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 "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 #define FB_3D           0x01
  43 #define FB_4D           0x02
  44 #define FB_COLOR        0x04
  45 #define FB_TEXTURE      0X08
  46
  47
  48
  49 void GLAPIENTRY
  50 _mesa_FeedbackBuffer( GLsizei size, GLenum type, GLfloat *buffer )
  51 {
  52    GET_CURRENT_CONTEXT(ctx);
  53
  54    if (ctx->RenderMode==GL_FEEDBACK) {
  55       _mesa_error( ctx, GL_INVALID_OPERATION, "glFeedbackBuffer" );
  56       return;
  57    }
  58    if (size<0) {
  59       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(size<0)" );
  60       return;
  61    }
  62    if (!buffer && size > 0) {
  63       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(buffer==NULL)" );
  64       ctx->Feedback.BufferSize = 0;
  65       return;
  66    }
  67
  68    switch (type) {
  69       case GL_2D:
  70          ctx->Feedback._Mask = 0;
  71          break;
  72       case GL_3D:
  73          ctx->Feedback._Mask = FB_3D;
  74          break;
  75       case GL_3D_COLOR:
  76          ctx->Feedback._Mask = (FB_3D | FB_COLOR);
  77          break;
  78       case GL_3D_COLOR_TEXTURE:
  79          ctx->Feedback._Mask = (FB_3D | FB_COLOR | FB_TEXTURE);
  80          break;
  81       case GL_4D_COLOR_TEXTURE:
  82          ctx->Feedback._Mask = (FB_3D | FB_4D | FB_COLOR | FB_TEXTURE);
  83          break;
  84       default:
  85          _mesa_error( ctx, GL_INVALID_ENUM, "glFeedbackBuffer" );
  86          return;
  87    }
  88
  89    FLUSH_VERTICES(ctx, _NEW_RENDERMODE); /* Always flush */
  90    ctx->Feedback.Type = type;
  91    ctx->Feedback.BufferSize = size;
  92    ctx->Feedback.Buffer = buffer;
  93    ctx->Feedback.Count = 0;                   /* Becaues of this. */
  94 }
  95
  96
  97 void GLAPIENTRY
  98 _mesa_PassThrough( GLfloat token )
  99 {
 100    GET_CURRENT_CONTEXT(ctx);
 101
 102    if (ctx->RenderMode==GL_FEEDBACK) {
 103       FLUSH_VERTICES(ctx, 0);
 104       _mesa_feedback_token( ctx, (GLfloat) (GLint) GL_PASS_THROUGH_TOKEN );
 105       _mesa_feedback_token( ctx, token );
 106    }
 107 }
 108
 109
 110 /**
 111  * Put a vertex into the feedback buffer.
 112  */
 113 void
 114 _mesa_feedback_vertex(struct gl_context *ctx,
 115                       const GLfloat win[4],
 116                       const GLfloat color[4],
 117                       const GLfloat texcoord[4])
 118 {
 119    _mesa_feedback_token( ctx, win[0] );
 120    _mesa_feedback_token( ctx, win[1] );
 121    if (ctx->Feedback._Mask & FB_3D) {
 122       _mesa_feedback_token( ctx, win[2] );
 123    }
 124    if (ctx->Feedback._Mask & FB_4D) {
 125       _mesa_feedback_token( ctx, win[3] );
 126    }
 127    if (ctx->Feedback._Mask & FB_COLOR) {
 128       _mesa_feedback_token( ctx, color[0] );
 129       _mesa_feedback_token( ctx, color[1] );
 130       _mesa_feedback_token( ctx, color[2] );
 131       _mesa_feedback_token( ctx, color[3] );
 132    }
 133    if (ctx->Feedback._Mask & FB_TEXTURE) {
 134       _mesa_feedback_token( ctx, texcoord[0] );
 135       _mesa_feedback_token( ctx, texcoord[1] );
 136       _mesa_feedback_token( ctx, texcoord[2] );
 137       _mesa_feedback_token( ctx, texcoord[3] );
 138    }
 139 }
 140
 141
 142 /**********************************************************************/
 143 /** \name Selection */
 144 /*@{*/
 145
 146 /**
 147  * Establish a buffer for selection mode values.
 148  *
 149  * \param size buffer size.
 150  * \param buffer buffer.
 151  *
 152  * \sa glSelectBuffer().
 153  *
 154  * \note this function can't be put in a display list.
 155  *
 156  * Verifies we're not in selection mode, flushes the vertices and initialize
 157  * the fields in __struct gl_contextRec::Select with the given buffer.
 158  */
 159 void GLAPIENTRY
 160 _mesa_SelectBuffer( GLsizei size, GLuint *buffer )
 161 {
 162    GET_CURRENT_CONTEXT(ctx);
 163
 164    if (size < 0) {
 165       _mesa_error(ctx, GL_INVALID_VALUE, "glSelectBuffer(size)");
 166       return;
 167    }
 168
 169    if (ctx->RenderMode==GL_SELECT) {
 170       _mesa_error( ctx, GL_INVALID_OPERATION, "glSelectBuffer" );
 171       return;                   /* KW: added return */
 172    }
 173
 174    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 175    ctx->Select.Buffer = buffer;
 176    ctx->Select.BufferSize = size;
 177    ctx->Select.BufferCount = 0;
 178    ctx->Select.HitFlag = GL_FALSE;
 179    ctx->Select.HitMinZ = 1.0;
 180    ctx->Select.HitMaxZ = 0.0;
 181 }
 182
 183
 184 /**
 185  * Write a value of a record into the selection buffer.
 186  *
 187  * \param ctx GL context.
 188  * \param value value.
 189  *
 190  * Verifies there is free space in the buffer to write the value and
 191  * increments the pointer.
 192  */
 193 static inline void
 194 write_record(struct gl_context *ctx, GLuint value)
 195 {
 196    if (ctx->Select.BufferCount < ctx->Select.BufferSize) {
 197       ctx->Select.Buffer[ctx->Select.BufferCount] = value;
 198    }
 199    ctx->Select.BufferCount++;
 200 }
 201
 202
 203 /**
 204  * Update the hit flag and the maximum and minimum depth values.
 205  *
 206  * \param ctx GL context.
 207  * \param z depth.
 208  *
 209  * Sets gl_selection::HitFlag and updates gl_selection::HitMinZ and
 210  * gl_selection::HitMaxZ.
 211  */
 212 void
 213 _mesa_update_hitflag(struct gl_context *ctx, GLfloat z)
 214 {
 215    ctx->Select.HitFlag = GL_TRUE;
 216    if (z < ctx->Select.HitMinZ) {
 217       ctx->Select.HitMinZ = z;
 218    }
 219    if (z > ctx->Select.HitMaxZ) {
 220       ctx->Select.HitMaxZ = z;
 221    }
 222 }
 223
 224
 225 /**
 226  * Write the hit record.
 227  *
 228  * \param ctx GL context.
 229  *
 230  * Write the hit record, i.e., the number of names in the stack, the minimum and
 231  * maximum depth values and the number of names in the name stack at the time
 232  * of the event. Resets the hit flag.
 233  *
 234  * \sa gl_selection.
 235  */
 236 static void
 237 write_hit_record(struct gl_context *ctx)
 238 {
 239    GLuint i;
 240    GLuint zmin, zmax, zscale = (~0u);
 241
 242    /* HitMinZ and HitMaxZ are in [0,1].  Multiply these values by */
 243    /* 2^32-1 and round to nearest unsigned integer. */
 244
 245    assert( ctx != NULL ); /* this line magically fixes a SunOS 5.x/gcc bug */
 246    zmin = (GLuint) ((GLfloat) zscale * ctx->Select.HitMinZ);
 247    zmax = (GLuint) ((GLfloat) zscale * ctx->Select.HitMaxZ);
 248
 249    write_record( ctx, ctx->Select.NameStackDepth );
 250    write_record( ctx, zmin );
 251    write_record( ctx, zmax );
 252    for (i = 0; i < ctx->Select.NameStackDepth; i++) {
 253       write_record( ctx, ctx->Select.NameStack[i] );
 254    }
 255
 256    ctx->Select.Hits++;
 257    ctx->Select.HitFlag = GL_FALSE;
 258    ctx->Select.HitMinZ = 1.0;
 259    ctx->Select.HitMaxZ = -1.0;
 260 }
 261
 262
 263 /**
 264  * Initialize the name stack.
 265  *
 266  * Verifies we are in select mode and resets the name stack depth and resets
 267  * the hit record data in gl_selection. Marks new render mode in
 268  * __struct gl_contextRec::NewState.
 269  */
 270 void GLAPIENTRY
 271 _mesa_InitNames( void )
 272 {
 273    GET_CURRENT_CONTEXT(ctx);
 274    FLUSH_VERTICES(ctx, 0);
 275
 276    /* Record the hit before the HitFlag is wiped out again. */
 277    if (ctx->RenderMode == GL_SELECT) {
 278       if (ctx->Select.HitFlag) {
 279          write_hit_record( ctx );
 280       }
 281    }
 282    ctx->Select.NameStackDepth = 0;
 283    ctx->Select.HitFlag = GL_FALSE;
 284    ctx->Select.HitMinZ = 1.0;
 285    ctx->Select.HitMaxZ = 0.0;
 286    ctx->NewState |= _NEW_RENDERMODE;
 287 }
 288
 289
 290 /**
 291  * Load the top-most name of the name stack.
 292  *
 293  * \param name name.
 294  *
 295  * Verifies we are in selection mode and that the name stack is not empty.
 296  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 297  * and replace the top-most name in the stack.
 298  *
 299  * sa __struct gl_contextRec::Select.
 300  */
 301 void GLAPIENTRY
 302 _mesa_LoadName( GLuint name )
 303 {
 304    GET_CURRENT_CONTEXT(ctx);
 305
 306    if (ctx->RenderMode != GL_SELECT) {
 307       return;
 308    }
 309    if (ctx->Select.NameStackDepth == 0) {
 310       _mesa_error( ctx, GL_INVALID_OPERATION, "glLoadName" );
 311       return;
 312    }
 313
 314    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 315
 316    if (ctx->Select.HitFlag) {
 317       write_hit_record( ctx );
 318    }
 319    if (ctx->Select.NameStackDepth < MAX_NAME_STACK_DEPTH) {
 320       ctx->Select.NameStack[ctx->Select.NameStackDepth-1] = name;
 321    }
 322    else {
 323       ctx->Select.NameStack[MAX_NAME_STACK_DEPTH-1] = name;
 324    }
 325 }
 326
 327
 328 /**
 329  * Push a name into the name stack.
 330  *
 331  * \param name name.
 332  *
 333  * Verifies we are in selection mode and that the name stack is not full.
 334  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 335  * and adds the name to the top of the name stack.
 336  *
 337  * sa __struct gl_contextRec::Select.
 338  */
 339 void GLAPIENTRY
 340 _mesa_PushName( GLuint name )
 341 {
 342    GET_CURRENT_CONTEXT(ctx);
 343
 344    if (ctx->RenderMode != GL_SELECT) {
 345       return;
 346    }
 347
 348    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 349    if (ctx->Select.HitFlag) {
 350       write_hit_record( ctx );
 351    }
 352    if (ctx->Select.NameStackDepth >= MAX_NAME_STACK_DEPTH) {
 353       _mesa_error( ctx, GL_STACK_OVERFLOW, "glPushName" );
 354    }
 355    else
 356       ctx->Select.NameStack[ctx->Select.NameStackDepth++] = name;
 357 }
 358
 359
 360 /**
 361  * Pop a name into the name stack.
 362  *
 363  * Verifies we are in selection mode and that the name stack is not empty.
 364  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 365  * and removes top-most name in the name stack.
 366  *
 367  * sa __struct gl_contextRec::Select.
 368  */
 369 void GLAPIENTRY
 370 _mesa_PopName( void )
 371 {
 372    GET_CURRENT_CONTEXT(ctx);
 373
 374    if (ctx->RenderMode != GL_SELECT) {
 375       return;
 376    }
 377
 378    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 379    if (ctx->Select.HitFlag) {
 380       write_hit_record( ctx );
 381    }
 382    if (ctx->Select.NameStackDepth == 0) {
 383       _mesa_error( ctx, GL_STACK_UNDERFLOW, "glPopName" );
 384    }
 385    else
 386       ctx->Select.NameStackDepth--;
 387 }
 388
 389 /*@}*/
 390
 391
 392 /**********************************************************************/
 393 /** \name Render Mode */
 394 /*@{*/
 395
 396 /**
 397  * Set rasterization mode.
 398  *
 399  * \param mode rasterization mode.
 400  *
 401  * \note this function can't be put in a display list.
 402  *
 403  * \sa glRenderMode().
 404  *
 405  * Flushes the vertices and do the necessary cleanup according to the previous
 406  * rasterization mode, such as writing the hit record or resent the select
 407  * buffer index when exiting the select mode. Updates
 408  * __struct gl_contextRec::RenderMode and notifies the driver via the
 409  * dd_function_table::RenderMode callback.
 410  */
 411 GLint GLAPIENTRY
 412 _mesa_RenderMode( GLenum mode )
 413 {
 414    GET_CURRENT_CONTEXT(ctx);
 415    GLint result;
 416    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, 0);
 417
 418    if (MESA_VERBOSE & VERBOSE_API)
 419       _mesa_debug(ctx, "glRenderMode %s\n", _mesa_lookup_enum_by_nr(mode));
 420
 421    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 422
 423    switch (ctx->RenderMode) {
 424       case GL_RENDER:
 425          result = 0;
 426          break;
 427       case GL_SELECT:
 428          if (ctx->Select.HitFlag) {
 429             write_hit_record( ctx );
 430          }
 431          if (ctx->Select.BufferCount > ctx->Select.BufferSize) {
 432             /* overflow */
 433 #ifdef DEBUG
 434             _mesa_warning(ctx, "Feedback buffer overflow");
 435 #endif
 436             result = -1;
 437          }
 438          else {
 439             result = ctx->Select.Hits;
 440          }
 441          ctx->Select.BufferCount = 0;
 442          ctx->Select.Hits = 0;
 443          ctx->Select.NameStackDepth = 0;
 444          break;
 445       case GL_FEEDBACK:
 446          if (ctx->Feedback.Count > ctx->Feedback.BufferSize) {
 447             /* overflow */
 448             result = -1;
 449          }
 450          else {
 451             result = ctx->Feedback.Count;
 452          }
 453          ctx->Feedback.Count = 0;
 454          break;
 455       default:
 456          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 457          return 0;
 458    }
 459
 460    switch (mode) {
 461       case GL_RENDER:
 462          break;
 463       case GL_SELECT:
 464          if (ctx->Select.BufferSize==0) {
 465             /* haven't called glSelectBuffer yet */
 466             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 467          }
 468          break;
 469       case GL_FEEDBACK:
 470          if (ctx->Feedback.BufferSize==0) {
 471             /* haven't called glFeedbackBuffer yet */
 472             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 473          }
 474          break;
 475       default:
 476          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 477          return 0;
 478    }
 479
 480    ctx->RenderMode = mode;
 481    if (ctx->Driver.RenderMode)
 482       ctx->Driver.RenderMode( ctx, mode );
 483
 484    return result;
 485 }
 486
 487 /*@}*/
 488
 489
 490 /**********************************************************************/
 491 /** \name Initialization */
 492 /*@{*/
 493
 494 /**
 495  * Initialize context feedback data.
 496  */
 497 void _mesa_init_feedback( struct gl_context * ctx )
 498 {
 499    /* Feedback */
 500    ctx->Feedback.Type = GL_2D;   /* TODO: verify */
 501    ctx->Feedback.Buffer = NULL;
 502    ctx->Feedback.BufferSize = 0;
 503    ctx->Feedback.Count = 0;
 504
 505    /* Selection/picking */
 506    ctx->Select.Buffer = NULL;
 507    ctx->Select.BufferSize = 0;
 508    ctx->Select.BufferCount = 0;
 509    ctx->Select.Hits = 0;
 510    ctx->Select.NameStackDepth = 0;
 511
 512    /* Miscellaneous */
 513    ctx->RenderMode = GL_RENDER;
 514 }
 515
 516 /*@}*/