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  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  22  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  23  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24  * OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27 /**
  28  * \file feedback.c
  29  * Selection and feedback modes functions.
  30  */
  31
  32
  33 #include "glheader.h"
  34 #include "colormac.h"
  35 #include "context.h"
  36 #include "enums.h"
  37 #include "feedback.h"
  38 #include "macros.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 void GLAPIENTRY
  51 _mesa_FeedbackBuffer( GLsizei size, GLenum type, GLfloat *buffer )
  52 {
  53    GET_CURRENT_CONTEXT(ctx);
  54
  55    if (ctx->RenderMode==GL_FEEDBACK) {
  56       _mesa_error( ctx, GL_INVALID_OPERATION, "glFeedbackBuffer" );
  57       return;
  58    }
  59    if (size<0) {
  60       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(size<0)" );
  61       return;
  62    }
  63    if (!buffer && size > 0) {
  64       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(buffer==NULL)" );
  65       ctx->Feedback.BufferSize = 0;
  66       return;
  67    }
  68
  69    switch (type) {
  70       case GL_2D:
  71          ctx->Feedback._Mask = 0;
  72          break;
  73       case GL_3D:
  74          ctx->Feedback._Mask = FB_3D;
  75          break;
  76       case GL_3D_COLOR:
  77          ctx->Feedback._Mask = (FB_3D | FB_COLOR);
  78          break;
  79       case GL_3D_COLOR_TEXTURE:
  80          ctx->Feedback._Mask = (FB_3D | FB_COLOR | FB_TEXTURE);
  81          break;
  82       case GL_4D_COLOR_TEXTURE:
  83          ctx->Feedback._Mask = (FB_3D | FB_4D | FB_COLOR | FB_TEXTURE);
  84          break;
  85       default:
  86          _mesa_error( ctx, GL_INVALID_ENUM, "glFeedbackBuffer" );
  87          return;
  88    }
  89
  90    FLUSH_VERTICES(ctx, _NEW_RENDERMODE); /* Always flush */
  91    ctx->Feedback.Type = type;
  92    ctx->Feedback.BufferSize = size;
  93    ctx->Feedback.Buffer = buffer;
  94    ctx->Feedback.Count = 0;                   /* Becaues of this. */
  95 }
  96
  97
  98 void GLAPIENTRY
  99 _mesa_PassThrough( GLfloat token )
 100 {
 101    GET_CURRENT_CONTEXT(ctx);
 102
 103    if (ctx->RenderMode==GL_FEEDBACK) {
 104       FLUSH_VERTICES(ctx, 0);
 105       _mesa_feedback_token( ctx, (GLfloat) (GLint) GL_PASS_THROUGH_TOKEN );
 106       _mesa_feedback_token( ctx, token );
 107    }
 108 }
 109
 110
 111 /**
 112  * Put a vertex into the feedback buffer.
 113  */
 114 void
 115 _mesa_feedback_vertex(struct gl_context *ctx,
 116                       const GLfloat win[4],
 117                       const GLfloat color[4],
 118                       const GLfloat texcoord[4])
 119 {
 120    _mesa_feedback_token( ctx, win[0] );
 121    _mesa_feedback_token( ctx, win[1] );
 122    if (ctx->Feedback._Mask & FB_3D) {
 123       _mesa_feedback_token( ctx, win[2] );
 124    }
 125    if (ctx->Feedback._Mask & FB_4D) {
 126       _mesa_feedback_token( ctx, win[3] );
 127    }
 128    if (ctx->Feedback._Mask & FB_COLOR) {
 129       _mesa_feedback_token( ctx, color[0] );
 130       _mesa_feedback_token( ctx, color[1] );
 131       _mesa_feedback_token( ctx, color[2] );
 132       _mesa_feedback_token( ctx, color[3] );
 133    }
 134    if (ctx->Feedback._Mask & FB_TEXTURE) {
 135       _mesa_feedback_token( ctx, texcoord[0] );
 136       _mesa_feedback_token( ctx, texcoord[1] );
 137       _mesa_feedback_token( ctx, texcoord[2] );
 138       _mesa_feedback_token( ctx, texcoord[3] );
 139    }
 140 }
 141
 142
 143 /**********************************************************************/
 144 /** \name Selection */
 145 /*@{*/
 146
 147 /**
 148  * Establish a buffer for selection mode values.
 149  *
 150  * \param size buffer size.
 151  * \param buffer buffer.
 152  *
 153  * \sa glSelectBuffer().
 154  *
 155  * \note this function can't be put in a display list.
 156  *
 157  * Verifies we're not in selection mode, flushes the vertices and initialize
 158  * the fields in __struct gl_contextRec::Select with the given buffer.
 159  */
 160 void GLAPIENTRY
 161 _mesa_SelectBuffer( GLsizei size, GLuint *buffer )
 162 {
 163    GET_CURRENT_CONTEXT(ctx);
 164
 165    if (size < 0) {
 166       _mesa_error(ctx, GL_INVALID_VALUE, "glSelectBuffer(size)");
 167       return;
 168    }
 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(struct gl_context *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(struct gl_context *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(struct gl_context *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  * __struct gl_contextRec::NewState.
 270  */
 271 void GLAPIENTRY
 272 _mesa_InitNames( void )
 273 {
 274    GET_CURRENT_CONTEXT(ctx);
 275    FLUSH_VERTICES(ctx, 0);
 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 __struct gl_contextRec::Select.
 301  */
 302 void GLAPIENTRY
 303 _mesa_LoadName( GLuint name )
 304 {
 305    GET_CURRENT_CONTEXT(ctx);
 306
 307    if (ctx->RenderMode != GL_SELECT) {
 308       return;
 309    }
 310    if (ctx->Select.NameStackDepth == 0) {
 311       _mesa_error( ctx, GL_INVALID_OPERATION, "glLoadName" );
 312       return;
 313    }
 314
 315    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 316
 317    if (ctx->Select.HitFlag) {
 318       write_hit_record( ctx );
 319    }
 320    if (ctx->Select.NameStackDepth < MAX_NAME_STACK_DEPTH) {
 321       ctx->Select.NameStack[ctx->Select.NameStackDepth-1] = name;
 322    }
 323    else {
 324       ctx->Select.NameStack[MAX_NAME_STACK_DEPTH-1] = name;
 325    }
 326 }
 327
 328
 329 /**
 330  * Push a name into the name stack.
 331  *
 332  * \param name name.
 333  *
 334  * Verifies we are in selection mode and that the name stack is not full.
 335  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 336  * and adds the name to the top of the name stack.
 337  *
 338  * sa __struct gl_contextRec::Select.
 339  */
 340 void GLAPIENTRY
 341 _mesa_PushName( GLuint name )
 342 {
 343    GET_CURRENT_CONTEXT(ctx);
 344
 345    if (ctx->RenderMode != GL_SELECT) {
 346       return;
 347    }
 348
 349    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 350    if (ctx->Select.HitFlag) {
 351       write_hit_record( ctx );
 352    }
 353    if (ctx->Select.NameStackDepth >= MAX_NAME_STACK_DEPTH) {
 354       _mesa_error( ctx, GL_STACK_OVERFLOW, "glPushName" );
 355    }
 356    else
 357       ctx->Select.NameStack[ctx->Select.NameStackDepth++] = name;
 358 }
 359
 360
 361 /**
 362  * Pop a name into the name stack.
 363  *
 364  * Verifies we are in selection mode and that the name stack is not empty.
 365  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 366  * and removes top-most name in the name stack.
 367  *
 368  * sa __struct gl_contextRec::Select.
 369  */
 370 void GLAPIENTRY
 371 _mesa_PopName( void )
 372 {
 373    GET_CURRENT_CONTEXT(ctx);
 374
 375    if (ctx->RenderMode != GL_SELECT) {
 376       return;
 377    }
 378
 379    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 380    if (ctx->Select.HitFlag) {
 381       write_hit_record( ctx );
 382    }
 383    if (ctx->Select.NameStackDepth == 0) {
 384       _mesa_error( ctx, GL_STACK_UNDERFLOW, "glPopName" );
 385    }
 386    else
 387       ctx->Select.NameStackDepth--;
 388 }
 389
 390 /*@}*/
 391
 392
 393 /**********************************************************************/
 394 /** \name Render Mode */
 395 /*@{*/
 396
 397 /**
 398  * Set rasterization mode.
 399  *
 400  * \param mode rasterization mode.
 401  *
 402  * \note this function can't be put in a display list.
 403  *
 404  * \sa glRenderMode().
 405  *
 406  * Flushes the vertices and do the necessary cleanup according to the previous
 407  * rasterization mode, such as writing the hit record or resent the select
 408  * buffer index when exiting the select mode. Updates
 409  * __struct gl_contextRec::RenderMode and notifies the driver via the
 410  * dd_function_table::RenderMode callback.
 411  */
 412 GLint GLAPIENTRY
 413 _mesa_RenderMode( GLenum mode )
 414 {
 415    GET_CURRENT_CONTEXT(ctx);
 416    GLint result;
 417    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, 0);
 418
 419    if (MESA_VERBOSE & VERBOSE_API)
 420       _mesa_debug(ctx, "glRenderMode %s\n", _mesa_lookup_enum_by_nr(mode));
 421
 422    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 423
 424    switch (ctx->RenderMode) {
 425       case GL_RENDER:
 426          result = 0;
 427          break;
 428       case GL_SELECT:
 429          if (ctx->Select.HitFlag) {
 430             write_hit_record( ctx );
 431          }
 432          if (ctx->Select.BufferCount > ctx->Select.BufferSize) {
 433             /* overflow */
 434 #ifdef DEBUG
 435             _mesa_warning(ctx, "Feedback buffer overflow");
 436 #endif
 437             result = -1;
 438          }
 439          else {
 440             result = ctx->Select.Hits;
 441          }
 442          ctx->Select.BufferCount = 0;
 443          ctx->Select.Hits = 0;
 444          ctx->Select.NameStackDepth = 0;
 445          break;
 446       case GL_FEEDBACK:
 447          if (ctx->Feedback.Count > ctx->Feedback.BufferSize) {
 448             /* overflow */
 449             result = -1;
 450          }
 451          else {
 452             result = ctx->Feedback.Count;
 453          }
 454          ctx->Feedback.Count = 0;
 455          break;
 456       default:
 457          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 458          return 0;
 459    }
 460
 461    switch (mode) {
 462       case GL_RENDER:
 463          break;
 464       case GL_SELECT:
 465          if (ctx->Select.BufferSize==0) {
 466             /* haven't called glSelectBuffer yet */
 467             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 468          }
 469          break;
 470       case GL_FEEDBACK:
 471          if (ctx->Feedback.BufferSize==0) {
 472             /* haven't called glFeedbackBuffer yet */
 473             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 474          }
 475          break;
 476       default:
 477          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 478          return 0;
 479    }
 480
 481    ctx->RenderMode = mode;
 482    if (ctx->Driver.RenderMode)
 483       ctx->Driver.RenderMode( ctx, mode );
 484
 485    return result;
 486 }
 487
 488 /*@}*/
 489
 490
 491 /**********************************************************************/
 492 /** \name Initialization */
 493 /*@{*/
 494
 495 /**
 496  * Initialize context feedback data.
 497  */
 498 void _mesa_init_feedback( struct gl_context * ctx )
 499 {
 500    /* Feedback */
 501    ctx->Feedback.Type = GL_2D;   /* TODO: verify */
 502    ctx->Feedback.Buffer = NULL;
 503    ctx->Feedback.BufferSize = 0;
 504    ctx->Feedback.Count = 0;
 505
 506    /* Selection/picking */
 507    ctx->Select.Buffer = NULL;
 508    ctx->Select.BufferSize = 0;
 509    ctx->Select.BufferCount = 0;
 510    ctx->Select.Hits = 0;
 511    ctx->Select.NameStackDepth = 0;
 512
 513    /* Miscellaneous */
 514    ctx->RenderMode = GL_RENDER;
 515 }
 516
 517 /*@}*/