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 #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
  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
  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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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_lookup_enum_by_nr(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  */
 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 /*@}*/