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swrast: new assertions in _swrast_pixel_address()
[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 const GLint w = rb->Width, h = rb->Height;
216 const GLubyte *map = _swrast_pixel_address(rb, 0, 0);
217 GLuint i;
218
219 if (rb->Format == MESA_FORMAT_Z32) {
220 const GLint rowStride = rb->RowStride * 4;
221 for (i = 0; i < count; i++) {
222 if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
223 zbuffer[i] = *((GLuint *) (map + y[i] * rowStride + x[i] * 4));
224 }
225 }
226 }
227 else {
228 const GLint bpp = _mesa_get_format_bytes(rb->Format);
229 const GLint rowStride = rb->RowStride * bpp;
230 for (i = 0; i < count; i++) {
231 if (x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
232 const GLubyte *src = map + y[i] * rowStride+ x[i] * bpp;
233 _mesa_unpack_uint_z_row(rb->Format, 1, src, &zbuffer[i]);
234 }
235 }
236 }
237 }
238
239
240 /**
241 * Put an array of 32-bit z values into the depth buffer.
242 * Note: the z values are always in the range [0, 2^32-1].
243 */
244 static void
245 put_z32_values(struct gl_context *ctx, struct gl_renderbuffer *rb,
246 GLuint count, const GLint x[], const GLint y[],
247 const GLuint zvalues[], const GLubyte mask[])
248 {
249 const GLint w = rb->Width, h = rb->Height;
250 GLubyte *map = _swrast_pixel_address(rb, 0, 0);
251 GLuint i;
252
253 if (rb->Format == MESA_FORMAT_Z32) {
254 const GLuint rowStride = rb->RowStride * 4;
255 for (i = 0; i < count; i++) {
256 if (mask[i] && x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
257 GLuint *dst = (GLuint *) (map + y[i] * rowStride + x[i] * 4);
258 *dst = zvalues[i];
259 }
260 }
261 }
262 else {
263 gl_pack_uint_z_func packZ = _mesa_get_pack_uint_z_func(rb->Format);
264 const GLint bpp = _mesa_get_format_bytes(rb->Format);
265 const GLint rowStride = rb->RowStride * bpp;
266 for (i = 0; i < count; i++) {
267 if (mask[i] && x[i] >= 0 && y[i] >= 0 && x[i] < w && y[i] < h) {
268 void *dst = map + y[i] * rowStride + x[i] * bpp;
269 packZ(zvalues + i, dst);
270 }
271 }
272 }
273 }
274
275
276 /**
277 * Apply depth (Z) buffer testing to the span.
278 * \return approx number of pixels that passed (only zero is reliable)
279 */
280 GLuint
281 _swrast_depth_test_span(struct gl_context *ctx, SWspan *span)
282 {
283 struct gl_framebuffer *fb = ctx->DrawBuffer;
284 struct gl_renderbuffer *rb = fb->Attachment[BUFFER_DEPTH].Renderbuffer;
285 const GLint bpp = _mesa_get_format_bytes(rb->Format);
286 void *zStart;
287 const GLuint count = span->end;
288 const GLuint *fragZ = span->array->z;
289 GLubyte *mask = span->array->mask;
290 void *zBufferVals;
291 GLuint *zBufferTemp = NULL;
292 GLuint passed;
293 GLuint zBits = _mesa_get_format_bits(rb->Format, GL_DEPTH_BITS);
294 GLboolean ztest16 = GL_FALSE;
295
296 if (span->arrayMask & SPAN_XY)
297 zStart = NULL;
298 else
299 zStart = _swrast_pixel_address(rb, span->x, span->y);
300
301 if (rb->Format == MESA_FORMAT_Z16 && !(span->arrayMask & SPAN_XY)) {
302 /* directly read/write row of 16-bit Z values */
303 zBufferVals = zStart;
304 ztest16 = GL_TRUE;
305 }
306 else if (rb->Format == MESA_FORMAT_Z32 && !(span->arrayMask & SPAN_XY)) {
307 /* directly read/write row of 32-bit Z values */
308 zBufferVals = zStart;
309 }
310 else {
311 /* copy Z buffer values into temp buffer (32-bit Z values) */
312 zBufferTemp = (GLuint *) malloc(count * sizeof(GLuint));
313 if (!zBufferTemp)
314 return 0;
315
316 if (span->arrayMask & SPAN_XY) {
317 get_z32_values(ctx, rb, count,
318 span->array->x, span->array->y, zBufferTemp);
319 }
320 else {
321 _mesa_unpack_uint_z_row(rb->Format, count, zStart, zBufferTemp);
322 }
323
324 if (zBits == 24) {
325 GLuint i;
326 /* Convert depth buffer values from 32 to 24 bits to match the
327 * fragment Z values generated by rasterization.
328 */
329 for (i = 0; i < count; i++) {
330 zBufferTemp[i] >>= 8;
331 }
332 }
333 else if (zBits == 16) {
334 GLuint i;
335 /* Convert depth buffer values from 32 to 16 bits */
336 for (i = 0; i < count; i++) {
337 zBufferTemp[i] >>= 16;
338 }
339 }
340 else {
341 assert(zBits == 32);
342 }
343
344 zBufferVals = zBufferTemp;
345 }
346
347 /* do the depth test either with 16 or 32-bit values */
348 if (ztest16)
349 passed = depth_test_span16(ctx, count, zBufferVals, fragZ, mask);
350 else
351 passed = depth_test_span32(ctx, count, zBufferVals, fragZ, mask);
352
353 if (zBufferTemp) {
354 /* need to write temp Z values back into the buffer */
355
356 /* Convert depth buffer values back to 32-bit values. The least
357 * significant bits don't matter since they'll get dropped when
358 * they're packed back into the depth buffer.
359 */
360 if (zBits == 24) {
361 GLuint i;
362 for (i = 0; i < count; i++) {
363 zBufferTemp[i] = (zBufferTemp[i] << 8);
364 }
365 }
366 else if (zBits == 16) {
367 GLuint i;
368 for (i = 0; i < count; i++) {
369 zBufferTemp[i] = zBufferTemp[i] << 16;
370 }
371 }
372
373 if (span->arrayMask & SPAN_XY) {
374 /* random locations */
375 put_z32_values(ctx, rb, count, span->array->x, span->array->y,
376 zBufferTemp, mask);
377 }
378 else {
379 /* horizontal row */
380 gl_pack_uint_z_func packZ = _mesa_get_pack_uint_z_func(rb->Format);
381 GLubyte *dst = zStart;
382 GLuint i;
383 for (i = 0; i < count; i++) {
384 if (mask[i]) {
385 packZ(&zBufferTemp[i], dst);
386 }
387 dst += bpp;
388 }
389 }
390
391 free(zBufferTemp);
392 }
393
394 if (passed < count) {
395 span->writeAll = GL_FALSE;
396 }
397 return passed;
398 }
399
400
401 /**
402 * GL_EXT_depth_bounds_test extension.
403 * Discard fragments depending on whether the corresponding Z-buffer
404 * values are outside the depth bounds test range.
405 * Note: we test the Z buffer values, not the fragment Z values!
406 * \return GL_TRUE if any fragments pass, GL_FALSE if no fragments pass
407 */
408 GLboolean
409 _swrast_depth_bounds_test( struct gl_context *ctx, SWspan *span )
410 {
411 struct gl_framebuffer *fb = ctx->DrawBuffer;
412 struct gl_renderbuffer *rb = fb->Attachment[BUFFER_DEPTH].Renderbuffer;
413 GLubyte *zStart;
414 GLuint zMin = (GLuint) (ctx->Depth.BoundsMin * fb->_DepthMaxF + 0.5F);
415 GLuint zMax = (GLuint) (ctx->Depth.BoundsMax * fb->_DepthMaxF + 0.5F);
416 GLubyte *mask = span->array->mask;
417 const GLuint count = span->end;
418 GLuint i;
419 GLboolean anyPass = GL_FALSE;
420 GLuint zBufferTemp[MAX_WIDTH];
421 const GLuint *zBufferVals;
422
423 if (span->arrayMask & SPAN_XY)
424 zStart = NULL;
425 else
426 zStart = _swrast_pixel_address(rb, span->x, span->y);
427
428 if (rb->Format == MESA_FORMAT_Z32 && !(span->arrayMask & SPAN_XY)) {
429 /* directly access 32-bit values in the depth buffer */
430 zBufferVals = (const GLuint *) zStart;
431 }
432 else {
433 /* unpack Z values into a temporary array */
434 if (span->arrayMask & SPAN_XY) {
435 get_z32_values(ctx, rb, count, span->array->x, span->array->y,
436 zBufferTemp);
437 }
438 else {
439 _mesa_unpack_uint_z_row(rb->Format, count, zStart, zBufferTemp);
440 }
441 zBufferVals = zBufferTemp;
442 }
443
444 /* Now do the tests */
445 for (i = 0; i < count; i++) {
446 if (mask[i]) {
447 if (zBufferVals[i] < zMin || zBufferVals[i] > zMax)
448 mask[i] = GL_FALSE;
449 else
450 anyPass = GL_TRUE;
451 }
452 }
453
454 return anyPass;
455 }
456
457
458
459 /**********************************************************************/
460 /***** Read Depth Buffer *****/
461 /**********************************************************************/
462
463
464 /**
465 * Read a span of depth values from the given depth renderbuffer, returning
466 * the values as GLfloats.
467 * This function does clipping to prevent reading outside the depth buffer's
468 * bounds.
469 */
470 void
471 _swrast_read_depth_span_float(struct gl_context *ctx,
472 struct gl_renderbuffer *rb,
473 GLint n, GLint x, GLint y, GLfloat depth[])
474 {
475 if (!rb) {
476 /* really only doing this to prevent FP exceptions later */
477 memset(depth, 0, n * sizeof(GLfloat));
478 return;
479 }
480
481 if (y < 0 || y >= (GLint) rb->Height ||
482 x + n <= 0 || x >= (GLint) rb->Width) {
483 /* span is completely outside framebuffer */
484 memset(depth, 0, n * sizeof(GLfloat));
485 return;
486 }
487
488 if (x < 0) {
489 GLint dx = -x;
490 GLint i;
491 for (i = 0; i < dx; i++)
492 depth[i] = 0.0;
493 x = 0;
494 n -= dx;
495 depth += dx;
496 }
497 if (x + n > (GLint) rb->Width) {
498 GLint dx = x + n - (GLint) rb->Width;
499 GLint i;
500 for (i = 0; i < dx; i++)
501 depth[n - i - 1] = 0.0;
502 n -= dx;
503 }
504 if (n <= 0) {
505 return;
506 }
507
508 _mesa_unpack_float_z_row(rb->Format, n, _swrast_pixel_address(rb, x, y),
509 depth);
510 }
511
512
513 /**
514 * Clear the given z/depth renderbuffer. If the buffer is a combined
515 * depth+stencil buffer, only the Z bits will be touched.
516 */
517 void
518 _swrast_clear_depth_buffer(struct gl_context *ctx)
519 {
520 struct gl_renderbuffer *rb =
521 ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
522 GLint x, y, width, height;
523 GLubyte *map;
524 GLint rowStride, i, j;
525 GLbitfield mapMode;
526
527 if (!rb || !ctx->Depth.Mask) {
528 /* no depth buffer, or writing to it is disabled */
529 return;
530 }
531
532 /* compute region to clear */
533 x = ctx->DrawBuffer->_Xmin;
534 y = ctx->DrawBuffer->_Ymin;
535 width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
536 height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
537
538 mapMode = GL_MAP_WRITE_BIT;
539 if (rb->Format == MESA_FORMAT_S8_Z24 ||
540 rb->Format == MESA_FORMAT_X8_Z24 ||
541 rb->Format == MESA_FORMAT_Z24_S8 ||
542 rb->Format == MESA_FORMAT_Z24_X8) {
543 mapMode |= GL_MAP_READ_BIT;
544 }
545
546 ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height,
547 mapMode, &map, &rowStride);
548 if (!map) {
549 _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear(depth)");
550 return;
551 }
552
553 switch (rb->Format) {
554 case MESA_FORMAT_Z16:
555 {
556 GLfloat clear = (GLfloat) ctx->Depth.Clear;
557 GLushort clearVal = 0;
558 _mesa_pack_float_z_row(rb->Format, 1, &clear, &clearVal);
559 if (clearVal == 0xffff && width * 2 == rowStride) {
560 /* common case */
561 memset(map, 0xff, width * height * 2);
562 }
563 else {
564 for (i = 0; i < height; i++) {
565 GLushort *row = (GLushort *) map;
566 for (j = 0; j < width; j++) {
567 row[j] = clearVal;
568 }
569 map += rowStride;
570 }
571 }
572 }
573 break;
574 case MESA_FORMAT_Z32:
575 case MESA_FORMAT_Z32_FLOAT:
576 {
577 GLfloat clear = (GLfloat) ctx->Depth.Clear;
578 GLuint clearVal = 0;
579 _mesa_pack_float_z_row(rb->Format, 1, &clear, &clearVal);
580 for (i = 0; i < height; i++) {
581 GLuint *row = (GLuint *) map;
582 for (j = 0; j < width; j++) {
583 row[j] = clearVal;
584 }
585 map += rowStride;
586 }
587 }
588 break;
589 case MESA_FORMAT_S8_Z24:
590 case MESA_FORMAT_X8_Z24:
591 case MESA_FORMAT_Z24_S8:
592 case MESA_FORMAT_Z24_X8:
593 {
594 GLfloat clear = (GLfloat) ctx->Depth.Clear;
595 GLuint clearVal = 0;
596 GLuint mask;
597
598 if (rb->Format == MESA_FORMAT_S8_Z24 ||
599 rb->Format == MESA_FORMAT_X8_Z24)
600 mask = 0xff000000;
601 else
602 mask = 0xff;
603
604 _mesa_pack_float_z_row(rb->Format, 1, &clear, &clearVal);
605 for (i = 0; i < height; i++) {
606 GLuint *row = (GLuint *) map;
607 for (j = 0; j < width; j++) {
608 row[j] = (row[j] & mask) | clearVal;
609 }
610 map += rowStride;
611 }
612
613 }
614 break;
615 case MESA_FORMAT_Z32_FLOAT_X24S8:
616 /* XXX untested */
617 {
618 GLfloat clearVal = (GLfloat) ctx->Depth.Clear;
619 for (i = 0; i < height; i++) {
620 GLfloat *row = (GLfloat *) map;
621 for (j = 0; j < width; j++) {
622 row[j * 2] = clearVal;
623 }
624 map += rowStride;
625 }
626 }
627 break;
628 default:
629 _mesa_problem(ctx, "Unexpected depth buffer format %s"
630 " in _swrast_clear_depth_buffer()",
631 _mesa_get_format_name(rb->Format));
632 }
633
634 ctx->Driver.UnmapRenderbuffer(ctx, rb);
635 }
636
637
638
639
640 /**
641 * Clear both depth and stencil values in a combined depth+stencil buffer.
642 */
643 void
644 _swrast_clear_depth_stencil_buffer(struct gl_context *ctx)
645 {
646 const GLubyte stencilBits = ctx->DrawBuffer->Visual.stencilBits;
647 const GLuint writeMask = ctx->Stencil.WriteMask[0];
648 const GLuint stencilMax = (1 << stencilBits) - 1;
649 struct gl_renderbuffer *rb =
650 ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
651 GLint x, y, width, height;
652 GLbitfield mapMode;
653 GLubyte *map;
654 GLint rowStride, i, j;
655
656 /* check that we really have a combined depth+stencil buffer */
657 assert(rb == ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer);
658
659 /* compute region to clear */
660 x = ctx->DrawBuffer->_Xmin;
661 y = ctx->DrawBuffer->_Ymin;
662 width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
663 height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
664
665 mapMode = GL_MAP_WRITE_BIT;
666 if ((writeMask & stencilMax) != stencilMax) {
667 /* need to mask stencil values */
668 mapMode |= GL_MAP_READ_BIT;
669 }
670
671 ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height,
672 mapMode, &map, &rowStride);
673 if (!map) {
674 _mesa_error(ctx, GL_OUT_OF_MEMORY, "glClear(depth+stencil)");
675 return;
676 }
677
678 switch (rb->Format) {
679 case MESA_FORMAT_S8_Z24:
680 case MESA_FORMAT_Z24_S8:
681 {
682 GLfloat zClear = (GLfloat) ctx->Depth.Clear;
683 GLuint clear = 0, mask;
684
685 _mesa_pack_float_z_row(rb->Format, 1, &zClear, &clear);
686
687 if (rb->Format == MESA_FORMAT_S8_Z24) {
688 mask = ((~writeMask) & 0xff) << 24;
689 clear |= (ctx->Stencil.Clear & writeMask & 0xff) << 24;
690 }
691 else {
692 mask = ((~writeMask) & 0xff);
693 clear |= (ctx->Stencil.Clear & writeMask & 0xff);
694 }
695
696 for (i = 0; i < height; i++) {
697 GLuint *row = (GLuint *) map;
698 if (mask != 0x0) {
699 for (j = 0; j < width; j++) {
700 row[j] = (row[j] & mask) | clear;
701 }
702 }
703 else {
704 for (j = 0; j < width; j++) {
705 row[j] = clear;
706 }
707 }
708 map += rowStride;
709 }
710 }
711 break;
712 case MESA_FORMAT_Z32_FLOAT_X24S8:
713 /* XXX untested */
714 {
715 const GLfloat zClear = (GLfloat) ctx->Depth.Clear;
716 const GLuint sClear = ctx->Stencil.Clear & writeMask;
717 const GLuint sMask = (~writeMask) & 0xff;
718 for (i = 0; i < height; i++) {
719 GLfloat *zRow = (GLfloat *) map;
720 GLuint *sRow = (GLuint *) map;
721 for (j = 0; j < width; j++) {
722 zRow[j * 2 + 0] = zClear;
723 }
724 if (sMask != 0) {
725 for (j = 0; j < width; j++) {
726 sRow[j * 2 + 1] = (sRow[j * 2 + 1] & sMask) | sClear;
727 }
728 }
729 else {
730 for (j = 0; j < width; j++) {
731 sRow[j * 2 + 1] = sClear;
732 }
733 }
734 map += rowStride;
735 }
736 }
737 break;
738 default:
739 _mesa_problem(ctx, "Unexpected depth buffer format %s"
740 " in _swrast_clear_depth_buffer()",
741 _mesa_get_format_name(rb->Format));
742 }
743
744 ctx->Driver.UnmapRenderbuffer(ctx, rb);
745
746 }