src/mesa/main/feedback.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.5
   4  *
   5  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   6  * Copyright (C) 2009  VMware, Inc.  All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR 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 "colormac.h"
  34 #include "context.h"
  35 #include "enums.h"
  36 #include "feedback.h"
  37 #include "macros.h"
  38 #include "mtypes.h"
  39 #include "main/dispatch.h"
  40
  41
  42 #if FEATURE_feedback
  43
  44
  45 #define FB_3D           0x01
  46 #define FB_4D           0x02
  47 #define FB_COLOR        0x04
  48 #define FB_TEXTURE      0X08
  49
  50
  51
  52 static void GLAPIENTRY
  53 _mesa_FeedbackBuffer( GLsizei size, GLenum type, GLfloat *buffer )
  54 {
  55    GET_CURRENT_CONTEXT(ctx);
  56    ASSERT_OUTSIDE_BEGIN_END(ctx);
  57
  58    if (ctx->RenderMode==GL_FEEDBACK) {
  59       _mesa_error( ctx, GL_INVALID_OPERATION, "glFeedbackBuffer" );
  60       return;
  61    }
  62    if (size<0) {
  63       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(size<0)" );
  64       return;
  65    }
  66    if (!buffer) {
  67       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(buffer==NULL)" );
  68       ctx->Feedback.BufferSize = 0;
  69       return;
  70    }
  71
  72    switch (type) {
  73       case GL_2D:
  74          ctx->Feedback._Mask = 0;
  75          break;
  76       case GL_3D:
  77          ctx->Feedback._Mask = FB_3D;
  78          break;
  79       case GL_3D_COLOR:
  80          ctx->Feedback._Mask = (FB_3D | FB_COLOR);
  81          break;
  82       case GL_3D_COLOR_TEXTURE:
  83          ctx->Feedback._Mask = (FB_3D | FB_COLOR | FB_TEXTURE);
  84          break;
  85       case GL_4D_COLOR_TEXTURE:
  86          ctx->Feedback._Mask = (FB_3D | FB_4D | FB_COLOR | FB_TEXTURE);
  87          break;
  88       default:
  89          _mesa_error( ctx, GL_INVALID_ENUM, "glFeedbackBuffer" );
  90          return;
  91    }
  92
  93    FLUSH_VERTICES(ctx, _NEW_RENDERMODE); /* Always flush */
  94    ctx->Feedback.Type = type;
  95    ctx->Feedback.BufferSize = size;
  96    ctx->Feedback.Buffer = buffer;
  97    ctx->Feedback.Count = 0;                   /* Becaues of this. */
  98 }
  99
 100
 101 static void GLAPIENTRY
 102 _mesa_PassThrough( GLfloat token )
 103 {
 104    GET_CURRENT_CONTEXT(ctx);
 105    ASSERT_OUTSIDE_BEGIN_END(ctx);
 106
 107    if (ctx->RenderMode==GL_FEEDBACK) {
 108       FLUSH_VERTICES(ctx, 0);
 109       _mesa_feedback_token( ctx, (GLfloat) (GLint) GL_PASS_THROUGH_TOKEN );
 110       _mesa_feedback_token( ctx, token );
 111    }
 112 }
 113
 114
 115 /**
 116  * Put a vertex into the feedback buffer.
 117  */
 118 void
 119 _mesa_feedback_vertex(GLcontext *ctx,
 120                       const GLfloat win[4],
 121                       const GLfloat color[4],
 122                       const GLfloat texcoord[4])
 123 {
 124    _mesa_feedback_token( ctx, win[0] );
 125    _mesa_feedback_token( ctx, win[1] );
 126    if (ctx->Feedback._Mask & FB_3D) {
 127       _mesa_feedback_token( ctx, win[2] );
 128    }
 129    if (ctx->Feedback._Mask & FB_4D) {
 130       _mesa_feedback_token( ctx, win[3] );
 131    }
 132    if (ctx->Feedback._Mask & FB_COLOR) {
 133       _mesa_feedback_token( ctx, color[0] );
 134       _mesa_feedback_token( ctx, color[1] );
 135       _mesa_feedback_token( ctx, color[2] );
 136       _mesa_feedback_token( ctx, color[3] );
 137    }
 138    if (ctx->Feedback._Mask & FB_TEXTURE) {
 139       _mesa_feedback_token( ctx, texcoord[0] );
 140       _mesa_feedback_token( ctx, texcoord[1] );
 141       _mesa_feedback_token( ctx, texcoord[2] );
 142       _mesa_feedback_token( ctx, texcoord[3] );
 143    }
 144 }
 145
 146
 147 /**********************************************************************/
 148 /** \name Selection */
 149 /*@{*/
 150
 151 /**
 152  * Establish a buffer for selection mode values.
 153  *
 154  * \param size buffer size.
 155  * \param buffer buffer.
 156  *
 157  * \sa glSelectBuffer().
 158  *
 159  * \note this function can't be put in a display list.
 160  *
 161  * Verifies we're not in selection mode, flushes the vertices and initialize
 162  * the fields in __GLcontextRec::Select with the given buffer.
 163  */
 164 static void GLAPIENTRY
 165 _mesa_SelectBuffer( GLsizei size, GLuint *buffer )
 166 {
 167    GET_CURRENT_CONTEXT(ctx);
 168    ASSERT_OUTSIDE_BEGIN_END(ctx);
 169
 170    if (ctx->RenderMode==GL_SELECT) {
 171       _mesa_error( ctx, GL_INVALID_OPERATION, "glSelectBuffer" );
 172       return;                   /* KW: added return */
 173    }
 174
 175    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 176    ctx->Select.Buffer = buffer;
 177    ctx->Select.BufferSize = size;
 178    ctx->Select.BufferCount = 0;
 179    ctx->Select.HitFlag = GL_FALSE;
 180    ctx->Select.HitMinZ = 1.0;
 181    ctx->Select.HitMaxZ = 0.0;
 182 }
 183
 184
 185 /**
 186  * Write a value of a record into the selection buffer.
 187  *
 188  * \param ctx GL context.
 189  * \param value value.
 190  *
 191  * Verifies there is free space in the buffer to write the value and
 192  * increments the pointer.
 193  */
 194 static INLINE void
 195 write_record(GLcontext *ctx, GLuint value)
 196 {
 197    if (ctx->Select.BufferCount < ctx->Select.BufferSize) {
 198       ctx->Select.Buffer[ctx->Select.BufferCount] = value;
 199    }
 200    ctx->Select.BufferCount++;
 201 }
 202
 203
 204 /**
 205  * Update the hit flag and the maximum and minimum depth values.
 206  *
 207  * \param ctx GL context.
 208  * \param z depth.
 209  *
 210  * Sets gl_selection::HitFlag and updates gl_selection::HitMinZ and
 211  * gl_selection::HitMaxZ.
 212  */
 213 void
 214 _mesa_update_hitflag(GLcontext *ctx, GLfloat z)
 215 {
 216    ctx->Select.HitFlag = GL_TRUE;
 217    if (z < ctx->Select.HitMinZ) {
 218       ctx->Select.HitMinZ = z;
 219    }
 220    if (z > ctx->Select.HitMaxZ) {
 221       ctx->Select.HitMaxZ = z;
 222    }
 223 }
 224
 225
 226 /**
 227  * Write the hit record.
 228  *
 229  * \param ctx GL context.
 230  *
 231  * Write the hit record, i.e., the number of names in the stack, the minimum and
 232  * maximum depth values and the number of names in the name stack at the time
 233  * of the event. Resets the hit flag.
 234  *
 235  * \sa gl_selection.
 236  */
 237 static void
 238 write_hit_record(GLcontext *ctx)
 239 {
 240    GLuint i;
 241    GLuint zmin, zmax, zscale = (~0u);
 242
 243    /* HitMinZ and HitMaxZ are in [0,1].  Multiply these values by */
 244    /* 2^32-1 and round to nearest unsigned integer. */
 245
 246    assert( ctx != NULL ); /* this line magically fixes a SunOS 5.x/gcc bug */
 247    zmin = (GLuint) ((GLfloat) zscale * ctx->Select.HitMinZ);
 248    zmax = (GLuint) ((GLfloat) zscale * ctx->Select.HitMaxZ);
 249
 250    write_record( ctx, ctx->Select.NameStackDepth );
 251    write_record( ctx, zmin );
 252    write_record( ctx, zmax );
 253    for (i = 0; i < ctx->Select.NameStackDepth; i++) {
 254       write_record( ctx, ctx->Select.NameStack[i] );
 255    }
 256
 257    ctx->Select.Hits++;
 258    ctx->Select.HitFlag = GL_FALSE;
 259    ctx->Select.HitMinZ = 1.0;
 260    ctx->Select.HitMaxZ = -1.0;
 261 }
 262
 263
 264 /**
 265  * Initialize the name stack.
 266  *
 267  * Verifies we are in select mode and resets the name stack depth and resets
 268  * the hit record data in gl_selection. Marks new render mode in
 269  * __GLcontextRec::NewState.
 270  */
 271 static void GLAPIENTRY
 272 _mesa_InitNames( void )
 273 {
 274    GET_CURRENT_CONTEXT(ctx);
 275    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 276
 277    /* Record the hit before the HitFlag is wiped out again. */
 278    if (ctx->RenderMode == GL_SELECT) {
 279       if (ctx->Select.HitFlag) {
 280          write_hit_record( ctx );
 281       }
 282    }
 283    ctx->Select.NameStackDepth = 0;
 284    ctx->Select.HitFlag = GL_FALSE;
 285    ctx->Select.HitMinZ = 1.0;
 286    ctx->Select.HitMaxZ = 0.0;
 287    ctx->NewState |= _NEW_RENDERMODE;
 288 }
 289
 290
 291 /**
 292  * Load the top-most name of the name stack.
 293  *
 294  * \param name name.
 295  *
 296  * Verifies we are in selection mode and that the name stack is not empty.
 297  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 298  * and replace the top-most name in the stack.
 299  *
 300  * sa __GLcontextRec::Select.
 301  */
 302 static void GLAPIENTRY
 303 _mesa_LoadName( GLuint name )
 304 {
 305    GET_CURRENT_CONTEXT(ctx);
 306    ASSERT_OUTSIDE_BEGIN_END(ctx);
 307
 308    if (ctx->RenderMode != GL_SELECT) {
 309       return;
 310    }
 311    if (ctx->Select.NameStackDepth == 0) {
 312       _mesa_error( ctx, GL_INVALID_OPERATION, "glLoadName" );
 313       return;
 314    }
 315
 316    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 317
 318    if (ctx->Select.HitFlag) {
 319       write_hit_record( ctx );
 320    }
 321    if (ctx->Select.NameStackDepth < MAX_NAME_STACK_DEPTH) {
 322       ctx->Select.NameStack[ctx->Select.NameStackDepth-1] = name;
 323    }
 324    else {
 325       ctx->Select.NameStack[MAX_NAME_STACK_DEPTH-1] = name;
 326    }
 327 }
 328
 329
 330 /**
 331  * Push a name into the name stack.
 332  *
 333  * \param name name.
 334  *
 335  * Verifies we are in selection mode and that the name stack is not full.
 336  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 337  * and adds the name to the top of the name stack.
 338  *
 339  * sa __GLcontextRec::Select.
 340  */
 341 static void GLAPIENTRY
 342 _mesa_PushName( GLuint name )
 343 {
 344    GET_CURRENT_CONTEXT(ctx);
 345    ASSERT_OUTSIDE_BEGIN_END(ctx);
 346
 347    if (ctx->RenderMode != GL_SELECT) {
 348       return;
 349    }
 350
 351    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 352    if (ctx->Select.HitFlag) {
 353       write_hit_record( ctx );
 354    }
 355    if (ctx->Select.NameStackDepth >= MAX_NAME_STACK_DEPTH) {
 356       _mesa_error( ctx, GL_STACK_OVERFLOW, "glPushName" );
 357    }
 358    else
 359       ctx->Select.NameStack[ctx->Select.NameStackDepth++] = name;
 360 }
 361
 362
 363 /**
 364  * Pop a name into the name stack.
 365  *
 366  * Verifies we are in selection mode and that the name stack is not empty.
 367  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 368  * and removes top-most name in the name stack.
 369  *
 370  * sa __GLcontextRec::Select.
 371  */
 372 static void GLAPIENTRY
 373 _mesa_PopName( void )
 374 {
 375    GET_CURRENT_CONTEXT(ctx);
 376    ASSERT_OUTSIDE_BEGIN_END(ctx);
 377
 378    if (ctx->RenderMode != GL_SELECT) {
 379       return;
 380    }
 381
 382    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 383    if (ctx->Select.HitFlag) {
 384       write_hit_record( ctx );
 385    }
 386    if (ctx->Select.NameStackDepth == 0) {
 387       _mesa_error( ctx, GL_STACK_UNDERFLOW, "glPopName" );
 388    }
 389    else
 390       ctx->Select.NameStackDepth--;
 391 }
 392
 393 /*@}*/
 394
 395
 396 /**********************************************************************/
 397 /** \name Render Mode */
 398 /*@{*/
 399
 400 /**
 401  * Set rasterization mode.
 402  *
 403  * \param mode rasterization mode.
 404  *
 405  * \note this function can't be put in a display list.
 406  *
 407  * \sa glRenderMode().
 408  *
 409  * Flushes the vertices and do the necessary cleanup according to the previous
 410  * rasterization mode, such as writing the hit record or resent the select
 411  * buffer index when exiting the select mode. Updates
 412  * __GLcontextRec::RenderMode and notifies the driver via the
 413  * dd_function_table::RenderMode callback.
 414  */
 415 static GLint GLAPIENTRY
 416 _mesa_RenderMode( GLenum mode )
 417 {
 418    GET_CURRENT_CONTEXT(ctx);
 419    GLint result;
 420    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, 0);
 421
 422    if (MESA_VERBOSE & VERBOSE_API)
 423       _mesa_debug(ctx, "glRenderMode %s\n", _mesa_lookup_enum_by_nr(mode));
 424
 425    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 426
 427    switch (ctx->RenderMode) {
 428       case GL_RENDER:
 429          result = 0;
 430          break;
 431       case GL_SELECT:
 432          if (ctx->Select.HitFlag) {
 433             write_hit_record( ctx );
 434          }
 435          if (ctx->Select.BufferCount > ctx->Select.BufferSize) {
 436             /* overflow */
 437 #ifdef DEBUG
 438             _mesa_warning(ctx, "Feedback buffer overflow");
 439 #endif
 440             result = -1;
 441          }
 442          else {
 443             result = ctx->Select.Hits;
 444          }
 445          ctx->Select.BufferCount = 0;
 446          ctx->Select.Hits = 0;
 447          ctx->Select.NameStackDepth = 0;
 448          break;
 449 #if _HAVE_FULL_GL
 450       case GL_FEEDBACK:
 451          if (ctx->Feedback.Count > ctx->Feedback.BufferSize) {
 452             /* overflow */
 453             result = -1;
 454          }
 455          else {
 456             result = ctx->Feedback.Count;
 457          }
 458          ctx->Feedback.Count = 0;
 459          break;
 460 #endif
 461       default:
 462          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 463          return 0;
 464    }
 465
 466    switch (mode) {
 467       case GL_RENDER:
 468          break;
 469       case GL_SELECT:
 470          if (ctx->Select.BufferSize==0) {
 471             /* haven't called glSelectBuffer yet */
 472             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 473          }
 474          break;
 475 #if _HAVE_FULL_GL
 476       case GL_FEEDBACK:
 477          if (ctx->Feedback.BufferSize==0) {
 478             /* haven't called glFeedbackBuffer yet */
 479             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 480          }
 481          break;
 482 #endif
 483       default:
 484          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 485          return 0;
 486    }
 487
 488    ctx->RenderMode = mode;
 489    if (ctx->Driver.RenderMode)
 490       ctx->Driver.RenderMode( ctx, mode );
 491
 492    return result;
 493 }
 494
 495 /*@}*/
 496
 497
 498 void
 499 _mesa_init_feedback_dispatch(struct _glapi_table *disp)
 500 {
 501    SET_InitNames(disp, _mesa_InitNames);
 502    SET_FeedbackBuffer(disp, _mesa_FeedbackBuffer);
 503    SET_LoadName(disp, _mesa_LoadName);
 504    SET_PassThrough(disp, _mesa_PassThrough);
 505    SET_PopName(disp, _mesa_PopName);
 506    SET_PushName(disp, _mesa_PushName);
 507    SET_SelectBuffer(disp, _mesa_SelectBuffer);
 508    SET_RenderMode(disp, _mesa_RenderMode);
 509 }
 510
 511
 512 #endif /* FEATURE_feedback */
 513
 514
 515 /**********************************************************************/
 516 /** \name Initialization */
 517 /*@{*/
 518
 519 /**
 520  * Initialize context feedback data.
 521  */
 522 void _mesa_init_feedback( GLcontext * ctx )
 523 {
 524    /* Feedback */
 525    ctx->Feedback.Type = GL_2D;   /* TODO: verify */
 526    ctx->Feedback.Buffer = NULL;
 527    ctx->Feedback.BufferSize = 0;
 528    ctx->Feedback.Count = 0;
 529
 530    /* Selection/picking */
 531    ctx->Select.Buffer = NULL;
 532    ctx->Select.BufferSize = 0;
 533    ctx->Select.BufferCount = 0;
 534    ctx->Select.Hits = 0;
 535    ctx->Select.NameStackDepth = 0;
 536
 537    /* Miscellaneous */
 538    ctx->RenderMode = GL_RENDER;
 539 }
 540
 541 /*@}*/