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Merge remote branch 'origin/master' into pipe-video
[mesa.git] / src / mesa / swrast / s_texfilter.c
1 /*
2 * Mesa 3-D graphics library
3 * Version: 7.3
4 *
5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26 #include "main/glheader.h"
27 #include "main/context.h"
28 #include "main/colormac.h"
29 #include "main/imports.h"
30 #include "main/texformat.h"
31
32 #include "s_context.h"
33 #include "s_texfilter.h"
34
35
36 /*
37 * Note, the FRAC macro has to work perfectly. Otherwise you'll sometimes
38 * see 1-pixel bands of improperly weighted linear-filtered textures.
39 * The tests/texwrap.c demo is a good test.
40 * Also note, FRAC(x) doesn't truly return the fractional part of x for x < 0.
41 * Instead, if x < 0 then FRAC(x) = 1 - true_frac(x).
42 */
43 #define FRAC(f) ((f) - IFLOOR(f))
44
45
46
47 /**
48 * Linear interpolation macro
49 */
50 #define LERP(T, A, B) ( (A) + (T) * ((B) - (A)) )
51
52
53 /**
54 * Do 2D/biliner interpolation of float values.
55 * v00, v10, v01 and v11 are typically four texture samples in a square/box.
56 * a and b are the horizontal and vertical interpolants.
57 * It's important that this function is inlined when compiled with
58 * optimization! If we find that's not true on some systems, convert
59 * to a macro.
60 */
61 static INLINE GLfloat
62 lerp_2d(GLfloat a, GLfloat b,
63 GLfloat v00, GLfloat v10, GLfloat v01, GLfloat v11)
64 {
65 const GLfloat temp0 = LERP(a, v00, v10);
66 const GLfloat temp1 = LERP(a, v01, v11);
67 return LERP(b, temp0, temp1);
68 }
69
70
71 /**
72 * Do 3D/trilinear interpolation of float values.
73 * \sa lerp_2d
74 */
75 static INLINE GLfloat
76 lerp_3d(GLfloat a, GLfloat b, GLfloat c,
77 GLfloat v000, GLfloat v100, GLfloat v010, GLfloat v110,
78 GLfloat v001, GLfloat v101, GLfloat v011, GLfloat v111)
79 {
80 const GLfloat temp00 = LERP(a, v000, v100);
81 const GLfloat temp10 = LERP(a, v010, v110);
82 const GLfloat temp01 = LERP(a, v001, v101);
83 const GLfloat temp11 = LERP(a, v011, v111);
84 const GLfloat temp0 = LERP(b, temp00, temp10);
85 const GLfloat temp1 = LERP(b, temp01, temp11);
86 return LERP(c, temp0, temp1);
87 }
88
89
90 /**
91 * Do linear interpolation of colors.
92 */
93 static INLINE void
94 lerp_rgba(GLfloat result[4], GLfloat t, const GLfloat a[4], const GLfloat b[4])
95 {
96 result[0] = LERP(t, a[0], b[0]);
97 result[1] = LERP(t, a[1], b[1]);
98 result[2] = LERP(t, a[2], b[2]);
99 result[3] = LERP(t, a[3], b[3]);
100 }
101
102
103 /**
104 * Do bilinear interpolation of colors.
105 */
106 static INLINE void
107 lerp_rgba_2d(GLfloat result[4], GLfloat a, GLfloat b,
108 const GLfloat t00[4], const GLfloat t10[4],
109 const GLfloat t01[4], const GLfloat t11[4])
110 {
111 result[0] = lerp_2d(a, b, t00[0], t10[0], t01[0], t11[0]);
112 result[1] = lerp_2d(a, b, t00[1], t10[1], t01[1], t11[1]);
113 result[2] = lerp_2d(a, b, t00[2], t10[2], t01[2], t11[2]);
114 result[3] = lerp_2d(a, b, t00[3], t10[3], t01[3], t11[3]);
115 }
116
117
118 /**
119 * Do trilinear interpolation of colors.
120 */
121 static INLINE void
122 lerp_rgba_3d(GLfloat result[4], GLfloat a, GLfloat b, GLfloat c,
123 const GLfloat t000[4], const GLfloat t100[4],
124 const GLfloat t010[4], const GLfloat t110[4],
125 const GLfloat t001[4], const GLfloat t101[4],
126 const GLfloat t011[4], const GLfloat t111[4])
127 {
128 GLuint k;
129 /* compiler should unroll these short loops */
130 for (k = 0; k < 4; k++) {
131 result[k] = lerp_3d(a, b, c, t000[k], t100[k], t010[k], t110[k],
132 t001[k], t101[k], t011[k], t111[k]);
133 }
134 }
135
136
137 /**
138 * Used for GL_REPEAT wrap mode. Using A % B doesn't produce the
139 * right results for A<0. Casting to A to be unsigned only works if B
140 * is a power of two. Adding a bias to A (which is a multiple of B)
141 * avoids the problems with A < 0 (for reasonable A) without using a
142 * conditional.
143 */
144 #define REMAINDER(A, B) (((A) + (B) * 1024) % (B))
145
146
147 /**
148 * Used to compute texel locations for linear sampling.
149 * Input:
150 * wrapMode = GL_REPEAT, GL_CLAMP, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_BORDER
151 * s = texcoord in [0,1]
152 * size = width (or height or depth) of texture
153 * Output:
154 * i0, i1 = returns two nearest texel indexes
155 * weight = returns blend factor between texels
156 */
157 static INLINE void
158 linear_texel_locations(GLenum wrapMode,
159 const struct gl_texture_image *img,
160 GLint size, GLfloat s,
161 GLint *i0, GLint *i1, GLfloat *weight)
162 {
163 GLfloat u;
164 switch (wrapMode) {
165 case GL_REPEAT:
166 u = s * size - 0.5F;
167 if (img->_IsPowerOfTwo) {
168 *i0 = IFLOOR(u) & (size - 1);
169 *i1 = (*i0 + 1) & (size - 1);
170 }
171 else {
172 *i0 = REMAINDER(IFLOOR(u), size);
173 *i1 = REMAINDER(*i0 + 1, size);
174 }
175 break;
176 case GL_CLAMP_TO_EDGE:
177 if (s <= 0.0F)
178 u = 0.0F;
179 else if (s >= 1.0F)
180 u = (GLfloat) size;
181 else
182 u = s * size;
183 u -= 0.5F;
184 *i0 = IFLOOR(u);
185 *i1 = *i0 + 1;
186 if (*i0 < 0)
187 *i0 = 0;
188 if (*i1 >= (GLint) size)
189 *i1 = size - 1;
190 break;
191 case GL_CLAMP_TO_BORDER:
192 {
193 const GLfloat min = -1.0F / (2.0F * size);
194 const GLfloat max = 1.0F - min;
195 if (s <= min)
196 u = min * size;
197 else if (s >= max)
198 u = max * size;
199 else
200 u = s * size;
201 u -= 0.5F;
202 *i0 = IFLOOR(u);
203 *i1 = *i0 + 1;
204 }
205 break;
206 case GL_MIRRORED_REPEAT:
207 {
208 const GLint flr = IFLOOR(s);
209 if (flr & 1)
210 u = 1.0F - (s - (GLfloat) flr);
211 else
212 u = s - (GLfloat) flr;
213 u = (u * size) - 0.5F;
214 *i0 = IFLOOR(u);
215 *i1 = *i0 + 1;
216 if (*i0 < 0)
217 *i0 = 0;
218 if (*i1 >= (GLint) size)
219 *i1 = size - 1;
220 }
221 break;
222 case GL_MIRROR_CLAMP_EXT:
223 u = FABSF(s);
224 if (u >= 1.0F)
225 u = (GLfloat) size;
226 else
227 u *= size;
228 u -= 0.5F;
229 *i0 = IFLOOR(u);
230 *i1 = *i0 + 1;
231 break;
232 case GL_MIRROR_CLAMP_TO_EDGE_EXT:
233 u = FABSF(s);
234 if (u >= 1.0F)
235 u = (GLfloat) size;
236 else
237 u *= size;
238 u -= 0.5F;
239 *i0 = IFLOOR(u);
240 *i1 = *i0 + 1;
241 if (*i0 < 0)
242 *i0 = 0;
243 if (*i1 >= (GLint) size)
244 *i1 = size - 1;
245 break;
246 case GL_MIRROR_CLAMP_TO_BORDER_EXT:
247 {
248 const GLfloat min = -1.0F / (2.0F * size);
249 const GLfloat max = 1.0F - min;
250 u = FABSF(s);
251 if (u <= min)
252 u = min * size;
253 else if (u >= max)
254 u = max * size;
255 else
256 u *= size;
257 u -= 0.5F;
258 *i0 = IFLOOR(u);
259 *i1 = *i0 + 1;
260 }
261 break;
262 case GL_CLAMP:
263 if (s <= 0.0F)
264 u = 0.0F;
265 else if (s >= 1.0F)
266 u = (GLfloat) size;
267 else
268 u = s * size;
269 u -= 0.5F;
270 *i0 = IFLOOR(u);
271 *i1 = *i0 + 1;
272 break;
273 default:
274 _mesa_problem(NULL, "Bad wrap mode");
275 u = 0.0F;
276 }
277 *weight = FRAC(u);
278 }
279
280
281 /**
282 * Used to compute texel location for nearest sampling.
283 */
284 static INLINE GLint
285 nearest_texel_location(GLenum wrapMode,
286 const struct gl_texture_image *img,
287 GLint size, GLfloat s)
288 {
289 GLint i;
290
291 switch (wrapMode) {
292 case GL_REPEAT:
293 /* s limited to [0,1) */
294 /* i limited to [0,size-1] */
295 i = IFLOOR(s * size);
296 if (img->_IsPowerOfTwo)
297 i &= (size - 1);
298 else
299 i = REMAINDER(i, size);
300 return i;
301 case GL_CLAMP_TO_EDGE:
302 {
303 /* s limited to [min,max] */
304 /* i limited to [0, size-1] */
305 const GLfloat min = 1.0F / (2.0F * size);
306 const GLfloat max = 1.0F - min;
307 if (s < min)
308 i = 0;
309 else if (s > max)
310 i = size - 1;
311 else
312 i = IFLOOR(s * size);
313 }
314 return i;
315 case GL_CLAMP_TO_BORDER:
316 {
317 /* s limited to [min,max] */
318 /* i limited to [-1, size] */
319 const GLfloat min = -1.0F / (2.0F * size);
320 const GLfloat max = 1.0F - min;
321 if (s <= min)
322 i = -1;
323 else if (s >= max)
324 i = size;
325 else
326 i = IFLOOR(s * size);
327 }
328 return i;
329 case GL_MIRRORED_REPEAT:
330 {
331 const GLfloat min = 1.0F / (2.0F * size);
332 const GLfloat max = 1.0F - min;
333 const GLint flr = IFLOOR(s);
334 GLfloat u;
335 if (flr & 1)
336 u = 1.0F - (s - (GLfloat) flr);
337 else
338 u = s - (GLfloat) flr;
339 if (u < min)
340 i = 0;
341 else if (u > max)
342 i = size - 1;
343 else
344 i = IFLOOR(u * size);
345 }
346 return i;
347 case GL_MIRROR_CLAMP_EXT:
348 {
349 /* s limited to [0,1] */
350 /* i limited to [0,size-1] */
351 const GLfloat u = FABSF(s);
352 if (u <= 0.0F)
353 i = 0;
354 else if (u >= 1.0F)
355 i = size - 1;
356 else
357 i = IFLOOR(u * size);
358 }
359 return i;
360 case GL_MIRROR_CLAMP_TO_EDGE_EXT:
361 {
362 /* s limited to [min,max] */
363 /* i limited to [0, size-1] */
364 const GLfloat min = 1.0F / (2.0F * size);
365 const GLfloat max = 1.0F - min;
366 const GLfloat u = FABSF(s);
367 if (u < min)
368 i = 0;
369 else if (u > max)
370 i = size - 1;
371 else
372 i = IFLOOR(u * size);
373 }
374 return i;
375 case GL_MIRROR_CLAMP_TO_BORDER_EXT:
376 {
377 /* s limited to [min,max] */
378 /* i limited to [0, size-1] */
379 const GLfloat min = -1.0F / (2.0F * size);
380 const GLfloat max = 1.0F - min;
381 const GLfloat u = FABSF(s);
382 if (u < min)
383 i = -1;
384 else if (u > max)
385 i = size;
386 else
387 i = IFLOOR(u * size);
388 }
389 return i;
390 case GL_CLAMP:
391 /* s limited to [0,1] */
392 /* i limited to [0,size-1] */
393 if (s <= 0.0F)
394 i = 0;
395 else if (s >= 1.0F)
396 i = size - 1;
397 else
398 i = IFLOOR(s * size);
399 return i;
400 default:
401 _mesa_problem(NULL, "Bad wrap mode");
402 return 0;
403 }
404 }
405
406
407 /* Power of two image sizes only */
408 static INLINE void
409 linear_repeat_texel_location(GLuint size, GLfloat s,
410 GLint *i0, GLint *i1, GLfloat *weight)
411 {
412 GLfloat u = s * size - 0.5F;
413 *i0 = IFLOOR(u) & (size - 1);
414 *i1 = (*i0 + 1) & (size - 1);
415 *weight = FRAC(u);
416 }
417
418
419 /**
420 * Do clamp/wrap for a texture rectangle coord, GL_NEAREST filter mode.
421 */
422 static INLINE GLint
423 clamp_rect_coord_nearest(GLenum wrapMode, GLfloat coord, GLint max)
424 {
425 switch (wrapMode) {
426 case GL_CLAMP:
427 return IFLOOR( CLAMP(coord, 0.0F, max - 1) );
428 case GL_CLAMP_TO_EDGE:
429 return IFLOOR( CLAMP(coord, 0.5F, max - 0.5F) );
430 case GL_CLAMP_TO_BORDER:
431 return IFLOOR( CLAMP(coord, -0.5F, max + 0.5F) );
432 default:
433 _mesa_problem(NULL, "bad wrapMode in clamp_rect_coord_nearest");
434 return 0;
435 }
436 }
437
438
439 /**
440 * As above, but GL_LINEAR filtering.
441 */
442 static INLINE void
443 clamp_rect_coord_linear(GLenum wrapMode, GLfloat coord, GLint max,
444 GLint *i0out, GLint *i1out, GLfloat *weight)
445 {
446 GLfloat fcol;
447 GLint i0, i1;
448 switch (wrapMode) {
449 case GL_CLAMP:
450 /* Not exactly what the spec says, but it matches NVIDIA output */
451 fcol = CLAMP(coord - 0.5F, 0.0F, max - 1);
452 i0 = IFLOOR(fcol);
453 i1 = i0 + 1;
454 break;
455 case GL_CLAMP_TO_EDGE:
456 fcol = CLAMP(coord, 0.5F, max - 0.5F);
457 fcol -= 0.5F;
458 i0 = IFLOOR(fcol);
459 i1 = i0 + 1;
460 if (i1 > max - 1)
461 i1 = max - 1;
462 break;
463 case GL_CLAMP_TO_BORDER:
464 fcol = CLAMP(coord, -0.5F, max + 0.5F);
465 fcol -= 0.5F;
466 i0 = IFLOOR(fcol);
467 i1 = i0 + 1;
468 break;
469 default:
470 _mesa_problem(NULL, "bad wrapMode in clamp_rect_coord_linear");
471 i0 = i1 = 0;
472 fcol = 0.0F;
473 }
474 *i0out = i0;
475 *i1out = i1;
476 *weight = FRAC(fcol);
477 }
478
479
480 /**
481 * Compute slice/image to use for 1D or 2D array texture.
482 */
483 static INLINE GLint
484 tex_array_slice(GLfloat coord, GLsizei size)
485 {
486 GLint slice = IFLOOR(coord + 0.5f);
487 slice = CLAMP(slice, 0, size - 1);
488 return slice;
489 }
490
491
492 /**
493 * Compute nearest integer texcoords for given texobj and coordinate.
494 * NOTE: only used for depth texture sampling.
495 */
496 static INLINE void
497 nearest_texcoord(const struct gl_texture_object *texObj,
498 GLuint level,
499 const GLfloat texcoord[4],
500 GLint *i, GLint *j, GLint *k)
501 {
502 const struct gl_texture_image *img = texObj->Image[0][level];
503 const GLint width = img->Width;
504 const GLint height = img->Height;
505 const GLint depth = img->Depth;
506
507 switch (texObj->Target) {
508 case GL_TEXTURE_RECTANGLE_ARB:
509 *i = clamp_rect_coord_nearest(texObj->WrapS, texcoord[0], width);
510 *j = clamp_rect_coord_nearest(texObj->WrapT, texcoord[1], height);
511 *k = 0;
512 break;
513 case GL_TEXTURE_1D:
514 *i = nearest_texel_location(texObj->WrapS, img, width, texcoord[0]);
515 *j = 0;
516 *k = 0;
517 break;
518 case GL_TEXTURE_2D:
519 *i = nearest_texel_location(texObj->WrapS, img, width, texcoord[0]);
520 *j = nearest_texel_location(texObj->WrapT, img, height, texcoord[1]);
521 *k = 0;
522 break;
523 case GL_TEXTURE_1D_ARRAY_EXT:
524 *i = nearest_texel_location(texObj->WrapS, img, width, texcoord[0]);
525 *j = tex_array_slice(texcoord[1], height);
526 *k = 0;
527 break;
528 case GL_TEXTURE_2D_ARRAY_EXT:
529 *i = nearest_texel_location(texObj->WrapS, img, width, texcoord[0]);
530 *j = nearest_texel_location(texObj->WrapT, img, height, texcoord[1]);
531 *k = tex_array_slice(texcoord[2], depth);
532 break;
533 default:
534 *i = *j = *k = 0;
535 }
536 }
537
538
539 /**
540 * Compute linear integer texcoords for given texobj and coordinate.
541 * NOTE: only used for depth texture sampling.
542 */
543 static INLINE void
544 linear_texcoord(const struct gl_texture_object *texObj,
545 GLuint level,
546 const GLfloat texcoord[4],
547 GLint *i0, GLint *i1, GLint *j0, GLint *j1, GLint *slice,
548 GLfloat *wi, GLfloat *wj)
549 {
550 const struct gl_texture_image *img = texObj->Image[0][level];
551 const GLint width = img->Width;
552 const GLint height = img->Height;
553 const GLint depth = img->Depth;
554
555 switch (texObj->Target) {
556 case GL_TEXTURE_RECTANGLE_ARB:
557 clamp_rect_coord_linear(texObj->WrapS, texcoord[0],
558 width, i0, i1, wi);
559 clamp_rect_coord_linear(texObj->WrapT, texcoord[1],
560 height, j0, j1, wj);
561 *slice = 0;
562 break;
563
564 case GL_TEXTURE_1D:
565 case GL_TEXTURE_2D:
566 linear_texel_locations(texObj->WrapS, img, width,
567 texcoord[0], i0, i1, wi);
568 linear_texel_locations(texObj->WrapT, img, height,
569 texcoord[1], j0, j1, wj);
570 *slice = 0;
571 break;
572
573 case GL_TEXTURE_1D_ARRAY_EXT:
574 linear_texel_locations(texObj->WrapS, img, width,
575 texcoord[0], i0, i1, wi);
576 *j0 = tex_array_slice(texcoord[1], height);
577 *j1 = *j0;
578 *slice = 0;
579 break;
580
581 case GL_TEXTURE_2D_ARRAY_EXT:
582 linear_texel_locations(texObj->WrapS, img, width,
583 texcoord[0], i0, i1, wi);
584 linear_texel_locations(texObj->WrapT, img, height,
585 texcoord[1], j0, j1, wj);
586 *slice = tex_array_slice(texcoord[2], depth);
587 break;
588
589 default:
590 *slice = 0;
591 }
592 }
593
594
595
596 /**
597 * For linear interpolation between mipmap levels N and N+1, this function
598 * computes N.
599 */
600 static INLINE GLint
601 linear_mipmap_level(const struct gl_texture_object *tObj, GLfloat lambda)
602 {
603 if (lambda < 0.0F)
604 return tObj->BaseLevel;
605 else if (lambda > tObj->_MaxLambda)
606 return (GLint) (tObj->BaseLevel + tObj->_MaxLambda);
607 else
608 return (GLint) (tObj->BaseLevel + lambda);
609 }
610
611
612 /**
613 * Compute the nearest mipmap level to take texels from.
614 */
615 static INLINE GLint
616 nearest_mipmap_level(const struct gl_texture_object *tObj, GLfloat lambda)
617 {
618 GLfloat l;
619 GLint level;
620 if (lambda <= 0.5F)
621 l = 0.0F;
622 else if (lambda > tObj->_MaxLambda + 0.4999F)
623 l = tObj->_MaxLambda + 0.4999F;
624 else
625 l = lambda;
626 level = (GLint) (tObj->BaseLevel + l + 0.5F);
627 if (level > tObj->_MaxLevel)
628 level = tObj->_MaxLevel;
629 return level;
630 }
631
632
633
634 /*
635 * Bitflags for texture border color sampling.
636 */
637 #define I0BIT 1
638 #define I1BIT 2
639 #define J0BIT 4
640 #define J1BIT 8
641 #define K0BIT 16
642 #define K1BIT 32
643
644
645
646 /**
647 * The lambda[] array values are always monotonic. Either the whole span
648 * will be minified, magnified, or split between the two. This function
649 * determines the subranges in [0, n-1] that are to be minified or magnified.
650 */
651 static INLINE void
652 compute_min_mag_ranges(const struct gl_texture_object *tObj,
653 GLuint n, const GLfloat lambda[],
654 GLuint *minStart, GLuint *minEnd,
655 GLuint *magStart, GLuint *magEnd)
656 {
657 GLfloat minMagThresh;
658
659 /* we shouldn't be here if minfilter == magfilter */
660 ASSERT(tObj->MinFilter != tObj->MagFilter);
661
662 /* This bit comes from the OpenGL spec: */
663 if (tObj->MagFilter == GL_LINEAR
664 && (tObj->MinFilter == GL_NEAREST_MIPMAP_NEAREST ||
665 tObj->MinFilter == GL_NEAREST_MIPMAP_LINEAR)) {
666 minMagThresh = 0.5F;
667 }
668 else {
669 minMagThresh = 0.0F;
670 }
671
672 #if 0
673 /* DEBUG CODE: Verify that lambda[] is monotonic.
674 * We can't really use this because the inaccuracy in the LOG2 function
675 * causes this test to fail, yet the resulting texturing is correct.
676 */
677 if (n > 1) {
678 GLuint i;
679 printf("lambda delta = %g\n", lambda[0] - lambda[n-1]);
680 if (lambda[0] >= lambda[n-1]) { /* decreasing */
681 for (i = 0; i < n - 1; i++) {
682 ASSERT((GLint) (lambda[i] * 10) >= (GLint) (lambda[i+1] * 10));
683 }
684 }
685 else { /* increasing */
686 for (i = 0; i < n - 1; i++) {
687 ASSERT((GLint) (lambda[i] * 10) <= (GLint) (lambda[i+1] * 10));
688 }
689 }
690 }
691 #endif /* DEBUG */
692
693 if (lambda[0] <= minMagThresh && (n <= 1 || lambda[n-1] <= minMagThresh)) {
694 /* magnification for whole span */
695 *magStart = 0;
696 *magEnd = n;
697 *minStart = *minEnd = 0;
698 }
699 else if (lambda[0] > minMagThresh && (n <=1 || lambda[n-1] > minMagThresh)) {
700 /* minification for whole span */
701 *minStart = 0;
702 *minEnd = n;
703 *magStart = *magEnd = 0;
704 }
705 else {
706 /* a mix of minification and magnification */
707 GLuint i;
708 if (lambda[0] > minMagThresh) {
709 /* start with minification */
710 for (i = 1; i < n; i++) {
711 if (lambda[i] <= minMagThresh)
712 break;
713 }
714 *minStart = 0;
715 *minEnd = i;
716 *magStart = i;
717 *magEnd = n;
718 }
719 else {
720 /* start with magnification */
721 for (i = 1; i < n; i++) {
722 if (lambda[i] > minMagThresh)
723 break;
724 }
725 *magStart = 0;
726 *magEnd = i;
727 *minStart = i;
728 *minEnd = n;
729 }
730 }
731
732 #if 0
733 /* Verify the min/mag Start/End values
734 * We don't use this either (see above)
735 */
736 {
737 GLint i;
738 for (i = 0; i < n; i++) {
739 if (lambda[i] > minMagThresh) {
740 /* minification */
741 ASSERT(i >= *minStart);
742 ASSERT(i < *minEnd);
743 }
744 else {
745 /* magnification */
746 ASSERT(i >= *magStart);
747 ASSERT(i < *magEnd);
748 }
749 }
750 }
751 #endif
752 }
753
754
755 /**
756 * When we sample the border color, it must be interpreted according to
757 * the base texture format. Ex: if the texture base format it GL_ALPHA,
758 * we return (0,0,0,BorderAlpha).
759 */
760 static INLINE void
761 get_border_color(const struct gl_texture_object *tObj,
762 const struct gl_texture_image *img,
763 GLfloat rgba[4])
764 {
765 switch (img->_BaseFormat) {
766 case GL_RGB:
767 rgba[0] = tObj->BorderColor.f[0];
768 rgba[1] = tObj->BorderColor.f[1];
769 rgba[2] = tObj->BorderColor.f[2];
770 rgba[3] = 1.0F;
771 break;
772 case GL_ALPHA:
773 rgba[0] = rgba[1] = rgba[2] = 0.0;
774 rgba[3] = tObj->BorderColor.f[3];
775 break;
776 case GL_LUMINANCE:
777 rgba[0] = rgba[1] = rgba[2] = tObj->BorderColor.f[0];
778 rgba[3] = 1.0;
779 break;
780 case GL_LUMINANCE_ALPHA:
781 rgba[0] = rgba[1] = rgba[2] = tObj->BorderColor.f[0];
782 rgba[3] = tObj->BorderColor.f[3];
783 break;
784 case GL_INTENSITY:
785 rgba[0] = rgba[1] = rgba[2] = rgba[3] = tObj->BorderColor.f[0];
786 break;
787 default:
788 COPY_4V(rgba, tObj->BorderColor.f);
789 }
790 }
791
792
793 /**********************************************************************/
794 /* 1-D Texture Sampling Functions */
795 /**********************************************************************/
796
797 /**
798 * Return the texture sample for coordinate (s) using GL_NEAREST filter.
799 */
800 static INLINE void
801 sample_1d_nearest(struct gl_context *ctx,
802 const struct gl_texture_object *tObj,
803 const struct gl_texture_image *img,
804 const GLfloat texcoord[4], GLfloat rgba[4])
805 {
806 const GLint width = img->Width2; /* without border, power of two */
807 GLint i;
808 i = nearest_texel_location(tObj->WrapS, img, width, texcoord[0]);
809 /* skip over the border, if any */
810 i += img->Border;
811 if (i < 0 || i >= (GLint) img->Width) {
812 /* Need this test for GL_CLAMP_TO_BORDER mode */
813 get_border_color(tObj, img, rgba);
814 }
815 else {
816 img->FetchTexelf(img, i, 0, 0, rgba);
817 }
818 }
819
820
821 /**
822 * Return the texture sample for coordinate (s) using GL_LINEAR filter.
823 */
824 static INLINE void
825 sample_1d_linear(struct gl_context *ctx,
826 const struct gl_texture_object *tObj,
827 const struct gl_texture_image *img,
828 const GLfloat texcoord[4], GLfloat rgba[4])
829 {
830 const GLint width = img->Width2;
831 GLint i0, i1;
832 GLbitfield useBorderColor = 0x0;
833 GLfloat a;
834 GLfloat t0[4], t1[4]; /* texels */
835
836 linear_texel_locations(tObj->WrapS, img, width, texcoord[0], &i0, &i1, &a);
837
838 if (img->Border) {
839 i0 += img->Border;
840 i1 += img->Border;
841 }
842 else {
843 if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT;
844 if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT;
845 }
846
847 /* fetch texel colors */
848 if (useBorderColor & I0BIT) {
849 get_border_color(tObj, img, t0);
850 }
851 else {
852 img->FetchTexelf(img, i0, 0, 0, t0);
853 }
854 if (useBorderColor & I1BIT) {
855 get_border_color(tObj, img, t1);
856 }
857 else {
858 img->FetchTexelf(img, i1, 0, 0, t1);
859 }
860
861 lerp_rgba(rgba, a, t0, t1);
862 }
863
864
865 static void
866 sample_1d_nearest_mipmap_nearest(struct gl_context *ctx,
867 const struct gl_texture_object *tObj,
868 GLuint n, const GLfloat texcoord[][4],
869 const GLfloat lambda[], GLfloat rgba[][4])
870 {
871 GLuint i;
872 ASSERT(lambda != NULL);
873 for (i = 0; i < n; i++) {
874 GLint level = nearest_mipmap_level(tObj, lambda[i]);
875 sample_1d_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]);
876 }
877 }
878
879
880 static void
881 sample_1d_linear_mipmap_nearest(struct gl_context *ctx,
882 const struct gl_texture_object *tObj,
883 GLuint n, const GLfloat texcoord[][4],
884 const GLfloat lambda[], GLfloat rgba[][4])
885 {
886 GLuint i;
887 ASSERT(lambda != NULL);
888 for (i = 0; i < n; i++) {
889 GLint level = nearest_mipmap_level(tObj, lambda[i]);
890 sample_1d_linear(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]);
891 }
892 }
893
894
895 static void
896 sample_1d_nearest_mipmap_linear(struct gl_context *ctx,
897 const struct gl_texture_object *tObj,
898 GLuint n, const GLfloat texcoord[][4],
899 const GLfloat lambda[], GLfloat rgba[][4])
900 {
901 GLuint i;
902 ASSERT(lambda != NULL);
903 for (i = 0; i < n; i++) {
904 GLint level = linear_mipmap_level(tObj, lambda[i]);
905 if (level >= tObj->_MaxLevel) {
906 sample_1d_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
907 texcoord[i], rgba[i]);
908 }
909 else {
910 GLfloat t0[4], t1[4];
911 const GLfloat f = FRAC(lambda[i]);
912 sample_1d_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
913 sample_1d_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
914 lerp_rgba(rgba[i], f, t0, t1);
915 }
916 }
917 }
918
919
920 static void
921 sample_1d_linear_mipmap_linear(struct gl_context *ctx,
922 const struct gl_texture_object *tObj,
923 GLuint n, const GLfloat texcoord[][4],
924 const GLfloat lambda[], GLfloat rgba[][4])
925 {
926 GLuint i;
927 ASSERT(lambda != NULL);
928 for (i = 0; i < n; i++) {
929 GLint level = linear_mipmap_level(tObj, lambda[i]);
930 if (level >= tObj->_MaxLevel) {
931 sample_1d_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
932 texcoord[i], rgba[i]);
933 }
934 else {
935 GLfloat t0[4], t1[4];
936 const GLfloat f = FRAC(lambda[i]);
937 sample_1d_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
938 sample_1d_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
939 lerp_rgba(rgba[i], f, t0, t1);
940 }
941 }
942 }
943
944
945 /** Sample 1D texture, nearest filtering for both min/magnification */
946 static void
947 sample_nearest_1d( struct gl_context *ctx,
948 const struct gl_texture_object *tObj, GLuint n,
949 const GLfloat texcoords[][4], const GLfloat lambda[],
950 GLfloat rgba[][4] )
951 {
952 GLuint i;
953 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
954 (void) lambda;
955 for (i = 0; i < n; i++) {
956 sample_1d_nearest(ctx, tObj, image, texcoords[i], rgba[i]);
957 }
958 }
959
960
961 /** Sample 1D texture, linear filtering for both min/magnification */
962 static void
963 sample_linear_1d( struct gl_context *ctx,
964 const struct gl_texture_object *tObj, GLuint n,
965 const GLfloat texcoords[][4], const GLfloat lambda[],
966 GLfloat rgba[][4] )
967 {
968 GLuint i;
969 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
970 (void) lambda;
971 for (i = 0; i < n; i++) {
972 sample_1d_linear(ctx, tObj, image, texcoords[i], rgba[i]);
973 }
974 }
975
976
977 /** Sample 1D texture, using lambda to choose between min/magnification */
978 static void
979 sample_lambda_1d( struct gl_context *ctx,
980 const struct gl_texture_object *tObj, GLuint n,
981 const GLfloat texcoords[][4],
982 const GLfloat lambda[], GLfloat rgba[][4] )
983 {
984 GLuint minStart, minEnd; /* texels with minification */
985 GLuint magStart, magEnd; /* texels with magnification */
986 GLuint i;
987
988 ASSERT(lambda != NULL);
989 compute_min_mag_ranges(tObj, n, lambda,
990 &minStart, &minEnd, &magStart, &magEnd);
991
992 if (minStart < minEnd) {
993 /* do the minified texels */
994 const GLuint m = minEnd - minStart;
995 switch (tObj->MinFilter) {
996 case GL_NEAREST:
997 for (i = minStart; i < minEnd; i++)
998 sample_1d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
999 texcoords[i], rgba[i]);
1000 break;
1001 case GL_LINEAR:
1002 for (i = minStart; i < minEnd; i++)
1003 sample_1d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1004 texcoords[i], rgba[i]);
1005 break;
1006 case GL_NEAREST_MIPMAP_NEAREST:
1007 sample_1d_nearest_mipmap_nearest(ctx, tObj, m, texcoords + minStart,
1008 lambda + minStart, rgba + minStart);
1009 break;
1010 case GL_LINEAR_MIPMAP_NEAREST:
1011 sample_1d_linear_mipmap_nearest(ctx, tObj, m, texcoords + minStart,
1012 lambda + minStart, rgba + minStart);
1013 break;
1014 case GL_NEAREST_MIPMAP_LINEAR:
1015 sample_1d_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart,
1016 lambda + minStart, rgba + minStart);
1017 break;
1018 case GL_LINEAR_MIPMAP_LINEAR:
1019 sample_1d_linear_mipmap_linear(ctx, tObj, m, texcoords + minStart,
1020 lambda + minStart, rgba + minStart);
1021 break;
1022 default:
1023 _mesa_problem(ctx, "Bad min filter in sample_1d_texture");
1024 return;
1025 }
1026 }
1027
1028 if (magStart < magEnd) {
1029 /* do the magnified texels */
1030 switch (tObj->MagFilter) {
1031 case GL_NEAREST:
1032 for (i = magStart; i < magEnd; i++)
1033 sample_1d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1034 texcoords[i], rgba[i]);
1035 break;
1036 case GL_LINEAR:
1037 for (i = magStart; i < magEnd; i++)
1038 sample_1d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1039 texcoords[i], rgba[i]);
1040 break;
1041 default:
1042 _mesa_problem(ctx, "Bad mag filter in sample_1d_texture");
1043 return;
1044 }
1045 }
1046 }
1047
1048
1049 /**********************************************************************/
1050 /* 2-D Texture Sampling Functions */
1051 /**********************************************************************/
1052
1053
1054 /**
1055 * Return the texture sample for coordinate (s,t) using GL_NEAREST filter.
1056 */
1057 static INLINE void
1058 sample_2d_nearest(struct gl_context *ctx,
1059 const struct gl_texture_object *tObj,
1060 const struct gl_texture_image *img,
1061 const GLfloat texcoord[4],
1062 GLfloat rgba[])
1063 {
1064 const GLint width = img->Width2; /* without border, power of two */
1065 const GLint height = img->Height2; /* without border, power of two */
1066 GLint i, j;
1067 (void) ctx;
1068
1069 i = nearest_texel_location(tObj->WrapS, img, width, texcoord[0]);
1070 j = nearest_texel_location(tObj->WrapT, img, height, texcoord[1]);
1071
1072 /* skip over the border, if any */
1073 i += img->Border;
1074 j += img->Border;
1075
1076 if (i < 0 || i >= (GLint) img->Width || j < 0 || j >= (GLint) img->Height) {
1077 /* Need this test for GL_CLAMP_TO_BORDER mode */
1078 get_border_color(tObj, img, rgba);
1079 }
1080 else {
1081 img->FetchTexelf(img, i, j, 0, rgba);
1082 }
1083 }
1084
1085
1086 /**
1087 * Return the texture sample for coordinate (s,t) using GL_LINEAR filter.
1088 * New sampling code contributed by Lynn Quam <quam@ai.sri.com>.
1089 */
1090 static INLINE void
1091 sample_2d_linear(struct gl_context *ctx,
1092 const struct gl_texture_object *tObj,
1093 const struct gl_texture_image *img,
1094 const GLfloat texcoord[4],
1095 GLfloat rgba[])
1096 {
1097 const GLint width = img->Width2;
1098 const GLint height = img->Height2;
1099 GLint i0, j0, i1, j1;
1100 GLbitfield useBorderColor = 0x0;
1101 GLfloat a, b;
1102 GLfloat t00[4], t10[4], t01[4], t11[4]; /* sampled texel colors */
1103
1104 linear_texel_locations(tObj->WrapS, img, width, texcoord[0], &i0, &i1, &a);
1105 linear_texel_locations(tObj->WrapT, img, height, texcoord[1], &j0, &j1, &b);
1106
1107 if (img->Border) {
1108 i0 += img->Border;
1109 i1 += img->Border;
1110 j0 += img->Border;
1111 j1 += img->Border;
1112 }
1113 else {
1114 if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT;
1115 if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT;
1116 if (j0 < 0 || j0 >= height) useBorderColor |= J0BIT;
1117 if (j1 < 0 || j1 >= height) useBorderColor |= J1BIT;
1118 }
1119
1120 /* fetch four texel colors */
1121 if (useBorderColor & (I0BIT | J0BIT)) {
1122 get_border_color(tObj, img, t00);
1123 }
1124 else {
1125 img->FetchTexelf(img, i0, j0, 0, t00);
1126 }
1127 if (useBorderColor & (I1BIT | J0BIT)) {
1128 get_border_color(tObj, img, t10);
1129 }
1130 else {
1131 img->FetchTexelf(img, i1, j0, 0, t10);
1132 }
1133 if (useBorderColor & (I0BIT | J1BIT)) {
1134 get_border_color(tObj, img, t01);
1135 }
1136 else {
1137 img->FetchTexelf(img, i0, j1, 0, t01);
1138 }
1139 if (useBorderColor & (I1BIT | J1BIT)) {
1140 get_border_color(tObj, img, t11);
1141 }
1142 else {
1143 img->FetchTexelf(img, i1, j1, 0, t11);
1144 }
1145
1146 lerp_rgba_2d(rgba, a, b, t00, t10, t01, t11);
1147 }
1148
1149
1150 /**
1151 * As above, but we know WRAP_S == REPEAT and WRAP_T == REPEAT.
1152 * We don't have to worry about the texture border.
1153 */
1154 static INLINE void
1155 sample_2d_linear_repeat(struct gl_context *ctx,
1156 const struct gl_texture_object *tObj,
1157 const struct gl_texture_image *img,
1158 const GLfloat texcoord[4],
1159 GLfloat rgba[])
1160 {
1161 const GLint width = img->Width2;
1162 const GLint height = img->Height2;
1163 GLint i0, j0, i1, j1;
1164 GLfloat wi, wj;
1165 GLfloat t00[4], t10[4], t01[4], t11[4]; /* sampled texel colors */
1166
1167 (void) ctx;
1168
1169 ASSERT(tObj->WrapS == GL_REPEAT);
1170 ASSERT(tObj->WrapT == GL_REPEAT);
1171 ASSERT(img->Border == 0);
1172 ASSERT(img->_BaseFormat != GL_COLOR_INDEX);
1173 ASSERT(img->_IsPowerOfTwo);
1174
1175 linear_repeat_texel_location(width, texcoord[0], &i0, &i1, &wi);
1176 linear_repeat_texel_location(height, texcoord[1], &j0, &j1, &wj);
1177
1178 img->FetchTexelf(img, i0, j0, 0, t00);
1179 img->FetchTexelf(img, i1, j0, 0, t10);
1180 img->FetchTexelf(img, i0, j1, 0, t01);
1181 img->FetchTexelf(img, i1, j1, 0, t11);
1182
1183 lerp_rgba_2d(rgba, wi, wj, t00, t10, t01, t11);
1184 }
1185
1186
1187 static void
1188 sample_2d_nearest_mipmap_nearest(struct gl_context *ctx,
1189 const struct gl_texture_object *tObj,
1190 GLuint n, const GLfloat texcoord[][4],
1191 const GLfloat lambda[], GLfloat rgba[][4])
1192 {
1193 GLuint i;
1194 for (i = 0; i < n; i++) {
1195 GLint level = nearest_mipmap_level(tObj, lambda[i]);
1196 sample_2d_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]);
1197 }
1198 }
1199
1200
1201 static void
1202 sample_2d_linear_mipmap_nearest(struct gl_context *ctx,
1203 const struct gl_texture_object *tObj,
1204 GLuint n, const GLfloat texcoord[][4],
1205 const GLfloat lambda[], GLfloat rgba[][4])
1206 {
1207 GLuint i;
1208 ASSERT(lambda != NULL);
1209 for (i = 0; i < n; i++) {
1210 GLint level = nearest_mipmap_level(tObj, lambda[i]);
1211 sample_2d_linear(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]);
1212 }
1213 }
1214
1215
1216 static void
1217 sample_2d_nearest_mipmap_linear(struct gl_context *ctx,
1218 const struct gl_texture_object *tObj,
1219 GLuint n, const GLfloat texcoord[][4],
1220 const GLfloat lambda[], GLfloat rgba[][4])
1221 {
1222 GLuint i;
1223 ASSERT(lambda != NULL);
1224 for (i = 0; i < n; i++) {
1225 GLint level = linear_mipmap_level(tObj, lambda[i]);
1226 if (level >= tObj->_MaxLevel) {
1227 sample_2d_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
1228 texcoord[i], rgba[i]);
1229 }
1230 else {
1231 GLfloat t0[4], t1[4]; /* texels */
1232 const GLfloat f = FRAC(lambda[i]);
1233 sample_2d_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
1234 sample_2d_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
1235 lerp_rgba(rgba[i], f, t0, t1);
1236 }
1237 }
1238 }
1239
1240
1241 static void
1242 sample_2d_linear_mipmap_linear( struct gl_context *ctx,
1243 const struct gl_texture_object *tObj,
1244 GLuint n, const GLfloat texcoord[][4],
1245 const GLfloat lambda[], GLfloat rgba[][4] )
1246 {
1247 GLuint i;
1248 ASSERT(lambda != NULL);
1249 for (i = 0; i < n; i++) {
1250 GLint level = linear_mipmap_level(tObj, lambda[i]);
1251 if (level >= tObj->_MaxLevel) {
1252 sample_2d_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
1253 texcoord[i], rgba[i]);
1254 }
1255 else {
1256 GLfloat t0[4], t1[4]; /* texels */
1257 const GLfloat f = FRAC(lambda[i]);
1258 sample_2d_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
1259 sample_2d_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
1260 lerp_rgba(rgba[i], f, t0, t1);
1261 }
1262 }
1263 }
1264
1265
1266 static void
1267 sample_2d_linear_mipmap_linear_repeat(struct gl_context *ctx,
1268 const struct gl_texture_object *tObj,
1269 GLuint n, const GLfloat texcoord[][4],
1270 const GLfloat lambda[], GLfloat rgba[][4])
1271 {
1272 GLuint i;
1273 ASSERT(lambda != NULL);
1274 ASSERT(tObj->WrapS == GL_REPEAT);
1275 ASSERT(tObj->WrapT == GL_REPEAT);
1276 for (i = 0; i < n; i++) {
1277 GLint level = linear_mipmap_level(tObj, lambda[i]);
1278 if (level >= tObj->_MaxLevel) {
1279 sample_2d_linear_repeat(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
1280 texcoord[i], rgba[i]);
1281 }
1282 else {
1283 GLfloat t0[4], t1[4]; /* texels */
1284 const GLfloat f = FRAC(lambda[i]);
1285 sample_2d_linear_repeat(ctx, tObj, tObj->Image[0][level ],
1286 texcoord[i], t0);
1287 sample_2d_linear_repeat(ctx, tObj, tObj->Image[0][level+1],
1288 texcoord[i], t1);
1289 lerp_rgba(rgba[i], f, t0, t1);
1290 }
1291 }
1292 }
1293
1294
1295 /** Sample 2D texture, nearest filtering for both min/magnification */
1296 static void
1297 sample_nearest_2d(struct gl_context *ctx,
1298 const struct gl_texture_object *tObj, GLuint n,
1299 const GLfloat texcoords[][4],
1300 const GLfloat lambda[], GLfloat rgba[][4])
1301 {
1302 GLuint i;
1303 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
1304 (void) lambda;
1305 for (i = 0; i < n; i++) {
1306 sample_2d_nearest(ctx, tObj, image, texcoords[i], rgba[i]);
1307 }
1308 }
1309
1310
1311 /** Sample 2D texture, linear filtering for both min/magnification */
1312 static void
1313 sample_linear_2d(struct gl_context *ctx,
1314 const struct gl_texture_object *tObj, GLuint n,
1315 const GLfloat texcoords[][4],
1316 const GLfloat lambda[], GLfloat rgba[][4])
1317 {
1318 GLuint i;
1319 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
1320 (void) lambda;
1321 if (tObj->WrapS == GL_REPEAT &&
1322 tObj->WrapT == GL_REPEAT &&
1323 image->_IsPowerOfTwo &&
1324 image->Border == 0) {
1325 for (i = 0; i < n; i++) {
1326 sample_2d_linear_repeat(ctx, tObj, image, texcoords[i], rgba[i]);
1327 }
1328 }
1329 else {
1330 for (i = 0; i < n; i++) {
1331 sample_2d_linear(ctx, tObj, image, texcoords[i], rgba[i]);
1332 }
1333 }
1334 }
1335
1336
1337 /**
1338 * Optimized 2-D texture sampling:
1339 * S and T wrap mode == GL_REPEAT
1340 * GL_NEAREST min/mag filter
1341 * No border,
1342 * RowStride == Width,
1343 * Format = GL_RGB
1344 */
1345 static void
1346 opt_sample_rgb_2d(struct gl_context *ctx,
1347 const struct gl_texture_object *tObj,
1348 GLuint n, const GLfloat texcoords[][4],
1349 const GLfloat lambda[], GLfloat rgba[][4])
1350 {
1351 const struct gl_texture_image *img = tObj->Image[0][tObj->BaseLevel];
1352 const GLfloat width = (GLfloat) img->Width;
1353 const GLfloat height = (GLfloat) img->Height;
1354 const GLint colMask = img->Width - 1;
1355 const GLint rowMask = img->Height - 1;
1356 const GLint shift = img->WidthLog2;
1357 GLuint k;
1358 (void) ctx;
1359 (void) lambda;
1360 ASSERT(tObj->WrapS==GL_REPEAT);
1361 ASSERT(tObj->WrapT==GL_REPEAT);
1362 ASSERT(img->Border==0);
1363 ASSERT(img->TexFormat == MESA_FORMAT_RGB888);
1364 ASSERT(img->_IsPowerOfTwo);
1365
1366 for (k=0; k<n; k++) {
1367 GLint i = IFLOOR(texcoords[k][0] * width) & colMask;
1368 GLint j = IFLOOR(texcoords[k][1] * height) & rowMask;
1369 GLint pos = (j << shift) | i;
1370 GLubyte *texel = ((GLubyte *) img->Data) + 3*pos;
1371 rgba[k][RCOMP] = UBYTE_TO_FLOAT(texel[2]);
1372 rgba[k][GCOMP] = UBYTE_TO_FLOAT(texel[1]);
1373 rgba[k][BCOMP] = UBYTE_TO_FLOAT(texel[0]);
1374 rgba[k][ACOMP] = 1.0F;
1375 }
1376 }
1377
1378
1379 /**
1380 * Optimized 2-D texture sampling:
1381 * S and T wrap mode == GL_REPEAT
1382 * GL_NEAREST min/mag filter
1383 * No border
1384 * RowStride == Width,
1385 * Format = GL_RGBA
1386 */
1387 static void
1388 opt_sample_rgba_2d(struct gl_context *ctx,
1389 const struct gl_texture_object *tObj,
1390 GLuint n, const GLfloat texcoords[][4],
1391 const GLfloat lambda[], GLfloat rgba[][4])
1392 {
1393 const struct gl_texture_image *img = tObj->Image[0][tObj->BaseLevel];
1394 const GLfloat width = (GLfloat) img->Width;
1395 const GLfloat height = (GLfloat) img->Height;
1396 const GLint colMask = img->Width - 1;
1397 const GLint rowMask = img->Height - 1;
1398 const GLint shift = img->WidthLog2;
1399 GLuint i;
1400 (void) ctx;
1401 (void) lambda;
1402 ASSERT(tObj->WrapS==GL_REPEAT);
1403 ASSERT(tObj->WrapT==GL_REPEAT);
1404 ASSERT(img->Border==0);
1405 ASSERT(img->TexFormat == MESA_FORMAT_RGBA8888);
1406 ASSERT(img->_IsPowerOfTwo);
1407
1408 for (i = 0; i < n; i++) {
1409 const GLint col = IFLOOR(texcoords[i][0] * width) & colMask;
1410 const GLint row = IFLOOR(texcoords[i][1] * height) & rowMask;
1411 const GLint pos = (row << shift) | col;
1412 const GLuint texel = *((GLuint *) img->Data + pos);
1413 rgba[i][RCOMP] = UBYTE_TO_FLOAT( (texel >> 24) );
1414 rgba[i][GCOMP] = UBYTE_TO_FLOAT( (texel >> 16) & 0xff );
1415 rgba[i][BCOMP] = UBYTE_TO_FLOAT( (texel >> 8) & 0xff );
1416 rgba[i][ACOMP] = UBYTE_TO_FLOAT( (texel ) & 0xff );
1417 }
1418 }
1419
1420
1421 /** Sample 2D texture, using lambda to choose between min/magnification */
1422 static void
1423 sample_lambda_2d(struct gl_context *ctx,
1424 const struct gl_texture_object *tObj,
1425 GLuint n, const GLfloat texcoords[][4],
1426 const GLfloat lambda[], GLfloat rgba[][4])
1427 {
1428 const struct gl_texture_image *tImg = tObj->Image[0][tObj->BaseLevel];
1429 GLuint minStart, minEnd; /* texels with minification */
1430 GLuint magStart, magEnd; /* texels with magnification */
1431
1432 const GLboolean repeatNoBorderPOT = (tObj->WrapS == GL_REPEAT)
1433 && (tObj->WrapT == GL_REPEAT)
1434 && (tImg->Border == 0 && (tImg->Width == tImg->RowStride))
1435 && (tImg->_BaseFormat != GL_COLOR_INDEX)
1436 && tImg->_IsPowerOfTwo;
1437
1438 ASSERT(lambda != NULL);
1439 compute_min_mag_ranges(tObj, n, lambda,
1440 &minStart, &minEnd, &magStart, &magEnd);
1441
1442 if (minStart < minEnd) {
1443 /* do the minified texels */
1444 const GLuint m = minEnd - minStart;
1445 switch (tObj->MinFilter) {
1446 case GL_NEAREST:
1447 if (repeatNoBorderPOT) {
1448 switch (tImg->TexFormat) {
1449 case MESA_FORMAT_RGB888:
1450 opt_sample_rgb_2d(ctx, tObj, m, texcoords + minStart,
1451 NULL, rgba + minStart);
1452 break;
1453 case MESA_FORMAT_RGBA8888:
1454 opt_sample_rgba_2d(ctx, tObj, m, texcoords + minStart,
1455 NULL, rgba + minStart);
1456 break;
1457 default:
1458 sample_nearest_2d(ctx, tObj, m, texcoords + minStart,
1459 NULL, rgba + minStart );
1460 }
1461 }
1462 else {
1463 sample_nearest_2d(ctx, tObj, m, texcoords + minStart,
1464 NULL, rgba + minStart);
1465 }
1466 break;
1467 case GL_LINEAR:
1468 sample_linear_2d(ctx, tObj, m, texcoords + minStart,
1469 NULL, rgba + minStart);
1470 break;
1471 case GL_NEAREST_MIPMAP_NEAREST:
1472 sample_2d_nearest_mipmap_nearest(ctx, tObj, m,
1473 texcoords + minStart,
1474 lambda + minStart, rgba + minStart);
1475 break;
1476 case GL_LINEAR_MIPMAP_NEAREST:
1477 sample_2d_linear_mipmap_nearest(ctx, tObj, m, texcoords + minStart,
1478 lambda + minStart, rgba + minStart);
1479 break;
1480 case GL_NEAREST_MIPMAP_LINEAR:
1481 sample_2d_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart,
1482 lambda + minStart, rgba + minStart);
1483 break;
1484 case GL_LINEAR_MIPMAP_LINEAR:
1485 if (repeatNoBorderPOT)
1486 sample_2d_linear_mipmap_linear_repeat(ctx, tObj, m,
1487 texcoords + minStart, lambda + minStart, rgba + minStart);
1488 else
1489 sample_2d_linear_mipmap_linear(ctx, tObj, m, texcoords + minStart,
1490 lambda + minStart, rgba + minStart);
1491 break;
1492 default:
1493 _mesa_problem(ctx, "Bad min filter in sample_2d_texture");
1494 return;
1495 }
1496 }
1497
1498 if (magStart < magEnd) {
1499 /* do the magnified texels */
1500 const GLuint m = magEnd - magStart;
1501
1502 switch (tObj->MagFilter) {
1503 case GL_NEAREST:
1504 if (repeatNoBorderPOT) {
1505 switch (tImg->TexFormat) {
1506 case MESA_FORMAT_RGB888:
1507 opt_sample_rgb_2d(ctx, tObj, m, texcoords + magStart,
1508 NULL, rgba + magStart);
1509 break;
1510 case MESA_FORMAT_RGBA8888:
1511 opt_sample_rgba_2d(ctx, tObj, m, texcoords + magStart,
1512 NULL, rgba + magStart);
1513 break;
1514 default:
1515 sample_nearest_2d(ctx, tObj, m, texcoords + magStart,
1516 NULL, rgba + magStart );
1517 }
1518 }
1519 else {
1520 sample_nearest_2d(ctx, tObj, m, texcoords + magStart,
1521 NULL, rgba + magStart);
1522 }
1523 break;
1524 case GL_LINEAR:
1525 sample_linear_2d(ctx, tObj, m, texcoords + magStart,
1526 NULL, rgba + magStart);
1527 break;
1528 default:
1529 _mesa_problem(ctx, "Bad mag filter in sample_lambda_2d");
1530 }
1531 }
1532 }
1533
1534
1535
1536 /**********************************************************************/
1537 /* 3-D Texture Sampling Functions */
1538 /**********************************************************************/
1539
1540 /**
1541 * Return the texture sample for coordinate (s,t,r) using GL_NEAREST filter.
1542 */
1543 static INLINE void
1544 sample_3d_nearest(struct gl_context *ctx,
1545 const struct gl_texture_object *tObj,
1546 const struct gl_texture_image *img,
1547 const GLfloat texcoord[4],
1548 GLfloat rgba[4])
1549 {
1550 const GLint width = img->Width2; /* without border, power of two */
1551 const GLint height = img->Height2; /* without border, power of two */
1552 const GLint depth = img->Depth2; /* without border, power of two */
1553 GLint i, j, k;
1554 (void) ctx;
1555
1556 i = nearest_texel_location(tObj->WrapS, img, width, texcoord[0]);
1557 j = nearest_texel_location(tObj->WrapT, img, height, texcoord[1]);
1558 k = nearest_texel_location(tObj->WrapR, img, depth, texcoord[2]);
1559
1560 if (i < 0 || i >= (GLint) img->Width ||
1561 j < 0 || j >= (GLint) img->Height ||
1562 k < 0 || k >= (GLint) img->Depth) {
1563 /* Need this test for GL_CLAMP_TO_BORDER mode */
1564 get_border_color(tObj, img, rgba);
1565 }
1566 else {
1567 img->FetchTexelf(img, i, j, k, rgba);
1568 }
1569 }
1570
1571
1572 /**
1573 * Return the texture sample for coordinate (s,t,r) using GL_LINEAR filter.
1574 */
1575 static void
1576 sample_3d_linear(struct gl_context *ctx,
1577 const struct gl_texture_object *tObj,
1578 const struct gl_texture_image *img,
1579 const GLfloat texcoord[4],
1580 GLfloat rgba[4])
1581 {
1582 const GLint width = img->Width2;
1583 const GLint height = img->Height2;
1584 const GLint depth = img->Depth2;
1585 GLint i0, j0, k0, i1, j1, k1;
1586 GLbitfield useBorderColor = 0x0;
1587 GLfloat a, b, c;
1588 GLfloat t000[4], t010[4], t001[4], t011[4];
1589 GLfloat t100[4], t110[4], t101[4], t111[4];
1590
1591 linear_texel_locations(tObj->WrapS, img, width, texcoord[0], &i0, &i1, &a);
1592 linear_texel_locations(tObj->WrapT, img, height, texcoord[1], &j0, &j1, &b);
1593 linear_texel_locations(tObj->WrapR, img, depth, texcoord[2], &k0, &k1, &c);
1594
1595 if (img->Border) {
1596 i0 += img->Border;
1597 i1 += img->Border;
1598 j0 += img->Border;
1599 j1 += img->Border;
1600 k0 += img->Border;
1601 k1 += img->Border;
1602 }
1603 else {
1604 /* check if sampling texture border color */
1605 if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT;
1606 if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT;
1607 if (j0 < 0 || j0 >= height) useBorderColor |= J0BIT;
1608 if (j1 < 0 || j1 >= height) useBorderColor |= J1BIT;
1609 if (k0 < 0 || k0 >= depth) useBorderColor |= K0BIT;
1610 if (k1 < 0 || k1 >= depth) useBorderColor |= K1BIT;
1611 }
1612
1613 /* Fetch texels */
1614 if (useBorderColor & (I0BIT | J0BIT | K0BIT)) {
1615 get_border_color(tObj, img, t000);
1616 }
1617 else {
1618 img->FetchTexelf(img, i0, j0, k0, t000);
1619 }
1620 if (useBorderColor & (I1BIT | J0BIT | K0BIT)) {
1621 get_border_color(tObj, img, t100);
1622 }
1623 else {
1624 img->FetchTexelf(img, i1, j0, k0, t100);
1625 }
1626 if (useBorderColor & (I0BIT | J1BIT | K0BIT)) {
1627 get_border_color(tObj, img, t010);
1628 }
1629 else {
1630 img->FetchTexelf(img, i0, j1, k0, t010);
1631 }
1632 if (useBorderColor & (I1BIT | J1BIT | K0BIT)) {
1633 get_border_color(tObj, img, t110);
1634 }
1635 else {
1636 img->FetchTexelf(img, i1, j1, k0, t110);
1637 }
1638
1639 if (useBorderColor & (I0BIT | J0BIT | K1BIT)) {
1640 get_border_color(tObj, img, t001);
1641 }
1642 else {
1643 img->FetchTexelf(img, i0, j0, k1, t001);
1644 }
1645 if (useBorderColor & (I1BIT | J0BIT | K1BIT)) {
1646 get_border_color(tObj, img, t101);
1647 }
1648 else {
1649 img->FetchTexelf(img, i1, j0, k1, t101);
1650 }
1651 if (useBorderColor & (I0BIT | J1BIT | K1BIT)) {
1652 get_border_color(tObj, img, t011);
1653 }
1654 else {
1655 img->FetchTexelf(img, i0, j1, k1, t011);
1656 }
1657 if (useBorderColor & (I1BIT | J1BIT | K1BIT)) {
1658 get_border_color(tObj, img, t111);
1659 }
1660 else {
1661 img->FetchTexelf(img, i1, j1, k1, t111);
1662 }
1663
1664 /* trilinear interpolation of samples */
1665 lerp_rgba_3d(rgba, a, b, c, t000, t100, t010, t110, t001, t101, t011, t111);
1666 }
1667
1668
1669 static void
1670 sample_3d_nearest_mipmap_nearest(struct gl_context *ctx,
1671 const struct gl_texture_object *tObj,
1672 GLuint n, const GLfloat texcoord[][4],
1673 const GLfloat lambda[], GLfloat rgba[][4] )
1674 {
1675 GLuint i;
1676 for (i = 0; i < n; i++) {
1677 GLint level = nearest_mipmap_level(tObj, lambda[i]);
1678 sample_3d_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]);
1679 }
1680 }
1681
1682
1683 static void
1684 sample_3d_linear_mipmap_nearest(struct gl_context *ctx,
1685 const struct gl_texture_object *tObj,
1686 GLuint n, const GLfloat texcoord[][4],
1687 const GLfloat lambda[], GLfloat rgba[][4])
1688 {
1689 GLuint i;
1690 ASSERT(lambda != NULL);
1691 for (i = 0; i < n; i++) {
1692 GLint level = nearest_mipmap_level(tObj, lambda[i]);
1693 sample_3d_linear(ctx, tObj, tObj->Image[0][level], texcoord[i], rgba[i]);
1694 }
1695 }
1696
1697
1698 static void
1699 sample_3d_nearest_mipmap_linear(struct gl_context *ctx,
1700 const struct gl_texture_object *tObj,
1701 GLuint n, const GLfloat texcoord[][4],
1702 const GLfloat lambda[], GLfloat rgba[][4])
1703 {
1704 GLuint i;
1705 ASSERT(lambda != NULL);
1706 for (i = 0; i < n; i++) {
1707 GLint level = linear_mipmap_level(tObj, lambda[i]);
1708 if (level >= tObj->_MaxLevel) {
1709 sample_3d_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
1710 texcoord[i], rgba[i]);
1711 }
1712 else {
1713 GLfloat t0[4], t1[4]; /* texels */
1714 const GLfloat f = FRAC(lambda[i]);
1715 sample_3d_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
1716 sample_3d_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
1717 lerp_rgba(rgba[i], f, t0, t1);
1718 }
1719 }
1720 }
1721
1722
1723 static void
1724 sample_3d_linear_mipmap_linear(struct gl_context *ctx,
1725 const struct gl_texture_object *tObj,
1726 GLuint n, const GLfloat texcoord[][4],
1727 const GLfloat lambda[], GLfloat rgba[][4])
1728 {
1729 GLuint i;
1730 ASSERT(lambda != NULL);
1731 for (i = 0; i < n; i++) {
1732 GLint level = linear_mipmap_level(tObj, lambda[i]);
1733 if (level >= tObj->_MaxLevel) {
1734 sample_3d_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
1735 texcoord[i], rgba[i]);
1736 }
1737 else {
1738 GLfloat t0[4], t1[4]; /* texels */
1739 const GLfloat f = FRAC(lambda[i]);
1740 sample_3d_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
1741 sample_3d_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
1742 lerp_rgba(rgba[i], f, t0, t1);
1743 }
1744 }
1745 }
1746
1747
1748 /** Sample 3D texture, nearest filtering for both min/magnification */
1749 static void
1750 sample_nearest_3d(struct gl_context *ctx,
1751 const struct gl_texture_object *tObj, GLuint n,
1752 const GLfloat texcoords[][4], const GLfloat lambda[],
1753 GLfloat rgba[][4])
1754 {
1755 GLuint i;
1756 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
1757 (void) lambda;
1758 for (i = 0; i < n; i++) {
1759 sample_3d_nearest(ctx, tObj, image, texcoords[i], rgba[i]);
1760 }
1761 }
1762
1763
1764 /** Sample 3D texture, linear filtering for both min/magnification */
1765 static void
1766 sample_linear_3d(struct gl_context *ctx,
1767 const struct gl_texture_object *tObj, GLuint n,
1768 const GLfloat texcoords[][4],
1769 const GLfloat lambda[], GLfloat rgba[][4])
1770 {
1771 GLuint i;
1772 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
1773 (void) lambda;
1774 for (i = 0; i < n; i++) {
1775 sample_3d_linear(ctx, tObj, image, texcoords[i], rgba[i]);
1776 }
1777 }
1778
1779
1780 /** Sample 3D texture, using lambda to choose between min/magnification */
1781 static void
1782 sample_lambda_3d(struct gl_context *ctx,
1783 const struct gl_texture_object *tObj, GLuint n,
1784 const GLfloat texcoords[][4], const GLfloat lambda[],
1785 GLfloat rgba[][4])
1786 {
1787 GLuint minStart, minEnd; /* texels with minification */
1788 GLuint magStart, magEnd; /* texels with magnification */
1789 GLuint i;
1790
1791 ASSERT(lambda != NULL);
1792 compute_min_mag_ranges(tObj, n, lambda,
1793 &minStart, &minEnd, &magStart, &magEnd);
1794
1795 if (minStart < minEnd) {
1796 /* do the minified texels */
1797 GLuint m = minEnd - minStart;
1798 switch (tObj->MinFilter) {
1799 case GL_NEAREST:
1800 for (i = minStart; i < minEnd; i++)
1801 sample_3d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1802 texcoords[i], rgba[i]);
1803 break;
1804 case GL_LINEAR:
1805 for (i = minStart; i < minEnd; i++)
1806 sample_3d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1807 texcoords[i], rgba[i]);
1808 break;
1809 case GL_NEAREST_MIPMAP_NEAREST:
1810 sample_3d_nearest_mipmap_nearest(ctx, tObj, m, texcoords + minStart,
1811 lambda + minStart, rgba + minStart);
1812 break;
1813 case GL_LINEAR_MIPMAP_NEAREST:
1814 sample_3d_linear_mipmap_nearest(ctx, tObj, m, texcoords + minStart,
1815 lambda + minStart, rgba + minStart);
1816 break;
1817 case GL_NEAREST_MIPMAP_LINEAR:
1818 sample_3d_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart,
1819 lambda + minStart, rgba + minStart);
1820 break;
1821 case GL_LINEAR_MIPMAP_LINEAR:
1822 sample_3d_linear_mipmap_linear(ctx, tObj, m, texcoords + minStart,
1823 lambda + minStart, rgba + minStart);
1824 break;
1825 default:
1826 _mesa_problem(ctx, "Bad min filter in sample_3d_texture");
1827 return;
1828 }
1829 }
1830
1831 if (magStart < magEnd) {
1832 /* do the magnified texels */
1833 switch (tObj->MagFilter) {
1834 case GL_NEAREST:
1835 for (i = magStart; i < magEnd; i++)
1836 sample_3d_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1837 texcoords[i], rgba[i]);
1838 break;
1839 case GL_LINEAR:
1840 for (i = magStart; i < magEnd; i++)
1841 sample_3d_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
1842 texcoords[i], rgba[i]);
1843 break;
1844 default:
1845 _mesa_problem(ctx, "Bad mag filter in sample_3d_texture");
1846 return;
1847 }
1848 }
1849 }
1850
1851
1852 /**********************************************************************/
1853 /* Texture Cube Map Sampling Functions */
1854 /**********************************************************************/
1855
1856 /**
1857 * Choose one of six sides of a texture cube map given the texture
1858 * coord (rx,ry,rz). Return pointer to corresponding array of texture
1859 * images.
1860 */
1861 static const struct gl_texture_image **
1862 choose_cube_face(const struct gl_texture_object *texObj,
1863 const GLfloat texcoord[4], GLfloat newCoord[4])
1864 {
1865 /*
1866 major axis
1867 direction target sc tc ma
1868 ---------- ------------------------------- --- --- ---
1869 +rx TEXTURE_CUBE_MAP_POSITIVE_X_EXT -rz -ry rx
1870 -rx TEXTURE_CUBE_MAP_NEGATIVE_X_EXT +rz -ry rx
1871 +ry TEXTURE_CUBE_MAP_POSITIVE_Y_EXT +rx +rz ry
1872 -ry TEXTURE_CUBE_MAP_NEGATIVE_Y_EXT +rx -rz ry
1873 +rz TEXTURE_CUBE_MAP_POSITIVE_Z_EXT +rx -ry rz
1874 -rz TEXTURE_CUBE_MAP_NEGATIVE_Z_EXT -rx -ry rz
1875 */
1876 const GLfloat rx = texcoord[0];
1877 const GLfloat ry = texcoord[1];
1878 const GLfloat rz = texcoord[2];
1879 const GLfloat arx = FABSF(rx), ary = FABSF(ry), arz = FABSF(rz);
1880 GLuint face;
1881 GLfloat sc, tc, ma;
1882
1883 if (arx >= ary && arx >= arz) {
1884 if (rx >= 0.0F) {
1885 face = FACE_POS_X;
1886 sc = -rz;
1887 tc = -ry;
1888 ma = arx;
1889 }
1890 else {
1891 face = FACE_NEG_X;
1892 sc = rz;
1893 tc = -ry;
1894 ma = arx;
1895 }
1896 }
1897 else if (ary >= arx && ary >= arz) {
1898 if (ry >= 0.0F) {
1899 face = FACE_POS_Y;
1900 sc = rx;
1901 tc = rz;
1902 ma = ary;
1903 }
1904 else {
1905 face = FACE_NEG_Y;
1906 sc = rx;
1907 tc = -rz;
1908 ma = ary;
1909 }
1910 }
1911 else {
1912 if (rz > 0.0F) {
1913 face = FACE_POS_Z;
1914 sc = rx;
1915 tc = -ry;
1916 ma = arz;
1917 }
1918 else {
1919 face = FACE_NEG_Z;
1920 sc = -rx;
1921 tc = -ry;
1922 ma = arz;
1923 }
1924 }
1925
1926 {
1927 const float ima = 1.0F / ma;
1928 newCoord[0] = ( sc * ima + 1.0F ) * 0.5F;
1929 newCoord[1] = ( tc * ima + 1.0F ) * 0.5F;
1930 }
1931
1932 return (const struct gl_texture_image **) texObj->Image[face];
1933 }
1934
1935
1936 static void
1937 sample_nearest_cube(struct gl_context *ctx,
1938 const struct gl_texture_object *tObj, GLuint n,
1939 const GLfloat texcoords[][4], const GLfloat lambda[],
1940 GLfloat rgba[][4])
1941 {
1942 GLuint i;
1943 (void) lambda;
1944 for (i = 0; i < n; i++) {
1945 const struct gl_texture_image **images;
1946 GLfloat newCoord[4];
1947 images = choose_cube_face(tObj, texcoords[i], newCoord);
1948 sample_2d_nearest(ctx, tObj, images[tObj->BaseLevel],
1949 newCoord, rgba[i]);
1950 }
1951 }
1952
1953
1954 static void
1955 sample_linear_cube(struct gl_context *ctx,
1956 const struct gl_texture_object *tObj, GLuint n,
1957 const GLfloat texcoords[][4],
1958 const GLfloat lambda[], GLfloat rgba[][4])
1959 {
1960 GLuint i;
1961 (void) lambda;
1962 for (i = 0; i < n; i++) {
1963 const struct gl_texture_image **images;
1964 GLfloat newCoord[4];
1965 images = choose_cube_face(tObj, texcoords[i], newCoord);
1966 sample_2d_linear(ctx, tObj, images[tObj->BaseLevel],
1967 newCoord, rgba[i]);
1968 }
1969 }
1970
1971
1972 static void
1973 sample_cube_nearest_mipmap_nearest(struct gl_context *ctx,
1974 const struct gl_texture_object *tObj,
1975 GLuint n, const GLfloat texcoord[][4],
1976 const GLfloat lambda[], GLfloat rgba[][4])
1977 {
1978 GLuint i;
1979 ASSERT(lambda != NULL);
1980 for (i = 0; i < n; i++) {
1981 const struct gl_texture_image **images;
1982 GLfloat newCoord[4];
1983 GLint level;
1984 images = choose_cube_face(tObj, texcoord[i], newCoord);
1985
1986 /* XXX we actually need to recompute lambda here based on the newCoords.
1987 * But we would need the texcoords of adjacent fragments to compute that
1988 * properly, and we don't have those here.
1989 * For now, do an approximation: subtracting 1 from the chosen mipmap
1990 * level seems to work in some test cases.
1991 * The same adjustment is done in the next few functions.
1992 */
1993 level = nearest_mipmap_level(tObj, lambda[i]);
1994 level = MAX2(level - 1, 0);
1995
1996 sample_2d_nearest(ctx, tObj, images[level], newCoord, rgba[i]);
1997 }
1998 }
1999
2000
2001 static void
2002 sample_cube_linear_mipmap_nearest(struct gl_context *ctx,
2003 const struct gl_texture_object *tObj,
2004 GLuint n, const GLfloat texcoord[][4],
2005 const GLfloat lambda[], GLfloat rgba[][4])
2006 {
2007 GLuint i;
2008 ASSERT(lambda != NULL);
2009 for (i = 0; i < n; i++) {
2010 const struct gl_texture_image **images;
2011 GLfloat newCoord[4];
2012 GLint level = nearest_mipmap_level(tObj, lambda[i]);
2013 level = MAX2(level - 1, 0); /* see comment above */
2014 images = choose_cube_face(tObj, texcoord[i], newCoord);
2015 sample_2d_linear(ctx, tObj, images[level], newCoord, rgba[i]);
2016 }
2017 }
2018
2019
2020 static void
2021 sample_cube_nearest_mipmap_linear(struct gl_context *ctx,
2022 const struct gl_texture_object *tObj,
2023 GLuint n, const GLfloat texcoord[][4],
2024 const GLfloat lambda[], GLfloat rgba[][4])
2025 {
2026 GLuint i;
2027 ASSERT(lambda != NULL);
2028 for (i = 0; i < n; i++) {
2029 const struct gl_texture_image **images;
2030 GLfloat newCoord[4];
2031 GLint level = linear_mipmap_level(tObj, lambda[i]);
2032 level = MAX2(level - 1, 0); /* see comment above */
2033 images = choose_cube_face(tObj, texcoord[i], newCoord);
2034 if (level >= tObj->_MaxLevel) {
2035 sample_2d_nearest(ctx, tObj, images[tObj->_MaxLevel],
2036 newCoord, rgba[i]);
2037 }
2038 else {
2039 GLfloat t0[4], t1[4]; /* texels */
2040 const GLfloat f = FRAC(lambda[i]);
2041 sample_2d_nearest(ctx, tObj, images[level ], newCoord, t0);
2042 sample_2d_nearest(ctx, tObj, images[level+1], newCoord, t1);
2043 lerp_rgba(rgba[i], f, t0, t1);
2044 }
2045 }
2046 }
2047
2048
2049 static void
2050 sample_cube_linear_mipmap_linear(struct gl_context *ctx,
2051 const struct gl_texture_object *tObj,
2052 GLuint n, const GLfloat texcoord[][4],
2053 const GLfloat lambda[], GLfloat rgba[][4])
2054 {
2055 GLuint i;
2056 ASSERT(lambda != NULL);
2057 for (i = 0; i < n; i++) {
2058 const struct gl_texture_image **images;
2059 GLfloat newCoord[4];
2060 GLint level = linear_mipmap_level(tObj, lambda[i]);
2061 level = MAX2(level - 1, 0); /* see comment above */
2062 images = choose_cube_face(tObj, texcoord[i], newCoord);
2063 if (level >= tObj->_MaxLevel) {
2064 sample_2d_linear(ctx, tObj, images[tObj->_MaxLevel],
2065 newCoord, rgba[i]);
2066 }
2067 else {
2068 GLfloat t0[4], t1[4];
2069 const GLfloat f = FRAC(lambda[i]);
2070 sample_2d_linear(ctx, tObj, images[level ], newCoord, t0);
2071 sample_2d_linear(ctx, tObj, images[level+1], newCoord, t1);
2072 lerp_rgba(rgba[i], f, t0, t1);
2073 }
2074 }
2075 }
2076
2077
2078 /** Sample cube texture, using lambda to choose between min/magnification */
2079 static void
2080 sample_lambda_cube(struct gl_context *ctx,
2081 const struct gl_texture_object *tObj, GLuint n,
2082 const GLfloat texcoords[][4], const GLfloat lambda[],
2083 GLfloat rgba[][4])
2084 {
2085 GLuint minStart, minEnd; /* texels with minification */
2086 GLuint magStart, magEnd; /* texels with magnification */
2087
2088 ASSERT(lambda != NULL);
2089 compute_min_mag_ranges(tObj, n, lambda,
2090 &minStart, &minEnd, &magStart, &magEnd);
2091
2092 if (minStart < minEnd) {
2093 /* do the minified texels */
2094 const GLuint m = minEnd - minStart;
2095 switch (tObj->MinFilter) {
2096 case GL_NEAREST:
2097 sample_nearest_cube(ctx, tObj, m, texcoords + minStart,
2098 lambda + minStart, rgba + minStart);
2099 break;
2100 case GL_LINEAR:
2101 sample_linear_cube(ctx, tObj, m, texcoords + minStart,
2102 lambda + minStart, rgba + minStart);
2103 break;
2104 case GL_NEAREST_MIPMAP_NEAREST:
2105 sample_cube_nearest_mipmap_nearest(ctx, tObj, m,
2106 texcoords + minStart,
2107 lambda + minStart, rgba + minStart);
2108 break;
2109 case GL_LINEAR_MIPMAP_NEAREST:
2110 sample_cube_linear_mipmap_nearest(ctx, tObj, m,
2111 texcoords + minStart,
2112 lambda + minStart, rgba + minStart);
2113 break;
2114 case GL_NEAREST_MIPMAP_LINEAR:
2115 sample_cube_nearest_mipmap_linear(ctx, tObj, m,
2116 texcoords + minStart,
2117 lambda + minStart, rgba + minStart);
2118 break;
2119 case GL_LINEAR_MIPMAP_LINEAR:
2120 sample_cube_linear_mipmap_linear(ctx, tObj, m,
2121 texcoords + minStart,
2122 lambda + minStart, rgba + minStart);
2123 break;
2124 default:
2125 _mesa_problem(ctx, "Bad min filter in sample_lambda_cube");
2126 }
2127 }
2128
2129 if (magStart < magEnd) {
2130 /* do the magnified texels */
2131 const GLuint m = magEnd - magStart;
2132 switch (tObj->MagFilter) {
2133 case GL_NEAREST:
2134 sample_nearest_cube(ctx, tObj, m, texcoords + magStart,
2135 lambda + magStart, rgba + magStart);
2136 break;
2137 case GL_LINEAR:
2138 sample_linear_cube(ctx, tObj, m, texcoords + magStart,
2139 lambda + magStart, rgba + magStart);
2140 break;
2141 default:
2142 _mesa_problem(ctx, "Bad mag filter in sample_lambda_cube");
2143 }
2144 }
2145 }
2146
2147
2148 /**********************************************************************/
2149 /* Texture Rectangle Sampling Functions */
2150 /**********************************************************************/
2151
2152
2153 static void
2154 sample_nearest_rect(struct gl_context *ctx,
2155 const struct gl_texture_object *tObj, GLuint n,
2156 const GLfloat texcoords[][4], const GLfloat lambda[],
2157 GLfloat rgba[][4])
2158 {
2159 const struct gl_texture_image *img = tObj->Image[0][0];
2160 const GLint width = img->Width;
2161 const GLint height = img->Height;
2162 GLuint i;
2163
2164 (void) ctx;
2165 (void) lambda;
2166
2167 ASSERT(tObj->WrapS == GL_CLAMP ||
2168 tObj->WrapS == GL_CLAMP_TO_EDGE ||
2169 tObj->WrapS == GL_CLAMP_TO_BORDER);
2170 ASSERT(tObj->WrapT == GL_CLAMP ||
2171 tObj->WrapT == GL_CLAMP_TO_EDGE ||
2172 tObj->WrapT == GL_CLAMP_TO_BORDER);
2173 ASSERT(img->_BaseFormat != GL_COLOR_INDEX);
2174
2175 for (i = 0; i < n; i++) {
2176 GLint row, col;
2177 col = clamp_rect_coord_nearest(tObj->WrapS, texcoords[i][0], width);
2178 row = clamp_rect_coord_nearest(tObj->WrapT, texcoords[i][1], height);
2179 if (col < 0 || col >= width || row < 0 || row >= height)
2180 get_border_color(tObj, img, rgba[i]);
2181 else
2182 img->FetchTexelf(img, col, row, 0, rgba[i]);
2183 }
2184 }
2185
2186
2187 static void
2188 sample_linear_rect(struct gl_context *ctx,
2189 const struct gl_texture_object *tObj, GLuint n,
2190 const GLfloat texcoords[][4],
2191 const GLfloat lambda[], GLfloat rgba[][4])
2192 {
2193 const struct gl_texture_image *img = tObj->Image[0][0];
2194 const GLint width = img->Width;
2195 const GLint height = img->Height;
2196 GLuint i;
2197
2198 (void) ctx;
2199 (void) lambda;
2200
2201 ASSERT(tObj->WrapS == GL_CLAMP ||
2202 tObj->WrapS == GL_CLAMP_TO_EDGE ||
2203 tObj->WrapS == GL_CLAMP_TO_BORDER);
2204 ASSERT(tObj->WrapT == GL_CLAMP ||
2205 tObj->WrapT == GL_CLAMP_TO_EDGE ||
2206 tObj->WrapT == GL_CLAMP_TO_BORDER);
2207 ASSERT(img->_BaseFormat != GL_COLOR_INDEX);
2208
2209 for (i = 0; i < n; i++) {
2210 GLint i0, j0, i1, j1;
2211 GLfloat t00[4], t01[4], t10[4], t11[4];
2212 GLfloat a, b;
2213 GLbitfield useBorderColor = 0x0;
2214
2215 clamp_rect_coord_linear(tObj->WrapS, texcoords[i][0], width,
2216 &i0, &i1, &a);
2217 clamp_rect_coord_linear(tObj->WrapT, texcoords[i][1], height,
2218 &j0, &j1, &b);
2219
2220 /* compute integer rows/columns */
2221 if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT;
2222 if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT;
2223 if (j0 < 0 || j0 >= height) useBorderColor |= J0BIT;
2224 if (j1 < 0 || j1 >= height) useBorderColor |= J1BIT;
2225
2226 /* get four texel samples */
2227 if (useBorderColor & (I0BIT | J0BIT))
2228 get_border_color(tObj, img, t00);
2229 else
2230 img->FetchTexelf(img, i0, j0, 0, t00);
2231
2232 if (useBorderColor & (I1BIT | J0BIT))
2233 get_border_color(tObj, img, t10);
2234 else
2235 img->FetchTexelf(img, i1, j0, 0, t10);
2236
2237 if (useBorderColor & (I0BIT | J1BIT))
2238 get_border_color(tObj, img, t01);
2239 else
2240 img->FetchTexelf(img, i0, j1, 0, t01);
2241
2242 if (useBorderColor & (I1BIT | J1BIT))
2243 get_border_color(tObj, img, t11);
2244 else
2245 img->FetchTexelf(img, i1, j1, 0, t11);
2246
2247 lerp_rgba_2d(rgba[i], a, b, t00, t10, t01, t11);
2248 }
2249 }
2250
2251
2252 /** Sample Rect texture, using lambda to choose between min/magnification */
2253 static void
2254 sample_lambda_rect(struct gl_context *ctx,
2255 const struct gl_texture_object *tObj, GLuint n,
2256 const GLfloat texcoords[][4], const GLfloat lambda[],
2257 GLfloat rgba[][4])
2258 {
2259 GLuint minStart, minEnd, magStart, magEnd;
2260
2261 /* We only need lambda to decide between minification and magnification.
2262 * There is no mipmapping with rectangular textures.
2263 */
2264 compute_min_mag_ranges(tObj, n, lambda,
2265 &minStart, &minEnd, &magStart, &magEnd);
2266
2267 if (minStart < minEnd) {
2268 if (tObj->MinFilter == GL_NEAREST) {
2269 sample_nearest_rect(ctx, tObj, minEnd - minStart,
2270 texcoords + minStart, NULL, rgba + minStart);
2271 }
2272 else {
2273 sample_linear_rect(ctx, tObj, minEnd - minStart,
2274 texcoords + minStart, NULL, rgba + minStart);
2275 }
2276 }
2277 if (magStart < magEnd) {
2278 if (tObj->MagFilter == GL_NEAREST) {
2279 sample_nearest_rect(ctx, tObj, magEnd - magStart,
2280 texcoords + magStart, NULL, rgba + magStart);
2281 }
2282 else {
2283 sample_linear_rect(ctx, tObj, magEnd - magStart,
2284 texcoords + magStart, NULL, rgba + magStart);
2285 }
2286 }
2287 }
2288
2289
2290 /**********************************************************************/
2291 /* 2D Texture Array Sampling Functions */
2292 /**********************************************************************/
2293
2294 /**
2295 * Return the texture sample for coordinate (s,t,r) using GL_NEAREST filter.
2296 */
2297 static void
2298 sample_2d_array_nearest(struct gl_context *ctx,
2299 const struct gl_texture_object *tObj,
2300 const struct gl_texture_image *img,
2301 const GLfloat texcoord[4],
2302 GLfloat rgba[4])
2303 {
2304 const GLint width = img->Width2; /* without border, power of two */
2305 const GLint height = img->Height2; /* without border, power of two */
2306 const GLint depth = img->Depth;
2307 GLint i, j;
2308 GLint array;
2309 (void) ctx;
2310
2311 i = nearest_texel_location(tObj->WrapS, img, width, texcoord[0]);
2312 j = nearest_texel_location(tObj->WrapT, img, height, texcoord[1]);
2313 array = tex_array_slice(texcoord[2], depth);
2314
2315 if (i < 0 || i >= (GLint) img->Width ||
2316 j < 0 || j >= (GLint) img->Height ||
2317 array < 0 || array >= (GLint) img->Depth) {
2318 /* Need this test for GL_CLAMP_TO_BORDER mode */
2319 get_border_color(tObj, img, rgba);
2320 }
2321 else {
2322 img->FetchTexelf(img, i, j, array, rgba);
2323 }
2324 }
2325
2326
2327 /**
2328 * Return the texture sample for coordinate (s,t,r) using GL_LINEAR filter.
2329 */
2330 static void
2331 sample_2d_array_linear(struct gl_context *ctx,
2332 const struct gl_texture_object *tObj,
2333 const struct gl_texture_image *img,
2334 const GLfloat texcoord[4],
2335 GLfloat rgba[4])
2336 {
2337 const GLint width = img->Width2;
2338 const GLint height = img->Height2;
2339 const GLint depth = img->Depth;
2340 GLint i0, j0, i1, j1;
2341 GLint array;
2342 GLbitfield useBorderColor = 0x0;
2343 GLfloat a, b;
2344 GLfloat t00[4], t01[4], t10[4], t11[4];
2345
2346 linear_texel_locations(tObj->WrapS, img, width, texcoord[0], &i0, &i1, &a);
2347 linear_texel_locations(tObj->WrapT, img, height, texcoord[1], &j0, &j1, &b);
2348 array = tex_array_slice(texcoord[2], depth);
2349
2350 if (array < 0 || array >= depth) {
2351 COPY_4V(rgba, tObj->BorderColor.f);
2352 }
2353 else {
2354 if (img->Border) {
2355 i0 += img->Border;
2356 i1 += img->Border;
2357 j0 += img->Border;
2358 j1 += img->Border;
2359 }
2360 else {
2361 /* check if sampling texture border color */
2362 if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT;
2363 if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT;
2364 if (j0 < 0 || j0 >= height) useBorderColor |= J0BIT;
2365 if (j1 < 0 || j1 >= height) useBorderColor |= J1BIT;
2366 }
2367
2368 /* Fetch texels */
2369 if (useBorderColor & (I0BIT | J0BIT)) {
2370 get_border_color(tObj, img, t00);
2371 }
2372 else {
2373 img->FetchTexelf(img, i0, j0, array, t00);
2374 }
2375 if (useBorderColor & (I1BIT | J0BIT)) {
2376 get_border_color(tObj, img, t10);
2377 }
2378 else {
2379 img->FetchTexelf(img, i1, j0, array, t10);
2380 }
2381 if (useBorderColor & (I0BIT | J1BIT)) {
2382 get_border_color(tObj, img, t01);
2383 }
2384 else {
2385 img->FetchTexelf(img, i0, j1, array, t01);
2386 }
2387 if (useBorderColor & (I1BIT | J1BIT)) {
2388 get_border_color(tObj, img, t11);
2389 }
2390 else {
2391 img->FetchTexelf(img, i1, j1, array, t11);
2392 }
2393
2394 /* trilinear interpolation of samples */
2395 lerp_rgba_2d(rgba, a, b, t00, t10, t01, t11);
2396 }
2397 }
2398
2399
2400 static void
2401 sample_2d_array_nearest_mipmap_nearest(struct gl_context *ctx,
2402 const struct gl_texture_object *tObj,
2403 GLuint n, const GLfloat texcoord[][4],
2404 const GLfloat lambda[], GLfloat rgba[][4])
2405 {
2406 GLuint i;
2407 for (i = 0; i < n; i++) {
2408 GLint level = nearest_mipmap_level(tObj, lambda[i]);
2409 sample_2d_array_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i],
2410 rgba[i]);
2411 }
2412 }
2413
2414
2415 static void
2416 sample_2d_array_linear_mipmap_nearest(struct gl_context *ctx,
2417 const struct gl_texture_object *tObj,
2418 GLuint n, const GLfloat texcoord[][4],
2419 const GLfloat lambda[], GLfloat rgba[][4])
2420 {
2421 GLuint i;
2422 ASSERT(lambda != NULL);
2423 for (i = 0; i < n; i++) {
2424 GLint level = nearest_mipmap_level(tObj, lambda[i]);
2425 sample_2d_array_linear(ctx, tObj, tObj->Image[0][level],
2426 texcoord[i], rgba[i]);
2427 }
2428 }
2429
2430
2431 static void
2432 sample_2d_array_nearest_mipmap_linear(struct gl_context *ctx,
2433 const struct gl_texture_object *tObj,
2434 GLuint n, const GLfloat texcoord[][4],
2435 const GLfloat lambda[], GLfloat rgba[][4])
2436 {
2437 GLuint i;
2438 ASSERT(lambda != NULL);
2439 for (i = 0; i < n; i++) {
2440 GLint level = linear_mipmap_level(tObj, lambda[i]);
2441 if (level >= tObj->_MaxLevel) {
2442 sample_2d_array_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
2443 texcoord[i], rgba[i]);
2444 }
2445 else {
2446 GLfloat t0[4], t1[4]; /* texels */
2447 const GLfloat f = FRAC(lambda[i]);
2448 sample_2d_array_nearest(ctx, tObj, tObj->Image[0][level ],
2449 texcoord[i], t0);
2450 sample_2d_array_nearest(ctx, tObj, tObj->Image[0][level+1],
2451 texcoord[i], t1);
2452 lerp_rgba(rgba[i], f, t0, t1);
2453 }
2454 }
2455 }
2456
2457
2458 static void
2459 sample_2d_array_linear_mipmap_linear(struct gl_context *ctx,
2460 const struct gl_texture_object *tObj,
2461 GLuint n, const GLfloat texcoord[][4],
2462 const GLfloat lambda[], GLfloat rgba[][4])
2463 {
2464 GLuint i;
2465 ASSERT(lambda != NULL);
2466 for (i = 0; i < n; i++) {
2467 GLint level = linear_mipmap_level(tObj, lambda[i]);
2468 if (level >= tObj->_MaxLevel) {
2469 sample_2d_array_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
2470 texcoord[i], rgba[i]);
2471 }
2472 else {
2473 GLfloat t0[4], t1[4]; /* texels */
2474 const GLfloat f = FRAC(lambda[i]);
2475 sample_2d_array_linear(ctx, tObj, tObj->Image[0][level ],
2476 texcoord[i], t0);
2477 sample_2d_array_linear(ctx, tObj, tObj->Image[0][level+1],
2478 texcoord[i], t1);
2479 lerp_rgba(rgba[i], f, t0, t1);
2480 }
2481 }
2482 }
2483
2484
2485 /** Sample 2D Array texture, nearest filtering for both min/magnification */
2486 static void
2487 sample_nearest_2d_array(struct gl_context *ctx,
2488 const struct gl_texture_object *tObj, GLuint n,
2489 const GLfloat texcoords[][4], const GLfloat lambda[],
2490 GLfloat rgba[][4])
2491 {
2492 GLuint i;
2493 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
2494 (void) lambda;
2495 for (i = 0; i < n; i++) {
2496 sample_2d_array_nearest(ctx, tObj, image, texcoords[i], rgba[i]);
2497 }
2498 }
2499
2500
2501
2502 /** Sample 2D Array texture, linear filtering for both min/magnification */
2503 static void
2504 sample_linear_2d_array(struct gl_context *ctx,
2505 const struct gl_texture_object *tObj, GLuint n,
2506 const GLfloat texcoords[][4],
2507 const GLfloat lambda[], GLfloat rgba[][4])
2508 {
2509 GLuint i;
2510 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
2511 (void) lambda;
2512 for (i = 0; i < n; i++) {
2513 sample_2d_array_linear(ctx, tObj, image, texcoords[i], rgba[i]);
2514 }
2515 }
2516
2517
2518 /** Sample 2D Array texture, using lambda to choose between min/magnification */
2519 static void
2520 sample_lambda_2d_array(struct gl_context *ctx,
2521 const struct gl_texture_object *tObj, GLuint n,
2522 const GLfloat texcoords[][4], const GLfloat lambda[],
2523 GLfloat rgba[][4])
2524 {
2525 GLuint minStart, minEnd; /* texels with minification */
2526 GLuint magStart, magEnd; /* texels with magnification */
2527 GLuint i;
2528
2529 ASSERT(lambda != NULL);
2530 compute_min_mag_ranges(tObj, n, lambda,
2531 &minStart, &minEnd, &magStart, &magEnd);
2532
2533 if (minStart < minEnd) {
2534 /* do the minified texels */
2535 GLuint m = minEnd - minStart;
2536 switch (tObj->MinFilter) {
2537 case GL_NEAREST:
2538 for (i = minStart; i < minEnd; i++)
2539 sample_2d_array_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2540 texcoords[i], rgba[i]);
2541 break;
2542 case GL_LINEAR:
2543 for (i = minStart; i < minEnd; i++)
2544 sample_2d_array_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2545 texcoords[i], rgba[i]);
2546 break;
2547 case GL_NEAREST_MIPMAP_NEAREST:
2548 sample_2d_array_nearest_mipmap_nearest(ctx, tObj, m,
2549 texcoords + minStart,
2550 lambda + minStart,
2551 rgba + minStart);
2552 break;
2553 case GL_LINEAR_MIPMAP_NEAREST:
2554 sample_2d_array_linear_mipmap_nearest(ctx, tObj, m,
2555 texcoords + minStart,
2556 lambda + minStart,
2557 rgba + minStart);
2558 break;
2559 case GL_NEAREST_MIPMAP_LINEAR:
2560 sample_2d_array_nearest_mipmap_linear(ctx, tObj, m,
2561 texcoords + minStart,
2562 lambda + minStart,
2563 rgba + minStart);
2564 break;
2565 case GL_LINEAR_MIPMAP_LINEAR:
2566 sample_2d_array_linear_mipmap_linear(ctx, tObj, m,
2567 texcoords + minStart,
2568 lambda + minStart,
2569 rgba + minStart);
2570 break;
2571 default:
2572 _mesa_problem(ctx, "Bad min filter in sample_2d_array_texture");
2573 return;
2574 }
2575 }
2576
2577 if (magStart < magEnd) {
2578 /* do the magnified texels */
2579 switch (tObj->MagFilter) {
2580 case GL_NEAREST:
2581 for (i = magStart; i < magEnd; i++)
2582 sample_2d_array_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2583 texcoords[i], rgba[i]);
2584 break;
2585 case GL_LINEAR:
2586 for (i = magStart; i < magEnd; i++)
2587 sample_2d_array_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2588 texcoords[i], rgba[i]);
2589 break;
2590 default:
2591 _mesa_problem(ctx, "Bad mag filter in sample_2d_array_texture");
2592 return;
2593 }
2594 }
2595 }
2596
2597
2598
2599
2600 /**********************************************************************/
2601 /* 1D Texture Array Sampling Functions */
2602 /**********************************************************************/
2603
2604 /**
2605 * Return the texture sample for coordinate (s,t,r) using GL_NEAREST filter.
2606 */
2607 static void
2608 sample_1d_array_nearest(struct gl_context *ctx,
2609 const struct gl_texture_object *tObj,
2610 const struct gl_texture_image *img,
2611 const GLfloat texcoord[4],
2612 GLfloat rgba[4])
2613 {
2614 const GLint width = img->Width2; /* without border, power of two */
2615 const GLint height = img->Height;
2616 GLint i;
2617 GLint array;
2618 (void) ctx;
2619
2620 i = nearest_texel_location(tObj->WrapS, img, width, texcoord[0]);
2621 array = tex_array_slice(texcoord[1], height);
2622
2623 if (i < 0 || i >= (GLint) img->Width ||
2624 array < 0 || array >= (GLint) img->Height) {
2625 /* Need this test for GL_CLAMP_TO_BORDER mode */
2626 get_border_color(tObj, img, rgba);
2627 }
2628 else {
2629 img->FetchTexelf(img, i, array, 0, rgba);
2630 }
2631 }
2632
2633
2634 /**
2635 * Return the texture sample for coordinate (s,t,r) using GL_LINEAR filter.
2636 */
2637 static void
2638 sample_1d_array_linear(struct gl_context *ctx,
2639 const struct gl_texture_object *tObj,
2640 const struct gl_texture_image *img,
2641 const GLfloat texcoord[4],
2642 GLfloat rgba[4])
2643 {
2644 const GLint width = img->Width2;
2645 const GLint height = img->Height;
2646 GLint i0, i1;
2647 GLint array;
2648 GLbitfield useBorderColor = 0x0;
2649 GLfloat a;
2650 GLfloat t0[4], t1[4];
2651
2652 linear_texel_locations(tObj->WrapS, img, width, texcoord[0], &i0, &i1, &a);
2653 array = tex_array_slice(texcoord[1], height);
2654
2655 if (img->Border) {
2656 i0 += img->Border;
2657 i1 += img->Border;
2658 }
2659 else {
2660 /* check if sampling texture border color */
2661 if (i0 < 0 || i0 >= width) useBorderColor |= I0BIT;
2662 if (i1 < 0 || i1 >= width) useBorderColor |= I1BIT;
2663 }
2664
2665 if (array < 0 || array >= height) useBorderColor |= K0BIT;
2666
2667 /* Fetch texels */
2668 if (useBorderColor & (I0BIT | K0BIT)) {
2669 get_border_color(tObj, img, t0);
2670 }
2671 else {
2672 img->FetchTexelf(img, i0, array, 0, t0);
2673 }
2674 if (useBorderColor & (I1BIT | K0BIT)) {
2675 get_border_color(tObj, img, t1);
2676 }
2677 else {
2678 img->FetchTexelf(img, i1, array, 0, t1);
2679 }
2680
2681 /* bilinear interpolation of samples */
2682 lerp_rgba(rgba, a, t0, t1);
2683 }
2684
2685
2686 static void
2687 sample_1d_array_nearest_mipmap_nearest(struct gl_context *ctx,
2688 const struct gl_texture_object *tObj,
2689 GLuint n, const GLfloat texcoord[][4],
2690 const GLfloat lambda[], GLfloat rgba[][4])
2691 {
2692 GLuint i;
2693 for (i = 0; i < n; i++) {
2694 GLint level = nearest_mipmap_level(tObj, lambda[i]);
2695 sample_1d_array_nearest(ctx, tObj, tObj->Image[0][level], texcoord[i],
2696 rgba[i]);
2697 }
2698 }
2699
2700
2701 static void
2702 sample_1d_array_linear_mipmap_nearest(struct gl_context *ctx,
2703 const struct gl_texture_object *tObj,
2704 GLuint n, const GLfloat texcoord[][4],
2705 const GLfloat lambda[], GLfloat rgba[][4])
2706 {
2707 GLuint i;
2708 ASSERT(lambda != NULL);
2709 for (i = 0; i < n; i++) {
2710 GLint level = nearest_mipmap_level(tObj, lambda[i]);
2711 sample_1d_array_linear(ctx, tObj, tObj->Image[0][level],
2712 texcoord[i], rgba[i]);
2713 }
2714 }
2715
2716
2717 static void
2718 sample_1d_array_nearest_mipmap_linear(struct gl_context *ctx,
2719 const struct gl_texture_object *tObj,
2720 GLuint n, const GLfloat texcoord[][4],
2721 const GLfloat lambda[], GLfloat rgba[][4])
2722 {
2723 GLuint i;
2724 ASSERT(lambda != NULL);
2725 for (i = 0; i < n; i++) {
2726 GLint level = linear_mipmap_level(tObj, lambda[i]);
2727 if (level >= tObj->_MaxLevel) {
2728 sample_1d_array_nearest(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
2729 texcoord[i], rgba[i]);
2730 }
2731 else {
2732 GLfloat t0[4], t1[4]; /* texels */
2733 const GLfloat f = FRAC(lambda[i]);
2734 sample_1d_array_nearest(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
2735 sample_1d_array_nearest(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
2736 lerp_rgba(rgba[i], f, t0, t1);
2737 }
2738 }
2739 }
2740
2741
2742 static void
2743 sample_1d_array_linear_mipmap_linear(struct gl_context *ctx,
2744 const struct gl_texture_object *tObj,
2745 GLuint n, const GLfloat texcoord[][4],
2746 const GLfloat lambda[], GLfloat rgba[][4])
2747 {
2748 GLuint i;
2749 ASSERT(lambda != NULL);
2750 for (i = 0; i < n; i++) {
2751 GLint level = linear_mipmap_level(tObj, lambda[i]);
2752 if (level >= tObj->_MaxLevel) {
2753 sample_1d_array_linear(ctx, tObj, tObj->Image[0][tObj->_MaxLevel],
2754 texcoord[i], rgba[i]);
2755 }
2756 else {
2757 GLfloat t0[4], t1[4]; /* texels */
2758 const GLfloat f = FRAC(lambda[i]);
2759 sample_1d_array_linear(ctx, tObj, tObj->Image[0][level ], texcoord[i], t0);
2760 sample_1d_array_linear(ctx, tObj, tObj->Image[0][level+1], texcoord[i], t1);
2761 lerp_rgba(rgba[i], f, t0, t1);
2762 }
2763 }
2764 }
2765
2766
2767 /** Sample 1D Array texture, nearest filtering for both min/magnification */
2768 static void
2769 sample_nearest_1d_array(struct gl_context *ctx,
2770 const struct gl_texture_object *tObj, GLuint n,
2771 const GLfloat texcoords[][4], const GLfloat lambda[],
2772 GLfloat rgba[][4])
2773 {
2774 GLuint i;
2775 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
2776 (void) lambda;
2777 for (i = 0; i < n; i++) {
2778 sample_1d_array_nearest(ctx, tObj, image, texcoords[i], rgba[i]);
2779 }
2780 }
2781
2782
2783 /** Sample 1D Array texture, linear filtering for both min/magnification */
2784 static void
2785 sample_linear_1d_array(struct gl_context *ctx,
2786 const struct gl_texture_object *tObj, GLuint n,
2787 const GLfloat texcoords[][4],
2788 const GLfloat lambda[], GLfloat rgba[][4])
2789 {
2790 GLuint i;
2791 struct gl_texture_image *image = tObj->Image[0][tObj->BaseLevel];
2792 (void) lambda;
2793 for (i = 0; i < n; i++) {
2794 sample_1d_array_linear(ctx, tObj, image, texcoords[i], rgba[i]);
2795 }
2796 }
2797
2798
2799 /** Sample 1D Array texture, using lambda to choose between min/magnification */
2800 static void
2801 sample_lambda_1d_array(struct gl_context *ctx,
2802 const struct gl_texture_object *tObj, GLuint n,
2803 const GLfloat texcoords[][4], const GLfloat lambda[],
2804 GLfloat rgba[][4])
2805 {
2806 GLuint minStart, minEnd; /* texels with minification */
2807 GLuint magStart, magEnd; /* texels with magnification */
2808 GLuint i;
2809
2810 ASSERT(lambda != NULL);
2811 compute_min_mag_ranges(tObj, n, lambda,
2812 &minStart, &minEnd, &magStart, &magEnd);
2813
2814 if (minStart < minEnd) {
2815 /* do the minified texels */
2816 GLuint m = minEnd - minStart;
2817 switch (tObj->MinFilter) {
2818 case GL_NEAREST:
2819 for (i = minStart; i < minEnd; i++)
2820 sample_1d_array_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2821 texcoords[i], rgba[i]);
2822 break;
2823 case GL_LINEAR:
2824 for (i = minStart; i < minEnd; i++)
2825 sample_1d_array_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2826 texcoords[i], rgba[i]);
2827 break;
2828 case GL_NEAREST_MIPMAP_NEAREST:
2829 sample_1d_array_nearest_mipmap_nearest(ctx, tObj, m, texcoords + minStart,
2830 lambda + minStart, rgba + minStart);
2831 break;
2832 case GL_LINEAR_MIPMAP_NEAREST:
2833 sample_1d_array_linear_mipmap_nearest(ctx, tObj, m,
2834 texcoords + minStart,
2835 lambda + minStart,
2836 rgba + minStart);
2837 break;
2838 case GL_NEAREST_MIPMAP_LINEAR:
2839 sample_1d_array_nearest_mipmap_linear(ctx, tObj, m, texcoords + minStart,
2840 lambda + minStart, rgba + minStart);
2841 break;
2842 case GL_LINEAR_MIPMAP_LINEAR:
2843 sample_1d_array_linear_mipmap_linear(ctx, tObj, m,
2844 texcoords + minStart,
2845 lambda + minStart,
2846 rgba + minStart);
2847 break;
2848 default:
2849 _mesa_problem(ctx, "Bad min filter in sample_1d_array_texture");
2850 return;
2851 }
2852 }
2853
2854 if (magStart < magEnd) {
2855 /* do the magnified texels */
2856 switch (tObj->MagFilter) {
2857 case GL_NEAREST:
2858 for (i = magStart; i < magEnd; i++)
2859 sample_1d_array_nearest(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2860 texcoords[i], rgba[i]);
2861 break;
2862 case GL_LINEAR:
2863 for (i = magStart; i < magEnd; i++)
2864 sample_1d_array_linear(ctx, tObj, tObj->Image[0][tObj->BaseLevel],
2865 texcoords[i], rgba[i]);
2866 break;
2867 default:
2868 _mesa_problem(ctx, "Bad mag filter in sample_1d_array_texture");
2869 return;
2870 }
2871 }
2872 }
2873
2874
2875 /**
2876 * Compare texcoord against depth sample. Return 1.0 or the ambient value.
2877 */
2878 static INLINE GLfloat
2879 shadow_compare(GLenum function, GLfloat coord, GLfloat depthSample,
2880 GLfloat ambient)
2881 {
2882 switch (function) {
2883 case GL_LEQUAL:
2884 return (coord <= depthSample) ? 1.0F : ambient;
2885 case GL_GEQUAL:
2886 return (coord >= depthSample) ? 1.0F : ambient;
2887 case GL_LESS:
2888 return (coord < depthSample) ? 1.0F : ambient;
2889 case GL_GREATER:
2890 return (coord > depthSample) ? 1.0F : ambient;
2891 case GL_EQUAL:
2892 return (coord == depthSample) ? 1.0F : ambient;
2893 case GL_NOTEQUAL:
2894 return (coord != depthSample) ? 1.0F : ambient;
2895 case GL_ALWAYS:
2896 return 1.0F;
2897 case GL_NEVER:
2898 return ambient;
2899 case GL_NONE:
2900 return depthSample;
2901 default:
2902 _mesa_problem(NULL, "Bad compare func in shadow_compare");
2903 return ambient;
2904 }
2905 }
2906
2907
2908 /**
2909 * Compare texcoord against four depth samples.
2910 */
2911 static INLINE GLfloat
2912 shadow_compare4(GLenum function, GLfloat coord,
2913 GLfloat depth00, GLfloat depth01,
2914 GLfloat depth10, GLfloat depth11,
2915 GLfloat ambient, GLfloat wi, GLfloat wj)
2916 {
2917 const GLfloat d = (1.0F - (GLfloat) ambient) * 0.25F;
2918 GLfloat luminance = 1.0F;
2919
2920 switch (function) {
2921 case GL_LEQUAL:
2922 if (depth00 <= coord) luminance -= d;
2923 if (depth01 <= coord) luminance -= d;
2924 if (depth10 <= coord) luminance -= d;
2925 if (depth11 <= coord) luminance -= d;
2926 return luminance;
2927 case GL_GEQUAL:
2928 if (depth00 >= coord) luminance -= d;
2929 if (depth01 >= coord) luminance -= d;
2930 if (depth10 >= coord) luminance -= d;
2931 if (depth11 >= coord) luminance -= d;
2932 return luminance;
2933 case GL_LESS:
2934 if (depth00 < coord) luminance -= d;
2935 if (depth01 < coord) luminance -= d;
2936 if (depth10 < coord) luminance -= d;
2937 if (depth11 < coord) luminance -= d;
2938 return luminance;
2939 case GL_GREATER:
2940 if (depth00 > coord) luminance -= d;
2941 if (depth01 > coord) luminance -= d;
2942 if (depth10 > coord) luminance -= d;
2943 if (depth11 > coord) luminance -= d;
2944 return luminance;
2945 case GL_EQUAL:
2946 if (depth00 == coord) luminance -= d;
2947 if (depth01 == coord) luminance -= d;
2948 if (depth10 == coord) luminance -= d;
2949 if (depth11 == coord) luminance -= d;
2950 return luminance;
2951 case GL_NOTEQUAL:
2952 if (depth00 != coord) luminance -= d;
2953 if (depth01 != coord) luminance -= d;
2954 if (depth10 != coord) luminance -= d;
2955 if (depth11 != coord) luminance -= d;
2956 return luminance;
2957 case GL_ALWAYS:
2958 return 0.0;
2959 case GL_NEVER:
2960 return ambient;
2961 case GL_NONE:
2962 /* ordinary bilinear filtering */
2963 return lerp_2d(wi, wj, depth00, depth10, depth01, depth11);
2964 default:
2965 _mesa_problem(NULL, "Bad compare func in sample_depth_texture");
2966 return 0.0F;
2967 }
2968 }
2969
2970
2971 /**
2972 * Choose the mipmap level to use when sampling from a depth texture.
2973 */
2974 static int
2975 choose_depth_texture_level(const struct gl_texture_object *tObj, GLfloat lambda)
2976 {
2977 GLint level;
2978
2979 if (tObj->MinFilter == GL_NEAREST || tObj->MinFilter == GL_LINEAR) {
2980 /* no mipmapping - use base level */
2981 level = tObj->BaseLevel;
2982 }
2983 else {
2984 /* choose mipmap level */
2985 lambda = CLAMP(lambda, tObj->MinLod, tObj->MaxLod);
2986 level = (GLint) lambda;
2987 level = CLAMP(level, tObj->BaseLevel, tObj->_MaxLevel);
2988 }
2989
2990 return level;
2991 }
2992
2993
2994 /**
2995 * Sample a shadow/depth texture. This function is incomplete. It doesn't
2996 * check for minification vs. magnification, etc.
2997 */
2998 static void
2999 sample_depth_texture( struct gl_context *ctx,
3000 const struct gl_texture_object *tObj, GLuint n,
3001 const GLfloat texcoords[][4], const GLfloat lambda[],
3002 GLfloat texel[][4] )
3003 {
3004 const GLint level = choose_depth_texture_level(tObj, lambda[0]);
3005 const struct gl_texture_image *img = tObj->Image[0][level];
3006 const GLint width = img->Width;
3007 const GLint height = img->Height;
3008 const GLint depth = img->Depth;
3009 const GLuint compare_coord = (tObj->Target == GL_TEXTURE_2D_ARRAY_EXT)
3010 ? 3 : 2;
3011 GLfloat ambient;
3012 GLenum function;
3013 GLfloat result;
3014
3015 ASSERT(img->_BaseFormat == GL_DEPTH_COMPONENT ||
3016 img->_BaseFormat == GL_DEPTH_STENCIL_EXT);
3017
3018 ASSERT(tObj->Target == GL_TEXTURE_1D ||
3019 tObj->Target == GL_TEXTURE_2D ||
3020 tObj->Target == GL_TEXTURE_RECTANGLE_NV ||
3021 tObj->Target == GL_TEXTURE_1D_ARRAY_EXT ||
3022 tObj->Target == GL_TEXTURE_2D_ARRAY_EXT);
3023
3024 ambient = tObj->CompareFailValue;
3025
3026 /* XXXX if tObj->MinFilter != tObj->MagFilter, we're ignoring lambda */
3027
3028 function = (tObj->CompareMode == GL_COMPARE_R_TO_TEXTURE_ARB) ?
3029 tObj->CompareFunc : GL_NONE;
3030
3031 if (tObj->MagFilter == GL_NEAREST) {
3032 GLuint i;
3033 for (i = 0; i < n; i++) {
3034 GLfloat depthSample;
3035 GLint col, row, slice;
3036
3037 nearest_texcoord(tObj, level, texcoords[i], &col, &row, &slice);
3038
3039 if (col >= 0 && row >= 0 && col < width && row < height &&
3040 slice >= 0 && slice < depth) {
3041 img->FetchTexelf(img, col, row, slice, &depthSample);
3042 }
3043 else {
3044 depthSample = tObj->BorderColor.f[0];
3045 }
3046
3047 result = shadow_compare(function, texcoords[i][compare_coord],
3048 depthSample, ambient);
3049
3050 switch (tObj->DepthMode) {
3051 case GL_LUMINANCE:
3052 ASSIGN_4V(texel[i], result, result, result, 1.0F);
3053 break;
3054 case GL_INTENSITY:
3055 ASSIGN_4V(texel[i], result, result, result, result);
3056 break;
3057 case GL_ALPHA:
3058 ASSIGN_4V(texel[i], 0.0F, 0.0F, 0.0F, result);
3059 break;
3060 case GL_RED:
3061 ASSIGN_4V(texel[i], result, 0.0F, 0.0F, 1.0F);
3062 break;
3063 default:
3064 _mesa_problem(ctx, "Bad depth texture mode");
3065 }
3066 }
3067 }
3068 else {
3069 GLuint i;
3070 ASSERT(tObj->MagFilter == GL_LINEAR);
3071 for (i = 0; i < n; i++) {
3072 GLfloat depth00, depth01, depth10, depth11;
3073 GLint i0, i1, j0, j1;
3074 GLint slice;
3075 GLfloat wi, wj;
3076 GLuint useBorderTexel;
3077
3078 linear_texcoord(tObj, level, texcoords[i], &i0, &i1, &j0, &j1, &slice,
3079 &wi, &wj);
3080
3081 useBorderTexel = 0;
3082 if (img->Border) {
3083 i0 += img->Border;
3084 i1 += img->Border;
3085 if (tObj->Target != GL_TEXTURE_1D_ARRAY_EXT) {
3086 j0 += img->Border;
3087 j1 += img->Border;
3088 }
3089 }
3090 else {
3091 if (i0 < 0 || i0 >= (GLint) width) useBorderTexel |= I0BIT;
3092 if (i1 < 0 || i1 >= (GLint) width) useBorderTexel |= I1BIT;
3093 if (j0 < 0 || j0 >= (GLint) height) useBorderTexel |= J0BIT;
3094 if (j1 < 0 || j1 >= (GLint) height) useBorderTexel |= J1BIT;
3095 }
3096
3097 if (slice < 0 || slice >= (GLint) depth) {
3098 depth00 = tObj->BorderColor.f[0];
3099 depth01 = tObj->BorderColor.f[0];
3100 depth10 = tObj->BorderColor.f[0];
3101 depth11 = tObj->BorderColor.f[0];
3102 }
3103 else {
3104 /* get four depth samples from the texture */
3105 if (useBorderTexel & (I0BIT | J0BIT)) {
3106 depth00 = tObj->BorderColor.f[0];
3107 }
3108 else {
3109 img->FetchTexelf(img, i0, j0, slice, &depth00);
3110 }
3111 if (useBorderTexel & (I1BIT | J0BIT)) {
3112 depth10 = tObj->BorderColor.f[0];
3113 }
3114 else {
3115 img->FetchTexelf(img, i1, j0, slice, &depth10);
3116 }
3117
3118 if (tObj->Target != GL_TEXTURE_1D_ARRAY_EXT) {
3119 if (useBorderTexel & (I0BIT | J1BIT)) {
3120 depth01 = tObj->BorderColor.f[0];
3121 }
3122 else {
3123 img->FetchTexelf(img, i0, j1, slice, &depth01);
3124 }
3125 if (useBorderTexel & (I1BIT | J1BIT)) {
3126 depth11 = tObj->BorderColor.f[0];
3127 }
3128 else {
3129 img->FetchTexelf(img, i1, j1, slice, &depth11);
3130 }
3131 }
3132 else {
3133 depth01 = depth00;
3134 depth11 = depth10;
3135 }
3136 }
3137
3138 result = shadow_compare4(function, texcoords[i][compare_coord],
3139 depth00, depth01, depth10, depth11,
3140 ambient, wi, wj);
3141
3142 switch (tObj->DepthMode) {
3143 case GL_LUMINANCE:
3144 ASSIGN_4V(texel[i], result, result, result, 1.0F);
3145 break;
3146 case GL_INTENSITY:
3147 ASSIGN_4V(texel[i], result, result, result, result);
3148 break;
3149 case GL_ALPHA:
3150 ASSIGN_4V(texel[i], 0.0F, 0.0F, 0.0F, result);
3151 break;
3152 default:
3153 _mesa_problem(ctx, "Bad depth texture mode");
3154 }
3155
3156 } /* for */
3157 } /* if filter */
3158 }
3159
3160
3161 /**
3162 * We use this function when a texture object is in an "incomplete" state.
3163 * When a fragment program attempts to sample an incomplete texture we
3164 * return black (see issue 23 in GL_ARB_fragment_program spec).
3165 * Note: fragment programs don't observe the texture enable/disable flags.
3166 */
3167 static void
3168 null_sample_func( struct gl_context *ctx,
3169 const struct gl_texture_object *tObj, GLuint n,
3170 const GLfloat texcoords[][4], const GLfloat lambda[],
3171 GLfloat rgba[][4])
3172 {
3173 GLuint i;
3174 (void) ctx;
3175 (void) tObj;
3176 (void) texcoords;
3177 (void) lambda;
3178 for (i = 0; i < n; i++) {
3179 rgba[i][RCOMP] = 0;
3180 rgba[i][GCOMP] = 0;
3181 rgba[i][BCOMP] = 0;
3182 rgba[i][ACOMP] = 1.0;
3183 }
3184 }
3185
3186
3187 /**
3188 * Choose the texture sampling function for the given texture object.
3189 */
3190 texture_sample_func
3191 _swrast_choose_texture_sample_func( struct gl_context *ctx,
3192 const struct gl_texture_object *t )
3193 {
3194 if (!t || !t->_Complete) {
3195 return &null_sample_func;
3196 }
3197 else {
3198 const GLboolean needLambda = (GLboolean) (t->MinFilter != t->MagFilter);
3199 const GLenum format = t->Image[0][t->BaseLevel]->_BaseFormat;
3200
3201 switch (t->Target) {
3202 case GL_TEXTURE_1D:
3203 if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL_EXT) {
3204 return &sample_depth_texture;
3205 }
3206 else if (needLambda) {
3207 return &sample_lambda_1d;
3208 }
3209 else if (t->MinFilter == GL_LINEAR) {
3210 return &sample_linear_1d;
3211 }
3212 else {
3213 ASSERT(t->MinFilter == GL_NEAREST);
3214 return &sample_nearest_1d;
3215 }
3216 case GL_TEXTURE_2D:
3217 if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL_EXT) {
3218 return &sample_depth_texture;
3219 }
3220 else if (needLambda) {
3221 return &sample_lambda_2d;
3222 }
3223 else if (t->MinFilter == GL_LINEAR) {
3224 return &sample_linear_2d;
3225 }
3226 else {
3227 /* check for a few optimized cases */
3228 const struct gl_texture_image *img = t->Image[0][t->BaseLevel];
3229 ASSERT(t->MinFilter == GL_NEAREST);
3230 if (t->WrapS == GL_REPEAT &&
3231 t->WrapT == GL_REPEAT &&
3232 img->_IsPowerOfTwo &&
3233 img->Border == 0 &&
3234 img->TexFormat == MESA_FORMAT_RGB888) {
3235 return &opt_sample_rgb_2d;
3236 }
3237 else if (t->WrapS == GL_REPEAT &&
3238 t->WrapT == GL_REPEAT &&
3239 img->_IsPowerOfTwo &&
3240 img->Border == 0 &&
3241 img->TexFormat == MESA_FORMAT_RGBA8888) {
3242 return &opt_sample_rgba_2d;
3243 }
3244 else {
3245 return &sample_nearest_2d;
3246 }
3247 }
3248 case GL_TEXTURE_3D:
3249 if (needLambda) {
3250 return &sample_lambda_3d;
3251 }
3252 else if (t->MinFilter == GL_LINEAR) {
3253 return &sample_linear_3d;
3254 }
3255 else {
3256 ASSERT(t->MinFilter == GL_NEAREST);
3257 return &sample_nearest_3d;
3258 }
3259 case GL_TEXTURE_CUBE_MAP:
3260 if (needLambda) {
3261 return &sample_lambda_cube;
3262 }
3263 else if (t->MinFilter == GL_LINEAR) {
3264 return &sample_linear_cube;
3265 }
3266 else {
3267 ASSERT(t->MinFilter == GL_NEAREST);
3268 return &sample_nearest_cube;
3269 }
3270 case GL_TEXTURE_RECTANGLE_NV:
3271 if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL_EXT) {
3272 return &sample_depth_texture;
3273 }
3274 else if (needLambda) {
3275 return &sample_lambda_rect;
3276 }
3277 else if (t->MinFilter == GL_LINEAR) {
3278 return &sample_linear_rect;
3279 }
3280 else {
3281 ASSERT(t->MinFilter == GL_NEAREST);
3282 return &sample_nearest_rect;
3283 }
3284 case GL_TEXTURE_1D_ARRAY_EXT:
3285 if (needLambda) {
3286 return &sample_lambda_1d_array;
3287 }
3288 else if (t->MinFilter == GL_LINEAR) {
3289 return &sample_linear_1d_array;
3290 }
3291 else {
3292 ASSERT(t->MinFilter == GL_NEAREST);
3293 return &sample_nearest_1d_array;
3294 }
3295 case GL_TEXTURE_2D_ARRAY_EXT:
3296 if (needLambda) {
3297 return &sample_lambda_2d_array;
3298 }
3299 else if (t->MinFilter == GL_LINEAR) {
3300 return &sample_linear_2d_array;
3301 }
3302 else {
3303 ASSERT(t->MinFilter == GL_NEAREST);
3304 return &sample_nearest_2d_array;
3305 }
3306 default:
3307 _mesa_problem(ctx,
3308 "invalid target in _swrast_choose_texture_sample_func");
3309 return &null_sample_func;
3310 }
3311 }
3312 }