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