macros.h revision cf41d7c63aab2289d739c0f9df116caf2cc410e3
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] */
43extern 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 to GLfloat while preserving zero */
58#define BYTE_TO_FLOATZ(B)   ((B) == 0 ? 0.0F : BYTE_TO_FLOAT(B))
59
60
61/** Convert GLbyte in [-128,127] to GLfloat in [-1.0,1.0], texture/fb data */
62#define BYTE_TO_FLOAT_TEX(B)    ((B) == -128 ? -1.0F : (B) * (1.0F/127.0F))
63
64/** Convert GLfloat in [-1.0,1.0] to GLbyte in [-128,127], texture/fb data */
65#define FLOAT_TO_BYTE_TEX(X)    CLAMP( (GLint) (127.0F * (X)), -128, 127 )
66
67/** Convert GLushort in [0,65535] to GLfloat in [0.0,1.0] */
68#define USHORT_TO_FLOAT(S)  ((GLfloat) (S) * (1.0F / 65535.0F))
69
70/** Convert GLfloat in [0.0,1.0] to GLushort in [0, 65535] */
71#define FLOAT_TO_USHORT(X)   ((GLuint) ((X) * 65535.0F))
72
73
74/** Convert GLshort in [-32768,32767] to GLfloat in [-1.0,1.0] */
75#define SHORT_TO_FLOAT(S)   ((2.0F * (S) + 1.0F) * (1.0F/65535.0F))
76
77/** Convert GLfloat in [-1.0,1.0] to GLshort in [-32768,32767] */
78#define FLOAT_TO_SHORT(X)   ( (((GLint) (65535.0F * (X))) - 1) / 2 )
79
80/** Convert GLshort to GLfloat while preserving zero */
81#define SHORT_TO_FLOATZ(S)   ((S) == 0 ? 0.0F : SHORT_TO_FLOAT(S))
82
83
84/** Convert GLshort in [-32768,32767] to GLfloat in [-1.0,1.0], texture/fb data */
85#define SHORT_TO_FLOAT_TEX(S)    ((S) == -32768 ? -1.0F : (S) * (1.0F/32767.0F))
86
87/** Convert GLfloat in [-1.0,1.0] to GLshort in [-32768,32767], texture/fb data */
88#define FLOAT_TO_SHORT_TEX(X)    ( (GLint) (32767.0F * (X)) )
89
90
91/** Convert GLuint in [0,4294967295] to GLfloat in [0.0,1.0] */
92#define UINT_TO_FLOAT(U)    ((GLfloat) ((U) * (1.0F / 4294967295.0)))
93
94/** Convert GLfloat in [0.0,1.0] to GLuint in [0,4294967295] */
95#define FLOAT_TO_UINT(X)    ((GLuint) ((X) * 4294967295.0))
96
97
98/** Convert GLint in [-2147483648,2147483647] to GLfloat in [-1.0,1.0] */
99#define INT_TO_FLOAT(I)     ((GLfloat) ((2.0F * (I) + 1.0F) * (1.0F/4294967294.0)))
100
101/** Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647] */
102/* causes overflow:
103#define FLOAT_TO_INT(X)     ( (((GLint) (4294967294.0 * (X))) - 1) / 2 )
104*/
105/* a close approximation: */
106#define FLOAT_TO_INT(X)     ( (GLint) (2147483647.0 * (X)) )
107
108/** Convert GLfloat in [-1.0,1.0] to GLint64 in [-(1<<63),(1 << 63) -1] */
109#define FLOAT_TO_INT64(X)     ( (GLint64) (9223372036854775807.0 * (double)(X)) )
110
111
112/** Convert GLint in [-2147483648,2147483647] to GLfloat in [-1.0,1.0], texture/fb data */
113#define INT_TO_FLOAT_TEX(I)    ((I) == -2147483648 ? -1.0F : (I) * (1.0F/2147483647.0))
114
115/** Convert GLfloat in [-1.0,1.0] to GLint in [-2147483648,2147483647], texture/fb data */
116#define FLOAT_TO_INT_TEX(X)    ( (GLint) (2147483647.0 * (X)) )
117
118
119#define BYTE_TO_UBYTE(b)   ((GLubyte) ((b) < 0 ? 0 : (GLubyte) (b)))
120#define SHORT_TO_UBYTE(s)  ((GLubyte) ((s) < 0 ? 0 : (GLubyte) ((s) >> 7)))
121#define USHORT_TO_UBYTE(s) ((GLubyte) ((s) >> 8))
122#define INT_TO_UBYTE(i)    ((GLubyte) ((i) < 0 ? 0 : (GLubyte) ((i) >> 23)))
123#define UINT_TO_UBYTE(i)   ((GLubyte) ((i) >> 24))
124
125
126#define BYTE_TO_USHORT(b)  ((b) < 0 ? 0 : ((GLushort) (((b) * 65535) / 255)))
127#define UBYTE_TO_USHORT(b) (((GLushort) (b) << 8) | (GLushort) (b))
128#define SHORT_TO_USHORT(s) ((s) < 0 ? 0 : ((GLushort) (((s) * 65535 / 32767))))
129#define INT_TO_USHORT(i)   ((i) < 0 ? 0 : ((GLushort) ((i) >> 15)))
130#define UINT_TO_USHORT(i)  ((i) < 0 ? 0 : ((GLushort) ((i) >> 16)))
131#define UNCLAMPED_FLOAT_TO_USHORT(us, f)  \
132        us = ( (GLushort) F_TO_I( CLAMP((f), 0.0F, 1.0F) * 65535.0F) )
133#define CLAMPED_FLOAT_TO_USHORT(us, f)  \
134        us = ( (GLushort) F_TO_I( (f) * 65535.0F) )
135
136#define UNCLAMPED_FLOAT_TO_SHORT(s, f)  \
137        s = ( (GLshort) F_TO_I( CLAMP((f), -1.0F, 1.0F) * 32767.0F) )
138
139/***
140 *** UNCLAMPED_FLOAT_TO_UBYTE: clamp float to [0,1] and map to ubyte in [0,255]
141 *** CLAMPED_FLOAT_TO_UBYTE: map float known to be in [0,1] to ubyte in [0,255]
142 ***/
143#if defined(USE_IEEE) && !defined(DEBUG)
144#define IEEE_0996 0x3f7f0000	/* 0.996 or so */
145/* This function/macro is sensitive to precision.  Test very carefully
146 * if you change it!
147 */
148#define UNCLAMPED_FLOAT_TO_UBYTE(UB, F)					\
149        do {								\
150           fi_type __tmp;						\
151           __tmp.f = (F);						\
152           if (__tmp.i < 0)						\
153              UB = (GLubyte) 0;						\
154           else if (__tmp.i >= IEEE_0996)				\
155              UB = (GLubyte) 255;					\
156           else {							\
157              __tmp.f = __tmp.f * (255.0F/256.0F) + 32768.0F;		\
158              UB = (GLubyte) __tmp.i;					\
159           }								\
160        } while (0)
161#define CLAMPED_FLOAT_TO_UBYTE(UB, F)					\
162        do {								\
163           fi_type __tmp;						\
164           __tmp.f = (F) * (255.0F/256.0F) + 32768.0F;			\
165           UB = (GLubyte) __tmp.i;					\
166        } while (0)
167#else
168#define UNCLAMPED_FLOAT_TO_UBYTE(ub, f) \
169	ub = ((GLubyte) F_TO_I(CLAMP((f), 0.0F, 1.0F) * 255.0F))
170#define CLAMPED_FLOAT_TO_UBYTE(ub, f) \
171	ub = ((GLubyte) F_TO_I((f) * 255.0F))
172#endif
173
174/*@}*/
175
176
177/** Stepping a GLfloat pointer by a byte stride */
178#define STRIDE_F(p, i)  (p = (GLfloat *)((GLubyte *)p + i))
179/** Stepping a GLuint pointer by a byte stride */
180#define STRIDE_UI(p, i)  (p = (GLuint *)((GLubyte *)p + i))
181/** Stepping a GLubyte[4] pointer by a byte stride */
182#define STRIDE_4UB(p, i)  (p = (GLubyte (*)[4])((GLubyte *)p + i))
183/** Stepping a GLfloat[4] pointer by a byte stride */
184#define STRIDE_4F(p, i)  (p = (GLfloat (*)[4])((GLubyte *)p + i))
185/** Stepping a \p t pointer by a byte stride */
186#define STRIDE_T(p, t, i)  (p = (t)((GLubyte *)p + i))
187
188
189/**********************************************************************/
190/** \name 4-element vector operations */
191/*@{*/
192
193/** Zero */
194#define ZERO_4V( DST )  (DST)[0] = (DST)[1] = (DST)[2] = (DST)[3] = 0
195
196/** Test for equality */
197#define TEST_EQ_4V(a,b)  ((a)[0] == (b)[0] &&   \
198              (a)[1] == (b)[1] &&   \
199              (a)[2] == (b)[2] &&   \
200              (a)[3] == (b)[3])
201
202/** Test for equality (unsigned bytes) */
203#if defined(__i386__)
204#define TEST_EQ_4UBV(DST, SRC) *((GLuint*)(DST)) == *((GLuint*)(SRC))
205#else
206#define TEST_EQ_4UBV(DST, SRC) TEST_EQ_4V(DST, SRC)
207#endif
208
209/** Copy a 4-element vector */
210#define COPY_4V( DST, SRC )         \
211do {                                \
212   (DST)[0] = (SRC)[0];             \
213   (DST)[1] = (SRC)[1];             \
214   (DST)[2] = (SRC)[2];             \
215   (DST)[3] = (SRC)[3];             \
216} while (0)
217
218/** Copy a 4-element unsigned byte vector */
219#if defined(__i386__)
220#define COPY_4UBV(DST, SRC)                 \
221do {                                        \
222   *((GLuint*)(DST)) = *((GLuint*)(SRC));   \
223} while (0)
224#else
225/* The GLuint cast might fail if DST or SRC are not dword-aligned (RISC) */
226#define COPY_4UBV(DST, SRC)         \
227do {                                \
228   (DST)[0] = (SRC)[0];             \
229   (DST)[1] = (SRC)[1];             \
230   (DST)[2] = (SRC)[2];             \
231   (DST)[3] = (SRC)[3];             \
232} while (0)
233#endif
234
235/**
236 * Copy a 4-element float vector
237 * memcpy seems to be most efficient
238 */
239#define COPY_4FV( DST, SRC )                  \
240do {                                          \
241   memcpy(DST, SRC, sizeof(GLfloat) * 4);     \
242} while (0)
243
244/** Copy \p SZ elements into a 4-element vector */
245#define COPY_SZ_4V(DST, SZ, SRC)  \
246do {                              \
247   switch (SZ) {                  \
248   case 4: (DST)[3] = (SRC)[3];   \
249   case 3: (DST)[2] = (SRC)[2];   \
250   case 2: (DST)[1] = (SRC)[1];   \
251   case 1: (DST)[0] = (SRC)[0];   \
252   }                              \
253} while(0)
254
255/** Copy \p SZ elements into a homegeneous (4-element) vector, giving
256 * default values to the remaining */
257#define COPY_CLEAN_4V(DST, SZ, SRC)  \
258do {                                 \
259      ASSIGN_4V( DST, 0, 0, 0, 1 );  \
260      COPY_SZ_4V( DST, SZ, SRC );    \
261} while (0)
262
263/** Subtraction */
264#define SUB_4V( DST, SRCA, SRCB )           \
265do {                                        \
266      (DST)[0] = (SRCA)[0] - (SRCB)[0];     \
267      (DST)[1] = (SRCA)[1] - (SRCB)[1];     \
268      (DST)[2] = (SRCA)[2] - (SRCB)[2];     \
269      (DST)[3] = (SRCA)[3] - (SRCB)[3];     \
270} while (0)
271
272/** Addition */
273#define ADD_4V( DST, SRCA, SRCB )           \
274do {                                        \
275      (DST)[0] = (SRCA)[0] + (SRCB)[0];     \
276      (DST)[1] = (SRCA)[1] + (SRCB)[1];     \
277      (DST)[2] = (SRCA)[2] + (SRCB)[2];     \
278      (DST)[3] = (SRCA)[3] + (SRCB)[3];     \
279} while (0)
280
281/** Element-wise multiplication */
282#define SCALE_4V( DST, SRCA, SRCB )         \
283do {                                        \
284      (DST)[0] = (SRCA)[0] * (SRCB)[0];     \
285      (DST)[1] = (SRCA)[1] * (SRCB)[1];     \
286      (DST)[2] = (SRCA)[2] * (SRCB)[2];     \
287      (DST)[3] = (SRCA)[3] * (SRCB)[3];     \
288} while (0)
289
290/** In-place addition */
291#define ACC_4V( DST, SRC )          \
292do {                                \
293      (DST)[0] += (SRC)[0];         \
294      (DST)[1] += (SRC)[1];         \
295      (DST)[2] += (SRC)[2];         \
296      (DST)[3] += (SRC)[3];         \
297} while (0)
298
299/** Element-wise multiplication and addition */
300#define ACC_SCALE_4V( DST, SRCA, SRCB )     \
301do {                                        \
302      (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
303      (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
304      (DST)[2] += (SRCA)[2] * (SRCB)[2];    \
305      (DST)[3] += (SRCA)[3] * (SRCB)[3];    \
306} while (0)
307
308/** In-place scalar multiplication and addition */
309#define ACC_SCALE_SCALAR_4V( DST, S, SRCB ) \
310do {                                        \
311      (DST)[0] += S * (SRCB)[0];            \
312      (DST)[1] += S * (SRCB)[1];            \
313      (DST)[2] += S * (SRCB)[2];            \
314      (DST)[3] += S * (SRCB)[3];            \
315} while (0)
316
317/** Scalar multiplication */
318#define SCALE_SCALAR_4V( DST, S, SRCB ) \
319do {                                    \
320      (DST)[0] = S * (SRCB)[0];         \
321      (DST)[1] = S * (SRCB)[1];         \
322      (DST)[2] = S * (SRCB)[2];         \
323      (DST)[3] = S * (SRCB)[3];         \
324} while (0)
325
326/** In-place scalar multiplication */
327#define SELF_SCALE_SCALAR_4V( DST, S ) \
328do {                                   \
329      (DST)[0] *= S;                   \
330      (DST)[1] *= S;                   \
331      (DST)[2] *= S;                   \
332      (DST)[3] *= S;                   \
333} while (0)
334
335/** Assignment */
336#define ASSIGN_4V( V, V0, V1, V2, V3 )  \
337do {                                    \
338    V[0] = V0;                          \
339    V[1] = V1;                          \
340    V[2] = V2;                          \
341    V[3] = V3;                          \
342} while(0)
343
344/*@}*/
345
346
347/**********************************************************************/
348/** \name 3-element vector operations*/
349/*@{*/
350
351/** Zero */
352#define ZERO_3V( DST )  (DST)[0] = (DST)[1] = (DST)[2] = 0
353
354/** Test for equality */
355#define TEST_EQ_3V(a,b)  \
356   ((a)[0] == (b)[0] &&  \
357    (a)[1] == (b)[1] &&  \
358    (a)[2] == (b)[2])
359
360/** Copy a 3-element vector */
361#define COPY_3V( DST, SRC )         \
362do {                                \
363   (DST)[0] = (SRC)[0];             \
364   (DST)[1] = (SRC)[1];             \
365   (DST)[2] = (SRC)[2];             \
366} while (0)
367
368/** Copy a 3-element vector with cast */
369#define COPY_3V_CAST( DST, SRC, CAST )  \
370do {                                    \
371   (DST)[0] = (CAST)(SRC)[0];           \
372   (DST)[1] = (CAST)(SRC)[1];           \
373   (DST)[2] = (CAST)(SRC)[2];           \
374} while (0)
375
376/** Copy a 3-element float vector */
377#define COPY_3FV( DST, SRC )        \
378do {                                \
379   const GLfloat *_tmp = (SRC);     \
380   (DST)[0] = _tmp[0];              \
381   (DST)[1] = _tmp[1];              \
382   (DST)[2] = _tmp[2];              \
383} while (0)
384
385/** Subtraction */
386#define SUB_3V( DST, SRCA, SRCB )        \
387do {                                     \
388      (DST)[0] = (SRCA)[0] - (SRCB)[0];  \
389      (DST)[1] = (SRCA)[1] - (SRCB)[1];  \
390      (DST)[2] = (SRCA)[2] - (SRCB)[2];  \
391} while (0)
392
393/** Addition */
394#define ADD_3V( DST, SRCA, SRCB )       \
395do {                                    \
396      (DST)[0] = (SRCA)[0] + (SRCB)[0]; \
397      (DST)[1] = (SRCA)[1] + (SRCB)[1]; \
398      (DST)[2] = (SRCA)[2] + (SRCB)[2]; \
399} while (0)
400
401/** In-place scalar multiplication */
402#define SCALE_3V( DST, SRCA, SRCB )     \
403do {                                    \
404      (DST)[0] = (SRCA)[0] * (SRCB)[0]; \
405      (DST)[1] = (SRCA)[1] * (SRCB)[1]; \
406      (DST)[2] = (SRCA)[2] * (SRCB)[2]; \
407} while (0)
408
409/** In-place element-wise multiplication */
410#define SELF_SCALE_3V( DST, SRC )   \
411do {                                \
412      (DST)[0] *= (SRC)[0];         \
413      (DST)[1] *= (SRC)[1];         \
414      (DST)[2] *= (SRC)[2];         \
415} while (0)
416
417/** In-place addition */
418#define ACC_3V( DST, SRC )          \
419do {                                \
420      (DST)[0] += (SRC)[0];         \
421      (DST)[1] += (SRC)[1];         \
422      (DST)[2] += (SRC)[2];         \
423} while (0)
424
425/** Element-wise multiplication and addition */
426#define ACC_SCALE_3V( DST, SRCA, SRCB )     \
427do {                                        \
428      (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
429      (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
430      (DST)[2] += (SRCA)[2] * (SRCB)[2];    \
431} while (0)
432
433/** Scalar multiplication */
434#define SCALE_SCALAR_3V( DST, S, SRCB ) \
435do {                                    \
436      (DST)[0] = S * (SRCB)[0];         \
437      (DST)[1] = S * (SRCB)[1];         \
438      (DST)[2] = S * (SRCB)[2];         \
439} while (0)
440
441/** In-place scalar multiplication and addition */
442#define ACC_SCALE_SCALAR_3V( DST, S, SRCB ) \
443do {                                        \
444      (DST)[0] += S * (SRCB)[0];            \
445      (DST)[1] += S * (SRCB)[1];            \
446      (DST)[2] += S * (SRCB)[2];            \
447} while (0)
448
449/** In-place scalar multiplication */
450#define SELF_SCALE_SCALAR_3V( DST, S ) \
451do {                                   \
452      (DST)[0] *= S;                   \
453      (DST)[1] *= S;                   \
454      (DST)[2] *= S;                   \
455} while (0)
456
457/** In-place scalar addition */
458#define ACC_SCALAR_3V( DST, S )     \
459do {                                \
460      (DST)[0] += S;                \
461      (DST)[1] += S;                \
462      (DST)[2] += S;                \
463} while (0)
464
465/** Assignment */
466#define ASSIGN_3V( V, V0, V1, V2 )  \
467do {                                \
468    V[0] = V0;                      \
469    V[1] = V1;                      \
470    V[2] = V2;                      \
471} while(0)
472
473/*@}*/
474
475
476/**********************************************************************/
477/** \name 2-element vector operations*/
478/*@{*/
479
480/** Zero */
481#define ZERO_2V( DST )  (DST)[0] = (DST)[1] = 0
482
483/** Copy a 2-element vector */
484#define COPY_2V( DST, SRC )         \
485do {                        \
486   (DST)[0] = (SRC)[0];             \
487   (DST)[1] = (SRC)[1];             \
488} while (0)
489
490/** Copy a 2-element vector with cast */
491#define COPY_2V_CAST( DST, SRC, CAST )      \
492do {                        \
493   (DST)[0] = (CAST)(SRC)[0];           \
494   (DST)[1] = (CAST)(SRC)[1];           \
495} while (0)
496
497/** Copy a 2-element float vector */
498#define COPY_2FV( DST, SRC )            \
499do {                        \
500   const GLfloat *_tmp = (SRC);         \
501   (DST)[0] = _tmp[0];              \
502   (DST)[1] = _tmp[1];              \
503} while (0)
504
505/** Subtraction */
506#define SUB_2V( DST, SRCA, SRCB )       \
507do {                        \
508      (DST)[0] = (SRCA)[0] - (SRCB)[0];     \
509      (DST)[1] = (SRCA)[1] - (SRCB)[1];     \
510} while (0)
511
512/** Addition */
513#define ADD_2V( DST, SRCA, SRCB )       \
514do {                        \
515      (DST)[0] = (SRCA)[0] + (SRCB)[0];     \
516      (DST)[1] = (SRCA)[1] + (SRCB)[1];     \
517} while (0)
518
519/** In-place scalar multiplication */
520#define SCALE_2V( DST, SRCA, SRCB )     \
521do {                        \
522      (DST)[0] = (SRCA)[0] * (SRCB)[0];     \
523      (DST)[1] = (SRCA)[1] * (SRCB)[1];     \
524} while (0)
525
526/** In-place addition */
527#define ACC_2V( DST, SRC )          \
528do {                        \
529      (DST)[0] += (SRC)[0];         \
530      (DST)[1] += (SRC)[1];         \
531} while (0)
532
533/** Element-wise multiplication and addition */
534#define ACC_SCALE_2V( DST, SRCA, SRCB )     \
535do {                        \
536      (DST)[0] += (SRCA)[0] * (SRCB)[0];    \
537      (DST)[1] += (SRCA)[1] * (SRCB)[1];    \
538} while (0)
539
540/** Scalar multiplication */
541#define SCALE_SCALAR_2V( DST, S, SRCB )     \
542do {                        \
543      (DST)[0] = S * (SRCB)[0];         \
544      (DST)[1] = S * (SRCB)[1];         \
545} while (0)
546
547/** In-place scalar multiplication and addition */
548#define ACC_SCALE_SCALAR_2V( DST, S, SRCB ) \
549do {                        \
550      (DST)[0] += S * (SRCB)[0];        \
551      (DST)[1] += S * (SRCB)[1];        \
552} while (0)
553
554/** In-place scalar multiplication */
555#define SELF_SCALE_SCALAR_2V( DST, S )      \
556do {                        \
557      (DST)[0] *= S;                \
558      (DST)[1] *= S;                \
559} while (0)
560
561/** In-place scalar addition */
562#define ACC_SCALAR_2V( DST, S )         \
563do {                        \
564      (DST)[0] += S;                \
565      (DST)[1] += S;                \
566} while (0)
567
568/** Assign scalers to short vectors */
569#define ASSIGN_2V( V, V0, V1 )	\
570do {				\
571    V[0] = V0;			\
572    V[1] = V1;			\
573} while(0)
574
575/*@}*/
576
577
578/** \name Linear interpolation functions */
579/*@{*/
580
581static inline GLfloat
582LINTERP(GLfloat t, GLfloat out, GLfloat in)
583{
584   return out + t * (in - out);
585}
586
587static inline void
588INTERP_3F(GLfloat t, GLfloat dst[3], const GLfloat out[3], const GLfloat in[3])
589{
590   dst[0] = LINTERP( t, out[0], in[0] );
591   dst[1] = LINTERP( t, out[1], in[1] );
592   dst[2] = LINTERP( t, out[2], in[2] );
593}
594
595static inline void
596INTERP_4F(GLfloat t, GLfloat dst[4], const GLfloat out[4], const GLfloat in[4])
597{
598   dst[0] = LINTERP( t, out[0], in[0] );
599   dst[1] = LINTERP( t, out[1], in[1] );
600   dst[2] = LINTERP( t, out[2], in[2] );
601   dst[3] = LINTERP( t, out[3], in[3] );
602}
603
604/*@}*/
605
606
607
608/** Clamp X to [MIN,MAX] */
609#define CLAMP( X, MIN, MAX )  ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
610
611/** Minimum of two values: */
612#define MIN2( A, B )   ( (A)<(B) ? (A) : (B) )
613
614/** Maximum of two values: */
615#define MAX2( A, B )   ( (A)>(B) ? (A) : (B) )
616
617/** Minimum and maximum of three values: */
618#define MIN3( A, B, C ) ((A) < (B) ? MIN2(A, C) : MIN2(B, C))
619#define MAX3( A, B, C ) ((A) > (B) ? MAX2(A, C) : MAX2(B, C))
620
621
622
623/** Cross product of two 3-element vectors */
624static inline void
625CROSS3(GLfloat n[3], const GLfloat u[3], const GLfloat v[3])
626{
627   n[0] = u[1] * v[2] - u[2] * v[1];
628   n[1] = u[2] * v[0] - u[0] * v[2];
629   n[2] = u[0] * v[1] - u[1] * v[0];
630}
631
632
633/** Dot product of two 2-element vectors */
634static inline GLfloat
635DOT2(const GLfloat a[2], const GLfloat b[2])
636{
637   return a[0] * b[0] + a[1] * b[1];
638}
639
640static inline GLfloat
641DOT3(const GLfloat a[3], const GLfloat b[3])
642{
643   return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
644}
645
646static inline GLfloat
647DOT4(const GLfloat a[4], const GLfloat b[4])
648{
649   return a[0] * b[0] + a[1] * b[1] + a[2] * b[2] + a[3] * b[3];
650}
651
652
653static inline GLfloat
654LEN_SQUARED_3FV(const GLfloat v[3])
655{
656   return DOT3(v, v);
657}
658
659static inline GLfloat
660LEN_SQUARED_2FV(const GLfloat v[2])
661{
662   return DOT2(v, v);
663}
664
665
666static inline GLfloat
667LEN_3FV(const GLfloat v[3])
668{
669   return SQRTF(LEN_SQUARED_3FV(v));
670}
671
672static inline GLfloat
673LEN_2FV(const GLfloat v[2])
674{
675   return SQRTF(LEN_SQUARED_2FV(v));
676}
677
678
679/* Normalize a 3-element vector to unit length. */
680static inline void
681NORMALIZE_3FV(GLfloat v[3])
682{
683   GLfloat len = (GLfloat) LEN_SQUARED_3FV(v);
684   if (len) {
685      len = INV_SQRTF(len);
686      v[0] *= len;
687      v[1] *= len;
688      v[2] *= len;
689   }
690}
691
692
693/** Compute ceiling of integer quotient of A divided by B. */
694#define CEILING( A, B )  ( (A) % (B) == 0 ? (A)/(B) : (A)/(B)+1 )
695
696
697/** casts to silence warnings with some compilers */
698#define ENUM_TO_INT(E)     ((GLint)(E))
699#define ENUM_TO_FLOAT(E)   ((GLfloat)(GLint)(E))
700#define ENUM_TO_DOUBLE(E)  ((GLdouble)(GLint)(E))
701#define ENUM_TO_BOOLEAN(E) ((E) ? GL_TRUE : GL_FALSE)
702
703
704#endif
705