src/mesa/main/feedback.c

   1 /**
   2  * \file feedback.c
   3  * Selection and feedback modes functions.
   4  */
   5
   6 /*
   7  * Mesa 3-D graphics library
   8  * Version:  5.1
   9  *
  10  * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a
  13  * copy of this software and associated documentation files (the "Software"),
  14  * to deal in the Software without restriction, including without limitation
  15  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  16  * and/or sell copies of the Software, and to permit persons to whom the
  17  * Software is furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included
  20  * in all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  23  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  26  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  27  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28  */
  29
  30
  31 #include "glheader.h"
  32 #include "colormac.h"
  33 #include "context.h"
  34 #include "enums.h"
  35 #include "feedback.h"
  36 #include "macros.h"
  37 #include "mtypes.h"
  38
  39
  40 #if _HAVE_FULL_GL
  41
  42
  43 #define FB_3D           0x01
  44 #define FB_4D           0x02
  45 #define FB_INDEX        0x04
  46 #define FB_COLOR        0x08
  47 #define FB_TEXTURE      0X10
  48
  49
  50
  51 void GLAPIENTRY
  52 _mesa_FeedbackBuffer( GLsizei size, GLenum type, GLfloat *buffer )
  53 {
  54    GET_CURRENT_CONTEXT(ctx);
  55    ASSERT_OUTSIDE_BEGIN_END(ctx);
  56
  57    if (ctx->RenderMode==GL_FEEDBACK) {
  58       _mesa_error( ctx, GL_INVALID_OPERATION, "glFeedbackBuffer" );
  59       return;
  60    }
  61    if (size<0) {
  62       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(size<0)" );
  63       return;
  64    }
  65    if (!buffer) {
  66       _mesa_error( ctx, GL_INVALID_VALUE, "glFeedbackBuffer(buffer==NULL)" );
  67       ctx->Feedback.BufferSize = 0;
  68       return;
  69    }
  70
  71    switch (type) {
  72       case GL_2D:
  73          ctx->Feedback._Mask = 0;
  74          break;
  75       case GL_3D:
  76          ctx->Feedback._Mask = FB_3D;
  77          break;
  78       case GL_3D_COLOR:
  79          ctx->Feedback._Mask = (FB_3D |
  80                                 (ctx->Visual.rgbMode ? FB_COLOR : FB_INDEX));
  81          break;
  82       case GL_3D_COLOR_TEXTURE:
  83          ctx->Feedback._Mask = (FB_3D |
  84                                 (ctx->Visual.rgbMode ? FB_COLOR : FB_INDEX) |
  85                                 FB_TEXTURE);
  86          break;
  87       case GL_4D_COLOR_TEXTURE:
  88          ctx->Feedback._Mask = (FB_3D | FB_4D |
  89                                 (ctx->Visual.rgbMode ? FB_COLOR : FB_INDEX) |
  90                                 FB_TEXTURE);
  91          break;
  92       default:
  93          _mesa_error( ctx, GL_INVALID_ENUM, "glFeedbackBuffer" );
  94          return;
  95    }
  96
  97    FLUSH_VERTICES(ctx, _NEW_RENDERMODE); /* Always flush */
  98    ctx->Feedback.Type = type;
  99    ctx->Feedback.BufferSize = size;
 100    ctx->Feedback.Buffer = buffer;
 101    ctx->Feedback.Count = 0;                   /* Becaues of this. */
 102 }
 103
 104
 105 void GLAPIENTRY
 106 _mesa_PassThrough( GLfloat token )
 107 {
 108    GET_CURRENT_CONTEXT(ctx);
 109    ASSERT_OUTSIDE_BEGIN_END(ctx);
 110
 111    if (ctx->RenderMode==GL_FEEDBACK) {
 112       FLUSH_VERTICES(ctx, 0);
 113       FEEDBACK_TOKEN( ctx, (GLfloat) (GLint) GL_PASS_THROUGH_TOKEN );
 114       FEEDBACK_TOKEN( ctx, token );
 115    }
 116 }
 117
 118
 119
 120 /*
 121  * Put a vertex into the feedback buffer.
 122  */
 123 void _mesa_feedback_vertex( GLcontext *ctx,
 124                             const GLfloat win[4],
 125                             const GLfloat color[4],
 126                             GLfloat index,
 127                             const GLfloat texcoord[4] )
 128 {
 129 #if 0
 130    {
 131       /* snap window x, y to fractional pixel position */
 132       const GLint snapMask = ~((FIXED_ONE / (1 << SUB_PIXEL_BITS)) - 1);
 133       GLfixed x, y;
 134       x = FloatToFixed(win[0]) & snapMask;
 135       y = FloatToFixed(win[1]) & snapMask;
 136       FEEDBACK_TOKEN(ctx, FixedToFloat(x));
 137       FEEDBACK_TOKEN(ctx, FixedToFloat(y) );
 138    }
 139 #else
 140    FEEDBACK_TOKEN( ctx, win[0] );
 141    FEEDBACK_TOKEN( ctx, win[1] );
 142 #endif
 143    if (ctx->Feedback._Mask & FB_3D) {
 144       FEEDBACK_TOKEN( ctx, win[2] );
 145    }
 146    if (ctx->Feedback._Mask & FB_4D) {
 147       FEEDBACK_TOKEN( ctx, win[3] );
 148    }
 149    if (ctx->Feedback._Mask & FB_INDEX) {
 150       FEEDBACK_TOKEN( ctx, (GLfloat) index );
 151    }
 152    if (ctx->Feedback._Mask & FB_COLOR) {
 153       FEEDBACK_TOKEN( ctx, color[0] );
 154       FEEDBACK_TOKEN( ctx, color[1] );
 155       FEEDBACK_TOKEN( ctx, color[2] );
 156       FEEDBACK_TOKEN( ctx, color[3] );
 157    }
 158    if (ctx->Feedback._Mask & FB_TEXTURE) {
 159       FEEDBACK_TOKEN( ctx, texcoord[0] );
 160       FEEDBACK_TOKEN( ctx, texcoord[1] );
 161       FEEDBACK_TOKEN( ctx, texcoord[2] );
 162       FEEDBACK_TOKEN( ctx, texcoord[3] );
 163    }
 164 }
 165
 166 #endif
 167
 168
 169 /**********************************************************************/
 170 /** \name Selection */
 171 /*@{*/
 172
 173 /**
 174  * Establish a buffer for selection mode values.
 175  *
 176  * \param size buffer size.
 177  * \param buffer buffer.
 178  *
 179  * \sa glSelectBuffer().
 180  *
 181  * \note this function can't be put in a display list.
 182  *
 183  * Verifies we're not in selection mode, flushes the vertices and initialize
 184  * the fields in __GLcontextRec::Select with the given buffer.
 185  */
 186 void GLAPIENTRY
 187 _mesa_SelectBuffer( GLsizei size, GLuint *buffer )
 188 {
 189    GET_CURRENT_CONTEXT(ctx);
 190    ASSERT_OUTSIDE_BEGIN_END(ctx);
 191
 192    if (ctx->RenderMode==GL_SELECT) {
 193       _mesa_error( ctx, GL_INVALID_OPERATION, "glSelectBuffer" );
 194       return;                   /* KW: added return */
 195    }
 196
 197    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 198    ctx->Select.Buffer = buffer;
 199    ctx->Select.BufferSize = size;
 200    ctx->Select.BufferCount = 0;
 201    ctx->Select.HitFlag = GL_FALSE;
 202    ctx->Select.HitMinZ = 1.0;
 203    ctx->Select.HitMaxZ = 0.0;
 204 }
 205
 206
 207 /**
 208  * Write a value of a record into the selection buffer.
 209  *
 210  * \param CTX GL context.
 211  * \param V value.
 212  *
 213  * Verifies there is free space in the buffer to write the value and
 214  * increments the pointer.
 215  */
 216 #define WRITE_RECORD( CTX, V )                                  \
 217         if (CTX->Select.BufferCount < CTX->Select.BufferSize) { \
 218            CTX->Select.Buffer[CTX->Select.BufferCount] = (V);   \
 219         }                                                       \
 220         CTX->Select.BufferCount++;
 221
 222
 223 /**
 224  * Update the hit flag and the maximum and minimum depth values.
 225  *
 226  * \param ctx GL context.
 227  * \param z depth.
 228  *
 229  * Sets gl_selection::HitFlag and updates gl_selection::HitMinZ and
 230  * gl_selection::HitMaxZ.
 231  */
 232 void _mesa_update_hitflag( GLcontext *ctx, GLfloat z )
 233 {
 234    ctx->Select.HitFlag = GL_TRUE;
 235    if (z < ctx->Select.HitMinZ) {
 236       ctx->Select.HitMinZ = z;
 237    }
 238    if (z > ctx->Select.HitMaxZ) {
 239       ctx->Select.HitMaxZ = z;
 240    }
 241 }
 242
 243
 244 /**
 245  * Write the hit record.
 246  *
 247  * \param ctx GL context.
 248  *
 249  * Write the hit record, i.e., the number of names in the stack, the minimum and
 250  * maximum depth values and the number of names in the name stack at the time
 251  * of the event. Resets the hit flag.
 252  *
 253  * \sa gl_selection.
 254  */
 255 static void write_hit_record( GLcontext *ctx )
 256 {
 257    GLuint i;
 258    GLuint zmin, zmax, zscale = (~0u);
 259
 260    /* HitMinZ and HitMaxZ are in [0,1].  Multiply these values by */
 261    /* 2^32-1 and round to nearest unsigned integer. */
 262
 263    assert( ctx != NULL ); /* this line magically fixes a SunOS 5.x/gcc bug */
 264    zmin = (GLuint) ((GLfloat) zscale * ctx->Select.HitMinZ);
 265    zmax = (GLuint) ((GLfloat) zscale * ctx->Select.HitMaxZ);
 266
 267    WRITE_RECORD( ctx, ctx->Select.NameStackDepth );
 268    WRITE_RECORD( ctx, zmin );
 269    WRITE_RECORD( ctx, zmax );
 270    for (i = 0; i < ctx->Select.NameStackDepth; i++) {
 271       WRITE_RECORD( ctx, ctx->Select.NameStack[i] );
 272    }
 273
 274    ctx->Select.Hits++;
 275    ctx->Select.HitFlag = GL_FALSE;
 276    ctx->Select.HitMinZ = 1.0;
 277    ctx->Select.HitMaxZ = -1.0;
 278 }
 279
 280
 281 /**
 282  * Initialize the name stack.
 283  *
 284  * Verifies we are in select mode and resets the name stack depth and resets
 285  * the hit record data in gl_selection. Marks new render mode in
 286  * __GLcontextRec::NewState.
 287  */
 288 void GLAPIENTRY
 289 _mesa_InitNames( void )
 290 {
 291    GET_CURRENT_CONTEXT(ctx);
 292    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 293
 294    /* Record the hit before the HitFlag is wiped out again. */
 295    if (ctx->RenderMode == GL_SELECT) {
 296       if (ctx->Select.HitFlag) {
 297          write_hit_record( ctx );
 298       }
 299    }
 300    ctx->Select.NameStackDepth = 0;
 301    ctx->Select.HitFlag = GL_FALSE;
 302    ctx->Select.HitMinZ = 1.0;
 303    ctx->Select.HitMaxZ = 0.0;
 304    ctx->NewState |= _NEW_RENDERMODE;
 305 }
 306
 307
 308 /**
 309  * Load the top-most name of the name stack.
 310  *
 311  * \param name name.
 312  *
 313  * Verifies we are in selection mode and that the name stack is not empty.
 314  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 315  * and replace the top-most name in the stack.
 316  *
 317  * sa __GLcontextRec::Select.
 318  */
 319 void GLAPIENTRY
 320 _mesa_LoadName( GLuint name )
 321 {
 322    GET_CURRENT_CONTEXT(ctx);
 323    ASSERT_OUTSIDE_BEGIN_END(ctx);
 324
 325    if (ctx->RenderMode != GL_SELECT) {
 326       return;
 327    }
 328    if (ctx->Select.NameStackDepth == 0) {
 329       _mesa_error( ctx, GL_INVALID_OPERATION, "glLoadName" );
 330       return;
 331    }
 332
 333    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 334
 335    if (ctx->Select.HitFlag) {
 336       write_hit_record( ctx );
 337    }
 338    if (ctx->Select.NameStackDepth < MAX_NAME_STACK_DEPTH) {
 339       ctx->Select.NameStack[ctx->Select.NameStackDepth-1] = name;
 340    }
 341    else {
 342       ctx->Select.NameStack[MAX_NAME_STACK_DEPTH-1] = name;
 343    }
 344 }
 345
 346
 347 /**
 348  * Push a name into the name stack.
 349  *
 350  * \param name name.
 351  *
 352  * Verifies we are in selection mode and that the name stack is not full.
 353  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 354  * and adds the name to the top of the name stack.
 355  *
 356  * sa __GLcontextRec::Select.
 357  */
 358 void GLAPIENTRY
 359 _mesa_PushName( GLuint name )
 360 {
 361    GET_CURRENT_CONTEXT(ctx);
 362    ASSERT_OUTSIDE_BEGIN_END(ctx);
 363
 364    if (ctx->RenderMode != GL_SELECT) {
 365       return;
 366    }
 367
 368    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 369    if (ctx->Select.HitFlag) {
 370       write_hit_record( ctx );
 371    }
 372    if (ctx->Select.NameStackDepth >= MAX_NAME_STACK_DEPTH) {
 373       _mesa_error( ctx, GL_STACK_OVERFLOW, "glPushName" );
 374    }
 375    else
 376       ctx->Select.NameStack[ctx->Select.NameStackDepth++] = name;
 377 }
 378
 379
 380 /**
 381  * Pop a name into the name stack.
 382  *
 383  * Verifies we are in selection mode and that the name stack is not empty.
 384  * Flushes vertices. If there is a hit flag writes it (via write_hit_record()),
 385  * and removes top-most name in the name stack.
 386  *
 387  * sa __GLcontextRec::Select.
 388  */
 389 void GLAPIENTRY
 390 _mesa_PopName( void )
 391 {
 392    GET_CURRENT_CONTEXT(ctx);
 393    ASSERT_OUTSIDE_BEGIN_END(ctx);
 394
 395    if (ctx->RenderMode != GL_SELECT) {
 396       return;
 397    }
 398
 399    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 400    if (ctx->Select.HitFlag) {
 401       write_hit_record( ctx );
 402    }
 403    if (ctx->Select.NameStackDepth == 0) {
 404       _mesa_error( ctx, GL_STACK_UNDERFLOW, "glPopName" );
 405    }
 406    else
 407       ctx->Select.NameStackDepth--;
 408 }
 409
 410 /*@}*/
 411
 412
 413 /**********************************************************************/
 414 /** \name Render Mode */
 415 /*@{*/
 416
 417 /**
 418  * Set rasterization mode.
 419  *
 420  * \param mode rasterization mode.
 421  *
 422  * \note this function can't be put in a display list.
 423  *
 424  * \sa glRenderMode().
 425  *
 426  * Flushes the vertices and do the necessary cleanup according to the previous
 427  * rasterization mode, such as writing the hit record or resent the select
 428  * buffer index when exiting the select mode. Updates
 429  * __GLcontextRec::RenderMode and notifies the driver via the
 430  * dd_function_table::RenderMode callback.
 431  */
 432 GLint GLAPIENTRY
 433 _mesa_RenderMode( GLenum mode )
 434 {
 435    GET_CURRENT_CONTEXT(ctx);
 436    GLint result;
 437    ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, 0);
 438
 439    if (MESA_VERBOSE & VERBOSE_API)
 440       _mesa_debug(ctx, "glRenderMode %s\n", _mesa_lookup_enum_by_nr(mode));
 441
 442    FLUSH_VERTICES(ctx, _NEW_RENDERMODE);
 443
 444    switch (ctx->RenderMode) {
 445       case GL_RENDER:
 446          result = 0;
 447          break;
 448       case GL_SELECT:
 449          if (ctx->Select.HitFlag) {
 450             write_hit_record( ctx );
 451          }
 452          if (ctx->Select.BufferCount > ctx->Select.BufferSize) {
 453             /* overflow */
 454 #ifdef DEBUG
 455             _mesa_warning(ctx, "Feedback buffer overflow");
 456 #endif
 457             result = -1;
 458          }
 459          else {
 460             result = ctx->Select.Hits;
 461          }
 462          ctx->Select.BufferCount = 0;
 463          ctx->Select.Hits = 0;
 464          ctx->Select.NameStackDepth = 0;
 465          break;
 466 #if _HAVE_FULL_GL
 467       case GL_FEEDBACK:
 468          if (ctx->Feedback.Count > ctx->Feedback.BufferSize) {
 469             /* overflow */
 470             result = -1;
 471          }
 472          else {
 473             result = ctx->Feedback.Count;
 474          }
 475          ctx->Feedback.Count = 0;
 476          break;
 477 #endif
 478       default:
 479          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 480          return 0;
 481    }
 482
 483    switch (mode) {
 484       case GL_RENDER:
 485          break;
 486       case GL_SELECT:
 487          if (ctx->Select.BufferSize==0) {
 488             /* haven't called glSelectBuffer yet */
 489             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 490          }
 491          break;
 492 #if _HAVE_FULL_GL
 493       case GL_FEEDBACK:
 494          if (ctx->Feedback.BufferSize==0) {
 495             /* haven't called glFeedbackBuffer yet */
 496             _mesa_error( ctx, GL_INVALID_OPERATION, "glRenderMode" );
 497          }
 498          break;
 499 #endif
 500       default:
 501          _mesa_error( ctx, GL_INVALID_ENUM, "glRenderMode" );
 502          return 0;
 503    }
 504
 505    ctx->RenderMode = mode;
 506    if (ctx->Driver.RenderMode)
 507       ctx->Driver.RenderMode( ctx, mode );
 508
 509    return result;
 510 }
 511
 512 /*@}*/
 513
 514
 515 /**********************************************************************/
 516 /** \name Initialization */
 517 /*@{*/
 518
 519 /**
 520  * Initialize context feedback data.
 521  */
 522 void _mesa_init_feedback( GLcontext * ctx )
 523 {
 524    /* Feedback */
 525    ctx->Feedback.Type = GL_2D;   /* TODO: verify */
 526    ctx->Feedback.Buffer = NULL;
 527    ctx->Feedback.BufferSize = 0;
 528    ctx->Feedback.Count = 0;
 529
 530    /* Selection/picking */
 531    ctx->Select.Buffer = NULL;
 532    ctx->Select.BufferSize = 0;
 533    ctx->Select.BufferCount = 0;
 534    ctx->Select.Hits = 0;
 535    ctx->Select.NameStackDepth = 0;
 536
 537    /* Miscellaneous */
 538    ctx->RenderMode = GL_RENDER;
 539 }
 540
 541 /*@}*/