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swrast: remove MAX_WIDTH arrays in s_depth.c
[mesa.git] / src / mesa / swrast / s_depth.c
1 /*
2 * Mesa 3-D graphics library
3 * Version: 7.2.1
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/formats.h"
29 #include "main/format_unpack.h"
30 #include "main/format_pack.h"
31 #include "main/macros.h"
32 #include "main/imports.h"
33
34 #include "s_context.h"
35 #include "s_depth.h"
36 #include "s_span.h"
37
38
39
40 #define Z_TEST(COMPARE) \
41 do { \
42 GLuint i; \
43 for (i = 0; i < n; i++) { \
44 if (mask[i]) { \
45 if (COMPARE) { \
46 /* pass */ \
47 if (write) { \
48 zbuffer[i] = zfrag[i]; \
49 } \
50 passed++; \
51 } \
52 else { \
53 /* fail */ \
54 mask[i] = 0; \
55 } \
56 } \
57 } \
58 } while (0)
59
60
61 /**
62 * Do depth test for an array of 16-bit Z values.
63 * @param zbuffer array of Z buffer values (16-bit)
64 * @param zfrag array of fragment Z values (use 16-bit in 32-bit uint)
65 * @param mask which fragments are alive, killed afterward
66 * @return number of fragments which pass the test.
67 */
68 static GLuint
69 depth_test_span16( struct gl_context *ctx, GLuint n,
70 GLushort zbuffer[], const GLuint zfrag[], GLubyte mask[] )
71 {
72 const GLboolean write = ctx->Depth.Mask;
73 GLuint passed = 0;
74
75 /* switch cases ordered from most frequent to less frequent */
76 switch (ctx->Depth.Func) {
77 case GL_LESS:
78 Z_TEST(zfrag[i] < zbuffer[i]);
79 break;
80 case GL_LEQUAL:
81 Z_TEST(zfrag[i] <= zbuffer[i]);
82 break;
83 case GL_GEQUAL:
84 Z_TEST(zfrag[i] >= zbuffer[i]);
85 break;
86 case GL_GREATER:
87 Z_TEST(zfrag[i] > zbuffer[i]);
88 break;
89 case GL_NOTEQUAL:
90 Z_TEST(zfrag[i] != zbuffer[i]);
91 break;
92 case GL_EQUAL:
93 Z_TEST(zfrag[i] == zbuffer[i]);
94 break;
95 case GL_ALWAYS:
96 Z_TEST(1);
97 break;
98 case GL_NEVER:
99 memset(mask, 0, n * sizeof(GLubyte));
100 break;
101 default:
102 _mesa_problem(ctx, "Bad depth func in depth_test_span16");
103 }
104
105 return passed;
106 }
107
108
109 /**
110 * Do depth test for an array of 32-bit Z values.
111 * @param zbuffer array of Z buffer values (32-bit)
112 * @param zfrag array of fragment Z values (use 32-bits in 32-bit uint)
113 * @param mask which fragments are alive, killed afterward
114 * @return number of fragments which pass the test.
115 */
116 static GLuint
117 depth_test_span32( struct gl_context *ctx, GLuint n,
118 GLuint zbuffer[], const GLuint zfrag[], GLubyte mask[])
119 {
120 const GLboolean write = ctx->Depth.Mask;
121 GLuint passed = 0;
122
123 /* switch cases ordered from most frequent to less frequent */
124 switch (ctx->Depth.Func) {
125 case GL_LESS:
126 Z_TEST(zfrag[i] < zbuffer[i]);
127 break;
128 case GL_LEQUAL:
129 Z_TEST(zfrag[i] <= zbuffer[i]);
130 break;
131 case GL_GEQUAL:
132 Z_TEST(zfrag[i] >= zbuffer[i]);
133 break;
134 case GL_GREATER:
135 Z_TEST(zfrag[i] > zbuffer[i]);
136 break;
137 case GL_NOTEQUAL:
138 Z_TEST(zfrag[i] != zbuffer[i]);
139 break;
140 case GL_EQUAL:
141 Z_TEST(zfrag[i] == zbuffer[i]);
142 break;
143 case GL_ALWAYS:
144 Z_TEST(1);
145 break;
146 case GL_NEVER:
147 memset(mask, 0, n * sizeof(GLubyte));
148 break;
149 default:
150 _mesa_problem(ctx, "Bad depth func in depth_test_span32");
151 }
152
153 return passed;
154 }
155
156
157 /**
158 * Clamp fragment Z values to the depth near/far range (glDepthRange()).
159 * This is used when GL_ARB_depth_clamp/GL_DEPTH_CLAMP is turned on.
160 * In that case, vertexes are not clipped against the near/far planes
161 * so rasterization will produce fragment Z values outside the usual
162 * [0,1] range.
163 */
164 void
165 _swrast_depth_clamp_span( struct gl_context *ctx, SWspan *span )
166 {
167 struct gl_framebuffer *fb = ctx->DrawBuffer;
168 const GLuint count = span->end;
169 GLint *zValues = (GLint *) span->array->z; /* sign change */
170 GLint min, max;
171 GLfloat min_f, max_f;
172 GLuint i;
173
174 if (ctx->Viewport.Near < ctx->Viewport.Far) {
175 min_f = ctx->Viewport.Near;
176 max_f = ctx->Viewport.Far;
177 } else {
178 min_f = ctx->Viewport.Far;
179 max_f = ctx->Viewport.Near;
180 }
181
182 /* Convert floating point values in [0,1] to device Z coordinates in
183 * [0, DepthMax].
184 * ex: If the Z buffer has 24 bits, DepthMax = 0xffffff.
185 *
186 * XXX this all falls apart if we have 31 or more bits of Z because
187 * the triangle rasterization code produces unsigned Z values. Negative
188 * vertex Z values come out as large fragment Z uints.
189 */
190 min = (GLint) (min_f * fb->_DepthMaxF);
191 max = (GLint) (max_f * fb->_DepthMaxF);
192 if (max < 0)
193 max = 0x7fffffff; /* catch over flow for 30-bit z */
194
195 /* Note that we do the comparisons here using signed integers.
196 */
197 for (i = 0; i < count; i++) {
198 if (zValues[i] < min)
199 zValues[i] = min;
200 if (zValues[i] > max)
201 zValues[i] = max;
202 }
203 }
204
205
206 /**
207 * Get array of 32-bit z values from the depth buffer. With clipping.
208 * Note: the returned values are always in the range [0, 2^32-1].
209 */
210 static void
211 get_z32_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
212 GLuint count, const GLint x[], const GLint y[],
213 GLuint zbuffer[])
214 {
215 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
216 const GLint w = rb->Width, h = rb->Height;
217 const GLubyte *map = _swrast_pixel_address(rb, 0, 0);
218 GLuint i;
219
220 if (rb->Format == MESA_FORMAT_Z32) {
221 const GLint rowStride = srb->RowStride;
222 for (i = 0; i < count; i++) {
223 if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
224 zbuffer[i] = *((GLuint *) (map + y[i] * rowStride + x[i] * 4));
225 }
226 }
227 }
228 else {
229 const GLint bpp = _mesa_get_format_bytes(rb->Format);
230 const GLint rowStride = srb->RowStride;
231 for (i = 0; i < count; i++) {
232 if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
233 const GLubyte *src = map + y[i] * rowStride+ x[i] * bpp;
234 _mesa_unpack_uint_z_row(rb->Format, 1, src, &zbuffer[i]);
235 }
236 }
237 }
238 }
239
240
241 /**
242 * Put an array of 32-bit z values into the depth buffer.
243 * Note: the z values are always in the range [0, 2^32-1].
244 */
245 static void
246 put_z32_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
247 GLuint count, const GLint x[], const GLint y[],
248 const GLuint zvalues[], const GLubyte mask[])
249 {
250 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
251 const GLint w = rb->Width, h = rb->Height;
252 GLubyte *map = _swrast_pixel_address(rb, 0, 0);
253 GLuint i;
254
255 if (rb->Format == MESA_FORMAT_Z32) {
256 const GLint rowStride = srb->RowStride;
257 for (i = 0; i < count; i++) {
258 if (mask[i] && x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
259 GLuint *dst = (GLuint *) (map + y[i] * rowStride + x[i] * 4);
260 *dst = zvalues[i];
261 }
262 }
263 }
264 else {
265 gl_pack_uint_z_func packZ = _mesa_get_pack_uint_z_func(rb->Format);
266 const GLint bpp = _mesa_get_format_bytes(rb->Format);
267 const GLint rowStride = srb->RowStride;
268 for (i = 0; i < count; i++) {
269 if (mask[i] && x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
270 void *dst = map + y[i] * rowStride + x[i] * bpp;
271 packZ(zvalues + i, dst);
272 }
273 }
274 }
275 }
276
277
278 /**
279 * Apply depth (Z) buffer testing to the span.
280 * \return approx number of pixels that passed (only zero is reliable)
281 */
282 GLuint
283 _swrast_depth_test_span(struct gl_context *ctx, SWspan *span)
284 {
285 struct gl_framebuffer *fb = ctx->DrawBuffer;
286 struct gl_renderbuffer *rb = fb->Attachment[BUFFER_DEPTH].Renderbuffer;
287 const GLint bpp = _mesa_get_format_bytes(rb->Format);
288 void *zStart;
289 const GLuint count = span->end;
290 const GLuint *fragZ = span->array->z;
291 GLubyte *mask = span->array->mask;
292 void *zBufferVals;
293 GLuint *zBufferTemp = NULL;
294 GLuint passed;
295 GLuint zBits = _mesa_get_format_bits(rb->Format, GL_DEPTH_BITS);
296 GLboolean ztest16 = GL_FALSE;
297
298 if (span->arrayMask & SPAN_XY)
299 zStart = NULL;
300 else
301 zStart = _swrast_pixel_address(rb, span->x, span->y);
302
303 if (rb->Format == MESA_FORMAT_Z16 && !(span->arrayMask & SPAN_XY)) {
304 /* directly read/write row of 16-bit Z values */
305 zBufferVals = zStart;
306 ztest16 = GL_TRUE;
307 }
308 else if (rb->Format == MESA_FORMAT_Z32 && !(span->arrayMask & SPAN_XY)) {
309 /* directly read/write row of 32-bit Z values */
310 zBufferVals = zStart;
311 }
312 else {
313 /* copy Z buffer values into temp buffer (32-bit Z values) */
314 zBufferTemp = (GLuint *) malloc(count * sizeof(GLuint));
315 if (!zBufferTemp)
316 return 0;
317
318 if (span->arrayMask & SPAN_XY) {
319 get_z32_values(ctx, rb, count,
320 span->array->x, span->array->y, zBufferTemp);
321 }
322 else {
323 _mesa_unpack_uint_z_row(rb->Format, count, zStart, zBufferTemp);
324 }
325
326 if (zBits == 24) {
327 GLuint i;
328 /* Convert depth buffer values from 32 to 24 bits to match the
329 * fragment Z values generated by rasterization.
330 */
331 for (i = 0; i < count; i++) {
332 zBufferTemp[i] >>= 8;
333 }
334 }
335 else if (zBits == 16) {
336 GLuint i;
337 /* Convert depth buffer values from 32 to 16 bits */
338 for (i = 0; i < count; i++) {
339 zBufferTemp[i] >>= 16;
340 }
341 }
342 else {
343 assert(zBits == 32);
344 }
345
346 zBufferVals = zBufferTemp;
347 }
348
349 /* do the depth test either with 16 or 32-bit values */
350 if (ztest16)
351 passed = depth_test_span16(ctx, count, zBufferVals, fragZ, mask);
352 else
353 passed = depth_test_span32(ctx, count, zBufferVals, fragZ, mask);
354
355 if (zBufferTemp) {
356 /* need to write temp Z values back into the buffer */
357
358 /* Convert depth buffer values back to 32-bit values. The least
359 * significant bits don't matter since they'll get dropped when
360 * they're packed back into the depth buffer.
361 */
362 if (zBits == 24) {
363 GLuint i;
364 for (i = 0; i < count; i++) {
365 zBufferTemp[i] = (zBufferTemp[i] << 8);
366 }
367 }
368 else if (zBits == 16) {
369 GLuint i;
370 for (i = 0; i < count; i++) {
371 zBufferTemp[i] = zBufferTemp[i] << 16;
372 }
373 }
374
375 if (span->arrayMask & SPAN_XY) {
376 /* random locations */
377 put_z32_values(ctx, rb, count, span->array->x, span->array->y,
378 zBufferTemp, mask);
379 }
380 else {
381 /* horizontal row */
382 gl_pack_uint_z_func packZ = _mesa_get_pack_uint_z_func(rb->Format);
383 GLubyte *dst = zStart;
384 GLuint i;
385 for (i = 0; i < count; i++) {
386 if (mask[i]) {
387 packZ(&zBufferTemp[i], dst);
388 }
389 dst += bpp;
390 }
391 }
392
393 free(zBufferTemp);
394 }
395
396 if (passed < count) {
397 span->writeAll = GL_FALSE;
398 }
399 return passed;
400 }
401
402
403 /**
404 * GL_EXT_depth_bounds_test extension.
405 * Discard fragments depending on whether the corresponding Z-buffer
406 * values are outside the depth bounds test range.
407 * Note: we test the Z buffer values, not the fragment Z values!
408 * \return GL_TRUE if any fragments pass, GL_FALSE if no fragments pass
409 */
410 GLboolean
411 _swrast_depth_bounds_test( struct gl_context *ctx, SWspan *span )
412 {
413 struct gl_framebuffer *fb = ctx->DrawBuffer;
414 struct gl_renderbuffer *rb = fb->Attachment[BUFFER_DEPTH].Renderbuffer;
415 GLubyte *zStart;
416 GLuint zMin = (GLuint) (ctx->Depth.BoundsMin * fb->_DepthMaxF + 0.5F);
417 GLuint zMax = (GLuint) (ctx->Depth.BoundsMax * fb->_DepthMaxF + 0.5F);
418 GLubyte *mask = span->array->mask;
419 const GLuint count = span->end;
420 GLuint i;
421 GLboolean anyPass = GL_FALSE;
422 GLuint *zBufferTemp;
423 const GLuint *zBufferVals;
424
425 zBufferTemp = (GLuint *) malloc(count * sizeof(GLuint));
426 if (!zBufferTemp) {
427 /* don't generate a stream of OUT_OF_MEMORY errors here */
428 return GL_FALSE;
429 }
430
431 if (span->arrayMask & SPAN_XY)
432 zStart = NULL;
433 else
434 zStart = _swrast_pixel_address(rb, span->x, span->y);
435
436 if (rb->Format == MESA_FORMAT_Z32 && !(span->arrayMask & SPAN_XY)) {
437 /* directly access 32-bit values in the depth buffer */
438 zBufferVals = (const GLuint *) zStart;
439 }
440 else {
441 /* unpack Z values into a temporary array */
442 if (span->arrayMask & SPAN_XY) {
443 get_z32_values(ctx, rb, count, span->array->x, span->array->y,
444 zBufferTemp);
445 }
446 else {
447 _mesa_unpack_uint_z_row(rb->Format, count, zStart, zBufferTemp);
448 }
449 zBufferVals = zBufferTemp;
450 }
451
452 /* Now do the tests */
453 for (i = 0; i < count; i++) {
454 if (mask[i]) {
455 if (zBufferVals[i] < zMin || zBufferVals[i] > zMax)
456 mask[i] = GL_FALSE;
457 else
458 anyPass = GL_TRUE;
459 }
460 }
461
462 free(zBufferTemp);
463
464 return anyPass;
465 }
466
467
468
469 /**********************************************************************/
470 /***** Read Depth Buffer *****/
471 /**********************************************************************/
472
473
474 /**
475 * Read a span of depth values from the given depth renderbuffer, returning
476 * the values as GLfloats.
477 * This function does clipping to prevent reading outside the depth buffer's
478 * bounds.
479 */
480 void
481 _swrast_read_depth_span_float(struct gl_context *ctx,
482 struct gl_renderbuffer *rb,
483 GLint n, GLint x, GLint y, GLfloat depth[])
484 {
485 if (!rb) {
486 /* really only doing this to prevent FP exceptions later */
487 memset(depth, 0, n * sizeof(GLfloat));
488 return;
489 }
490
491 if (y < 0 || y >= (GLint) rb->Height ||
492 x + n <= 0 || x >= (GLint) rb->Width) {
493 /* span is completely outside framebuffer */
494 memset(depth, 0, n * sizeof(GLfloat));
495 return;
496 }
497
498 if (x < 0) {
499 GLint dx = -x;
500 GLint i;
501 for (i = 0; i < dx; i++)
502 depth[i] = 0.0;
503 x = 0;
504 n -= dx;
505 depth += dx;
506 }
507 if (x + n > (GLint) rb->Width) {
508 GLint dx = x + n - (GLint) rb->Width;
509 GLint i;
510 for (i = 0; i < dx; i++)
511 depth[n - i - 1] = 0.0;
512 n -= dx;
513 }
514 if (n <= 0) {
515 return;
516 }
517
518 _mesa_unpack_float_z_row(rb->Format, n, _swrast_pixel_address(rb, x, y),
519 depth);
520 }
521
522
523 /**
524 * Clear the given z/depth renderbuffer. If the buffer is a combined
525 * depth+stencil buffer, only the Z bits will be touched.
526 */
527 void
528 _swrast_clear_depth_buffer(struct gl_context *ctx)
529 {
530 struct gl_renderbuffer *rb =
531 ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
532 GLint x, y, width, height;
533 GLubyte *map;
534 GLint rowStride, i, j;
535 GLbitfield mapMode;
536
537 if (!rb || !ctx->Depth.Mask) {
538 /* no depth buffer, or writing to it is disabled */
539 return;
540 }
541
542 /* compute region to clear */
543 x = ctx->DrawBuffer->_Xmin;
544 y = ctx->DrawBuffer->_Ymin;
545 width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
546 height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
547
548 mapMode = GL_MAP_WRITE_BIT;
549 if (rb->Format == MESA_FORMAT_S8_Z24 ||
550 rb->Format == MESA_FORMAT_X8_Z24 ||
551 rb->Format == MESA_FORMAT_Z24_S8 ||
552 rb->Format == MESA_FORMAT_Z24_X8) {
553 mapMode |= GL_MAP_READ_BIT;
554 }
555
556 ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height,
557 mapMode, &map, &rowStride);
558 if (!map) {
559 _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear(depth)");
560 return;
561 }
562
563 switch (rb->Format) {
564 case MESA_FORMAT_Z16:
565 {
566 GLfloat clear = (GLfloat) ctx->Depth.Clear;
567 GLushort clearVal = 0;
568 _mesa_pack_float_z_row(rb->Format, 1, &clear, &clearVal);
569 if (clearVal == 0xffff && width * 2 == rowStride) {
570 /* common case */
571 memset(map, 0xff, width * height * 2);
572 }
573 else {
574 for (i = 0; i < height; i++) {
575 GLushort *row = (GLushort *) map;
576 for (j = 0; j < width; j++) {
577 row[j] = clearVal;
578 }
579 map += rowStride;
580 }
581 }
582 }
583 break;
584 case MESA_FORMAT_Z32:
585 case MESA_FORMAT_Z32_FLOAT:
586 {
587 GLfloat clear = (GLfloat) ctx->Depth.Clear;
588 GLuint clearVal = 0;
589 _mesa_pack_float_z_row(rb->Format, 1, &clear, &clearVal);
590 for (i = 0; i < height; i++) {
591 GLuint *row = (GLuint *) map;
592 for (j = 0; j < width; j++) {
593 row[j] = clearVal;
594 }
595 map += rowStride;
596 }
597 }
598 break;
599 case MESA_FORMAT_S8_Z24:
600 case MESA_FORMAT_X8_Z24:
601 case MESA_FORMAT_Z24_S8:
602 case MESA_FORMAT_Z24_X8:
603 {
604 GLfloat clear = (GLfloat) ctx->Depth.Clear;
605 GLuint clearVal = 0;
606 GLuint mask;
607
608 if (rb->Format == MESA_FORMAT_S8_Z24 ||
609 rb->Format == MESA_FORMAT_X8_Z24)
610 mask = 0xff000000;
611 else
612 mask = 0xff;
613
614 _mesa_pack_float_z_row(rb->Format, 1, &clear, &clearVal);
615 for (i = 0; i < height; i++) {
616 GLuint *row = (GLuint *) map;
617 for (j = 0; j < width; j++) {
618 row[j] = (row[j] & mask) | clearVal;
619 }
620 map += rowStride;
621 }
622
623 }
624 break;
625 case MESA_FORMAT_Z32_FLOAT_X24S8:
626 /* XXX untested */
627 {
628 GLfloat clearVal = (GLfloat) ctx->Depth.Clear;
629 for (i = 0; i < height; i++) {
630 GLfloat *row = (GLfloat *) map;
631 for (j = 0; j < width; j++) {
632 row[j * 2] = clearVal;
633 }
634 map += rowStride;
635 }
636 }
637 break;
638 default:
639 _mesa_problem(ctx, "Unexpected depth buffer format %s"
640 " in _swrast_clear_depth_buffer()",
641 _mesa_get_format_name(rb->Format));
642 }
643
644 ctx->Driver.UnmapRenderbuffer(ctx, rb);
645 }
646
647
648
649
650 /**
651 * Clear both depth and stencil values in a combined depth+stencil buffer.
652 */
653 void
654 _swrast_clear_depth_stencil_buffer(struct gl_context *ctx)
655 {
656 const GLubyte stencilBits = ctx->DrawBuffer->Visual.stencilBits;
657 const GLuint writeMask = ctx->Stencil.WriteMask[0];
658 const GLuint stencilMax = (1 << stencilBits) - 1;
659 struct gl_renderbuffer *rb =
660 ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
661 GLint x, y, width, height;
662 GLbitfield mapMode;
663 GLubyte *map;
664 GLint rowStride, i, j;
665
666 /* check that we really have a combined depth+stencil buffer */
667 assert(rb == ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer);
668
669 /* compute region to clear */
670 x = ctx->DrawBuffer->_Xmin;
671 y = ctx->DrawBuffer->_Ymin;
672 width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
673 height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
674
675 mapMode = GL_MAP_WRITE_BIT;
676 if ((writeMask & stencilMax) != stencilMax) {
677 /* need to mask stencil values */
678 mapMode |= GL_MAP_READ_BIT;
679 }
680
681 ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height,
682 mapMode, &map, &rowStride);
683 if (!map) {
684 _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear(depth+stencil)");
685 return;
686 }
687
688 switch (rb->Format) {
689 case MESA_FORMAT_S8_Z24:
690 case MESA_FORMAT_Z24_S8:
691 {
692 GLfloat zClear = (GLfloat) ctx->Depth.Clear;
693 GLuint clear = 0, mask;
694
695 _mesa_pack_float_z_row(rb->Format, 1, &zClear, &clear);
696
697 if (rb->Format == MESA_FORMAT_S8_Z24) {
698 mask = ((~writeMask) & 0xff) << 24;
699 clear |= (ctx->Stencil.Clear & writeMask & 0xff) << 24;
700 }
701 else {
702 mask = ((~writeMask) & 0xff);
703 clear |= (ctx->Stencil.Clear & writeMask & 0xff);
704 }
705
706 for (i = 0; i < height; i++) {
707 GLuint *row = (GLuint *) map;
708 if (mask != 0x0) {
709 for (j = 0; j < width; j++) {
710 row[j] = (row[j] & mask) | clear;
711 }
712 }
713 else {
714 for (j = 0; j < width; j++) {
715 row[j] = clear;
716 }
717 }
718 map += rowStride;
719 }
720 }
721 break;
722 case MESA_FORMAT_Z32_FLOAT_X24S8:
723 /* XXX untested */
724 {
725 const GLfloat zClear = (GLfloat) ctx->Depth.Clear;
726 const GLuint sClear = ctx->Stencil.Clear & writeMask;
727 const GLuint sMask = (~writeMask) & 0xff;
728 for (i = 0; i < height; i++) {
729 GLfloat *zRow = (GLfloat *) map;
730 GLuint *sRow = (GLuint *) map;
731 for (j = 0; j < width; j++) {
732 zRow[j * 2 + 0] = zClear;
733 }
734 if (sMask != 0) {
735 for (j = 0; j < width; j++) {
736 sRow[j * 2 + 1] = (sRow[j * 2 + 1] & sMask) | sClear;
737 }
738 }
739 else {
740 for (j = 0; j < width; j++) {
741 sRow[j * 2 + 1] = sClear;
742 }
743 }
744 map += rowStride;
745 }
746 }
747 break;
748 default:
749 _mesa_problem(ctx, "Unexpected depth buffer format %s"
750 " in _swrast_clear_depth_buffer()",
751 _mesa_get_format_name(rb->Format));
752 }
753
754 ctx->Driver.UnmapRenderbuffer(ctx, rb);
755
756 }