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 GLushort in [0,65536] to GLfloat in [0.0,1.0] */
  58 #define USHORT_TO_FLOAT(S)  ((GLfloat) (S) * (1.0F / 65535.0F))
  59
  60 /** Convert GLshort in [-32768,32767] to GLfloat in [-1.0,1.0] */
  61 #define SHORT_TO_FLOAT(S)   ((2.0F * (S) + 1.0F) * (1.0F/65535.0F))
  62
  63 /** Convert GLfloat in [0.0,1.0] to GLshort in [-32768,32767] */
  64 #define FLOAT_TO_SHORT(X)   ( (((GLint) (65535.0F * (X))) - 1) / 2 )
  65
  66
  67 /** Convert GLuint in [0,4294967295] to GLfloat in [0.0,1.0] */
  68 #define UINT_TO_FLOAT(U)    ((GLfloat) (U) * (1.0F / 4294967295.0F))
  69
  70 /** Convert GLfloat in [0.0,1.0] to GLuint in [0,4294967295] */
  71 #define FLOAT_TO_UINT(X)    ((GLuint) ((X) * 4294967295.0))
  72
  73
  74 /** Convert GLint in [-2147483648,2147483647] to GLfloat in [-1.0,1.0] */
  75 #define INT_TO_FLOAT(I)     ((2.0F * (I) + 1.0F) * (1.0F/4294967294.0F))
  76
  77 /** Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647] */
  78 /* causes overflow:
  79 #define FLOAT_TO_INT(X)     ( (((GLint) (4294967294.0F * (X))) - 1) / 2 )
  80 */
  81 /* a close approximation: */
  82 #define FLOAT_TO_INT(X)     ( (GLint) (2147483647.0 * (X)) )
  83
  84
  85 #define BYTE_TO_UBYTE(b)   ((GLubyte) ((b) < 0 ? 0 : (GLubyte) (b)))
  86 #define SHORT_TO_UBYTE(s)  ((GLubyte) ((s) < 0 ? 0 : (GLubyte) ((s) >> 7)))
  87 #define USHORT_TO_UBYTE(s) ((GLubyte) ((s) >> 8))
  88 #define INT_TO_UBYTE(i)    ((GLubyte) ((i) < 0 ? 0 : (GLubyte) ((i) >> 23)))
  89 #define UINT_TO_UBYTE(i)   ((GLubyte) ((i) >> 24))
  90
  91
  92 #define BYTE_TO_USHORT(b)  ((b) < 0 ? 0 : ((GLushort) (((b) * 65535) / 255)))
  93 #define UBYTE_TO_USHORT(b) (((GLushort) (b) << 8) | (GLushort) (b))
  94 #define SHORT_TO_USHORT(s) ((s) < 0 ? 0 : ((GLushort) (((s) * 65535 / 32767))))
  95 #define INT_TO_USHORT(i)   ((i) < 0 ? 0 : ((GLushort) ((i) >> 15)))
  96 #define UINT_TO_USHORT(i)  ((i) < 0 ? 0 : ((GLushort) ((i) >> 16)))
  97 #define UNCLAMPED_FLOAT_TO_USHORT(us, f)  \
  98         us = ( (GLushort) IROUND( CLAMP((f), 0.0, 1.0) * 65535.0F) )
  99 #define CLAMPED_FLOAT_TO_USHORT(us, f)  \
 100         us = ( (GLushort) IROUND( (f) * 65535.0F) )
 101
 102 /*@}*/
 103
 104
 105 /** Stepping a GLfloat pointer by a byte stride */
 106 #define STRIDE_F(p, i)  (p = (GLfloat *)((GLubyte *)p + i))
 107 /** Stepping a GLuint pointer by a byte stride */
 108 #define STRIDE_UI(p, i)  (p = (GLuint *)((GLubyte *)p + i))
 109 /** Stepping a GLubyte[4] pointer by a byte stride */
 110 #define STRIDE_4UB(p, i)  (p = (GLubyte (*)[4])((GLubyte *)p + i))
 111 /** Stepping a GLfloat[4] pointer by a byte stride */
 112 #define STRIDE_4F(p, i)  (p = (GLfloat (*)[4])((GLubyte *)p + i))
 113 /** Stepping a GLchan[4] pointer by a byte stride */
 114 #define STRIDE_4CHAN(p, i)  (p = (GLchan (*)[4])((GLubyte *)p + i))
 115 /** Stepping a GLchan pointer by a byte stride */
 116 #define STRIDE_CHAN(p, i)  (p = (GLchan *)((GLubyte *)p + i))
 117 /** Stepping a \p t pointer by a byte stride */
 118 #define STRIDE_T(p, t, i)  (p = (t)((GLubyte *)p + i))
 119
 120
 121 /**********************************************************************/
 122 /** \name 4-element vector operations */
 123 /*@{*/
 124
 125 /** Zero */
 126 #define ZERO_4V( DST )  (DST)[0] = (DST)[1] = (DST)[2] = (DST)[3] = 0
 127
 128 /** Test for equality */
 129 #define TEST_EQ_4V(a,b)  ((a)[0] == (b)[0] &&   \
 130               (a)[1] == (b)[1] &&   \
 131               (a)[2] == (b)[2] &&   \
 132               (a)[3] == (b)[3])
 133
 134 /** Test for equality (unsigned bytes) */
 135 #if defined(__i386__)
 136 #define TEST_EQ_4UBV(DST, SRC) *((GLuint*)(DST)) == *((GLuint*)(SRC))
 137 #else
 138 #define TEST_EQ_4UBV(DST, SRC) TEST_EQ_4V(DST, SRC)
 139 #endif
 140
 141 /** Copy a 4-element vector */
 142 #define COPY_4V( DST, SRC )         \
 143 do {                                \
 144    (DST)[0] = (SRC)[0];             \
 145    (DST)[1] = (SRC)[1];             \
 146    (DST)[2] = (SRC)[2];             \
 147    (DST)[3] = (SRC)[3];             \
 148 } while (0)
 149
 150 /** Copy a 4-element vector with cast */
 151 #define COPY_4V_CAST( DST, SRC, CAST )  \
 152 do {                                    \
 153    (DST)[0] = (CAST)(SRC)[0];           \
 154    (DST)[1] = (CAST)(SRC)[1];           \
 155    (DST)[2] = (CAST)(SRC)[2];           \
 156    (DST)[3] = (CAST)(SRC)[3];           \
 157 } while (0)
 158
 159 /** Copy a 4-element unsigned byte vector */
 160 #if defined(__i386__)
 161 #define COPY_4UBV(DST, SRC)                 \
 162 do {                                        \
 163    *((GLuint*)(DST)) = *((GLuint*)(SRC));   \
 164 } while (0)
 165 #else
 166 /* The GLuint cast might fail if DST or SRC are not dword-aligned (RISC) */
 167 #define COPY_4UBV(DST, SRC)         \
 168 do {                                \
 169    (DST)[0] = (SRC)[0];             \
 170    (DST)[1] = (SRC)[1];             \
 171    (DST)[2] = (SRC)[2];             \
 172    (DST)[3] = (SRC)[3];             \
 173 } while (0)
 174 #endif
 175
 176 /**
 177  * Copy a 4-element float vector (avoid using FPU registers)
 178  * XXX Could use two 64-bit moves on 64-bit systems
 179  */
 180 #define COPY_4FV( DST, SRC )                  \
 181 do {                                          \
 182    const GLuint *_s = (const GLuint *) (SRC); \
 183    GLuint *_d = (GLuint *) (DST);             \
 184    _d[0] = _s[0];                             \
 185    _d[1] = _s[1];                             \
 186    _d[2] = _s[2];                             \
 187    _d[3] = _s[3];                             \
 188 } while (0)
 189
 190 /** Copy \p SZ elements into a 4-element vector */
 191 #define COPY_SZ_4V(DST, SZ, SRC)  \
 192 do {                              \
 193    switch (SZ) {                  \
 194    case 4: (DST)[3] = (SRC)[3];   \
 195    case 3: (DST)[2] = (SRC)[2];   \
 196    case 2: (DST)[1] = (SRC)[1];   \
 197    case 1: (DST)[0] = (SRC)[0];   \
 198    }                              \
 199 } while(0)
 200
 201 /** Copy \p SZ elements into a homegeneous (4-element) vector, giving
 202  * default values to the remaining */
 203 #define COPY_CLEAN_4V(DST, SZ, SRC)  \
 204 do {                                 \
 205       ASSIGN_4V( DST, 0, 0, 0, 1 );  \
 206       COPY_SZ_4V( DST, SZ, SRC );    \
 207 } while (0)
 208
 209 /** Subtraction */
 210 #define SUB_4V( DST, SRCA, SRCB )           \
 211 do {                                        \
 212       (DST)[0] = (SRCA)[0] - (SRCB)[0];     \
 213       (DST)[1] = (SRCA)[1] - (SRCB)[1];     \
 214       (DST)[2] = (SRCA)[2] - (SRCB)[2];     \
 215       (DST)[3] = (SRCA)[3] - (SRCB)[3];     \
 216 } while (0)
 217
 218 /** Addition */
 219 #define ADD_4V( DST, SRCA, SRCB )           \
 220 do {                                        \
 221       (DST)[0] = (SRCA)[0] + (SRCB)[0];     \
 222       (DST)[1] = (SRCA)[1] + (SRCB)[1];     \
 223       (DST)[2] = (SRCA)[2] + (SRCB)[2];     \
 224       (DST)[3] = (SRCA)[3] + (SRCB)[3];     \
 225 } while (0)
 226
 227 /** Element-wise multiplication */
 228 #define SCALE_4V( DST, SRCA, SRCB )         \
 229 do {                                        \
 230       (DST)[0] = (SRCA)[0] * (SRCB)[0];     \
 231       (DST)[1] = (SRCA)[1] * (SRCB)[1];     \
 232       (DST)[2] = (SRCA)[2] * (SRCB)[2];     \
 233       (DST)[3] = (SRCA)[3] * (SRCB)[3];     \
 234 } while (0)
 235
 236 /** In-place addition */
 237 #define ACC_4V( DST, SRC )          \
 238 do {                                \
 239       (DST)[0] += (SRC)[0];         \
 240       (DST)[1] += (SRC)[1];         \
 241       (DST)[2] += (SRC)[2];         \
 242       (DST)[3] += (SRC)[3];         \
 243 } while (0)
 244
 245 /** Element-wise multiplication and addition */
 246 #define ACC_SCALE_4V( DST, SRCA, SRCB )     \
 247 do {                                        \
 248       (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
 249       (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
 250       (DST)[2] += (SRCA)[2] * (SRCB)[2];    \
 251       (DST)[3] += (SRCA)[3] * (SRCB)[3];    \
 252 } while (0)
 253
 254 /** In-place scalar multiplication and addition */
 255 #define ACC_SCALE_SCALAR_4V( DST, S, SRCB ) \
 256 do {                                        \
 257       (DST)[0] += S * (SRCB)[0];            \
 258       (DST)[1] += S * (SRCB)[1];            \
 259       (DST)[2] += S * (SRCB)[2];            \
 260       (DST)[3] += S * (SRCB)[3];            \
 261 } while (0)
 262
 263 /** Scalar multiplication */
 264 #define SCALE_SCALAR_4V( DST, S, SRCB ) \
 265 do {                                    \
 266       (DST)[0] = S * (SRCB)[0];         \
 267       (DST)[1] = S * (SRCB)[1];         \
 268       (DST)[2] = S * (SRCB)[2];         \
 269       (DST)[3] = S * (SRCB)[3];         \
 270 } while (0)
 271
 272 /** In-place scalar multiplication */
 273 #define SELF_SCALE_SCALAR_4V( DST, S ) \
 274 do {                                   \
 275       (DST)[0] *= S;                   \
 276       (DST)[1] *= S;                   \
 277       (DST)[2] *= S;                   \
 278       (DST)[3] *= S;                   \
 279 } while (0)
 280
 281 /** Assignment */
 282 #define ASSIGN_4V( V, V0, V1, V2, V3 )  \
 283 do {                                    \
 284     V[0] = V0;                          \
 285     V[1] = V1;                          \
 286     V[2] = V2;                          \
 287     V[3] = V3;                          \
 288 } while(0)
 289
 290 /*@}*/
 291
 292
 293 /**********************************************************************/
 294 /** \name 3-element vector operations*/
 295 /*@{*/
 296
 297 /** Zero */
 298 #define ZERO_3V( DST )  (DST)[0] = (DST)[1] = (DST)[2] = 0
 299
 300 /** Test for equality */
 301 #define TEST_EQ_3V(a,b)  \
 302    ((a)[0] == (b)[0] &&  \
 303     (a)[1] == (b)[1] &&  \
 304     (a)[2] == (b)[2])
 305
 306 /** Copy a 3-element vector */
 307 #define COPY_3V( DST, SRC )         \
 308 do {                                \
 309    (DST)[0] = (SRC)[0];             \
 310    (DST)[1] = (SRC)[1];             \
 311    (DST)[2] = (SRC)[2];             \
 312 } while (0)
 313
 314 /** Copy a 3-element vector with cast */
 315 #define COPY_3V_CAST( DST, SRC, CAST )  \
 316 do {                                    \
 317    (DST)[0] = (CAST)(SRC)[0];           \
 318    (DST)[1] = (CAST)(SRC)[1];           \
 319    (DST)[2] = (CAST)(SRC)[2];           \
 320 } while (0)
 321
 322 /** Copy a 3-element float vector */
 323 #define COPY_3FV( DST, SRC )        \
 324 do {                                \
 325    const GLfloat *_tmp = (SRC);     \
 326    (DST)[0] = _tmp[0];              \
 327    (DST)[1] = _tmp[1];              \
 328    (DST)[2] = _tmp[2];              \
 329 } while (0)
 330
 331 /** Subtraction */
 332 #define SUB_3V( DST, SRCA, SRCB )        \
 333 do {                                     \
 334       (DST)[0] = (SRCA)[0] - (SRCB)[0];  \
 335       (DST)[1] = (SRCA)[1] - (SRCB)[1];  \
 336       (DST)[2] = (SRCA)[2] - (SRCB)[2];  \
 337 } while (0)
 338
 339 /** Addition */
 340 #define ADD_3V( DST, SRCA, SRCB )       \
 341 do {                                    \
 342       (DST)[0] = (SRCA)[0] + (SRCB)[0]; \
 343       (DST)[1] = (SRCA)[1] + (SRCB)[1]; \
 344       (DST)[2] = (SRCA)[2] + (SRCB)[2]; \
 345 } while (0)
 346
 347 /** In-place scalar multiplication */
 348 #define SCALE_3V( DST, SRCA, SRCB )     \
 349 do {                                    \
 350       (DST)[0] = (SRCA)[0] * (SRCB)[0]; \
 351       (DST)[1] = (SRCA)[1] * (SRCB)[1]; \
 352       (DST)[2] = (SRCA)[2] * (SRCB)[2]; \
 353 } while (0)
 354
 355 /** In-place element-wise multiplication */
 356 #define SELF_SCALE_3V( DST, SRC )   \
 357 do {                                \
 358       (DST)[0] *= (SRC)[0];         \
 359       (DST)[1] *= (SRC)[1];         \
 360       (DST)[2] *= (SRC)[2];         \
 361 } while (0)
 362
 363 /** In-place addition */
 364 #define ACC_3V( DST, SRC )          \
 365 do {                                \
 366       (DST)[0] += (SRC)[0];         \
 367       (DST)[1] += (SRC)[1];         \
 368       (DST)[2] += (SRC)[2];         \
 369 } while (0)
 370
 371 /** Element-wise multiplication and addition */
 372 #define ACC_SCALE_3V( DST, SRCA, SRCB )     \
 373 do {                                        \
 374       (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
 375       (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
 376       (DST)[2] += (SRCA)[2] * (SRCB)[2];    \
 377 } while (0)
 378
 379 /** Scalar multiplication */
 380 #define SCALE_SCALAR_3V( DST, S, SRCB ) \
 381 do {                                    \
 382       (DST)[0] = S * (SRCB)[0];         \
 383       (DST)[1] = S * (SRCB)[1];         \
 384       (DST)[2] = S * (SRCB)[2];         \
 385 } while (0)
 386
 387 /** In-place scalar multiplication and addition */
 388 #define ACC_SCALE_SCALAR_3V( DST, S, SRCB ) \
 389 do {                                        \
 390       (DST)[0] += S * (SRCB)[0];            \
 391       (DST)[1] += S * (SRCB)[1];            \
 392       (DST)[2] += S * (SRCB)[2];            \
 393 } while (0)
 394
 395 /** In-place scalar multiplication */
 396 #define SELF_SCALE_SCALAR_3V( DST, S ) \
 397 do {                                   \
 398       (DST)[0] *= S;                   \
 399       (DST)[1] *= S;                   \
 400       (DST)[2] *= S;                   \
 401 } while (0)
 402
 403 /** In-place scalar addition */
 404 #define ACC_SCALAR_3V( DST, S )     \
 405 do {                                \
 406       (DST)[0] += S;                \
 407       (DST)[1] += S;                \
 408       (DST)[2] += S;                \
 409 } while (0)
 410
 411 /** Assignment */
 412 #define ASSIGN_3V( V, V0, V1, V2 )  \
 413 do {                                \
 414     V[0] = V0;                      \
 415     V[1] = V1;                      \
 416     V[2] = V2;                      \
 417 } while(0)
 418
 419 /*@}*/
 420
 421
 422 /**********************************************************************/
 423 /** \name 2-element vector operations*/
 424 /*@{*/
 425
 426 /** Zero */
 427 #define ZERO_2V( DST )  (DST)[0] = (DST)[1] = 0
 428
 429 /** Copy a 2-element vector */
 430 #define COPY_2V( DST, SRC )         \
 431 do {                        \
 432    (DST)[0] = (SRC)[0];             \
 433    (DST)[1] = (SRC)[1];             \
 434 } while (0)
 435
 436 /** Copy a 2-element vector with cast */
 437 #define COPY_2V_CAST( DST, SRC, CAST )      \
 438 do {                        \
 439    (DST)[0] = (CAST)(SRC)[0];           \
 440    (DST)[1] = (CAST)(SRC)[1];           \
 441 } while (0)
 442
 443 /** Copy a 2-element float vector */
 444 #define COPY_2FV( DST, SRC )            \
 445 do {                        \
 446    const GLfloat *_tmp = (SRC);         \
 447    (DST)[0] = _tmp[0];              \
 448    (DST)[1] = _tmp[1];              \
 449 } while (0)
 450
 451 /** Subtraction */
 452 #define SUB_2V( DST, SRCA, SRCB )       \
 453 do {                        \
 454       (DST)[0] = (SRCA)[0] - (SRCB)[0];     \
 455       (DST)[1] = (SRCA)[1] - (SRCB)[1];     \
 456 } while (0)
 457
 458 /** Addition */
 459 #define ADD_2V( DST, SRCA, SRCB )       \
 460 do {                        \
 461       (DST)[0] = (SRCA)[0] + (SRCB)[0];     \
 462       (DST)[1] = (SRCA)[1] + (SRCB)[1];     \
 463 } while (0)
 464
 465 /** In-place scalar multiplication */
 466 #define SCALE_2V( DST, SRCA, SRCB )     \
 467 do {                        \
 468       (DST)[0] = (SRCA)[0] * (SRCB)[0];     \
 469       (DST)[1] = (SRCA)[1] * (SRCB)[1];     \
 470 } while (0)
 471
 472 /** In-place addition */
 473 #define ACC_2V( DST, SRC )          \
 474 do {                        \
 475       (DST)[0] += (SRC)[0];         \
 476       (DST)[1] += (SRC)[1];         \
 477 } while (0)
 478
 479 /** Element-wise multiplication and addition */
 480 #define ACC_SCALE_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 /** Scalar multiplication */
 487 #define SCALE_SCALAR_2V( DST, S, SRCB )     \
 488 do {                        \
 489       (DST)[0] = S * (SRCB)[0];         \
 490       (DST)[1] = S * (SRCB)[1];         \
 491 } while (0)
 492
 493 /** In-place scalar multiplication and addition */
 494 #define ACC_SCALE_SCALAR_2V( DST, S, SRCB ) \
 495 do {                        \
 496       (DST)[0] += S * (SRCB)[0];        \
 497       (DST)[1] += S * (SRCB)[1];        \
 498 } while (0)
 499
 500 /** In-place scalar multiplication */
 501 #define SELF_SCALE_SCALAR_2V( DST, S )      \
 502 do {                        \
 503       (DST)[0] *= S;                \
 504       (DST)[1] *= S;                \
 505 } while (0)
 506
 507 /** In-place scalar addition */
 508 #define ACC_SCALAR_2V( DST, S )         \
 509 do {                        \
 510       (DST)[0] += S;                \
 511       (DST)[1] += S;                \
 512 } while (0)
 513
 514 /** Assign scalers to short vectors */
 515 #define ASSIGN_2V( V, V0, V1 )  \
 516 do {                            \
 517     V[0] = V0;                  \
 518     V[1] = V1;                  \
 519 } while(0)
 520
 521 /*@}*/
 522
 523
 524 /** \name Linear interpolation macros */
 525 /*@{*/
 526
 527 /**
 528  * Linear interpolation
 529  *
 530  * \note \p OUT argument is evaluated twice!
 531  * \note Be wary of using *coord++ as an argument to any of these macros!
 532  */
 533 #define LINTERP(T, OUT, IN) ((OUT) + (T) * ((IN) - (OUT)))
 534
 535 /* Can do better with integer math
 536  */
 537 #define INTERP_UB( t, dstub, outub, inub )  \
 538 do {                        \
 539    GLfloat inf = UBYTE_TO_FLOAT( inub );    \
 540    GLfloat outf = UBYTE_TO_FLOAT( outub );  \
 541    GLfloat dstf = LINTERP( t, outf, inf );  \
 542    UNCLAMPED_FLOAT_TO_UBYTE( dstub, dstf ); \
 543 } while (0)
 544
 545 #define INTERP_CHAN( t, dstc, outc, inc )   \
 546 do {                        \
 547    GLfloat inf = CHAN_TO_FLOAT( inc );      \
 548    GLfloat outf = CHAN_TO_FLOAT( outc );    \
 549    GLfloat dstf = LINTERP( t, outf, inf );  \
 550    UNCLAMPED_FLOAT_TO_CHAN( dstc, dstf );   \
 551 } while (0)
 552
 553 #define INTERP_UI( t, dstui, outui, inui )  \
 554    dstui = (GLuint) (GLint) LINTERP( (t), (GLfloat) (outui), (GLfloat) (inui) )
 555
 556 #define INTERP_F( t, dstf, outf, inf )      \
 557    dstf = LINTERP( t, outf, inf )
 558
 559 #define INTERP_4F( t, dst, out, in )        \
 560 do {                        \
 561    dst[0] = LINTERP( (t), (out)[0], (in)[0] );  \
 562    dst[1] = LINTERP( (t), (out)[1], (in)[1] );  \
 563    dst[2] = LINTERP( (t), (out)[2], (in)[2] );  \
 564    dst[3] = LINTERP( (t), (out)[3], (in)[3] );  \
 565 } while (0)
 566
 567 #define INTERP_3F( t, dst, out, in )        \
 568 do {                        \
 569    dst[0] = LINTERP( (t), (out)[0], (in)[0] );  \
 570    dst[1] = LINTERP( (t), (out)[1], (in)[1] );  \
 571    dst[2] = LINTERP( (t), (out)[2], (in)[2] );  \
 572 } while (0)
 573
 574 #define INTERP_4CHAN( t, dst, out, in )         \
 575 do {                            \
 576    INTERP_CHAN( (t), (dst)[0], (out)[0], (in)[0] ); \
 577    INTERP_CHAN( (t), (dst)[1], (out)[1], (in)[1] ); \
 578    INTERP_CHAN( (t), (dst)[2], (out)[2], (in)[2] ); \
 579    INTERP_CHAN( (t), (dst)[3], (out)[3], (in)[3] ); \
 580 } while (0)
 581
 582 #define INTERP_3CHAN( t, dst, out, in )         \
 583 do {                            \
 584    INTERP_CHAN( (t), (dst)[0], (out)[0], (in)[0] ); \
 585    INTERP_CHAN( (t), (dst)[1], (out)[1], (in)[1] ); \
 586    INTERP_CHAN( (t), (dst)[2], (out)[2], (in)[2] ); \
 587 } while (0)
 588
 589 #define INTERP_SZ( t, vec, to, out, in, sz )                \
 590 do {                                    \
 591    switch (sz) {                            \
 592    case 4: vec[to][3] = LINTERP( (t), (vec)[out][3], (vec)[in][3] );    \
 593    case 3: vec[to][2] = LINTERP( (t), (vec)[out][2], (vec)[in][2] );    \
 594    case 2: vec[to][1] = LINTERP( (t), (vec)[out][1], (vec)[in][1] );    \
 595    case 1: vec[to][0] = LINTERP( (t), (vec)[out][0], (vec)[in][0] );    \
 596    }                                    \
 597 } while(0)
 598
 599 /*@}*/
 600
 601
 602
 603 /** Clamp X to [MIN,MAX] */
 604 #define CLAMP( X, MIN, MAX )  ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
 605
 606 /** Assign X to CLAMP(X, MIN, MAX) */
 607 #define CLAMP_SELF(x, mn, mx)  \
 608    ( (x)<(mn) ? ((x) = (mn)) : ((x)>(mx) ? ((x)=(mx)) : (x)) )
 609
 610
 611
 612 /** Minimum of two values: */
 613 #define MIN2( A, B )   ( (A)<(B) ? (A) : (B) )
 614
 615 /** Maximum of two values: */
 616 #define MAX2( A, B )   ( (A)>(B) ? (A) : (B) )
 617
 618 /** Dot product of two 2-element vectors */
 619 #define DOT2( a, b )  ( (a)[0]*(b)[0] + (a)[1]*(b)[1] )
 620
 621 /** Dot product of two 3-element vectors */
 622 #define DOT3( a, b )  ( (a)[0]*(b)[0] + (a)[1]*(b)[1] + (a)[2]*(b)[2] )
 623
 624 /** Dot product of two 4-element vectors */
 625 #define DOT4( a, b )  ( (a)[0]*(b)[0] + (a)[1]*(b)[1] + \
 626             (a)[2]*(b)[2] + (a)[3]*(b)[3] )
 627
 628 /** Dot product of two 4-element vectors */
 629 #define DOT4V(v,a,b,c,d) (v[0]*(a) + v[1]*(b) + v[2]*(c) + v[3]*(d))
 630
 631
 632 /** Cross product of two 3-element vectors */
 633 #define CROSS3(n, u, v)             \
 634 do {                        \
 635    (n)[0] = (u)[1]*(v)[2] - (u)[2]*(v)[1];  \
 636    (n)[1] = (u)[2]*(v)[0] - (u)[0]*(v)[2];  \
 637    (n)[2] = (u)[0]*(v)[1] - (u)[1]*(v)[0];  \
 638 } while (0)
 639
 640
 641 /* Normalize a 3-element vector to unit length. */
 642 #define NORMALIZE_3FV( V )          \
 643 do {                        \
 644    GLfloat len = (GLfloat) LEN_SQUARED_3FV(V);  \
 645    if (len) {                   \
 646       len = INV_SQRTF(len);         \
 647       (V)[0] = (GLfloat) ((V)[0] * len);    \
 648       (V)[1] = (GLfloat) ((V)[1] * len);    \
 649       (V)[2] = (GLfloat) ((V)[2] * len);    \
 650    }                        \
 651 } while(0)
 652
 653 #define LEN_3FV( V ) (SQRTF((V)[0]*(V)[0]+(V)[1]*(V)[1]+(V)[2]*(V)[2]))
 654 #define LEN_2FV( V ) (SQRTF((V)[0]*(V)[0]+(V)[1]*(V)[1]))
 655
 656 #define LEN_SQUARED_3FV( V ) ((V)[0]*(V)[0]+(V)[1]*(V)[1]+(V)[2]*(V)[2])
 657 #define LEN_SQUARED_2FV( V ) ((V)[0]*(V)[0]+(V)[1]*(V)[1])
 658
 659
 660 /** casts to silence warnings with some compilers */
 661 #define ENUM_TO_INT(E)     ((GLint)(E))
 662 #define ENUM_TO_FLOAT(E)   ((GLfloat)(GLint)(E))
 663 #define ENUM_TO_DOUBLE(E)  ((GLdouble)(GLint)(E))
 664 #define ENUM_TO_BOOLEAN(E) ((E) ? GL_TRUE : GL_FALSE)
 665
 666
 667 #endif