Details | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
57 | pj | 1 | /* $Id: s_stencil.c,v 1.1 2003-02-28 11:49:43 pj Exp $ */ |
2 | |||
3 | /* |
||
4 | * Mesa 3-D graphics library |
||
5 | * Version: 4.1 |
||
6 | * |
||
7 | * Copyright (C) 1999-2002 Brian Paul All Rights Reserved. |
||
8 | * |
||
9 | * Permission is hereby granted, free of charge, to any person obtaining a |
||
10 | * copy of this software and associated documentation files (the "Software"), |
||
11 | * to deal in the Software without restriction, including without limitation |
||
12 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
||
13 | * and/or sell copies of the Software, and to permit persons to whom the |
||
14 | * Software is furnished to do so, subject to the following conditions: |
||
15 | * |
||
16 | * The above copyright notice and this permission notice shall be included |
||
17 | * in all copies or substantial portions of the Software. |
||
18 | * |
||
19 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
||
20 | * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
||
21 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
||
22 | * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN |
||
23 | * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
||
24 | * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
||
25 | */ |
||
26 | |||
27 | |||
28 | #include "glheader.h" |
||
29 | #include "context.h" |
||
30 | #include "macros.h" |
||
31 | #include "imports.h" |
||
32 | |||
33 | #include "s_context.h" |
||
34 | #include "s_depth.h" |
||
35 | #include "s_stencil.h" |
||
36 | |||
37 | |||
38 | |||
39 | /* Stencil Logic: |
||
40 | |||
41 | IF stencil test fails THEN |
||
42 | Apply fail-op to stencil value |
||
43 | Don't write the pixel (RGBA,Z) |
||
44 | ELSE |
||
45 | IF doing depth test && depth test fails THEN |
||
46 | Apply zfail-op to stencil value |
||
47 | Write RGBA and Z to appropriate buffers |
||
48 | ELSE |
||
49 | Apply zpass-op to stencil value |
||
50 | ENDIF |
||
51 | |||
52 | */ |
||
53 | |||
54 | |||
55 | /* |
||
56 | * Return the address of a stencil buffer value given the window coords: |
||
57 | */ |
||
58 | #define STENCIL_ADDRESS(X,Y) \ |
||
59 | (ctx->DrawBuffer->Stencil + ctx->DrawBuffer->Width * (Y) + (X)) |
||
60 | |||
61 | |||
62 | |||
63 | /** |
||
64 | * Apply the given stencil operator to the array of stencil values. |
||
65 | * Don't touch stencil[i] if mask[i] is zero. |
||
66 | * Input: n - size of stencil array |
||
67 | * oper - the stencil buffer operator |
||
68 | * face - 0 or 1 for front or back face operation |
||
69 | * stencil - array of stencil values |
||
70 | * mask - array [n] of flag: 1=apply operator, 0=don't apply operator |
||
71 | * Output: stencil - modified values |
||
72 | */ |
||
73 | static void |
||
74 | apply_stencil_op( const GLcontext *ctx, GLenum oper, GLuint face, |
||
75 | GLuint n, GLstencil stencil[], const GLubyte mask[] ) |
||
76 | { |
||
77 | const GLstencil ref = ctx->Stencil.Ref[face]; |
||
78 | const GLstencil wrtmask = ctx->Stencil.WriteMask[face]; |
||
79 | const GLstencil invmask = (GLstencil) (~wrtmask); |
||
80 | GLuint i; |
||
81 | |||
82 | switch (oper) { |
||
83 | case GL_KEEP: |
||
84 | /* do nothing */ |
||
85 | break; |
||
86 | case GL_ZERO: |
||
87 | if (invmask==0) { |
||
88 | for (i=0;i<n;i++) { |
||
89 | if (mask[i]) { |
||
90 | stencil[i] = 0; |
||
91 | } |
||
92 | } |
||
93 | } |
||
94 | else { |
||
95 | for (i=0;i<n;i++) { |
||
96 | if (mask[i]) { |
||
97 | stencil[i] = (GLstencil) (stencil[i] & invmask); |
||
98 | } |
||
99 | } |
||
100 | } |
||
101 | break; |
||
102 | case GL_REPLACE: |
||
103 | if (invmask==0) { |
||
104 | for (i=0;i<n;i++) { |
||
105 | if (mask[i]) { |
||
106 | stencil[i] = ref; |
||
107 | } |
||
108 | } |
||
109 | } |
||
110 | else { |
||
111 | for (i=0;i<n;i++) { |
||
112 | if (mask[i]) { |
||
113 | GLstencil s = stencil[i]; |
||
114 | stencil[i] = (GLstencil) ((invmask & s ) | (wrtmask & ref)); |
||
115 | } |
||
116 | } |
||
117 | } |
||
118 | break; |
||
119 | case GL_INCR: |
||
120 | if (invmask==0) { |
||
121 | for (i=0;i<n;i++) { |
||
122 | if (mask[i]) { |
||
123 | GLstencil s = stencil[i]; |
||
124 | if (s < STENCIL_MAX) { |
||
125 | stencil[i] = (GLstencil) (s+1); |
||
126 | } |
||
127 | } |
||
128 | } |
||
129 | } |
||
130 | else { |
||
131 | for (i=0;i<n;i++) { |
||
132 | if (mask[i]) { |
||
133 | /* VERIFY logic of adding 1 to a write-masked value */ |
||
134 | GLstencil s = stencil[i]; |
||
135 | if (s < STENCIL_MAX) { |
||
136 | stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s+1))); |
||
137 | } |
||
138 | } |
||
139 | } |
||
140 | } |
||
141 | break; |
||
142 | case GL_DECR: |
||
143 | if (invmask==0) { |
||
144 | for (i=0;i<n;i++) { |
||
145 | if (mask[i]) { |
||
146 | GLstencil s = stencil[i]; |
||
147 | if (s>0) { |
||
148 | stencil[i] = (GLstencil) (s-1); |
||
149 | } |
||
150 | } |
||
151 | } |
||
152 | } |
||
153 | else { |
||
154 | for (i=0;i<n;i++) { |
||
155 | if (mask[i]) { |
||
156 | /* VERIFY logic of subtracting 1 to a write-masked value */ |
||
157 | GLstencil s = stencil[i]; |
||
158 | if (s>0) { |
||
159 | stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s-1))); |
||
160 | } |
||
161 | } |
||
162 | } |
||
163 | } |
||
164 | break; |
||
165 | case GL_INCR_WRAP_EXT: |
||
166 | if (invmask==0) { |
||
167 | for (i=0;i<n;i++) { |
||
168 | if (mask[i]) { |
||
169 | stencil[i]++; |
||
170 | } |
||
171 | } |
||
172 | } |
||
173 | else { |
||
174 | for (i=0;i<n;i++) { |
||
175 | if (mask[i]) { |
||
176 | GLstencil s = stencil[i]; |
||
177 | stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s+1))); |
||
178 | } |
||
179 | } |
||
180 | } |
||
181 | break; |
||
182 | case GL_DECR_WRAP_EXT: |
||
183 | if (invmask==0) { |
||
184 | for (i=0;i<n;i++) { |
||
185 | if (mask[i]) { |
||
186 | stencil[i]--; |
||
187 | } |
||
188 | } |
||
189 | } |
||
190 | else { |
||
191 | for (i=0;i<n;i++) { |
||
192 | if (mask[i]) { |
||
193 | GLstencil s = stencil[i]; |
||
194 | stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s-1))); |
||
195 | } |
||
196 | } |
||
197 | } |
||
198 | break; |
||
199 | case GL_INVERT: |
||
200 | if (invmask==0) { |
||
201 | for (i=0;i<n;i++) { |
||
202 | if (mask[i]) { |
||
203 | GLstencil s = stencil[i]; |
||
204 | stencil[i] = (GLstencil) ~s; |
||
205 | } |
||
206 | } |
||
207 | } |
||
208 | else { |
||
209 | for (i=0;i<n;i++) { |
||
210 | if (mask[i]) { |
||
211 | GLstencil s = stencil[i]; |
||
212 | stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & ~s)); |
||
213 | } |
||
214 | } |
||
215 | } |
||
216 | break; |
||
217 | default: |
||
218 | _mesa_problem(ctx, "Bad stencil op in apply_stencil_op"); |
||
219 | } |
||
220 | } |
||
221 | |||
222 | |||
223 | |||
224 | |||
225 | /** |
||
226 | * Apply stencil test to an array of stencil values (before depth buffering). |
||
227 | * Input: face - 0 or 1 for front or back-face polygons |
||
228 | * n - number of pixels in the array |
||
229 | * stencil - array of [n] stencil values |
||
230 | * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel |
||
231 | * Output: mask - pixels which fail the stencil test will have their |
||
232 | * mask flag set to 0. |
||
233 | * stencil - updated stencil values (where the test passed) |
||
234 | * Return: GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed. |
||
235 | */ |
||
236 | static GLboolean |
||
237 | do_stencil_test( GLcontext *ctx, GLuint face, GLuint n, GLstencil stencil[], |
||
238 | GLubyte mask[] ) |
||
239 | { |
||
240 | GLubyte fail[MAX_WIDTH]; |
||
241 | GLboolean allfail = GL_FALSE; |
||
242 | GLuint i; |
||
243 | GLstencil r, s; |
||
244 | const GLuint valueMask = ctx->Stencil.ValueMask[face]; |
||
245 | |||
246 | ASSERT(n <= MAX_WIDTH); |
||
247 | |||
248 | /* |
||
249 | * Perform stencil test. The results of this operation are stored |
||
250 | * in the fail[] array: |
||
251 | * IF fail[i] is non-zero THEN |
||
252 | * the stencil fail operator is to be applied |
||
253 | * ELSE |
||
254 | * the stencil fail operator is not to be applied |
||
255 | * ENDIF |
||
256 | */ |
||
257 | switch (ctx->Stencil.Function[face]) { |
||
258 | case GL_NEVER: |
||
259 | /* never pass; always fail */ |
||
260 | for (i=0;i<n;i++) { |
||
261 | if (mask[i]) { |
||
262 | mask[i] = 0; |
||
263 | fail[i] = 1; |
||
264 | } |
||
265 | else { |
||
266 | fail[i] = 0; |
||
267 | } |
||
268 | } |
||
269 | allfail = GL_TRUE; |
||
270 | break; |
||
271 | case GL_LESS: |
||
272 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
273 | for (i=0;i<n;i++) { |
||
274 | if (mask[i]) { |
||
275 | s = (GLstencil) (stencil[i] & valueMask); |
||
276 | if (r < s) { |
||
277 | /* passed */ |
||
278 | fail[i] = 0; |
||
279 | } |
||
280 | else { |
||
281 | fail[i] = 1; |
||
282 | mask[i] = 0; |
||
283 | } |
||
284 | } |
||
285 | else { |
||
286 | fail[i] = 0; |
||
287 | } |
||
288 | } |
||
289 | break; |
||
290 | case GL_LEQUAL: |
||
291 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
292 | for (i=0;i<n;i++) { |
||
293 | if (mask[i]) { |
||
294 | s = (GLstencil) (stencil[i] & valueMask); |
||
295 | if (r <= s) { |
||
296 | /* pass */ |
||
297 | fail[i] = 0; |
||
298 | } |
||
299 | else { |
||
300 | fail[i] = 1; |
||
301 | mask[i] = 0; |
||
302 | } |
||
303 | } |
||
304 | else { |
||
305 | fail[i] = 0; |
||
306 | } |
||
307 | } |
||
308 | break; |
||
309 | case GL_GREATER: |
||
310 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
311 | for (i=0;i<n;i++) { |
||
312 | if (mask[i]) { |
||
313 | s = (GLstencil) (stencil[i] & valueMask); |
||
314 | if (r > s) { |
||
315 | /* passed */ |
||
316 | fail[i] = 0; |
||
317 | } |
||
318 | else { |
||
319 | fail[i] = 1; |
||
320 | mask[i] = 0; |
||
321 | } |
||
322 | } |
||
323 | else { |
||
324 | fail[i] = 0; |
||
325 | } |
||
326 | } |
||
327 | break; |
||
328 | case GL_GEQUAL: |
||
329 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
330 | for (i=0;i<n;i++) { |
||
331 | if (mask[i]) { |
||
332 | s = (GLstencil) (stencil[i] & valueMask); |
||
333 | if (r >= s) { |
||
334 | /* passed */ |
||
335 | fail[i] = 0; |
||
336 | } |
||
337 | else { |
||
338 | fail[i] = 1; |
||
339 | mask[i] = 0; |
||
340 | } |
||
341 | } |
||
342 | else { |
||
343 | fail[i] = 0; |
||
344 | } |
||
345 | } |
||
346 | break; |
||
347 | case GL_EQUAL: |
||
348 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
349 | for (i=0;i<n;i++) { |
||
350 | if (mask[i]) { |
||
351 | s = (GLstencil) (stencil[i] & valueMask); |
||
352 | if (r == s) { |
||
353 | /* passed */ |
||
354 | fail[i] = 0; |
||
355 | } |
||
356 | else { |
||
357 | fail[i] = 1; |
||
358 | mask[i] = 0; |
||
359 | } |
||
360 | } |
||
361 | else { |
||
362 | fail[i] = 0; |
||
363 | } |
||
364 | } |
||
365 | break; |
||
366 | case GL_NOTEQUAL: |
||
367 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
368 | for (i=0;i<n;i++) { |
||
369 | if (mask[i]) { |
||
370 | s = (GLstencil) (stencil[i] & valueMask); |
||
371 | if (r != s) { |
||
372 | /* passed */ |
||
373 | fail[i] = 0; |
||
374 | } |
||
375 | else { |
||
376 | fail[i] = 1; |
||
377 | mask[i] = 0; |
||
378 | } |
||
379 | } |
||
380 | else { |
||
381 | fail[i] = 0; |
||
382 | } |
||
383 | } |
||
384 | break; |
||
385 | case GL_ALWAYS: |
||
386 | /* always pass */ |
||
387 | for (i=0;i<n;i++) { |
||
388 | fail[i] = 0; |
||
389 | } |
||
390 | break; |
||
391 | default: |
||
392 | _mesa_problem(ctx, "Bad stencil func in gl_stencil_span"); |
||
393 | return 0; |
||
394 | } |
||
395 | |||
396 | if (ctx->Stencil.FailFunc[face] != GL_KEEP) { |
||
397 | apply_stencil_op( ctx, ctx->Stencil.FailFunc[face], face, n, stencil, fail ); |
||
398 | } |
||
399 | |||
400 | return !allfail; |
||
401 | } |
||
402 | |||
403 | |||
404 | |||
405 | /** |
||
406 | * Apply stencil and depth testing to the span of pixels. |
||
407 | * Both software and hardware stencil buffers are acceptable. |
||
408 | * Input: n - number of pixels in the span |
||
409 | * x, y - location of leftmost pixel in span |
||
410 | * z - array [n] of z values |
||
411 | * mask - array [n] of flags (1=test this pixel, 0=skip the pixel) |
||
412 | * Output: mask - array [n] of flags (1=stencil and depth test passed) |
||
413 | * Return: GL_FALSE - all fragments failed the testing |
||
414 | * GL_TRUE - one or more fragments passed the testing |
||
415 | * |
||
416 | */ |
||
417 | static GLboolean |
||
418 | stencil_and_ztest_span(GLcontext *ctx, struct sw_span *span, GLuint face) |
||
419 | { |
||
420 | SWcontext *swrast = SWRAST_CONTEXT(ctx); |
||
421 | GLstencil stencilRow[MAX_WIDTH]; |
||
422 | GLstencil *stencil; |
||
423 | const GLuint n = span->end; |
||
424 | const GLint x = span->x; |
||
425 | const GLint y = span->y; |
||
426 | GLubyte *mask = span->array->mask; |
||
427 | |||
428 | ASSERT((span->arrayMask & SPAN_XY) == 0); |
||
429 | ASSERT(ctx->Stencil.Enabled); |
||
430 | ASSERT(n <= MAX_WIDTH); |
||
431 | #ifdef DEBUG |
||
432 | if (ctx->Depth.Test) { |
||
433 | ASSERT(span->arrayMask & SPAN_Z); |
||
434 | } |
||
435 | #endif |
||
436 | |||
437 | /* Get initial stencil values */ |
||
438 | if (swrast->Driver.WriteStencilSpan) { |
||
439 | /* Get stencil values from the hardware stencil buffer */ |
||
440 | ASSERT(swrast->Driver.ReadStencilSpan); |
||
441 | (*swrast->Driver.ReadStencilSpan)(ctx, n, x, y, stencilRow); |
||
442 | stencil = stencilRow; |
||
443 | } |
||
444 | else { |
||
445 | /* Get pointer into software stencil buffer */ |
||
446 | stencil = STENCIL_ADDRESS(x, y); |
||
447 | } |
||
448 | |||
449 | /* |
||
450 | * Apply the stencil test to the fragments. |
||
451 | * failMask[i] is 1 if the stencil test failed. |
||
452 | */ |
||
453 | if (do_stencil_test( ctx, face, n, stencil, mask ) == GL_FALSE) { |
||
454 | /* all fragments failed the stencil test, we're done. */ |
||
455 | span->writeAll = GL_FALSE; |
||
456 | return GL_FALSE; |
||
457 | } |
||
458 | |||
459 | /* |
||
460 | * Some fragments passed the stencil test, apply depth test to them |
||
461 | * and apply Zpass and Zfail stencil ops. |
||
462 | */ |
||
463 | if (ctx->Depth.Test == GL_FALSE) { |
||
464 | /* |
||
465 | * No depth buffer, just apply zpass stencil function to active pixels. |
||
466 | */ |
||
467 | apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face, n, stencil, mask ); |
||
468 | } |
||
469 | else { |
||
470 | /* |
||
471 | * Perform depth buffering, then apply zpass or zfail stencil function. |
||
472 | */ |
||
473 | GLubyte passmask[MAX_WIDTH], failmask[MAX_WIDTH], oldmask[MAX_WIDTH]; |
||
474 | GLuint i; |
||
475 | |||
476 | /* save the current mask bits */ |
||
477 | MEMCPY(oldmask, mask, n * sizeof(GLubyte)); |
||
478 | |||
479 | /* apply the depth test */ |
||
480 | _mesa_depth_test_span(ctx, span); |
||
481 | |||
482 | /* Set the stencil pass/fail flags according to result of depth testing. |
||
483 | * if oldmask[i] == 0 then |
||
484 | * Don't touch the stencil value |
||
485 | * else if oldmask[i] and newmask[i] then |
||
486 | * Depth test passed |
||
487 | * else |
||
488 | * assert(oldmask[i] && !newmask[i]) |
||
489 | * Depth test failed |
||
490 | * endif |
||
491 | */ |
||
492 | for (i=0;i<n;i++) { |
||
493 | ASSERT(mask[i] == 0 || mask[i] == 1); |
||
494 | passmask[i] = oldmask[i] & mask[i]; |
||
495 | failmask[i] = oldmask[i] & (mask[i] ^ 1); |
||
496 | } |
||
497 | |||
498 | /* apply the pass and fail operations */ |
||
499 | if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) { |
||
500 | apply_stencil_op( ctx, ctx->Stencil.ZFailFunc[face], face, |
||
501 | n, stencil, failmask ); |
||
502 | } |
||
503 | if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) { |
||
504 | apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face, |
||
505 | n, stencil, passmask ); |
||
506 | } |
||
507 | } |
||
508 | |||
509 | /* |
||
510 | * Write updated stencil values back into hardware stencil buffer. |
||
511 | */ |
||
512 | if (swrast->Driver.WriteStencilSpan) { |
||
513 | ASSERT(stencil == stencilRow); |
||
514 | (swrast->Driver.WriteStencilSpan)(ctx, n, x, y, stencil, mask ); |
||
515 | } |
||
516 | |||
517 | span->writeAll = GL_FALSE; |
||
518 | |||
519 | return GL_TRUE; /* one or more fragments passed both tests */ |
||
520 | } |
||
521 | |||
522 | |||
523 | |||
524 | |||
525 | /** |
||
526 | * Apply the given stencil operator for each pixel in the array whose |
||
527 | * mask flag is set. |
||
528 | * \note This is for software stencil buffers only. |
||
529 | * Input: n - number of pixels in the span |
||
530 | * x, y - array of [n] pixels |
||
531 | * operator - the stencil buffer operator |
||
532 | * mask - array [n] of flag: 1=apply operator, 0=don't apply operator |
||
533 | */ |
||
534 | static void |
||
535 | apply_stencil_op_to_pixels( const GLcontext *ctx, |
||
536 | GLuint n, const GLint x[], const GLint y[], |
||
537 | GLenum oper, GLuint face, const GLubyte mask[] ) |
||
538 | { |
||
539 | const GLstencil ref = ctx->Stencil.Ref[face]; |
||
540 | const GLstencil wrtmask = ctx->Stencil.WriteMask[face]; |
||
541 | const GLstencil invmask = (GLstencil) (~wrtmask); |
||
542 | GLuint i; |
||
543 | |||
544 | ASSERT(!SWRAST_CONTEXT(ctx)->Driver.WriteStencilSpan); /* software stencil buffer only! */ |
||
545 | |||
546 | switch (oper) { |
||
547 | case GL_KEEP: |
||
548 | /* do nothing */ |
||
549 | break; |
||
550 | case GL_ZERO: |
||
551 | if (invmask==0) { |
||
552 | for (i=0;i<n;i++) { |
||
553 | if (mask[i]) { |
||
554 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
555 | *sptr = 0; |
||
556 | } |
||
557 | } |
||
558 | } |
||
559 | else { |
||
560 | for (i=0;i<n;i++) { |
||
561 | if (mask[i]) { |
||
562 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
563 | *sptr = (GLstencil) (invmask & *sptr); |
||
564 | } |
||
565 | } |
||
566 | } |
||
567 | break; |
||
568 | case GL_REPLACE: |
||
569 | if (invmask==0) { |
||
570 | for (i=0;i<n;i++) { |
||
571 | if (mask[i]) { |
||
572 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
573 | *sptr = ref; |
||
574 | } |
||
575 | } |
||
576 | } |
||
577 | else { |
||
578 | for (i=0;i<n;i++) { |
||
579 | if (mask[i]) { |
||
580 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
581 | *sptr = (GLstencil) ((invmask & *sptr ) | (wrtmask & ref)); |
||
582 | } |
||
583 | } |
||
584 | } |
||
585 | break; |
||
586 | case GL_INCR: |
||
587 | if (invmask==0) { |
||
588 | for (i=0;i<n;i++) { |
||
589 | if (mask[i]) { |
||
590 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
591 | if (*sptr < STENCIL_MAX) { |
||
592 | *sptr = (GLstencil) (*sptr + 1); |
||
593 | } |
||
594 | } |
||
595 | } |
||
596 | } |
||
597 | else { |
||
598 | for (i=0;i<n;i++) { |
||
599 | if (mask[i]) { |
||
600 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
601 | if (*sptr < STENCIL_MAX) { |
||
602 | *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr+1))); |
||
603 | } |
||
604 | } |
||
605 | } |
||
606 | } |
||
607 | break; |
||
608 | case GL_DECR: |
||
609 | if (invmask==0) { |
||
610 | for (i=0;i<n;i++) { |
||
611 | if (mask[i]) { |
||
612 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
613 | if (*sptr>0) { |
||
614 | *sptr = (GLstencil) (*sptr - 1); |
||
615 | } |
||
616 | } |
||
617 | } |
||
618 | } |
||
619 | else { |
||
620 | for (i=0;i<n;i++) { |
||
621 | if (mask[i]) { |
||
622 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
623 | if (*sptr>0) { |
||
624 | *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr-1))); |
||
625 | } |
||
626 | } |
||
627 | } |
||
628 | } |
||
629 | break; |
||
630 | case GL_INCR_WRAP_EXT: |
||
631 | if (invmask==0) { |
||
632 | for (i=0;i<n;i++) { |
||
633 | if (mask[i]) { |
||
634 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
635 | *sptr = (GLstencil) (*sptr + 1); |
||
636 | } |
||
637 | } |
||
638 | } |
||
639 | else { |
||
640 | for (i=0;i<n;i++) { |
||
641 | if (mask[i]) { |
||
642 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
643 | *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr+1))); |
||
644 | } |
||
645 | } |
||
646 | } |
||
647 | break; |
||
648 | case GL_DECR_WRAP_EXT: |
||
649 | if (invmask==0) { |
||
650 | for (i=0;i<n;i++) { |
||
651 | if (mask[i]) { |
||
652 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
653 | *sptr = (GLstencil) (*sptr - 1); |
||
654 | } |
||
655 | } |
||
656 | } |
||
657 | else { |
||
658 | for (i=0;i<n;i++) { |
||
659 | if (mask[i]) { |
||
660 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
661 | *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr-1))); |
||
662 | } |
||
663 | } |
||
664 | } |
||
665 | break; |
||
666 | case GL_INVERT: |
||
667 | if (invmask==0) { |
||
668 | for (i=0;i<n;i++) { |
||
669 | if (mask[i]) { |
||
670 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
671 | *sptr = (GLstencil) (~*sptr); |
||
672 | } |
||
673 | } |
||
674 | } |
||
675 | else { |
||
676 | for (i=0;i<n;i++) { |
||
677 | if (mask[i]) { |
||
678 | GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] ); |
||
679 | *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & ~*sptr)); |
||
680 | } |
||
681 | } |
||
682 | } |
||
683 | break; |
||
684 | default: |
||
685 | _mesa_problem(ctx, "Bad stencilop in apply_stencil_op_to_pixels"); |
||
686 | } |
||
687 | } |
||
688 | |||
689 | |||
690 | |||
691 | /** |
||
692 | * Apply stencil test to an array of pixels before depth buffering. |
||
693 | * |
||
694 | * \note Used for software stencil buffer only. |
||
695 | * Input: n - number of pixels in the span |
||
696 | * x, y - array of [n] pixels to stencil |
||
697 | * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel |
||
698 | * Output: mask - pixels which fail the stencil test will have their |
||
699 | * mask flag set to 0. |
||
700 | * \return GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed. |
||
701 | */ |
||
702 | static GLboolean |
||
703 | stencil_test_pixels( GLcontext *ctx, GLuint face, GLuint n, |
||
704 | const GLint x[], const GLint y[], GLubyte mask[] ) |
||
705 | { |
||
706 | GLubyte fail[MAX_WIDTH]; |
||
707 | GLstencil r, s; |
||
708 | GLuint i; |
||
709 | GLboolean allfail = GL_FALSE; |
||
710 | const GLuint valueMask = ctx->Stencil.ValueMask[face]; |
||
711 | |||
712 | /* software stencil buffer only! */ |
||
713 | ASSERT(ctx->DrawBuffer->UseSoftwareStencilBuffer); |
||
714 | ASSERT(!SWRAST_CONTEXT(ctx)->Driver.ReadStencilSpan); |
||
715 | ASSERT(!SWRAST_CONTEXT(ctx)->Driver.WriteStencilSpan); |
||
716 | |||
717 | /* |
||
718 | * Perform stencil test. The results of this operation are stored |
||
719 | * in the fail[] array: |
||
720 | * IF fail[i] is non-zero THEN |
||
721 | * the stencil fail operator is to be applied |
||
722 | * ELSE |
||
723 | * the stencil fail operator is not to be applied |
||
724 | * ENDIF |
||
725 | */ |
||
726 | |||
727 | switch (ctx->Stencil.Function[face]) { |
||
728 | case GL_NEVER: |
||
729 | /* always fail */ |
||
730 | for (i=0;i<n;i++) { |
||
731 | if (mask[i]) { |
||
732 | mask[i] = 0; |
||
733 | fail[i] = 1; |
||
734 | } |
||
735 | else { |
||
736 | fail[i] = 0; |
||
737 | } |
||
738 | } |
||
739 | allfail = GL_TRUE; |
||
740 | break; |
||
741 | case GL_LESS: |
||
742 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
743 | for (i=0;i<n;i++) { |
||
744 | if (mask[i]) { |
||
745 | GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]); |
||
746 | s = (GLstencil) (*sptr & valueMask); |
||
747 | if (r < s) { |
||
748 | /* passed */ |
||
749 | fail[i] = 0; |
||
750 | } |
||
751 | else { |
||
752 | fail[i] = 1; |
||
753 | mask[i] = 0; |
||
754 | } |
||
755 | } |
||
756 | else { |
||
757 | fail[i] = 0; |
||
758 | } |
||
759 | } |
||
760 | break; |
||
761 | case GL_LEQUAL: |
||
762 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
763 | for (i=0;i<n;i++) { |
||
764 | if (mask[i]) { |
||
765 | GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]); |
||
766 | s = (GLstencil) (*sptr & valueMask); |
||
767 | if (r <= s) { |
||
768 | /* pass */ |
||
769 | fail[i] = 0; |
||
770 | } |
||
771 | else { |
||
772 | fail[i] = 1; |
||
773 | mask[i] = 0; |
||
774 | } |
||
775 | } |
||
776 | else { |
||
777 | fail[i] = 0; |
||
778 | } |
||
779 | } |
||
780 | break; |
||
781 | case GL_GREATER: |
||
782 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
783 | for (i=0;i<n;i++) { |
||
784 | if (mask[i]) { |
||
785 | GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]); |
||
786 | s = (GLstencil) (*sptr & valueMask); |
||
787 | if (r > s) { |
||
788 | /* passed */ |
||
789 | fail[i] = 0; |
||
790 | } |
||
791 | else { |
||
792 | fail[i] = 1; |
||
793 | mask[i] = 0; |
||
794 | } |
||
795 | } |
||
796 | else { |
||
797 | fail[i] = 0; |
||
798 | } |
||
799 | } |
||
800 | break; |
||
801 | case GL_GEQUAL: |
||
802 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
803 | for (i=0;i<n;i++) { |
||
804 | if (mask[i]) { |
||
805 | GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]); |
||
806 | s = (GLstencil) (*sptr & valueMask); |
||
807 | if (r >= s) { |
||
808 | /* passed */ |
||
809 | fail[i] = 0; |
||
810 | } |
||
811 | else { |
||
812 | fail[i] = 1; |
||
813 | mask[i] = 0; |
||
814 | } |
||
815 | } |
||
816 | else { |
||
817 | fail[i] = 0; |
||
818 | } |
||
819 | } |
||
820 | break; |
||
821 | case GL_EQUAL: |
||
822 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
823 | for (i=0;i<n;i++) { |
||
824 | if (mask[i]) { |
||
825 | GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]); |
||
826 | s = (GLstencil) (*sptr & valueMask); |
||
827 | if (r == s) { |
||
828 | /* passed */ |
||
829 | fail[i] = 0; |
||
830 | } |
||
831 | else { |
||
832 | fail[i] = 1; |
||
833 | mask[i] = 0; |
||
834 | } |
||
835 | } |
||
836 | else { |
||
837 | fail[i] = 0; |
||
838 | } |
||
839 | } |
||
840 | break; |
||
841 | case GL_NOTEQUAL: |
||
842 | r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask); |
||
843 | for (i=0;i<n;i++) { |
||
844 | if (mask[i]) { |
||
845 | GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]); |
||
846 | s = (GLstencil) (*sptr & valueMask); |
||
847 | if (r != s) { |
||
848 | /* passed */ |
||
849 | fail[i] = 0; |
||
850 | } |
||
851 | else { |
||
852 | fail[i] = 1; |
||
853 | mask[i] = 0; |
||
854 | } |
||
855 | } |
||
856 | else { |
||
857 | fail[i] = 0; |
||
858 | } |
||
859 | } |
||
860 | break; |
||
861 | case GL_ALWAYS: |
||
862 | /* always pass */ |
||
863 | for (i=0;i<n;i++) { |
||
864 | fail[i] = 0; |
||
865 | } |
||
866 | break; |
||
867 | default: |
||
868 | _mesa_problem(ctx, "Bad stencil func in gl_stencil_pixels"); |
||
869 | return 0; |
||
870 | } |
||
871 | |||
872 | if (ctx->Stencil.FailFunc[face] != GL_KEEP) { |
||
873 | apply_stencil_op_to_pixels( ctx, n, x, y, ctx->Stencil.FailFunc[face], |
||
874 | face, fail ); |
||
875 | } |
||
876 | |||
877 | return !allfail; |
||
878 | } |
||
879 | |||
880 | |||
881 | |||
882 | |||
883 | /** |
||
884 | * Apply stencil and depth testing to an array of pixels. |
||
885 | * This is used both for software and hardware stencil buffers. |
||
886 | * |
||
887 | * The comments in this function are a bit sparse but the code is |
||
888 | * almost identical to stencil_and_ztest_span(), which is well |
||
889 | * commented. |
||
890 | * |
||
891 | * Input: n - number of pixels in the array |
||
892 | * x, y - array of [n] pixel positions |
||
893 | * z - array [n] of z values |
||
894 | * mask - array [n] of flags (1=test this pixel, 0=skip the pixel) |
||
895 | * Output: mask - array [n] of flags (1=stencil and depth test passed) |
||
896 | * Return: GL_FALSE - all fragments failed the testing |
||
897 | * GL_TRUE - one or more fragments passed the testing |
||
898 | */ |
||
899 | static GLboolean |
||
900 | stencil_and_ztest_pixels( GLcontext *ctx, struct sw_span *span, GLuint face ) |
||
901 | { |
||
902 | const GLuint n = span->end; |
||
903 | const GLint *x = span->array->x; |
||
904 | const GLint *y = span->array->y; |
||
905 | GLubyte *mask = span->array->mask; |
||
906 | SWcontext *swrast = SWRAST_CONTEXT(ctx); |
||
907 | |||
908 | ASSERT(span->arrayMask & SPAN_XY); |
||
909 | ASSERT(ctx->Stencil.Enabled); |
||
910 | ASSERT(n <= MAX_WIDTH); |
||
911 | |||
912 | if (swrast->Driver.WriteStencilPixels) { |
||
913 | /*** Hardware stencil buffer ***/ |
||
914 | GLstencil stencil[MAX_WIDTH]; |
||
915 | GLubyte origMask[MAX_WIDTH]; |
||
916 | |||
917 | ASSERT(!ctx->DrawBuffer->UseSoftwareStencilBuffer); |
||
918 | ASSERT(swrast->Driver.ReadStencilPixels); |
||
919 | (*swrast->Driver.ReadStencilPixels)(ctx, n, x, y, stencil); |
||
920 | |||
921 | MEMCPY(origMask, mask, n * sizeof(GLubyte)); |
||
922 | |||
923 | (void) do_stencil_test(ctx, face, n, stencil, mask); |
||
924 | |||
925 | if (ctx->Depth.Test == GL_FALSE) { |
||
926 | apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face, |
||
927 | n, stencil, mask); |
||
928 | } |
||
929 | else { |
||
930 | _mesa_depth_test_span(ctx, span); |
||
931 | |||
932 | if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) { |
||
933 | GLubyte failmask[MAX_WIDTH]; |
||
934 | GLuint i; |
||
935 | for (i = 0; i < n; i++) { |
||
936 | ASSERT(mask[i] == 0 || mask[i] == 1); |
||
937 | failmask[i] = origMask[i] & (mask[i] ^ 1); |
||
938 | } |
||
939 | apply_stencil_op(ctx, ctx->Stencil.ZFailFunc[face], face, |
||
940 | n, stencil, failmask); |
||
941 | } |
||
942 | if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) { |
||
943 | GLubyte passmask[MAX_WIDTH]; |
||
944 | GLuint i; |
||
945 | for (i = 0; i < n; i++) { |
||
946 | ASSERT(mask[i] == 0 || mask[i] == 1); |
||
947 | passmask[i] = origMask[i] & mask[i]; |
||
948 | } |
||
949 | apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face, |
||
950 | n, stencil, passmask); |
||
951 | } |
||
952 | } |
||
953 | |||
954 | /* Write updated stencil values into hardware stencil buffer */ |
||
955 | (swrast->Driver.WriteStencilPixels)(ctx, n, x, y, stencil, origMask); |
||
956 | |||
957 | return GL_TRUE; |
||
958 | } |
||
959 | else { |
||
960 | /*** Software stencil buffer ***/ |
||
961 | |||
962 | ASSERT(ctx->DrawBuffer->UseSoftwareStencilBuffer); |
||
963 | |||
964 | if (stencil_test_pixels(ctx, face, n, x, y, mask) == GL_FALSE) { |
||
965 | /* all fragments failed the stencil test, we're done. */ |
||
966 | return GL_FALSE; |
||
967 | } |
||
968 | |||
969 | if (ctx->Depth.Test==GL_FALSE) { |
||
970 | apply_stencil_op_to_pixels(ctx, n, x, y, |
||
971 | ctx->Stencil.ZPassFunc[face], face, mask); |
||
972 | } |
||
973 | else { |
||
974 | GLubyte passmask[MAX_WIDTH], failmask[MAX_WIDTH], oldmask[MAX_WIDTH]; |
||
975 | GLuint i; |
||
976 | |||
977 | MEMCPY(oldmask, mask, n * sizeof(GLubyte)); |
||
978 | |||
979 | _mesa_depth_test_span(ctx, span); |
||
980 | |||
981 | for (i=0;i<n;i++) { |
||
982 | ASSERT(mask[i] == 0 || mask[i] == 1); |
||
983 | passmask[i] = oldmask[i] & mask[i]; |
||
984 | failmask[i] = oldmask[i] & (mask[i] ^ 1); |
||
985 | } |
||
986 | |||
987 | if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) { |
||
988 | apply_stencil_op_to_pixels(ctx, n, x, y, |
||
989 | ctx->Stencil.ZFailFunc[face], |
||
990 | face, failmask); |
||
991 | } |
||
992 | if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) { |
||
993 | apply_stencil_op_to_pixels(ctx, n, x, y, |
||
994 | ctx->Stencil.ZPassFunc[face], |
||
995 | face, passmask); |
||
996 | } |
||
997 | } |
||
998 | |||
999 | return GL_TRUE; /* one or more fragments passed both tests */ |
||
1000 | } |
||
1001 | } |
||
1002 | |||
1003 | |||
1004 | /** |
||
1005 | * /return GL_TRUE = one or more fragments passed, |
||
1006 | * GL_FALSE = all fragments failed. |
||
1007 | */ |
||
1008 | GLboolean |
||
1009 | _mesa_stencil_and_ztest_span(GLcontext *ctx, struct sw_span *span) |
||
1010 | { |
||
1011 | /* span->facing can only be non-zero if using two-sided stencil */ |
||
1012 | ASSERT(ctx->Stencil.TestTwoSide || span->facing == 0); |
||
1013 | if (span->arrayMask & SPAN_XY) |
||
1014 | return stencil_and_ztest_pixels(ctx, span, span->facing); |
||
1015 | else |
||
1016 | return stencil_and_ztest_span(ctx, span, span->facing); |
||
1017 | } |
||
1018 | |||
1019 | |||
1020 | /** |
||
1021 | * Return a span of stencil values from the stencil buffer. |
||
1022 | * Used for glRead/CopyPixels |
||
1023 | * Input: n - how many pixels |
||
1024 | * x,y - location of first pixel |
||
1025 | * Output: stencil - the array of stencil values |
||
1026 | */ |
||
1027 | void |
||
1028 | _mesa_read_stencil_span( GLcontext *ctx, |
||
1029 | GLint n, GLint x, GLint y, GLstencil stencil[] ) |
||
1030 | { |
||
1031 | SWcontext *swrast = SWRAST_CONTEXT(ctx); |
||
1032 | const GLint bufWidth = (GLint) ctx->DrawBuffer->Width; |
||
1033 | const GLint bufHeight = (GLint) ctx->DrawBuffer->Height; |
||
1034 | |||
1035 | if (y < 0 || y >= bufHeight || x + n <= 0 || x >= bufWidth) { |
||
1036 | /* span is completely outside framebuffer */ |
||
1037 | return; /* undefined values OK */ |
||
1038 | } |
||
1039 | |||
1040 | if (x < 0) { |
||
1041 | GLint dx = -x; |
||
1042 | x = 0; |
||
1043 | n -= dx; |
||
1044 | stencil += dx; |
||
1045 | } |
||
1046 | if (x + n > bufWidth) { |
||
1047 | GLint dx = x + n - bufWidth; |
||
1048 | n -= dx; |
||
1049 | } |
||
1050 | if (n <= 0) { |
||
1051 | return; |
||
1052 | } |
||
1053 | |||
1054 | |||
1055 | ASSERT(n >= 0); |
||
1056 | if (swrast->Driver.ReadStencilSpan) { |
||
1057 | (*swrast->Driver.ReadStencilSpan)( ctx, (GLuint) n, x, y, stencil ); |
||
1058 | } |
||
1059 | else if (ctx->DrawBuffer->Stencil) { |
||
1060 | const GLstencil *s = STENCIL_ADDRESS( x, y ); |
||
1061 | #if STENCIL_BITS == 8 |
||
1062 | MEMCPY( stencil, s, n * sizeof(GLstencil) ); |
||
1063 | #else |
||
1064 | GLuint i; |
||
1065 | for (i=0;i<n;i++) |
||
1066 | stencil[i] = s[i]; |
||
1067 | #endif |
||
1068 | } |
||
1069 | } |
||
1070 | |||
1071 | |||
1072 | |||
1073 | /** |
||
1074 | * Write a span of stencil values to the stencil buffer. |
||
1075 | * Used for glDraw/CopyPixels |
||
1076 | * Input: n - how many pixels |
||
1077 | * x, y - location of first pixel |
||
1078 | * stencil - the array of stencil values |
||
1079 | */ |
||
1080 | void |
||
1081 | _mesa_write_stencil_span( GLcontext *ctx, GLint n, GLint x, GLint y, |
||
1082 | const GLstencil stencil[] ) |
||
1083 | { |
||
1084 | SWcontext *swrast = SWRAST_CONTEXT(ctx); |
||
1085 | const GLstencil *ssrc = stencil; |
||
1086 | const GLint bufWidth = (GLint) ctx->DrawBuffer->Width; |
||
1087 | const GLint bufHeight = (GLint) ctx->DrawBuffer->Height; |
||
1088 | |||
1089 | if (y < 0 || y >= bufHeight || x + n <= 0 || x >= bufWidth) { |
||
1090 | /* span is completely outside framebuffer */ |
||
1091 | return; /* undefined values OK */ |
||
1092 | } |
||
1093 | |||
1094 | if (x < 0) { |
||
1095 | GLint dx = -x; |
||
1096 | x = 0; |
||
1097 | n -= dx; |
||
1098 | ssrc += dx; |
||
1099 | } |
||
1100 | if (x + n > bufWidth) { |
||
1101 | GLint dx = x + n - bufWidth; |
||
1102 | n -= dx; |
||
1103 | } |
||
1104 | if (n <= 0) { |
||
1105 | return; |
||
1106 | } |
||
1107 | |||
1108 | if (swrast->Driver.WriteStencilSpan) { |
||
1109 | (*swrast->Driver.WriteStencilSpan)( ctx, n, x, y, ssrc, NULL ); |
||
1110 | } |
||
1111 | else if (ctx->DrawBuffer->Stencil) { |
||
1112 | GLstencil *s = STENCIL_ADDRESS( x, y ); |
||
1113 | #if STENCIL_BITS == 8 |
||
1114 | MEMCPY( s, ssrc, n * sizeof(GLstencil) ); |
||
1115 | #else |
||
1116 | GLuint i; |
||
1117 | for (i=0;i<n;i++) |
||
1118 | s[i] = ssrc[i]; |
||
1119 | #endif |
||
1120 | } |
||
1121 | } |
||
1122 | |||
1123 | |||
1124 | |||
1125 | /** |
||
1126 | * Allocate a new stencil buffer. If there's an old one it will be |
||
1127 | * deallocated first. The new stencil buffer will be uninitialized. |
||
1128 | */ |
||
1129 | void |
||
1130 | _mesa_alloc_stencil_buffer( GLframebuffer *buffer ) |
||
1131 | { |
||
1132 | /* deallocate current stencil buffer if present */ |
||
1133 | if (buffer->Stencil) { |
||
1134 | MESA_PBUFFER_FREE(buffer->Stencil); |
||
1135 | buffer->Stencil = NULL; |
||
1136 | } |
||
1137 | |||
1138 | /* allocate new stencil buffer */ |
||
1139 | buffer->Stencil = (GLstencil *) |
||
1140 | MESA_PBUFFER_ALLOC(buffer->Width * buffer->Height * sizeof(GLstencil)); |
||
1141 | if (!buffer->Stencil) { |
||
1142 | /* out of memory */ |
||
1143 | _mesa_error( NULL, GL_OUT_OF_MEMORY, "_mesa_alloc_stencil_buffer" ); |
||
1144 | } |
||
1145 | } |
||
1146 | |||
1147 | |||
1148 | |||
1149 | /** |
||
1150 | * Clear the software (malloc'd) stencil buffer. |
||
1151 | */ |
||
1152 | static void |
||
1153 | clear_software_stencil_buffer( GLcontext *ctx ) |
||
1154 | { |
||
1155 | if (ctx->Visual.stencilBits==0 || !ctx->DrawBuffer->Stencil) { |
||
1156 | /* no stencil buffer */ |
||
1157 | return; |
||
1158 | } |
||
1159 | |||
1160 | if (ctx->Scissor.Enabled) { |
||
1161 | /* clear scissor region only */ |
||
1162 | const GLint width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin; |
||
1163 | if (ctx->Stencil.WriteMask[0] != STENCIL_MAX) { |
||
1164 | /* must apply mask to the clear */ |
||
1165 | GLint y; |
||
1166 | for (y = ctx->DrawBuffer->_Ymin; y < ctx->DrawBuffer->_Ymax; y++) { |
||
1167 | const GLstencil mask = ctx->Stencil.WriteMask[0]; |
||
1168 | const GLstencil invMask = ~mask; |
||
1169 | const GLstencil clearVal = (ctx->Stencil.Clear & mask); |
||
1170 | GLstencil *stencil = STENCIL_ADDRESS( ctx->DrawBuffer->_Xmin, y ); |
||
1171 | GLint i; |
||
1172 | for (i = 0; i < width; i++) { |
||
1173 | stencil[i] = (stencil[i] & invMask) | clearVal; |
||
1174 | } |
||
1175 | } |
||
1176 | } |
||
1177 | else { |
||
1178 | /* no masking */ |
||
1179 | GLint y; |
||
1180 | for (y = ctx->DrawBuffer->_Ymin; y < ctx->DrawBuffer->_Ymax; y++) { |
||
1181 | GLstencil *stencil = STENCIL_ADDRESS( ctx->DrawBuffer->_Xmin, y ); |
||
1182 | #if STENCIL_BITS==8 |
||
1183 | MEMSET( stencil, ctx->Stencil.Clear, width * sizeof(GLstencil) ); |
||
1184 | #else |
||
1185 | GLint i; |
||
1186 | for (i = 0; i < width; i++) |
||
1187 | stencil[x] = ctx->Stencil.Clear; |
||
1188 | #endif |
||
1189 | } |
||
1190 | } |
||
1191 | } |
||
1192 | else { |
||
1193 | /* clear whole stencil buffer */ |
||
1194 | if (ctx->Stencil.WriteMask[0] != STENCIL_MAX) { |
||
1195 | /* must apply mask to the clear */ |
||
1196 | const GLuint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height; |
||
1197 | GLstencil *stencil = ctx->DrawBuffer->Stencil; |
||
1198 | const GLstencil mask = ctx->Stencil.WriteMask[0]; |
||
1199 | const GLstencil invMask = ~mask; |
||
1200 | const GLstencil clearVal = (ctx->Stencil.Clear & mask); |
||
1201 | GLuint i; |
||
1202 | for (i = 0; i < n; i++) { |
||
1203 | stencil[i] = (stencil[i] & invMask) | clearVal; |
||
1204 | } |
||
1205 | } |
||
1206 | else { |
||
1207 | /* clear whole buffer without masking */ |
||
1208 | const GLuint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height; |
||
1209 | GLstencil *stencil = ctx->DrawBuffer->Stencil; |
||
1210 | |||
1211 | #if STENCIL_BITS==8 |
||
1212 | MEMSET(stencil, ctx->Stencil.Clear, n * sizeof(GLstencil) ); |
||
1213 | #else |
||
1214 | GLuint i; |
||
1215 | for (i = 0; i < n; i++) { |
||
1216 | stencil[i] = ctx->Stencil.Clear; |
||
1217 | } |
||
1218 | #endif |
||
1219 | } |
||
1220 | } |
||
1221 | } |
||
1222 | |||
1223 | |||
1224 | |||
1225 | /** |
||
1226 | * Clear the hardware (in graphics card) stencil buffer. |
||
1227 | * This is done with the Driver.WriteStencilSpan() and Driver.ReadStencilSpan() |
||
1228 | * functions. |
||
1229 | * Actually, if there is a hardware stencil buffer it really should have |
||
1230 | * been cleared in Driver.Clear()! However, if the hardware does not |
||
1231 | * support scissored clears or masked clears (i.e. glStencilMask) then |
||
1232 | * we have to use the span-based functions. |
||
1233 | */ |
||
1234 | static void |
||
1235 | clear_hardware_stencil_buffer( GLcontext *ctx ) |
||
1236 | { |
||
1237 | SWcontext *swrast = SWRAST_CONTEXT(ctx); |
||
1238 | ASSERT(swrast->Driver.WriteStencilSpan); |
||
1239 | ASSERT(swrast->Driver.ReadStencilSpan); |
||
1240 | |||
1241 | if (ctx->Scissor.Enabled) { |
||
1242 | /* clear scissor region only */ |
||
1243 | const GLint x = ctx->DrawBuffer->_Xmin; |
||
1244 | const GLint width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin; |
||
1245 | if (ctx->Stencil.WriteMask[0] != STENCIL_MAX) { |
||
1246 | /* must apply mask to the clear */ |
||
1247 | GLint y; |
||
1248 | for (y = ctx->DrawBuffer->_Ymin; y < ctx->DrawBuffer->_Ymax; y++) { |
||
1249 | const GLstencil mask = ctx->Stencil.WriteMask[0]; |
||
1250 | const GLstencil invMask = ~mask; |
||
1251 | const GLstencil clearVal = (ctx->Stencil.Clear & mask); |
||
1252 | GLstencil stencil[MAX_WIDTH]; |
||
1253 | GLint i; |
||
1254 | (*swrast->Driver.ReadStencilSpan)(ctx, width, x, y, stencil); |
||
1255 | for (i = 0; i < width; i++) { |
||
1256 | stencil[i] = (stencil[i] & invMask) | clearVal; |
||
1257 | } |
||
1258 | (*swrast->Driver.WriteStencilSpan)(ctx, width, x, y, stencil, NULL); |
||
1259 | } |
||
1260 | } |
||
1261 | else { |
||
1262 | /* no masking */ |
||
1263 | GLstencil stencil[MAX_WIDTH]; |
||
1264 | GLint y, i; |
||
1265 | for (i = 0; i < width; i++) { |
||
1266 | stencil[i] = ctx->Stencil.Clear; |
||
1267 | } |
||
1268 | for (y = ctx->DrawBuffer->_Ymin; y < ctx->DrawBuffer->_Ymax; y++) { |
||
1269 | (*swrast->Driver.WriteStencilSpan)(ctx, width, x, y, stencil, NULL); |
||
1270 | } |
||
1271 | } |
||
1272 | } |
||
1273 | else { |
||
1274 | /* clear whole stencil buffer */ |
||
1275 | if (ctx->Stencil.WriteMask[0] != STENCIL_MAX) { |
||
1276 | /* must apply mask to the clear */ |
||
1277 | const GLstencil mask = ctx->Stencil.WriteMask[0]; |
||
1278 | const GLstencil invMask = ~mask; |
||
1279 | const GLstencil clearVal = (ctx->Stencil.Clear & mask); |
||
1280 | const GLint width = ctx->DrawBuffer->Width; |
||
1281 | const GLint height = ctx->DrawBuffer->Height; |
||
1282 | const GLint x = ctx->DrawBuffer->_Xmin; |
||
1283 | GLint y; |
||
1284 | for (y = 0; y < height; y++) { |
||
1285 | GLstencil stencil[MAX_WIDTH]; |
||
1286 | GLint i; |
||
1287 | (*swrast->Driver.ReadStencilSpan)(ctx, width, x, y, stencil); |
||
1288 | for (i = 0; i < width; i++) { |
||
1289 | stencil[i] = (stencil[i] & invMask) | clearVal; |
||
1290 | } |
||
1291 | (*swrast->Driver.WriteStencilSpan)(ctx, width, x, y, stencil, NULL); |
||
1292 | } |
||
1293 | } |
||
1294 | else { |
||
1295 | /* clear whole buffer without masking */ |
||
1296 | const GLint width = ctx->DrawBuffer->Width; |
||
1297 | const GLint height = ctx->DrawBuffer->Height; |
||
1298 | const GLint x = ctx->DrawBuffer->_Xmin; |
||
1299 | GLstencil stencil[MAX_WIDTH]; |
||
1300 | GLint y, i; |
||
1301 | for (i = 0; i < width; i++) { |
||
1302 | stencil[i] = ctx->Stencil.Clear; |
||
1303 | } |
||
1304 | for (y = 0; y < height; y++) { |
||
1305 | (*swrast->Driver.WriteStencilSpan)(ctx, width, x, y, stencil, NULL); |
||
1306 | } |
||
1307 | } |
||
1308 | } |
||
1309 | } |
||
1310 | |||
1311 | |||
1312 | |||
1313 | /** |
||
1314 | * Clear the stencil buffer (hardware or software). |
||
1315 | */ |
||
1316 | void |
||
1317 | _mesa_clear_stencil_buffer( GLcontext *ctx ) |
||
1318 | { |
||
1319 | SWcontext *swrast = SWRAST_CONTEXT(ctx); |
||
1320 | if (swrast->Driver.WriteStencilSpan) { |
||
1321 | ASSERT(swrast->Driver.ReadStencilSpan); |
||
1322 | clear_hardware_stencil_buffer(ctx); |
||
1323 | } |
||
1324 | else { |
||
1325 | clear_software_stencil_buffer(ctx); |
||
1326 | } |
||
1327 | } |