1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
5 * Copyright (C) 2009 VMware, Inc. 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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26 /**
27 * \file feedback.c
28 * Selection and feedback modes functions.
29 */
30
31
32 #include "glheader.h"
33 #include "context.h"
34 #include "enums.h"
35 #include "feedback.h"
36 #include "macros.h"
37 #include "mtypes.h"
38 #include "main/dispatch.h"
39
40
41 #define FB_3D 0x01
42 #define FB_4D 0x02
43 #define FB_COLOR 0x04
44 #define FB_TEXTURE 0X08
45
46
47
48 void GLAPIENTRY
_mesa_FeedbackBuffer(GLsizei size,GLenum type,GLfloat * buffer)49 _mesa_FeedbackBuffer( GLsizei size, GLenum type, GLfloat *buffer )
50 {
51 GET_CURRENT_CONTEXT(ctx);
52
53 if (ctx->RenderMode==GL_FEEDBACK) {
54 _mesa_error( ctx, GL_INVALID_OPERATION, "glFeedbackBuffer" );
55 return;
56 }
57 if (size<0) {
58 _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(size<0)" );
59 return;
60 }
61 if (!buffer && size > 0) {
62 _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(buffer==NULL)" );
63 ctx->Feedback.BufferSize = 0;
64 return;
65 }
66
67 switch (type) {
68 case GL_2D:
69 ctx->Feedback._Mask = 0;
70 break;
71 case GL_3D:
72 ctx->Feedback._Mask = FB_3D;
73 break;
74 case GL_3D_COLOR:
75 ctx->Feedback._Mask = (FB_3D | FB_COLOR);
76 break;
77 case GL_3D_COLOR_TEXTURE:
78 ctx->Feedback._Mask = (FB_3D | FB_COLOR | FB_TEXTURE);
79 break;
80 case GL_4D_COLOR_TEXTURE:
81 ctx->Feedback._Mask = (FB_3D | FB_4D | FB_COLOR | FB_TEXTURE);
82 break;
83 default:
84 _mesa_error( ctx, GL_INVALID_ENUM, "glFeedbackBuffer" );
85 return;
86 }
87
88 FLUSH_VERTICES(ctx, _NEW_RENDERMODE); /* Always flush */
89 ctx->Feedback.Type = type;
90 ctx->Feedback.BufferSize = size;
91 ctx->Feedback.Buffer = buffer;
92 ctx->Feedback.Count = 0; /* Because of this. */
93 }
94
95
96 void GLAPIENTRY
_mesa_PassThrough(GLfloat token)97 _mesa_PassThrough( GLfloat token )
98 {
99 GET_CURRENT_CONTEXT(ctx);
100
101 if (ctx->RenderMode==GL_FEEDBACK) {
102 FLUSH_VERTICES(ctx, 0);
103 _mesa_feedback_token( ctx, (GLfloat) (GLint) GL_PASS_THROUGH_TOKEN );
104 _mesa_feedback_token( ctx, token );
105 }
106 }
107
108
109 /**
110 * Put a vertex into the feedback buffer.
111 */
112 void
_mesa_feedback_vertex(struct gl_context * ctx,const GLfloat win[4],const GLfloat color[4],const GLfloat texcoord[4])113 _mesa_feedback_vertex(struct gl_context *ctx,
114 const GLfloat win[4],
115 const GLfloat color[4],
116 const GLfloat texcoord[4])
117 {
118 _mesa_feedback_token( ctx, win[0] );
119 _mesa_feedback_token( ctx, win[1] );
120 if (ctx->Feedback._Mask & FB_3D) {
121 _mesa_feedback_token( ctx, win[2] );
122 }
123 if (ctx->Feedback._Mask & FB_4D) {
124 _mesa_feedback_token( ctx, win[3] );
125 }
126 if (ctx->Feedback._Mask & FB_COLOR) {
127 _mesa_feedback_token( ctx, color[0] );
128 _mesa_feedback_token( ctx, color[1] );
129 _mesa_feedback_token( ctx, color[2] );
130 _mesa_feedback_token( ctx, color[3] );
131 }
132 if (ctx->Feedback._Mask & FB_TEXTURE) {
133 _mesa_feedback_token( ctx, texcoord[0] );
134 _mesa_feedback_token( ctx, texcoord[1] );
135 _mesa_feedback_token( ctx, texcoord[2] );
136 _mesa_feedback_token( ctx, texcoord[3] );
137 }
138 }
139
140
141 /**********************************************************************/
142 /** \name Selection */
143 /*@{*/
144
145 /**
146 * Establish a buffer for selection mode values.
147 *
148 * \param size buffer size.
149 * \param buffer buffer.
150 *
151 * \sa glSelectBuffer().
152 *
153 * \note this function can't be put in a display list.
154 *
155 * Verifies we're not in selection mode, flushes the vertices and initialize
156 * the fields in __struct gl_contextRec::Select with the given buffer.
157 */
158 void GLAPIENTRY
_mesa_SelectBuffer(GLsizei size,GLuint * buffer)159 _mesa_SelectBuffer( GLsizei size, GLuint *buffer )
160 {
161 GET_CURRENT_CONTEXT(ctx);
162
163 if (size < 0) {
164 _mesa_error(ctx, GL_INVALID_VALUE, "glSelectBuffer(size)");
165 return;
166 }
167
168 if (ctx->RenderMode==GL_SELECT) {
169 _mesa_error( ctx, GL_INVALID_OPERATION, "glSelectBuffer" );
170 return; /* KW: added return */
171 }
172
173 FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
174 ctx->Select.Buffer = buffer;
175 ctx->Select.BufferSize = size;
176 ctx->Select.BufferCount = 0;
177 ctx->Select.HitFlag = GL_FALSE;
178 ctx->Select.HitMinZ = 1.0;
179 ctx->Select.HitMaxZ = 0.0;
180 }
181
182
183 /**
184 * Write a value of a record into the selection buffer.
185 *
186 * \param ctx GL context.
187 * \param value value.
188 *
189 * Verifies there is free space in the buffer to write the value and
190 * increments the pointer.
191 */
192 static inline void
write_record(struct gl_context * ctx,GLuint value)193 write_record(struct gl_context *ctx, GLuint value)
194 {
195 if (ctx->Select.BufferCount < ctx->Select.BufferSize) {
196 ctx->Select.Buffer[ctx->Select.BufferCount] = value;
197 }
198 ctx->Select.BufferCount++;
199 }
200
201
202 /**
203 * Update the hit flag and the maximum and minimum depth values.
204 *
205 * \param ctx GL context.
206 * \param z depth.
207 *
208 * Sets gl_selection::HitFlag and updates gl_selection::HitMinZ and
209 * gl_selection::HitMaxZ.
210 */
211 void
_mesa_update_hitflag(struct gl_context * ctx,GLfloat z)212 _mesa_update_hitflag(struct gl_context *ctx, GLfloat z)
213 {
214 ctx->Select.HitFlag = GL_TRUE;
215 if (z < ctx->Select.HitMinZ) {
216 ctx->Select.HitMinZ = z;
217 }
218 if (z > ctx->Select.HitMaxZ) {
219 ctx->Select.HitMaxZ = z;
220 }
221 }
222
223
224 /**
225 * Write the hit record.
226 *
227 * \param ctx GL context.
228 *
229 * Write the hit record, i.e., the number of names in the stack, the minimum and
230 * maximum depth values and the number of names in the name stack at the time
231 * of the event. Resets the hit flag.
232 *
233 * \sa gl_selection.
234 */
235 static void
write_hit_record(struct gl_context * ctx)236 write_hit_record(struct gl_context *ctx)
237 {
238 GLuint i;
239 GLuint zmin, zmax, zscale = (~0u);
240
241 /* HitMinZ and HitMaxZ are in [0,1]. Multiply these values by */
242 /* 2^32-1 and round to nearest unsigned integer. */
243
244 assert( ctx != NULL ); /* this line magically fixes a SunOS 5.x/gcc bug */
245 zmin = (GLuint) ((GLfloat) zscale * ctx->Select.HitMinZ);
246 zmax = (GLuint) ((GLfloat) zscale * ctx->Select.HitMaxZ);
247
248 write_record( ctx, ctx->Select.NameStackDepth );
249 write_record( ctx, zmin );
250 write_record( ctx, zmax );
251 for (i = 0; i < ctx->Select.NameStackDepth; i++) {
252 write_record( ctx, ctx->Select.NameStack[i] );
253 }
254
255 ctx->Select.Hits++;
256 ctx->Select.HitFlag = GL_FALSE;
257 ctx->Select.HitMinZ = 1.0;
258 ctx->Select.HitMaxZ = -1.0;
259 }
260
261
262 /**
263 * Initialize the name stack.
264 *
265 * Verifies we are in select mode and resets the name stack depth and resets
266 * the hit record data in gl_selection. Marks new render mode in
267 * __struct gl_contextRec::NewState.
268 */
269 void GLAPIENTRY
_mesa_InitNames(void)270 _mesa_InitNames( void )
271 {
272 GET_CURRENT_CONTEXT(ctx);
273 FLUSH_VERTICES(ctx, 0);
274
275 /* Record the hit before the HitFlag is wiped out again. */
276 if (ctx->RenderMode == GL_SELECT) {
277 if (ctx->Select.HitFlag) {
278 write_hit_record( ctx );
279 }
280 }
281 ctx->Select.NameStackDepth = 0;
282 ctx->Select.HitFlag = GL_FALSE;
283 ctx->Select.HitMinZ = 1.0;
284 ctx->Select.HitMaxZ = 0.0;
285 ctx->NewState |= _NEW_RENDERMODE;
286 }
287
288
289 /**
290 * Load the top-most name of the name stack.
291 *
292 * \param name name.
293 *
294 * Verifies we are in selection mode and that the name stack is not empty.
295 * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
296 * and replace the top-most name in the stack.
297 *
298 * sa __struct gl_contextRec::Select.
299 */
300 void GLAPIENTRY
_mesa_LoadName(GLuint name)301 _mesa_LoadName( GLuint name )
302 {
303 GET_CURRENT_CONTEXT(ctx);
304
305 if (ctx->RenderMode != GL_SELECT) {
306 return;
307 }
308 if (ctx->Select.NameStackDepth == 0) {
309 _mesa_error( ctx, GL_INVALID_OPERATION, "glLoadName" );
310 return;
311 }
312
313 FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
314
315 if (ctx->Select.HitFlag) {
316 write_hit_record( ctx );
317 }
318 if (ctx->Select.NameStackDepth < MAX_NAME_STACK_DEPTH) {
319 ctx->Select.NameStack[ctx->Select.NameStackDepth-1] = name;
320 }
321 else {
322 ctx->Select.NameStack[MAX_NAME_STACK_DEPTH-1] = name;
323 }
324 }
325
326
327 /**
328 * Push a name into the name stack.
329 *
330 * \param name name.
331 *
332 * Verifies we are in selection mode and that the name stack is not full.
333 * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
334 * and adds the name to the top of the name stack.
335 *
336 * sa __struct gl_contextRec::Select.
337 */
338 void GLAPIENTRY
_mesa_PushName(GLuint name)339 _mesa_PushName( GLuint name )
340 {
341 GET_CURRENT_CONTEXT(ctx);
342
343 if (ctx->RenderMode != GL_SELECT) {
344 return;
345 }
346
347 FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
348 if (ctx->Select.HitFlag) {
349 write_hit_record( ctx );
350 }
351 if (ctx->Select.NameStackDepth >= MAX_NAME_STACK_DEPTH) {
352 _mesa_error( ctx, GL_STACK_OVERFLOW, "glPushName" );
353 }
354 else
355 ctx->Select.NameStack[ctx->Select.NameStackDepth++] = name;
356 }
357
358
359 /**
360 * Pop a name into the name stack.
361 *
362 * Verifies we are in selection mode and that the name stack is not empty.
363 * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
364 * and removes top-most name in the name stack.
365 *
366 * sa __struct gl_contextRec::Select.
367 */
368 void GLAPIENTRY
_mesa_PopName(void)369 _mesa_PopName( void )
370 {
371 GET_CURRENT_CONTEXT(ctx);
372
373 if (ctx->RenderMode != GL_SELECT) {
374 return;
375 }
376
377 FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
378 if (ctx->Select.HitFlag) {
379 write_hit_record( ctx );
380 }
381 if (ctx->Select.NameStackDepth == 0) {
382 _mesa_error( ctx, GL_STACK_UNDERFLOW, "glPopName" );
383 }
384 else
385 ctx->Select.NameStackDepth--;
386 }
387
388 /*@}*/
389
390
391 /**********************************************************************/
392 /** \name Render Mode */
393 /*@{*/
394
395 /**
396 * Set rasterization mode.
397 *
398 * \param mode rasterization mode.
399 *
400 * \note this function can't be put in a display list.
401 *
402 * \sa glRenderMode().
403 *
404 * Flushes the vertices and do the necessary cleanup according to the previous
405 * rasterization mode, such as writing the hit record or resent the select
406 * buffer index when exiting the select mode. Updates
407 * __struct gl_contextRec::RenderMode and notifies the driver via the
408 * dd_function_table::RenderMode callback.
409 */
410 GLint GLAPIENTRY
_mesa_RenderMode(GLenum mode)411 _mesa_RenderMode( GLenum mode )
412 {
413 GET_CURRENT_CONTEXT(ctx);
414 GLint result;
415 ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, 0);
416
417 if (MESA_VERBOSE & VERBOSE_API)
418 _mesa_debug(ctx, "glRenderMode %s\n", _mesa_enum_to_string(mode));
419
420 FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
421
422 switch (ctx->RenderMode) {
423 case GL_RENDER:
424 result = 0;
425 break;
426 case GL_SELECT:
427 if (ctx->Select.HitFlag) {
428 write_hit_record( ctx );
429 }
430 if (ctx->Select.BufferCount > ctx->Select.BufferSize) {
431 /* overflow */
432 #ifdef DEBUG
433 _mesa_warning(ctx, "Feedback buffer overflow");
434 #endif
435 result = -1;
436 }
437 else {
438 result = ctx->Select.Hits;
439 }
440 ctx->Select.BufferCount = 0;
441 ctx->Select.Hits = 0;
442 ctx->Select.NameStackDepth = 0;
443 break;
444 case GL_FEEDBACK:
445 if (ctx->Feedback.Count > ctx->Feedback.BufferSize) {
446 /* overflow */
447 result = -1;
448 }
449 else {
450 result = ctx->Feedback.Count;
451 }
452 ctx->Feedback.Count = 0;
453 break;
454 default:
455 _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
456 return 0;
457 }
458
459 switch (mode) {
460 case GL_RENDER:
461 break;
462 case GL_SELECT:
463 if (ctx->Select.BufferSize==0) {
464 /* haven't called glSelectBuffer yet */
465 _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
466 }
467 break;
468 case GL_FEEDBACK:
469 if (ctx->Feedback.BufferSize==0) {
470 /* haven't called glFeedbackBuffer yet */
471 _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
472 }
473 break;
474 default:
475 _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
476 return 0;
477 }
478
479 ctx->RenderMode = mode;
480 if (ctx->Driver.RenderMode)
481 ctx->Driver.RenderMode( ctx, mode );
482
483 return result;
484 }
485
486 /*@}*/
487
488
489 /**********************************************************************/
490 /** \name Initialization */
491 /*@{*/
492
493 /**
494 * Initialize context feedback data.
495 */
_mesa_init_feedback(struct gl_context * ctx)496 void _mesa_init_feedback( struct gl_context * ctx )
497 {
498 /* Feedback */
499 ctx->Feedback.Type = GL_2D; /* TODO: verify */
500 ctx->Feedback.Buffer = NULL;
501 ctx->Feedback.BufferSize = 0;
502 ctx->Feedback.Count = 0;
503
504 /* Selection/picking */
505 ctx->Select.Buffer = NULL;
506 ctx->Select.BufferSize = 0;
507 ctx->Select.BufferCount = 0;
508 ctx->Select.Hits = 0;
509 ctx->Select.NameStackDepth = 0;
510
511 /* Miscellaneous */
512 ctx->RenderMode = GL_RENDER;
513 }
514
515 /*@}*/
516