3 * A collection of useful macros.
7 * Mesa 3-D graphics library
10 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
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:
19 * The above copyright notice and this permission notice shall be included
20 * in all copies or substantial portions of the Software.
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.
38 * \name Integer / float conversion for colors, normals, etc.
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)]
46 /** Convert GLfloat in [0.0,1.0] to GLubyte in [0,255] */
47 #define FLOAT_TO_UBYTE(X) ((GLubyte) (GLint) ((X) * 255.0F))
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))
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 )
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))
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)) )
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))
67 /** Convert GLfloat in [0.0,1.0] to GLushort in [0, 65535] */
68 #define FLOAT_TO_USHORT(X) ((GLuint) ((X) * 65535.0F))
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))
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 )
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))
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)) )
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))
88 /** Convert GLfloat in [0.0,1.0] to GLuint in [0,4294967295] */
89 #define FLOAT_TO_UINT(X) ((GLuint) ((X) * 4294967295.0))
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))
95 /** Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647] */
97 #define FLOAT_TO_INT(X) ( (((GLint) (4294967294.0 * (X))) - 1) / 2 )
99 /* a close approximation: */
100 #define FLOAT_TO_INT(X) ( (GLint) (2147483647.0 * (X)) )
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)) )
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))
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)) )
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))
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) )
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))
149 /**********************************************************************/
150 /** \name 4-element vector operations */
154 #define ZERO_4V( DST ) (DST)[0] = (DST)[1] = (DST)[2] = (DST)[3] = 0
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] && \
162 /** Test for equality (unsigned bytes) */
163 #if defined(__i386__)
164 #define TEST_EQ_4UBV(DST, SRC) *((GLuint*)(DST)) == *((GLuint*)(SRC))
166 #define TEST_EQ_4UBV(DST, SRC) TEST_EQ_4V(DST, SRC)
169 /** Copy a 4-element vector */
170 #define COPY_4V( DST, SRC ) \
172 (DST)[0] = (SRC)[0]; \
173 (DST)[1] = (SRC)[1]; \
174 (DST)[2] = (SRC)[2]; \
175 (DST)[3] = (SRC)[3]; \
178 /** Copy a 4-element vector with cast */
179 #define COPY_4V_CAST( DST, SRC, CAST ) \
181 (DST)[0] = (CAST)(SRC)[0]; \
182 (DST)[1] = (CAST)(SRC)[1]; \
183 (DST)[2] = (CAST)(SRC)[2]; \
184 (DST)[3] = (CAST)(SRC)[3]; \
187 /** Copy a 4-element unsigned byte vector */
188 #if defined(__i386__)
189 #define COPY_4UBV(DST, SRC) \
191 *((GLuint*)(DST)) = *((GLuint*)(SRC)); \
194 /* The GLuint cast might fail if DST or SRC are not dword-aligned (RISC) */
195 #define COPY_4UBV(DST, SRC) \
197 (DST)[0] = (SRC)[0]; \
198 (DST)[1] = (SRC)[1]; \
199 (DST)[2] = (SRC)[2]; \
200 (DST)[3] = (SRC)[3]; \
205 * Copy a 4-element float vector (avoid using FPU registers)
206 * XXX Could use two 64-bit moves on 64-bit systems
208 #define COPY_4FV( DST, SRC ) \
210 const GLuint *_s = (const GLuint *) (SRC); \
211 GLuint *_d = (GLuint *) (DST); \
218 /** Copy \p SZ elements into a 4-element vector */
219 #define COPY_SZ_4V(DST, SZ, SRC) \
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]; \
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) \
233 ASSIGN_4V( DST, 0, 0, 0, 1 ); \
234 COPY_SZ_4V( DST, SZ, SRC ); \
238 #define SUB_4V( DST, SRCA, SRCB ) \
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]; \
247 #define ADD_4V( DST, SRCA, SRCB ) \
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]; \
255 /** Element-wise multiplication */
256 #define SCALE_4V( DST, SRCA, SRCB ) \
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]; \
264 /** In-place addition */
265 #define ACC_4V( DST, SRC ) \
267 (DST)[0] += (SRC)[0]; \
268 (DST)[1] += (SRC)[1]; \
269 (DST)[2] += (SRC)[2]; \
270 (DST)[3] += (SRC)[3]; \
273 /** Element-wise multiplication and addition */
274 #define ACC_SCALE_4V( DST, SRCA, SRCB ) \
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]; \
282 /** In-place scalar multiplication and addition */
283 #define ACC_SCALE_SCALAR_4V( DST, S, SRCB ) \
285 (DST)[0] += S * (SRCB)[0]; \
286 (DST)[1] += S * (SRCB)[1]; \
287 (DST)[2] += S * (SRCB)[2]; \
288 (DST)[3] += S * (SRCB)[3]; \
291 /** Scalar multiplication */
292 #define SCALE_SCALAR_4V( DST, S, SRCB ) \
294 (DST)[0] = S * (SRCB)[0]; \
295 (DST)[1] = S * (SRCB)[1]; \
296 (DST)[2] = S * (SRCB)[2]; \
297 (DST)[3] = S * (SRCB)[3]; \
300 /** In-place scalar multiplication */
301 #define SELF_SCALE_SCALAR_4V( DST, S ) \
310 #define ASSIGN_4V( V, V0, V1, V2, V3 ) \
321 /**********************************************************************/
322 /** \name 3-element vector operations*/
326 #define ZERO_3V( DST ) (DST)[0] = (DST)[1] = (DST)[2] = 0
328 /** Test for equality */
329 #define TEST_EQ_3V(a,b) \
330 ((a)[0] == (b)[0] && \
331 (a)[1] == (b)[1] && \
334 /** Copy a 3-element vector */
335 #define COPY_3V( DST, SRC ) \
337 (DST)[0] = (SRC)[0]; \
338 (DST)[1] = (SRC)[1]; \
339 (DST)[2] = (SRC)[2]; \
342 /** Copy a 3-element vector with cast */
343 #define COPY_3V_CAST( DST, SRC, CAST ) \
345 (DST)[0] = (CAST)(SRC)[0]; \
346 (DST)[1] = (CAST)(SRC)[1]; \
347 (DST)[2] = (CAST)(SRC)[2]; \
350 /** Copy a 3-element float vector */
351 #define COPY_3FV( DST, SRC ) \
353 const GLfloat *_tmp = (SRC); \
354 (DST)[0] = _tmp[0]; \
355 (DST)[1] = _tmp[1]; \
356 (DST)[2] = _tmp[2]; \
360 #define SUB_3V( DST, SRCA, SRCB ) \
362 (DST)[0] = (SRCA)[0] - (SRCB)[0]; \
363 (DST)[1] = (SRCA)[1] - (SRCB)[1]; \
364 (DST)[2] = (SRCA)[2] - (SRCB)[2]; \
368 #define ADD_3V( DST, SRCA, SRCB ) \
370 (DST)[0] = (SRCA)[0] + (SRCB)[0]; \
371 (DST)[1] = (SRCA)[1] + (SRCB)[1]; \
372 (DST)[2] = (SRCA)[2] + (SRCB)[2]; \
375 /** In-place scalar multiplication */
376 #define SCALE_3V( DST, SRCA, SRCB ) \
378 (DST)[0] = (SRCA)[0] * (SRCB)[0]; \
379 (DST)[1] = (SRCA)[1] * (SRCB)[1]; \
380 (DST)[2] = (SRCA)[2] * (SRCB)[2]; \
383 /** In-place element-wise multiplication */
384 #define SELF_SCALE_3V( DST, SRC ) \
386 (DST)[0] *= (SRC)[0]; \
387 (DST)[1] *= (SRC)[1]; \
388 (DST)[2] *= (SRC)[2]; \
391 /** In-place addition */
392 #define ACC_3V( DST, SRC ) \
394 (DST)[0] += (SRC)[0]; \
395 (DST)[1] += (SRC)[1]; \
396 (DST)[2] += (SRC)[2]; \
399 /** Element-wise multiplication and addition */
400 #define ACC_SCALE_3V( DST, SRCA, SRCB ) \
402 (DST)[0] += (SRCA)[0] * (SRCB)[0]; \
403 (DST)[1] += (SRCA)[1] * (SRCB)[1]; \
404 (DST)[2] += (SRCA)[2] * (SRCB)[2]; \
407 /** Scalar multiplication */
408 #define SCALE_SCALAR_3V( DST, S, SRCB ) \
410 (DST)[0] = S * (SRCB)[0]; \
411 (DST)[1] = S * (SRCB)[1]; \
412 (DST)[2] = S * (SRCB)[2]; \
415 /** In-place scalar multiplication and addition */
416 #define ACC_SCALE_SCALAR_3V( DST, S, SRCB ) \
418 (DST)[0] += S * (SRCB)[0]; \
419 (DST)[1] += S * (SRCB)[1]; \
420 (DST)[2] += S * (SRCB)[2]; \
423 /** In-place scalar multiplication */
424 #define SELF_SCALE_SCALAR_3V( DST, S ) \
431 /** In-place scalar addition */
432 #define ACC_SCALAR_3V( DST, S ) \
440 #define ASSIGN_3V( V, V0, V1, V2 ) \
450 /**********************************************************************/
451 /** \name 2-element vector operations*/
455 #define ZERO_2V( DST ) (DST)[0] = (DST)[1] = 0
457 /** Copy a 2-element vector */
458 #define COPY_2V( DST, SRC ) \
460 (DST)[0] = (SRC)[0]; \
461 (DST)[1] = (SRC)[1]; \
464 /** Copy a 2-element vector with cast */
465 #define COPY_2V_CAST( DST, SRC, CAST ) \
467 (DST)[0] = (CAST)(SRC)[0]; \
468 (DST)[1] = (CAST)(SRC)[1]; \
471 /** Copy a 2-element float vector */
472 #define COPY_2FV( DST, SRC ) \
474 const GLfloat *_tmp = (SRC); \
475 (DST)[0] = _tmp[0]; \
476 (DST)[1] = _tmp[1]; \
480 #define SUB_2V( DST, SRCA, SRCB ) \
482 (DST)[0] = (SRCA)[0] - (SRCB)[0]; \
483 (DST)[1] = (SRCA)[1] - (SRCB)[1]; \
487 #define ADD_2V( DST, SRCA, SRCB ) \
489 (DST)[0] = (SRCA)[0] + (SRCB)[0]; \
490 (DST)[1] = (SRCA)[1] + (SRCB)[1]; \
493 /** In-place scalar multiplication */
494 #define SCALE_2V( DST, SRCA, SRCB ) \
496 (DST)[0] = (SRCA)[0] * (SRCB)[0]; \
497 (DST)[1] = (SRCA)[1] * (SRCB)[1]; \
500 /** In-place addition */
501 #define ACC_2V( DST, SRC ) \
503 (DST)[0] += (SRC)[0]; \
504 (DST)[1] += (SRC)[1]; \
507 /** Element-wise multiplication and addition */
508 #define ACC_SCALE_2V( DST, SRCA, SRCB ) \
510 (DST)[0] += (SRCA)[0] * (SRCB)[0]; \
511 (DST)[1] += (SRCA)[1] * (SRCB)[1]; \
514 /** Scalar multiplication */
515 #define SCALE_SCALAR_2V( DST, S, SRCB ) \
517 (DST)[0] = S * (SRCB)[0]; \
518 (DST)[1] = S * (SRCB)[1]; \
521 /** In-place scalar multiplication and addition */
522 #define ACC_SCALE_SCALAR_2V( DST, S, SRCB ) \
524 (DST)[0] += S * (SRCB)[0]; \
525 (DST)[1] += S * (SRCB)[1]; \
528 /** In-place scalar multiplication */
529 #define SELF_SCALE_SCALAR_2V( DST, S ) \
535 /** In-place scalar addition */
536 #define ACC_SCALAR_2V( DST, S ) \
542 /** Assign scalers to short vectors */
543 #define ASSIGN_2V( V, V0, V1 ) \
552 /** \name Linear interpolation macros */
556 * Linear interpolation
558 * \note \p OUT argument is evaluated twice!
559 * \note Be wary of using *coord++ as an argument to any of these macros!
561 #define LINTERP(T, OUT, IN) ((OUT) + (T) * ((IN) - (OUT)))
563 /* Can do better with integer math
565 #define INTERP_UB( t, dstub, outub, inub ) \
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 ); \
573 #define INTERP_CHAN( t, dstc, outc, inc ) \
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 ); \
581 #define INTERP_UI( t, dstui, outui, inui ) \
582 dstui = (GLuint) (GLint) LINTERP( (t), (GLfloat) (outui), (GLfloat) (inui) )
584 #define INTERP_F( t, dstf, outf, inf ) \
585 dstf = LINTERP( t, outf, inf )
587 #define INTERP_4F( t, dst, out, in ) \
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] ); \
595 #define INTERP_3F( t, dst, out, in ) \
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] ); \
602 #define INTERP_4CHAN( t, dst, out, in ) \
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] ); \
610 #define INTERP_3CHAN( t, dst, out, in ) \
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] ); \
617 #define INTERP_SZ( t, vec, to, out, in, 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] ); \
631 /** Clamp X to [MIN,MAX] */
632 #define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
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)) )
640 /** Minimum of two values: */
641 #define MIN2( A, B ) ( (A)<(B) ? (A) : (B) )
643 /** Maximum of two values: */
644 #define MAX2( A, B ) ( (A)>(B) ? (A) : (B) )
646 /** Dot product of two 2-element vectors */
647 #define DOT2( a, b ) ( (a)[0]*(b)[0] + (a)[1]*(b)[1] )
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] )
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] )
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))
660 /** Cross product of two 3-element vectors */
661 #define CROSS3(n, u, v) \
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]; \
669 /* Normalize a 3-element vector to unit length. */
670 #define NORMALIZE_3FV( V ) \
672 GLfloat len = (GLfloat) LEN_SQUARED_3FV(V); \
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); \
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]))
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])
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)