src/mesa/main/feedback.c

   1 /**
   2  * \file feedback.c
   3  * Selection and feedback modes functions.
   4  */
   5
   6 /*
   7  * Mesa 3-D graphics library
   8  * Version:  5.1
   9  *
  10  * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a
  13  * copy of this software and associated documentation files (the "Software"),
  14  * to deal in the Software without restriction, including without limitation
  15  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  16  * and/or sell copies of the Software, and to permit persons to whom the
  17  * Software is furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included
  20  * in all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  23  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  26  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  27  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28  */
  29
  30
  31 #include "glheader.h"
  32 #include "colormac.h"
  33 #include "context.h"
  34 #include "enums.h"
  35 #include "feedback.h"
  36 #include "macros.h"
  37 #include "mtypes.h"
  38
  39
  40 #if _HAVE_FULL_GL
  41
  42
  43 #define FB_3D           0x01
  44 #define FB_4D           0x02
  45 #define FB_INDEX        0x04
  46 #define FB_COLOR        0x08
  47 #define FB_TEXTURE      0X10
  48
  49
  50
  51 void GLAPIENTRY
  52 _mesa_FeedbackBuffer( GLsizei size, GLenum type, GLfloat *buffer )
  53 {
  54    GET_CURRENT_CONTEXT(ctx);
  55    ASSERT_OUTSIDE_BEGIN_END(ctx);
  56
  57    if (ctx->RenderMode==GL_FEEDBACK) {
  58       _mesa_error( ctx, GL_INVALID_OPERATION, "glFeedbackBuffer" );
  59       return;
  60    }
  61    if (size<0) {
  62       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(size<0)" );
  63       return;
  64    }
  65    if (!buffer) {
  66       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(buffer==NULL)" );
  67       ctx->Feedback.BufferSize = 0;
  68       return;
  69    }
  70
  71    switch (type) {
  72       case GL_2D:
  73          ctx->Feedback._Mask = 0;
  74          break;
  75       case GL_3D:
  76          ctx->Feedback._Mask = FB_3D;
  77          break;
  78       case GL_3D_COLOR:
  79          ctx->Feedback._Mask = (FB_3D |
  80                                 (ctx->Visual.rgbMode ? FB_COLOR : FB_INDEX));
  81          break;
  82       case GL_3D_COLOR_TEXTURE:
  83          ctx->Feedback._Mask = (FB_3D |
  84                                 (ctx->Visual.rgbMode ? FB_COLOR : FB_INDEX) |
  85                                 FB_TEXTURE);
  86          break;
  87       case GL_4D_COLOR_TEXTURE:
  88          ctx->Feedback._Mask = (FB_3D | FB_4D |
  89                                 (ctx->Visual.rgbMode ? FB_COLOR : FB_INDEX) |
  90                                 FB_TEXTURE);
  91          break;
  92       default:
  93          _mesa_error( ctx, GL_INVALID_ENUM, "glFeedbackBuffer" );
  94          return;
  95    }
  96
  97    FLUSH_VERTICES(ctx, _NEW_RENDERMODE); /* Always flush */
  98    ctx->Feedback.Type = type;
  99    ctx->Feedback.BufferSize = size;
 100    ctx->Feedback.Buffer = buffer;
 101    ctx->Feedback.Count = 0;                   /* Becaues of this. */
 102 }
 103
 104
 105 void GLAPIENTRY
 106 _mesa_PassThrough( GLfloat token )
 107 {
 108    GET_CURRENT_CONTEXT(ctx);
 109    ASSERT_OUTSIDE_BEGIN_END(ctx);
 110
 111    if (ctx->RenderMode==GL_FEEDBACK) {
 112       FLUSH_VERTICES(ctx, 0);
 113       FEEDBACK_TOKEN( ctx, (GLfloat) (GLint) GL_PASS_THROUGH_TOKEN );
 114       FEEDBACK_TOKEN( ctx, token );
 115    }
 116 }
 117
 118
 119
 120 /*
 121  * Put a vertex into the feedback buffer.
 122  */
 123 void _mesa_feedback_vertex( GLcontext *ctx,
 124                          const GLfloat win[4],
 125                          const GLfloat color[4],
 126                          GLuint index,
 127                          const GLfloat texcoord[4] )
 128 {
 129    FEEDBACK_TOKEN( ctx, win[0] );
 130    FEEDBACK_TOKEN( ctx, win[1] );
 131    if (ctx->Feedback._Mask & FB_3D) {
 132       FEEDBACK_TOKEN( ctx, win[2] );
 133    }
 134    if (ctx->Feedback._Mask & FB_4D) {
 135       FEEDBACK_TOKEN( ctx, win[3] );
 136    }
 137    if (ctx->Feedback._Mask & FB_INDEX) {
 138       FEEDBACK_TOKEN( ctx, (GLfloat) index );
 139    }
 140    if (ctx->Feedback._Mask & FB_COLOR) {
 141       FEEDBACK_TOKEN( ctx, color[0] );
 142       FEEDBACK_TOKEN( ctx, color[1] );
 143       FEEDBACK_TOKEN( ctx, color[2] );
 144       FEEDBACK_TOKEN( ctx, color[3] );
 145    }
 146    if (ctx->Feedback._Mask & FB_TEXTURE) {
 147       FEEDBACK_TOKEN( ctx, texcoord[0] );
 148       FEEDBACK_TOKEN( ctx, texcoord[1] );
 149       FEEDBACK_TOKEN( ctx, texcoord[2] );
 150       FEEDBACK_TOKEN( ctx, texcoord[3] );
 151    }
 152 }
 153
 154 #endif
 155
 156
 157 /**********************************************************************/
 158 /** \name Selection */
 159 /*@{*/
 160
 161 /**
 162  * Establish a buffer for selection mode values.
 163  *
 164  * \param size buffer size.
 165  * \param buffer buffer.
 166  *
 167  * \sa glSelectBuffer().
 168  *
 169  * \note this function can't be put in a display list.
 170  *
 171  * Verifies we're not in selection mode, flushes the vertices and initialize
 172  * the fields in __GLcontextRec::Select with the given buffer.
 173  */
 174 void GLAPIENTRY
 175 _mesa_SelectBuffer( GLsizei size, GLuint *buffer )
 176 {
 177    GET_CURRENT_CONTEXT(ctx);
 178    ASSERT_OUTSIDE_BEGIN_END(ctx);
 179
 180    if (ctx->RenderMode==GL_SELECT) {
 181       _mesa_error( ctx, GL_INVALID_OPERATION, "glSelectBuffer" );
 182       return;                   /* KW: added return */
 183    }
 184
 185    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 186    ctx->Select.Buffer = buffer;
 187    ctx->Select.BufferSize = size;
 188    ctx->Select.BufferCount = 0;
 189    ctx->Select.HitFlag = GL_FALSE;
 190    ctx->Select.HitMinZ = 1.0;
 191    ctx->Select.HitMaxZ = 0.0;
 192 }
 193
 194
 195 /**
 196  * Write a value of a record into the selection buffer.
 197  *
 198  * \param CTX GL context.
 199  * \param V value.
 200  *
 201  * Verifies there is free space in the buffer to write the value and
 202  * increments the pointer.
 203  */
 204 #define WRITE_RECORD( CTX, V )                                  \
 205         if (CTX->Select.BufferCount < CTX->Select.BufferSize) { \
 206            CTX->Select.Buffer[CTX->Select.BufferCount] = (V);   \
 207         }                                                       \
 208         CTX->Select.BufferCount++;
 209
 210
 211 /**
 212  * Update the hit flag and the maximum and minimum depth values.
 213  *
 214  * \param ctx GL context.
 215  * \param z depth.
 216  *
 217  * Sets gl_selection::HitFlag and updates gl_selection::HitMinZ and
 218  * gl_selection::HitMaxZ.
 219  */
 220 void _mesa_update_hitflag( GLcontext *ctx, GLfloat z )
 221 {
 222    ctx->Select.HitFlag = GL_TRUE;
 223    if (z < ctx->Select.HitMinZ) {
 224       ctx->Select.HitMinZ = z;
 225    }
 226    if (z > ctx->Select.HitMaxZ) {
 227       ctx->Select.HitMaxZ = z;
 228    }
 229 }
 230
 231
 232 /**
 233  * Write the hit record.
 234  *
 235  * \param ctx GL context.
 236  *
 237  * Write the hit record, i.e., the number of names in the stack, the minimum and
 238  * maximum depth values and the number of names in the name stack at the time
 239  * of the event. Resets the hit flag.
 240  *
 241  * \sa gl_selection.
 242  */
 243 static void write_hit_record( GLcontext *ctx )
 244 {
 245    GLuint i;
 246    GLuint zmin, zmax, zscale = (~0u);
 247
 248    /* HitMinZ and HitMaxZ are in [0,1].  Multiply these values by */
 249    /* 2^32-1 and round to nearest unsigned integer. */
 250
 251    assert( ctx != NULL ); /* this line magically fixes a SunOS 5.x/gcc bug */
 252    zmin = (GLuint) ((GLfloat) zscale * ctx->Select.HitMinZ);
 253    zmax = (GLuint) ((GLfloat) zscale * ctx->Select.HitMaxZ);
 254
 255    WRITE_RECORD( ctx, ctx->Select.NameStackDepth );
 256    WRITE_RECORD( ctx, zmin );
 257    WRITE_RECORD( ctx, zmax );
 258    for (i = 0; i < ctx->Select.NameStackDepth; i++) {
 259       WRITE_RECORD( ctx, ctx->Select.NameStack[i] );
 260    }
 261
 262    ctx->Select.Hits++;
 263    ctx->Select.HitFlag = GL_FALSE;
 264    ctx->Select.HitMinZ = 1.0;
 265    ctx->Select.HitMaxZ = -1.0;
 266 }
 267
 268
 269 /**
 270  * Initialize the name stack.
 271  *
 272  * Verifies we are in select mode and resets the name stack depth and resets
 273  * the hit record data in gl_selection. Marks new render mode in
 274  * __GLcontextRec::NewState.
 275  */
 276 void GLAPIENTRY
 277 _mesa_InitNames( void )
 278 {
 279    GET_CURRENT_CONTEXT(ctx);
 280    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 281
 282    /* Record the hit before the HitFlag is wiped out again. */
 283    if (ctx->RenderMode == GL_SELECT) {
 284       if (ctx->Select.HitFlag) {
 285          write_hit_record( ctx );
 286       }
 287    }
 288    ctx->Select.NameStackDepth = 0;
 289    ctx->Select.HitFlag = GL_FALSE;
 290    ctx->Select.HitMinZ = 1.0;
 291    ctx->Select.HitMaxZ = 0.0;
 292    ctx->NewState |= _NEW_RENDERMODE;
 293 }
 294
 295
 296 /**
 297  * Load the top-most name of the name stack.
 298  *
 299  * \param name name.
 300  *
 301  * Verifies we are in selection mode and that the name stack is not empty.
 302  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 303  * and replace the top-most name in the stack.
 304  *
 305  * sa __GLcontextRec::Select.
 306  */
 307 void GLAPIENTRY
 308 _mesa_LoadName( GLuint name )
 309 {
 310    GET_CURRENT_CONTEXT(ctx);
 311    ASSERT_OUTSIDE_BEGIN_END(ctx);
 312
 313    if (ctx->RenderMode != GL_SELECT) {
 314       return;
 315    }
 316    if (ctx->Select.NameStackDepth == 0) {
 317       _mesa_error( ctx, GL_INVALID_OPERATION, "glLoadName" );
 318       return;
 319    }
 320
 321    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 322
 323    if (ctx->Select.HitFlag) {
 324       write_hit_record( ctx );
 325    }
 326    if (ctx->Select.NameStackDepth < MAX_NAME_STACK_DEPTH) {
 327       ctx->Select.NameStack[ctx->Select.NameStackDepth-1] = name;
 328    }
 329    else {
 330       ctx->Select.NameStack[MAX_NAME_STACK_DEPTH-1] = name;
 331    }
 332 }
 333
 334
 335 /**
 336  * Push a name into the name stack.
 337  *
 338  * \param name name.
 339  *
 340  * Verifies we are in selection mode and that the name stack is not full.
 341  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 342  * and adds the name to the top of the name stack.
 343  *
 344  * sa __GLcontextRec::Select.
 345  */
 346 void GLAPIENTRY
 347 _mesa_PushName( GLuint name )
 348 {
 349    GET_CURRENT_CONTEXT(ctx);
 350    ASSERT_OUTSIDE_BEGIN_END(ctx);
 351
 352    if (ctx->RenderMode != GL_SELECT) {
 353       return;
 354    }
 355
 356    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 357    if (ctx->Select.HitFlag) {
 358       write_hit_record( ctx );
 359    }
 360    if (ctx->Select.NameStackDepth >= MAX_NAME_STACK_DEPTH) {
 361       _mesa_error( ctx, GL_STACK_OVERFLOW, "glPushName" );
 362    }
 363    else
 364       ctx->Select.NameStack[ctx->Select.NameStackDepth++] = name;
 365 }
 366
 367
 368 /**
 369  * Pop a name into the name stack.
 370  *
 371  * Verifies we are in selection mode and that the name stack is not empty.
 372  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 373  * and removes top-most name in the name stack.
 374  *
 375  * sa __GLcontextRec::Select.
 376  */
 377 void GLAPIENTRY
 378 _mesa_PopName( void )
 379 {
 380    GET_CURRENT_CONTEXT(ctx);
 381    ASSERT_OUTSIDE_BEGIN_END(ctx);
 382
 383    if (ctx->RenderMode != GL_SELECT) {
 384       return;
 385    }
 386
 387    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 388    if (ctx->Select.HitFlag) {
 389       write_hit_record( ctx );
 390    }
 391    if (ctx->Select.NameStackDepth == 0) {
 392       _mesa_error( ctx, GL_STACK_UNDERFLOW, "glPopName" );
 393    }
 394    else
 395       ctx->Select.NameStackDepth--;
 396 }
 397
 398 /*@}*/
 399
 400
 401 /**********************************************************************/
 402 /** \name Render Mode */
 403 /*@{*/
 404
 405 /**
 406  * Set rasterization mode.
 407  *
 408  * \param mode rasterization mode.
 409  *
 410  * \note this function can't be put in a display list.
 411  *
 412  * \sa glRenderMode().
 413  *
 414  * Flushes the vertices and do the necessary cleanup according to the previous
 415  * rasterization mode, such as writing the hit record or resent the select
 416  * buffer index when exiting the select mode. Updates
 417  * __GLcontextRec::RenderMode and notifies the driver via the
 418  * dd_function_table::RenderMode callback.
 419  */
 420 GLint GLAPIENTRY
 421 _mesa_RenderMode( GLenum mode )
 422 {
 423    GET_CURRENT_CONTEXT(ctx);
 424    GLint result;
 425    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, 0);
 426
 427    if (MESA_VERBOSE & VERBOSE_API)
 428       _mesa_debug(ctx, "glRenderMode %s\n", _mesa_lookup_enum_by_nr(mode));
 429
 430    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 431
 432    switch (ctx->RenderMode) {
 433       case GL_RENDER:
 434          result = 0;
 435          break;
 436       case GL_SELECT:
 437          if (ctx->Select.HitFlag) {
 438             write_hit_record( ctx );
 439          }
 440          if (ctx->Select.BufferCount > ctx->Select.BufferSize) {
 441             /* overflow */
 442 #ifdef DEBUG
 443             _mesa_warning(ctx, "Feedback buffer overflow");
 444 #endif
 445             result = -1;
 446          }
 447          else {
 448             result = ctx->Select.Hits;
 449          }
 450          ctx->Select.BufferCount = 0;
 451          ctx->Select.Hits = 0;
 452          ctx->Select.NameStackDepth = 0;
 453          break;
 454 #if _HAVE_FULL_GL
 455       case GL_FEEDBACK:
 456          if (ctx->Feedback.Count > ctx->Feedback.BufferSize) {
 457             /* overflow */
 458             result = -1;
 459          }
 460          else {
 461             result = ctx->Feedback.Count;
 462          }
 463          ctx->Feedback.Count = 0;
 464          break;
 465 #endif
 466       default:
 467          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 468          return 0;
 469    }
 470
 471    switch (mode) {
 472       case GL_RENDER:
 473          break;
 474       case GL_SELECT:
 475          if (ctx->Select.BufferSize==0) {
 476             /* haven't called glSelectBuffer yet */
 477             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 478          }
 479          break;
 480 #if _HAVE_FULL_GL
 481       case GL_FEEDBACK:
 482          if (ctx->Feedback.BufferSize==0) {
 483             /* haven't called glFeedbackBuffer yet */
 484             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 485          }
 486          break;
 487 #endif
 488       default:
 489          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 490          return 0;
 491    }
 492
 493    ctx->RenderMode = mode;
 494    if (ctx->Driver.RenderMode)
 495       ctx->Driver.RenderMode( ctx, mode );
 496
 497    return result;
 498 }
 499
 500 /*@}*/
 501
 502
 503 /**********************************************************************/
 504 /** \name Initialization */
 505 /*@{*/
 506
 507 /**
 508  * Initialize context feedback data.
 509  */
 510 void _mesa_init_feedback( GLcontext * ctx )
 511 {
 512    /* Feedback */
 513    ctx->Feedback.Type = GL_2D;   /* TODO: verify */
 514    ctx->Feedback.Buffer = NULL;
 515    ctx->Feedback.BufferSize = 0;
 516    ctx->Feedback.Count = 0;
 517
 518    /* Selection/picking */
 519    ctx->Select.Buffer = NULL;
 520    ctx->Select.BufferSize = 0;
 521    ctx->Select.BufferCount = 0;
 522    ctx->Select.Hits = 0;
 523    ctx->Select.NameStackDepth = 0;
 524
 525    /* Miscellaneous */
 526    ctx->RenderMode = GL_RENDER;
 527 }
 528
 529 /*@}*/