src/mesa/main/feedback.c

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