * (SRCB)[2];         \
 413 } while (0)
 414
 415 /** In-place scalar multiplication and addition */
 416 #define ACC_SCALE_SCALAR_3V( DST, S, SRCB ) \
 417 do {                                        \
 418       (DST)[0] += S * (SRCB)[0];            \
 419       (DST)[1] += S * (SRCB)[1];            \
 420       (DST)[2] += S * (SRCB)[2];            \
 421 } while (0)
 422
 423 /** In-place scalar multiplication */
 424 #define SELF_SCALE_SCALAR_3V( DST, S ) \
 425 do {                                   \
 426       (DST)[0] *= S;                   \
 427       (DST)[1] *= S;                   \
 428       (DST)[2] *= S;                   \
 429 } while (0)
 430
 431 /** In-place scalar addition */
 432 #define ACC_SCALAR_3V( DST, S )     \
 433 do {                                \
 434       (DST)[0] += S;                \
 435       (DST)[1] += S;                \
 436       (DST)[2] += S;                \
 437 } while (0)
 438
 439 /** Assignment */
 440 #define ASSIGN_3V( V, V0, V1, V2 )  \
 441 do {                                \
 442     V[0] = V0;                      \
 443     V[1] = V1;                      \
 444     V[2] = V2;                      \
 445 } while(0)
 446
 447 /*@}*/
 448
 449
 450 /**********************************************************************/
 451 /** \name 2-element vector operations*/
 452 /*@{*/
 453
 454 /** Zero */
 455 #define ZERO_2V( DST )  (DST)[0] = (DST)[1] = 0
 456
 457 /** Copy a 2-element vector */
 458 #define COPY_2V( DST, SRC )         \
 459 do {                        \
 460    (DST)[0] = (SRC)[0];             \
 461    (DST)[1] = (SRC)[1];             \
 462 } while (0)
 463
 464 /** Copy a 2-element vector with cast */
 465 #define COPY_2V_CAST( DST, SRC, CAST )      \
 466 do {                        \
 467    (DST)[0] = (CAST)(SRC)[0];           \
 468    (DST)[1] = (CAST)(SRC)[1];           \
 469 } while (0)
 470
 471 /** Copy a 2-element float vector */
 472 #define COPY_2FV( DST, SRC )            \
 473 do {                        \
 474    const GLfloat *_tmp = (SRC);         \
 475    (DST)[0] = _tmp[0];              \
 476    (DST)[1] = _tmp[1];              \
 477 } while (0)
 478
 479 /** Subtraction */
 480 #define SUB_2V( DST, SRCA, SRCB )       \
 481 do {                        \
 482       (DST)[0] = (SRCA)[0] - (SRCB)[0];     \
 483       (DST)[1] = (SRCA)[1] - (SRCB)[1];     \
 484 } while (0)
 485
 486 /** Addition */
 487 #define ADD_2V( DST, SRCA, SRCB )       \
 488 do {                        \
 489       (DST)[0] = (SRCA)[0] + (SRCB)[0];     \
 490       (DST)[1] = (SRCA)[1] + (SRCB)[1];     \
 491 } while (0)
 492
 493 /** In-place scalar multiplication */
 494 #define SCALE_2V( DST, SRCA, SRCB )     \
 495 do {                        \
 496       (DST)[0] = (SRCA)[0] * (SRCB)[0];     \
 497       (DST)[1] = (SRCA)[1] * (SRCB)[1];     \
 498 } while (0)
 499
 500 /** In-place addition */
 501 #define ACC_2V( DST, SRC )          \
 502 do {                        \
 503       (DST)[0] += (SRC)[0];         \
 504       (DST)[1] += (SRC)[1];         \
 505 } while (0)
 506
 507 /** Element-wise multiplication and addition */
 508 #define ACC_SCALE_2V( DST, SRCA, SRCB )     \
 509 do {                        \
 510       (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
 511       (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
 512 } while (0)
 513
 514 /** Scalar multiplication */
 515 #define SCALE_SCALAR_2V( DST, S, SRCB )     \
 516 do {                        \
 517       (DST)[0] = S * (SRCB)[0];         \
 518       (DST)[1] = S * (SRCB)[1];         \
 519 } while (0)
 520
 521 /** In-place scalar multiplication and addition */
 522 #define ACC_SCALE_SCALAR_2V( DST, S, SRCB ) \
 523 do {                        \
 524       (DST)[0] += S * (SRCB)[0];        \
 525       (DST)[1] += S * (SRCB)[1];        \
 526 } while (0)
 527
 528 /** In-place scalar multiplication */
 529 #define SELF_SCALE_SCALAR_2V( DST, S )      \
 530 do {                        \
 531       (DST)[0] *= S;                \
 532       (DST)[1] *= S;                \
 533 } while (0)
 534
 535 /** In-place scalar addition */
 536 #define ACC_SCALAR_2V( DST, S )         \
 537 do {                        \
 538       (DST)[0] += S;                \
 539       (DST)[1] += S;                \
 540 } while (0)
 541
 542 /** Assign scalers to short vectors */
 543 #define ASSIGN_2V( V, V0, V1 )  \
 544 do {                            \
 545     V[0] = V0;                  \
 546     V[1] = V1;                  \
 547 } while(0)
 548
 549 /*@}*/
 550
 551
 552 /** \name Linear interpolation macros */
 553 /*@{*/
 554
 555 /**
 556  * Linear interpolation
 557  *
 558  * \note \p OUT argument is evaluated twice!
 559  * \note Be wary of using *coord++ as an argument to any of these macros!
 560  */
 561 #define LINTERP(T, OUT, IN) ((OUT) + (T) * ((IN) - (OUT)))
 562
 563 /* Can do better with integer math
 564  */
 565 #define INTERP_UB( t, dstub, outub, inub )  \
 566 do {                        \
 567    GLfloat inf = UBYTE_TO_FLOAT( inub );    \
 568    GLfloat outf = UBYTE_TO_FLOAT( outub );  \
 569    GLfloat dstf = LINTERP( t, outf, inf );  \
 570    UNCLAMPED_FLOAT_TO_UBYTE( dstub, dstf ); \
 571 } while (0)
 572
 573 #define INTERP_CHAN( t, dstc, outc, inc )   \
 574 do {                        \
 575    GLfloat inf = CHAN_TO_FLOAT( inc );      \
 576    GLfloat outf = CHAN_TO_FLOAT( outc );    \
 577    GLfloat dstf = LINTERP( t, outf, inf );  \
 578    UNCLAMPED_FLOAT_TO_CHAN( dstc, dstf );   \
 579 } while (0)
 580
 581 #define INTERP_UI( t, dstui, outui, inui )  \
 582    dstui = (GLuint) (GLint) LINTERP( (t), (GLfloat) (outui), (GLfloat) (inui) )
 583
 584 #define INTERP_F( t, dstf, outf, inf )      \
 585    dstf = LINTERP( t, outf, inf )
 586
 587 #define INTERP_4F( t, dst, out, in )        \
 588 do {                        \
 589    dst[0] = LINTERP( (t), (out)[0], (in)[0] );  \
 590    dst[1] = LINTERP( (t), (out)[1], (in)[1] );  \
 591    dst[2] = LINTERP( (t), (out)[2], (in)[2] );  \
 592    dst[3] = LINTERP( (t), (out)[3], (in)[3] );  \
 593 } while (0)
 594
 595 #define INTERP_3F( t, dst, out, in )        \
 596 do {                        \
 597    dst[0] = LINTERP( (t), (out)[0], (in)[0] );  \
 598    dst[1] = LINTERP( (t), (out)[1], (in)[1] );  \
 599    dst[2] = LINTERP( (t), (out)[2], (in)[2] );  \
 600 } while (0)
 601
 602 #define INTERP_4CHAN( t, dst, out, in )         \
 603 do {                            \
 604    INTERP_CHAN( (t), (dst)[0], (out)[0], (in)[0] ); \
 605    INTERP_CHAN( (t), (dst)[1], (out)[1], (in)[1] ); \
 606    INTERP_CHAN( (t), (dst)[2], (out)[2], (in)[2] ); \
 607    INTERP_CHAN( (t), (dst)[3], (out)[3], (in)[3] ); \
 608 } while (0)
 609
 610 #define INTERP_3CHAN( t, dst, out, in )         \
 611 do {                            \
 612    INTERP_CHAN( (t), (dst)[0], (out)[0], (in)[0] ); \
 613    INTERP_CHAN( (t), (dst)[1], (out)[1], (in)[1] ); \
 614    INTERP_CHAN( (t), (dst)[2], (out)[2], (in)[2] ); \
 615 } while (0)
 616
 617 #define INTERP_SZ( t, vec, to, out, in, sz )                \
 618 do {                                    \
 619    switch (sz) {                            \
 620    case 4: vec[to][3] = LINTERP( (t), (vec)[out][3], (vec)[in][3] );    \
 621    case 3: vec[to][2] = LINTERP( (t), (vec)[out][2], (vec)[in][2] );    \
 622    case 2: vec[to][1] = LINTERP( (t), (vec)[out][1], (vec)[in][1] );    \
 623    case 1: vec[to][0] = LINTERP( (t), (vec)[out][0], (vec)[in][0] );    \
 624    }                                    \
 625 } while(0)
 626
 627 /*@}*/
 628
 629
 630
 631 /** Clamp X to [MIN,MAX] */
 632 #define CLAMP( X, MIN, MAX )  ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
 633
 634 /** Assign X to CLAMP(X, MIN, MAX) */
 635 #define CLAMP_SELF(x, mn, mx)  \
 636    ( (x)<(mn) ? ((x) = (mn)) : ((x)>(mx) ? ((x)=(mx)) : (x)) )
 637
 638
 639
 640 /** Minimum of two values: */
 641 #define MIN2( A, B )   ( (A)<(B) ? (A) : (B) )
 642
 643 /** Maximum of two values: */
 644 #define MAX2( A, B )   ( (A)>(B) ? (A) : (B) )
 645
 646 /** Dot product of two 2-element vectors */
 647 #define DOT2( a, b )  ( (a)[0]*(b)[0] + (a)[1]*(b)[1] )
 648
 649 /** Dot product of two 3-element vectors */
 650 #define DOT3( a, b )  ( (a)[0]*(b)[0] + (a)[1]*(b)[1] + (a)[2]*(b)[2] )
 651
 652 /** Dot product of two 4-element vectors */
 653 #define DOT4( a, b )  ( (a)[0]*(b)[0] + (a)[1]*(b)[1] + \
 654             (a)[2]*(b)[2] + (a)[3]*(b)[3] )
 655
 656 /** Dot product of two 4-element vectors */
 657 #define DOT4V(v,a,b,c,d) (v[0]*(a) + v[1]*(b) + v[2]*(c) + v[3]*(d))
 658
 659
 660 /** Cross product of two 3-element vectors */
 661 #define CROSS3(n, u, v)             \
 662 do {                        \
 663    (n)[0] = (u)[1]*(v)[2] - (u)[2]*(v)[1];  \
 664    (n)[1] = (u)[2]*(v)[0] - (u)[0]*(v)[2];  \
 665    (n)[2] = (u)[0]*(v)[1] - (u)[1]*(v)[0];  \
 666 } while (0)
 667
 668
 669 /* Normalize a 3-element vector to unit length. */
 670 #define NORMALIZE_3FV( V )          \
 671 do {                        \
 672    GLfloat len = (GLfloat) LEN_SQUARED_3FV(V);  \
 673    if (len) {                   \
 674       len = INV_SQRTF(len);         \
 675       (V)[0] = (GLfloat) ((V)[0] * len);    \
 676       (V)[1] = (GLfloat) ((V)[1] * len);    \
 677       (V)[2] = (GLfloat) ((V)[2] * len);    \
 678    }                        \
 679 } while(0)
 680
 681 #define LEN_3FV( V ) (SQRTF((V)[0]*(V)[0]+(V)[1]*(V)[1]+(V)[2]*(V)[2]))
 682 #define LEN_2FV( V ) (SQRTF((V)[0]*(V)[0]+(V)[1]*(V)[1]))
 683
 684 #define LEN_SQUARED_3FV( V ) ((V)[0]*(V)[0]+(V)[1]*(V)[1]+(V)[2]*(V)[2])
 685 #define LEN_SQUARED_2FV( V ) ((V)[0]*(V)[0]+(V)[1]*(V)[1])
 686
 687
 688 /** casts to silence warnings with some compilers */
 689 #define ENUM_TO_INT(E)     ((GLint)(E))
 690 #define ENUM_TO_FLOAT(E)   ((GLfloat)(GLint)(E))
 691 #define ENUM_TO_DOUBLE(E)  ((GLdouble)(GLint)(E))
 692 #define ENUM_TO_BOOLEAN(E) ((E) ? GL_TRUE : GL_FALSE)
 693
 694
 695 #endif