src/mesa/main/texstate.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.5
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   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  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file texstate.c
  27  *
  28  * Texture state handling.
  29  */
  30
  31 #include "glheader.h"
  32 #include "mfeatures.h"
  33 #include "colormac.h"
  34 #if FEATURE_colortable
  35 #include "colortab.h"
  36 #endif
  37 #include "context.h"
  38 #include "enums.h"
  39 #include "macros.h"
  40 #include "texcompress.h"
  41 #include "texobj.h"
  42 #include "teximage.h"
  43 #include "texstate.h"
  44 #include "texenvprogram.h"
  45 #include "mtypes.h"
  46
  47
  48
  49 /**
  50  * Default texture combine environment state.  This is used to initialize
  51  * a context's texture units and as the basis for converting "classic"
  52  * texture environmnets to ARB_texture_env_combine style values.
  53  */
  54 static const struct gl_tex_env_combine_state default_combine_state = {
  55    GL_MODULATE, GL_MODULATE,
  56    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  57    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  58    { GL_SRC_COLOR, GL_SRC_COLOR, GL_SRC_ALPHA, GL_SRC_ALPHA },
  59    { GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA },
  60    0, 0,
  61    2, 2
  62 };
  63
  64
  65
  66 /**
  67  * Used by glXCopyContext to copy texture state from one context to another.
  68  */
  69 void
  70 _mesa_copy_texture_state( const GLcontext *src, GLcontext *dst )
  71 {
  72    GLuint u, tex;
  73
  74    ASSERT(src);
  75    ASSERT(dst);
  76
  77    dst->Texture.CurrentUnit = src->Texture.CurrentUnit;
  78    dst->Texture._GenFlags = src->Texture._GenFlags;
  79    dst->Texture._TexGenEnabled = src->Texture._TexGenEnabled;
  80    dst->Texture._TexMatEnabled = src->Texture._TexMatEnabled;
  81    dst->Texture.SharedPalette = src->Texture.SharedPalette;
  82
  83    /* per-unit state */
  84    for (u = 0; u < src->Const.MaxTextureImageUnits; u++) {
  85       dst->Texture.Unit[u].Enabled = src->Texture.Unit[u].Enabled;
  86       dst->Texture.Unit[u].EnvMode = src->Texture.Unit[u].EnvMode;
  87       COPY_4V(dst->Texture.Unit[u].EnvColor, src->Texture.Unit[u].EnvColor);
  88       dst->Texture.Unit[u].TexGenEnabled = src->Texture.Unit[u].TexGenEnabled;
  89       dst->Texture.Unit[u].GenS = src->Texture.Unit[u].GenS;
  90       dst->Texture.Unit[u].GenT = src->Texture.Unit[u].GenT;
  91       dst->Texture.Unit[u].GenR = src->Texture.Unit[u].GenR;
  92       dst->Texture.Unit[u].GenQ = src->Texture.Unit[u].GenQ;
  93       dst->Texture.Unit[u].LodBias = src->Texture.Unit[u].LodBias;
  94
  95       /* GL_EXT_texture_env_combine */
  96       dst->Texture.Unit[u].Combine = src->Texture.Unit[u].Combine;
  97
  98       /* GL_ATI_envmap_bumpmap - need this? */
  99       dst->Texture.Unit[u].BumpTarget = src->Texture.Unit[u].BumpTarget;
 100       COPY_4V(dst->Texture.Unit[u].RotMatrix, src->Texture.Unit[u].RotMatrix);
 101
 102
 103       /* copy texture object bindings, not contents of texture objects */
 104       _mesa_lock_context_textures(dst);
 105
 106       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 107          _mesa_reference_texobj(&dst->Texture.Unit[u].CurrentTex[tex],
 108                                 src->Texture.Unit[u].CurrentTex[tex]);
 109       }
 110
 111       _mesa_unlock_context_textures(dst);
 112    }
 113 }
 114
 115
 116 /*
 117  * For debugging
 118  */
 119 void
 120 _mesa_print_texunit_state( GLcontext *ctx, GLuint unit )
 121 {
 122    const struct gl_texture_unit *texUnit = ctx->Texture.Unit + unit;
 123    _mesa_printf("Texture Unit %d\n", unit);
 124    _mesa_printf("  GL_TEXTURE_ENV_MODE = %s\n", _mesa_lookup_enum_by_nr(texUnit->EnvMode));
 125    _mesa_printf("  GL_COMBINE_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeRGB));
 126    _mesa_printf("  GL_COMBINE_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeA));
 127    _mesa_printf("  GL_SOURCE0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[0]));
 128    _mesa_printf("  GL_SOURCE1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[1]));
 129    _mesa_printf("  GL_SOURCE2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[2]));
 130    _mesa_printf("  GL_SOURCE0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[0]));
 131    _mesa_printf("  GL_SOURCE1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[1]));
 132    _mesa_printf("  GL_SOURCE2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[2]));
 133    _mesa_printf("  GL_OPERAND0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[0]));
 134    _mesa_printf("  GL_OPERAND1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[1]));
 135    _mesa_printf("  GL_OPERAND2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[2]));
 136    _mesa_printf("  GL_OPERAND0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[0]));
 137    _mesa_printf("  GL_OPERAND1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[1]));
 138    _mesa_printf("  GL_OPERAND2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[2]));
 139    _mesa_printf("  GL_RGB_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftRGB);
 140    _mesa_printf("  GL_ALPHA_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftA);
 141    _mesa_printf("  GL_TEXTURE_ENV_COLOR = (%f, %f, %f, %f)\n", texUnit->EnvColor[0], texUnit->EnvColor[1], texUnit->EnvColor[2], texUnit->EnvColor[3]);
 142 }
 143
 144
 145
 146 /**********************************************************************/
 147 /*                       Texture Environment                          */
 148 /**********************************************************************/
 149
 150 /**
 151  * Convert "classic" texture environment to ARB_texture_env_combine style
 152  * environments.
 153  *
 154  * \param state  texture_env_combine state vector to be filled-in.
 155  * \param mode   Classic texture environment mode (i.e., \c GL_REPLACE,
 156  *               \c GL_BLEND, \c GL_DECAL, etc.).
 157  * \param texBaseFormat  Base format of the texture associated with the
 158  *               texture unit.
 159  */
 160 static void
 161 calculate_derived_texenv( struct gl_tex_env_combine_state *state,
 162                           GLenum mode, GLenum texBaseFormat )
 163 {
 164    GLenum mode_rgb;
 165    GLenum mode_a;
 166
 167    *state = default_combine_state;
 168
 169    switch (texBaseFormat) {
 170    case GL_ALPHA:
 171       state->SourceRGB[0] = GL_PREVIOUS;
 172       break;
 173
 174    case GL_LUMINANCE_ALPHA:
 175    case GL_INTENSITY:
 176    case GL_RGBA:
 177       break;
 178
 179    case GL_LUMINANCE:
 180    case GL_RGB:
 181    case GL_YCBCR_MESA:
 182    case GL_DUDV_ATI:
 183       state->SourceA[0] = GL_PREVIOUS;
 184       break;
 185
 186    default:
 187       _mesa_problem(NULL,
 188                     "Invalid texBaseFormat 0x%x in calculate_derived_texenv",
 189                     texBaseFormat);
 190       return;
 191    }
 192
 193    if (mode == GL_REPLACE_EXT)
 194       mode = GL_REPLACE;
 195
 196    switch (mode) {
 197    case GL_REPLACE:
 198    case GL_MODULATE:
 199       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : mode;
 200       mode_a   = mode;
 201       break;
 202
 203    case GL_DECAL:
 204       mode_rgb = GL_INTERPOLATE;
 205       mode_a   = GL_REPLACE;
 206
 207       state->SourceA[0] = GL_PREVIOUS;
 208
 209       /* Having alpha / luminance / intensity textures replace using the
 210        * incoming fragment color matches the definition in NV_texture_shader.
 211        * The 1.5 spec simply marks these as "undefined".
 212        */
 213       switch (texBaseFormat) {
 214       case GL_ALPHA:
 215       case GL_LUMINANCE:
 216       case GL_LUMINANCE_ALPHA:
 217       case GL_INTENSITY:
 218          state->SourceRGB[0] = GL_PREVIOUS;
 219          break;
 220       case GL_RGB:
 221       case GL_YCBCR_MESA:
 222       case GL_DUDV_ATI:
 223          mode_rgb = GL_REPLACE;
 224          break;
 225       case GL_RGBA:
 226          state->SourceRGB[2] = GL_TEXTURE;
 227          break;
 228       }
 229       break;
 230
 231    case GL_BLEND:
 232       mode_rgb = GL_INTERPOLATE;
 233       mode_a   = GL_MODULATE;
 234
 235       switch (texBaseFormat) {
 236       case GL_ALPHA:
 237          mode_rgb = GL_REPLACE;
 238          break;
 239       case GL_INTENSITY:
 240          mode_a = GL_INTERPOLATE;
 241          state->SourceA[0] = GL_CONSTANT;
 242          state->OperandA[2] = GL_SRC_ALPHA;
 243          /* FALLTHROUGH */
 244       case GL_LUMINANCE:
 245       case GL_RGB:
 246       case GL_LUMINANCE_ALPHA:
 247       case GL_RGBA:
 248       case GL_YCBCR_MESA:
 249       case GL_DUDV_ATI:
 250          state->SourceRGB[2] = GL_TEXTURE;
 251          state->SourceA[2]   = GL_TEXTURE;
 252          state->SourceRGB[0] = GL_CONSTANT;
 253          state->OperandRGB[2] = GL_SRC_COLOR;
 254          break;
 255       }
 256       break;
 257
 258    case GL_ADD:
 259       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : GL_ADD;
 260       mode_a   = (texBaseFormat == GL_INTENSITY) ? GL_ADD : GL_MODULATE;
 261       break;
 262
 263    default:
 264       _mesa_problem(NULL,
 265                     "Invalid texture env mode 0x%x in calculate_derived_texenv",
 266                     mode);
 267       return;
 268    }
 269
 270    state->ModeRGB = (state->SourceRGB[0] != GL_PREVIOUS)
 271        ? mode_rgb : GL_REPLACE;
 272    state->ModeA   = (state->SourceA[0]   != GL_PREVIOUS)
 273        ? mode_a   : GL_REPLACE;
 274 }
 275
 276
 277
 278
 279 /* GL_ARB_multitexture */
 280 void GLAPIENTRY
 281 _mesa_ActiveTextureARB(GLenum texture)
 282 {
 283    GET_CURRENT_CONTEXT(ctx);
 284    const GLuint texUnit = texture - GL_TEXTURE0;
 285    ASSERT_OUTSIDE_BEGIN_END(ctx);
 286
 287    if (MESA_VERBOSE & (VERBOSE_API|VERBOSE_TEXTURE))
 288       _mesa_debug(ctx, "glActiveTexture %s\n",
 289                   _mesa_lookup_enum_by_nr(texture));
 290
 291    if (texUnit >= ctx->Const.MaxTextureImageUnits) {
 292       _mesa_error(ctx, GL_INVALID_ENUM, "glActiveTexture(texture)");
 293       return;
 294    }
 295
 296    if (ctx->Texture.CurrentUnit == texUnit)
 297       return;
 298
 299    FLUSH_VERTICES(ctx, _NEW_TEXTURE);
 300
 301    ctx->Texture.CurrentUnit = texUnit;
 302    if (ctx->Transform.MatrixMode == GL_TEXTURE) {
 303       /* update current stack pointer */
 304       ctx->CurrentStack = &ctx->TextureMatrixStack[texUnit];
 305    }
 306
 307    if (ctx->Driver.ActiveTexture) {
 308       (*ctx->Driver.ActiveTexture)( ctx, (GLuint) texUnit );
 309    }
 310 }
 311
 312
 313 /* GL_ARB_multitexture */
 314 void GLAPIENTRY
 315 _mesa_ClientActiveTextureARB(GLenum texture)
 316 {
 317    GET_CURRENT_CONTEXT(ctx);
 318    GLuint texUnit = texture - GL_TEXTURE0;
 319    ASSERT_OUTSIDE_BEGIN_END(ctx);
 320
 321    if (texUnit >= ctx->Const.MaxTextureCoordUnits) {
 322       _mesa_error(ctx, GL_INVALID_ENUM, "glClientActiveTexture(texture)");
 323       return;
 324    }
 325
 326    FLUSH_VERTICES(ctx, _NEW_ARRAY);
 327    ctx->Array.ActiveTexture = texUnit;
 328 }
 329
 330
 331
 332 /**********************************************************************/
 333 /*****                    State management                        *****/
 334 /**********************************************************************/
 335
 336
 337 /**
 338  * \note This routine refers to derived texture attribute values to
 339  * compute the ENABLE_TEXMAT flags, but is only called on
 340  * _NEW_TEXTURE_MATRIX.  On changes to _NEW_TEXTURE, the ENABLE_TEXMAT
 341  * flags are updated by _mesa_update_textures(), below.
 342  *
 343  * \param ctx GL context.
 344  */
 345 static void
 346 update_texture_matrices( GLcontext *ctx )
 347 {
 348    GLuint u;
 349
 350    ctx->Texture._TexMatEnabled = 0x0;
 351
 352    for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
 353       if (_math_matrix_is_dirty(ctx->TextureMatrixStack[u].Top)) {
 354          _math_matrix_analyse( ctx->TextureMatrixStack[u].Top );
 355
 356          if (ctx->Texture.Unit[u]._ReallyEnabled &&
 357              ctx->TextureMatrixStack[u].Top->type != MATRIX_IDENTITY)
 358             ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(u);
 359
 360          if (ctx->Driver.TextureMatrix)
 361             ctx->Driver.TextureMatrix( ctx, u, ctx->TextureMatrixStack[u].Top);
 362       }
 363    }
 364 }
 365
 366
 367 /**
 368  * Examine texture unit's combine/env state to update derived state.
 369  */
 370 static void
 371 update_tex_combine(GLcontext *ctx, struct gl_texture_unit *texUnit)
 372 {
 373    struct gl_tex_env_combine_state *combine;
 374
 375    /* Set the texUnit->_CurrentCombine field to point to the user's combiner
 376     * state, or the combiner state which is derived from traditional texenv
 377     * mode.
 378     */
 379    if (texUnit->EnvMode == GL_COMBINE ||
 380        texUnit->EnvMode == GL_COMBINE4_NV) {
 381       texUnit->_CurrentCombine = & texUnit->Combine;
 382    }
 383    else {
 384       const struct gl_texture_object *texObj = texUnit->_Current;
 385       GLenum format = texObj->Image[0][texObj->BaseLevel]->_BaseFormat;
 386       if (format == GL_COLOR_INDEX) {
 387          format = GL_RGBA;  /* a bit of a hack */
 388       }
 389       else if (format == GL_DEPTH_COMPONENT ||
 390                format == GL_DEPTH_STENCIL_EXT) {
 391          format = texObj->DepthMode;
 392       }
 393       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 394       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 395    }
 396
 397    combine = texUnit->_CurrentCombine;
 398
 399    /* Determine number of source RGB terms in the combiner function */
 400    switch (combine->ModeRGB) {
 401    case GL_REPLACE:
 402       combine->_NumArgsRGB = 1;
 403       break;
 404    case GL_ADD:
 405    case GL_ADD_SIGNED:
 406       if (texUnit->EnvMode == GL_COMBINE4_NV)
 407          combine->_NumArgsRGB = 4;
 408       else
 409          combine->_NumArgsRGB = 2;
 410       break;
 411    case GL_MODULATE:
 412    case GL_SUBTRACT:
 413    case GL_DOT3_RGB:
 414    case GL_DOT3_RGBA:
 415    case GL_DOT3_RGB_EXT:
 416    case GL_DOT3_RGBA_EXT:
 417       combine->_NumArgsRGB = 2;
 418       break;
 419    case GL_INTERPOLATE:
 420    case GL_MODULATE_ADD_ATI:
 421    case GL_MODULATE_SIGNED_ADD_ATI:
 422    case GL_MODULATE_SUBTRACT_ATI:
 423       combine->_NumArgsRGB = 3;
 424       break;
 425    case GL_BUMP_ENVMAP_ATI:
 426       /* no real arguments for this case */
 427       combine->_NumArgsRGB = 0;
 428       break;
 429    default:
 430       combine->_NumArgsRGB = 0;
 431       _mesa_problem(ctx, "invalid RGB combine mode in update_texture_state");
 432       return;
 433    }
 434
 435    /* Determine number of source Alpha terms in the combiner function */
 436    switch (combine->ModeA) {
 437    case GL_REPLACE:
 438       combine->_NumArgsA = 1;
 439       break;
 440    case GL_ADD:
 441    case GL_ADD_SIGNED:
 442       if (texUnit->EnvMode == GL_COMBINE4_NV)
 443          combine->_NumArgsA = 4;
 444       else
 445          combine->_NumArgsA = 2;
 446       break;
 447    case GL_MODULATE:
 448    case GL_SUBTRACT:
 449       combine->_NumArgsA = 2;
 450       break;
 451    case GL_INTERPOLATE:
 452    case GL_MODULATE_ADD_ATI:
 453    case GL_MODULATE_SIGNED_ADD_ATI:
 454    case GL_MODULATE_SUBTRACT_ATI:
 455       combine->_NumArgsA = 3;
 456       break;
 457    default:
 458       combine->_NumArgsA = 0;
 459       _mesa_problem(ctx, "invalid Alpha combine mode in update_texture_state");
 460       break;
 461    }
 462 }
 463
 464
 465 /**
 466  * \note This routine refers to derived texture matrix values to
 467  * compute the ENABLE_TEXMAT flags, but is only called on
 468  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 469  * flags are updated by _mesa_update_texture_matrices, above.
 470  *
 471  * \param ctx GL context.
 472  */
 473 static void
 474 update_texture_state( GLcontext *ctx )
 475 {
 476    GLuint unit;
 477    struct gl_fragment_program *fprog = NULL;
 478    struct gl_vertex_program *vprog = NULL;
 479    GLbitfield enabledFragUnits = 0x0;
 480
 481    if (ctx->Shader.CurrentProgram &&
 482        ctx->Shader.CurrentProgram->LinkStatus) {
 483       fprog = ctx->Shader.CurrentProgram->FragmentProgram;
 484       vprog = ctx->Shader.CurrentProgram->VertexProgram;
 485    }
 486    else {
 487       if (ctx->FragmentProgram._Enabled) {
 488          fprog = ctx->FragmentProgram.Current;
 489       }
 490       if (ctx->VertexProgram._Enabled) {
 491          /* XXX enable this if/when non-shader vertex programs get
 492           * texture fetches:
 493          vprog = ctx->VertexProgram.Current;
 494          */
 495       }
 496    }
 497
 498    /* TODO: only set this if there are actual changes */
 499    ctx->NewState |= _NEW_TEXTURE;
 500
 501    ctx->Texture._EnabledUnits = 0x0;
 502    ctx->Texture._GenFlags = 0x0;
 503    ctx->Texture._TexMatEnabled = 0x0;
 504    ctx->Texture._TexGenEnabled = 0x0;
 505
 506    /*
 507     * Update texture unit state.
 508     */
 509    for (unit = 0; unit < ctx->Const.MaxTextureImageUnits; unit++) {
 510       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 511       GLbitfield enabledVertTargets = 0x0;
 512       GLbitfield enabledFragTargets = 0x0;
 513       GLbitfield enabledTargets = 0x0;
 514       GLuint texIndex;
 515
 516       /* Get the bitmask of texture target enables.
 517        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 518        * which texture targets are enabled (fixed function) or referenced
 519        * by a fragment shader/program.  When multiple flags are set, we'll
 520        * settle on the one with highest priority (see below).
 521        */
 522       if (vprog) {
 523          enabledVertTargets |= vprog->Base.TexturesUsed[unit];
 524       }
 525
 526       if (fprog) {
 527          enabledFragTargets |= fprog->Base.TexturesUsed[unit];
 528       }
 529       else {
 530          /* fixed-function fragment program */
 531          enabledFragTargets |= texUnit->Enabled;
 532       }
 533
 534       enabledTargets = enabledVertTargets | enabledFragTargets;
 535
 536       texUnit->_ReallyEnabled = 0x0;
 537
 538       if (enabledTargets == 0x0) {
 539          /* neither vertex nor fragment processing uses this unit */
 540          continue;
 541       }
 542
 543       /* Look for the highest priority texture target that's enabled (or used
 544        * by the vert/frag shaders) and "complete".  That's the one we'll use
 545        * for texturing.  If we're using vert/frag program we're guaranteed
 546        * that bitcount(enabledBits) <= 1.
 547        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 548        */
 549       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 550          if (enabledTargets & (1 << texIndex)) {
 551             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 552             if (!texObj->_Complete) {
 553                _mesa_test_texobj_completeness(ctx, texObj);
 554             }
 555             if (texObj->_Complete) {
 556                texUnit->_ReallyEnabled = 1 << texIndex;
 557                _mesa_reference_texobj(&texUnit->_Current, texObj);
 558                break;
 559             }
 560          }
 561       }
 562
 563       if (!texUnit->_ReallyEnabled) {
 564          if (fprog) {
 565             /* If we get here it means the shader is expecting a texture
 566              * object, but there isn't one (or it's incomplete).  Use the
 567              * fallback texture.
 568              */
 569             struct gl_texture_object *texObj = _mesa_get_fallback_texture(ctx);
 570             texUnit->_ReallyEnabled = 1 << TEXTURE_2D_INDEX;
 571             _mesa_reference_texobj(&texUnit->_Current, texObj);
 572          }
 573          else {
 574             /* fixed-function: texture unit is really disabled */
 575             continue;
 576          }
 577       }
 578
 579       /* if we get here, we know this texture unit is enabled */
 580
 581       ctx->Texture._EnabledUnits |= (1 << unit);
 582
 583       if (enabledFragTargets)
 584          enabledFragUnits |= (1 << unit);
 585
 586       update_tex_combine(ctx, texUnit);
 587    }
 588
 589
 590    /* Determine which texture coordinate sets are actually needed */
 591    if (fprog) {
 592       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 593       ctx->Texture._EnabledCoordUnits
 594          = (fprog->Base.InputsRead >> FRAG_ATTRIB_TEX0) & coordMask;
 595    }
 596    else {
 597       ctx->Texture._EnabledCoordUnits = enabledFragUnits;
 598    }
 599
 600    /* Setup texgen for those texture coordinate sets that are in use */
 601    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 602       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 603
 604       texUnit->_GenFlags = 0x0;
 605
 606       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 607          continue;
 608
 609       if (texUnit->TexGenEnabled) {
 610          if (texUnit->TexGenEnabled & S_BIT) {
 611             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 612          }
 613          if (texUnit->TexGenEnabled & T_BIT) {
 614             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 615          }
 616          if (texUnit->TexGenEnabled & R_BIT) {
 617             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 618          }
 619          if (texUnit->TexGenEnabled & Q_BIT) {
 620             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 621          }
 622
 623          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 624          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 625       }
 626
 627       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 628          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 629    }
 630 }
 631
 632
 633 /**
 634  * Update texture-related derived state.
 635  */
 636 void
 637 _mesa_update_texture( GLcontext *ctx, GLuint new_state )
 638 {
 639    if (new_state & _NEW_TEXTURE_MATRIX)
 640       update_texture_matrices( ctx );
 641
 642    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 643       update_texture_state( ctx );
 644 }
 645
 646
 647 /**********************************************************************/
 648 /*****                      Initialization                        *****/
 649 /**********************************************************************/
 650
 651 /**
 652  * Allocate the proxy textures for the given context.
 653  *
 654  * \param ctx the context to allocate proxies for.
 655  *
 656  * \return GL_TRUE on success, or GL_FALSE on failure
 657  *
 658  * If run out of memory part way through the allocations, clean up and return
 659  * GL_FALSE.
 660  */
 661 static GLboolean
 662 alloc_proxy_textures( GLcontext *ctx )
 663 {
 664    static const GLenum targets[] = {
 665       GL_TEXTURE_1D,
 666       GL_TEXTURE_2D,
 667       GL_TEXTURE_3D,
 668       GL_TEXTURE_CUBE_MAP_ARB,
 669       GL_TEXTURE_RECTANGLE_NV,
 670       GL_TEXTURE_1D_ARRAY_EXT,
 671       GL_TEXTURE_2D_ARRAY_EXT
 672    };
 673    GLint tgt;
 674
 675    ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 676
 677    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 678       if (!(ctx->Texture.ProxyTex[tgt]
 679             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 680          /* out of memory, free what we did allocate */
 681          while (--tgt >= 0) {
 682             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 683          }
 684          return GL_FALSE;
 685       }
 686    }
 687
 688    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 689    return GL_TRUE;
 690 }
 691
 692
 693 /**
 694  * Initialize a texture unit.
 695  *
 696  * \param ctx GL context.
 697  * \param unit texture unit number to be initialized.
 698  */
 699 static void
 700 init_texture_unit( GLcontext *ctx, GLuint unit )
 701 {
 702    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 703    GLuint tex;
 704
 705    texUnit->EnvMode = GL_MODULATE;
 706    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 707
 708    texUnit->Combine = default_combine_state;
 709    texUnit->_EnvMode = default_combine_state;
 710    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 711    texUnit->BumpTarget = GL_TEXTURE0;
 712
 713    texUnit->TexGenEnabled = 0x0;
 714    texUnit->GenS.Mode = GL_EYE_LINEAR;
 715    texUnit->GenT.Mode = GL_EYE_LINEAR;
 716    texUnit->GenR.Mode = GL_EYE_LINEAR;
 717    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 718    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 719    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 720    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 721    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 722
 723    /* Yes, these plane coefficients are correct! */
 724    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 725    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 726    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 727    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 728    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 729    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 730    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 731    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 732    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 733    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 734    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 735    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 736    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 737    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 738    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 739    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 740    /* no mention of this in spec, but maybe id matrix expected? */
 741    ASSIGN_4V( texUnit->RotMatrix, 1.0, 0.0, 0.0, 1.0 );
 742
 743    /* initialize current texture object ptrs to the shared default objects */
 744    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 745       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 746                              ctx->Shared->DefaultTex[tex]);
 747    }
 748 }
 749
 750
 751 /**
 752  * Initialize texture state for the given context.
 753  */
 754 GLboolean
 755 _mesa_init_texture(GLcontext *ctx)
 756 {
 757    GLuint u;
 758
 759    /* Texture group */
 760    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 761    ctx->Texture._EnabledUnits = 0x0;
 762    ctx->Texture.SharedPalette = GL_FALSE;
 763 #if FEATURE_colortable
 764    _mesa_init_colortable(&ctx->Texture.Palette);
 765 #endif
 766
 767    for (u = 0; u < MAX_TEXTURE_UNITS; u++)
 768       init_texture_unit(ctx, u);
 769
 770    /* After we're done initializing the context's texture state the default
 771     * texture objects' refcounts should be at least MAX_TEXTURE_UNITS + 1.
 772     */
 773    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 774           >= MAX_TEXTURE_UNITS + 1);
 775
 776    /* Allocate proxy textures */
 777    if (!alloc_proxy_textures( ctx ))
 778       return GL_FALSE;
 779
 780    return GL_TRUE;
 781 }
 782
 783
 784 /**
 785  * Free dynamically-allocted texture data attached to the given context.
 786  */
 787 void
 788 _mesa_free_texture_data(GLcontext *ctx)
 789 {
 790    GLuint u, tgt;
 791
 792    /* unreference current textures */
 793    for (u = 0; u < MAX_TEXTURE_IMAGE_UNITS; u++) {
 794       /* The _Current texture could account for another reference */
 795       _mesa_reference_texobj(&ctx->Texture.Unit[u]._Current, NULL);
 796
 797       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 798          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 799       }
 800    }
 801
 802    /* Free proxy texture objects */
 803    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 804       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 805
 806 #if FEATURE_colortable
 807    for (u = 0; u < MAX_TEXTURE_IMAGE_UNITS; u++)
 808       _mesa_free_colortable_data(&ctx->Texture.Unit[u].ColorTable);
 809 #endif
 810 }
 811
 812
 813 /**
 814  * Update the default texture objects in the given context to reference those
 815  * specified in the shared state and release those referencing the old
 816  * shared state.
 817  */
 818 void
 819 _mesa_update_default_objects_texture(GLcontext *ctx)
 820 {
 821    GLuint u, tex;
 822
 823    for (u = 0; u < MAX_TEXTURE_UNITS; u++) {
 824       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 825       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 826          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 827                                 ctx->Shared->DefaultTex[tex]);
 828       }
 829    }
 830 }