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       /* copy texture object bindings, not contents of texture objects */
  99       _mesa_lock_context_textures(dst);
 100
 101       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 102          _mesa_reference_texobj(&dst->Texture.Unit[u].CurrentTex[tex],
 103                                 src->Texture.Unit[u].CurrentTex[tex]);
 104       }
 105
 106       _mesa_unlock_context_textures(dst);
 107    }
 108 }
 109
 110
 111 /*
 112  * For debugging
 113  */
 114 void
 115 _mesa_print_texunit_state( GLcontext *ctx, GLuint unit )
 116 {
 117    const struct gl_texture_unit *texUnit = ctx->Texture.Unit + unit;
 118    _mesa_printf("Texture Unit %d\n", unit);
 119    _mesa_printf("  GL_TEXTURE_ENV_MODE = %s\n", _mesa_lookup_enum_by_nr(texUnit->EnvMode));
 120    _mesa_printf("  GL_COMBINE_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeRGB));
 121    _mesa_printf("  GL_COMBINE_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeA));
 122    _mesa_printf("  GL_SOURCE0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[0]));
 123    _mesa_printf("  GL_SOURCE1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[1]));
 124    _mesa_printf("  GL_SOURCE2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[2]));
 125    _mesa_printf("  GL_SOURCE0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[0]));
 126    _mesa_printf("  GL_SOURCE1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[1]));
 127    _mesa_printf("  GL_SOURCE2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[2]));
 128    _mesa_printf("  GL_OPERAND0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[0]));
 129    _mesa_printf("  GL_OPERAND1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[1]));
 130    _mesa_printf("  GL_OPERAND2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[2]));
 131    _mesa_printf("  GL_OPERAND0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[0]));
 132    _mesa_printf("  GL_OPERAND1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[1]));
 133    _mesa_printf("  GL_OPERAND2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[2]));
 134    _mesa_printf("  GL_RGB_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftRGB);
 135    _mesa_printf("  GL_ALPHA_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftA);
 136    _mesa_printf("  GL_TEXTURE_ENV_COLOR = (%f, %f, %f, %f)\n", texUnit->EnvColor[0], texUnit->EnvColor[1], texUnit->EnvColor[2], texUnit->EnvColor[3]);
 137 }
 138
 139
 140
 141 /**********************************************************************/
 142 /*                       Texture Environment                          */
 143 /**********************************************************************/
 144
 145 /**
 146  * Convert "classic" texture environment to ARB_texture_env_combine style
 147  * environments.
 148  *
 149  * \param state  texture_env_combine state vector to be filled-in.
 150  * \param mode   Classic texture environment mode (i.e., \c GL_REPLACE,
 151  *               \c GL_BLEND, \c GL_DECAL, etc.).
 152  * \param texBaseFormat  Base format of the texture associated with the
 153  *               texture unit.
 154  */
 155 static void
 156 calculate_derived_texenv( struct gl_tex_env_combine_state *state,
 157                           GLenum mode, GLenum texBaseFormat )
 158 {
 159    GLenum mode_rgb;
 160    GLenum mode_a;
 161
 162    *state = default_combine_state;
 163
 164    switch (texBaseFormat) {
 165    case GL_ALPHA:
 166       state->SourceRGB[0] = GL_PREVIOUS;
 167       break;
 168
 169    case GL_LUMINANCE_ALPHA:
 170    case GL_INTENSITY:
 171    case GL_RGBA:
 172       break;
 173
 174    case GL_LUMINANCE:
 175    case GL_RGB:
 176    case GL_YCBCR_MESA:
 177       state->SourceA[0] = GL_PREVIOUS;
 178       break;
 179
 180    default:
 181       _mesa_problem(NULL, "Invalid texBaseFormat in calculate_derived_texenv");
 182       return;
 183    }
 184
 185    if (mode == GL_REPLACE_EXT)
 186       mode = GL_REPLACE;
 187
 188    switch (mode) {
 189    case GL_REPLACE:
 190    case GL_MODULATE:
 191       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : mode;
 192       mode_a   = mode;
 193       break;
 194
 195    case GL_DECAL:
 196       mode_rgb = GL_INTERPOLATE;
 197       mode_a   = GL_REPLACE;
 198
 199       state->SourceA[0] = GL_PREVIOUS;
 200
 201       /* Having alpha / luminance / intensity textures replace using the
 202        * incoming fragment color matches the definition in NV_texture_shader.
 203        * The 1.5 spec simply marks these as "undefined".
 204        */
 205       switch (texBaseFormat) {
 206       case GL_ALPHA:
 207       case GL_LUMINANCE:
 208       case GL_LUMINANCE_ALPHA:
 209       case GL_INTENSITY:
 210          state->SourceRGB[0] = GL_PREVIOUS;
 211          break;
 212       case GL_RGB:
 213       case GL_YCBCR_MESA:
 214          mode_rgb = GL_REPLACE;
 215          break;
 216       case GL_RGBA:
 217          state->SourceRGB[2] = GL_TEXTURE;
 218          break;
 219       }
 220       break;
 221
 222    case GL_BLEND:
 223       mode_rgb = GL_INTERPOLATE;
 224       mode_a   = GL_MODULATE;
 225
 226       switch (texBaseFormat) {
 227       case GL_ALPHA:
 228          mode_rgb = GL_REPLACE;
 229          break;
 230       case GL_INTENSITY:
 231          mode_a = GL_INTERPOLATE;
 232          state->SourceA[0] = GL_CONSTANT;
 233          state->OperandA[2] = GL_SRC_ALPHA;
 234          /* FALLTHROUGH */
 235       case GL_LUMINANCE:
 236       case GL_RGB:
 237       case GL_LUMINANCE_ALPHA:
 238       case GL_RGBA:
 239       case GL_YCBCR_MESA:
 240          state->SourceRGB[2] = GL_TEXTURE;
 241          state->SourceA[2]   = GL_TEXTURE;
 242          state->SourceRGB[0] = GL_CONSTANT;
 243          state->OperandRGB[2] = GL_SRC_COLOR;
 244          break;
 245       }
 246       break;
 247
 248    case GL_ADD:
 249       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : GL_ADD;
 250       mode_a   = (texBaseFormat == GL_INTENSITY) ? GL_ADD : GL_MODULATE;
 251       break;
 252
 253    default:
 254       _mesa_problem(NULL,
 255                     "Invalid texture env mode in calculate_derived_texenv");
 256       return;
 257    }
 258
 259    state->ModeRGB = (state->SourceRGB[0] != GL_PREVIOUS)
 260        ? mode_rgb : GL_REPLACE;
 261    state->ModeA   = (state->SourceA[0]   != GL_PREVIOUS)
 262        ? mode_a   : GL_REPLACE;
 263 }
 264
 265
 266
 267
 268 /* GL_ARB_multitexture */
 269 void GLAPIENTRY
 270 _mesa_ActiveTextureARB(GLenum texture)
 271 {
 272    GET_CURRENT_CONTEXT(ctx);
 273    const GLuint texUnit = texture - GL_TEXTURE0;
 274    ASSERT_OUTSIDE_BEGIN_END(ctx);
 275
 276    if (MESA_VERBOSE & (VERBOSE_API|VERBOSE_TEXTURE))
 277       _mesa_debug(ctx, "glActiveTexture %s\n",
 278                   _mesa_lookup_enum_by_nr(texture));
 279
 280    if (texUnit >= ctx->Const.MaxTextureImageUnits) {
 281       _mesa_error(ctx, GL_INVALID_ENUM, "glActiveTexture(texture)");
 282       return;
 283    }
 284
 285    if (ctx->Texture.CurrentUnit == texUnit)
 286       return;
 287
 288    FLUSH_VERTICES(ctx, _NEW_TEXTURE);
 289
 290    ctx->Texture.CurrentUnit = texUnit;
 291    if (ctx->Transform.MatrixMode == GL_TEXTURE) {
 292       /* update current stack pointer */
 293       ctx->CurrentStack = &ctx->TextureMatrixStack[texUnit];
 294    }
 295
 296    if (ctx->Driver.ActiveTexture) {
 297       (*ctx->Driver.ActiveTexture)( ctx, (GLuint) texUnit );
 298    }
 299 }
 300
 301
 302 /* GL_ARB_multitexture */
 303 void GLAPIENTRY
 304 _mesa_ClientActiveTextureARB(GLenum texture)
 305 {
 306    GET_CURRENT_CONTEXT(ctx);
 307    GLuint texUnit = texture - GL_TEXTURE0;
 308    ASSERT_OUTSIDE_BEGIN_END(ctx);
 309
 310    if (texUnit >= ctx->Const.MaxTextureCoordUnits) {
 311       _mesa_error(ctx, GL_INVALID_ENUM, "glClientActiveTexture(texture)");
 312       return;
 313    }
 314
 315    FLUSH_VERTICES(ctx, _NEW_ARRAY);
 316    ctx->Array.ActiveTexture = texUnit;
 317 }
 318
 319
 320
 321 /**********************************************************************/
 322 /*****                    State management                        *****/
 323 /**********************************************************************/
 324
 325
 326 /**
 327  * \note This routine refers to derived texture attribute values to
 328  * compute the ENABLE_TEXMAT flags, but is only called on
 329  * _NEW_TEXTURE_MATRIX.  On changes to _NEW_TEXTURE, the ENABLE_TEXMAT
 330  * flags are updated by _mesa_update_textures(), below.
 331  *
 332  * \param ctx GL context.
 333  */
 334 static void
 335 update_texture_matrices( GLcontext *ctx )
 336 {
 337    GLuint u;
 338
 339    ctx->Texture._TexMatEnabled = 0x0;
 340
 341    for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
 342       if (_math_matrix_is_dirty(ctx->TextureMatrixStack[u].Top)) {
 343          _math_matrix_analyse( ctx->TextureMatrixStack[u].Top );
 344
 345          if (ctx->Texture.Unit[u]._ReallyEnabled &&
 346              ctx->TextureMatrixStack[u].Top->type != MATRIX_IDENTITY)
 347             ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(u);
 348
 349          if (ctx->Driver.TextureMatrix)
 350             ctx->Driver.TextureMatrix( ctx, u, ctx->TextureMatrixStack[u].Top);
 351       }
 352    }
 353 }
 354
 355
 356 /**
 357  * Update texture object's _Function field.  We need to do this
 358  * whenever any of the texture object's shadow-related fields change
 359  * or when we start/stop using a fragment program.
 360  *
 361  * This function could be expanded someday to update additional per-object
 362  * fields that depend on assorted state changes.
 363  */
 364 static void
 365 update_texture_compare_function(GLcontext *ctx,
 366                                 struct gl_texture_object *tObj)
 367 {
 368    /* XXX temporarily disable this test since it breaks the GLSL
 369     * shadow2D(), etc. functions.
 370     */
 371    if (0 /*ctx->FragmentProgram._Current*/) {
 372       /* Texel/coordinate comparison is ignored for programs.
 373        * See GL_ARB_fragment_program/shader spec for details.
 374        */
 375       tObj->_Function = GL_NONE;
 376    }
 377    else if (tObj->CompareMode == GL_COMPARE_R_TO_TEXTURE_ARB) {
 378       /* GL_ARB_shadow */
 379       tObj->_Function = tObj->CompareFunc;
 380    }
 381    else {
 382       tObj->_Function = GL_NONE;  /* pass depth through as grayscale */
 383    }
 384 }
 385
 386
 387 /**
 388  * Examine texture unit's combine/env state to update derived state.
 389  */
 390 static void
 391 update_tex_combine(GLcontext *ctx, struct gl_texture_unit *texUnit)
 392 {
 393    struct gl_tex_env_combine_state *combine;
 394
 395    /* Set the texUnit->_CurrentCombine field to point to the user's combiner
 396     * state, or the combiner state which is derived from traditional texenv
 397     * mode.
 398     */
 399    if (texUnit->EnvMode == GL_COMBINE ||
 400        texUnit->EnvMode == GL_COMBINE4_NV) {
 401       texUnit->_CurrentCombine = & texUnit->Combine;
 402    }
 403    else {
 404       const struct gl_texture_object *texObj = texUnit->_Current;
 405       GLenum format = texObj->Image[0][texObj->BaseLevel]->_BaseFormat;
 406       if (format == GL_COLOR_INDEX) {
 407          format = GL_RGBA;  /* a bit of a hack */
 408       }
 409       else if (format == GL_DEPTH_COMPONENT ||
 410                format == GL_DEPTH_STENCIL_EXT) {
 411          format = texObj->DepthMode;
 412       }
 413       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 414       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 415    }
 416
 417    combine = texUnit->_CurrentCombine;
 418
 419    /* Determine number of source RGB terms in the combiner function */
 420    switch (combine->ModeRGB) {
 421    case GL_REPLACE:
 422       combine->_NumArgsRGB = 1;
 423       break;
 424    case GL_ADD:
 425    case GL_ADD_SIGNED:
 426       if (texUnit->EnvMode == GL_COMBINE4_NV)
 427          combine->_NumArgsRGB = 4;
 428       else
 429          combine->_NumArgsRGB = 2;
 430       break;
 431    case GL_MODULATE:
 432    case GL_SUBTRACT:
 433    case GL_DOT3_RGB:
 434    case GL_DOT3_RGBA:
 435    case GL_DOT3_RGB_EXT:
 436    case GL_DOT3_RGBA_EXT:
 437       combine->_NumArgsRGB = 2;
 438       break;
 439    case GL_INTERPOLATE:
 440    case GL_MODULATE_ADD_ATI:
 441    case GL_MODULATE_SIGNED_ADD_ATI:
 442    case GL_MODULATE_SUBTRACT_ATI:
 443       combine->_NumArgsRGB = 3;
 444       break;
 445    default:
 446       combine->_NumArgsRGB = 0;
 447       _mesa_problem(ctx, "invalid RGB combine mode in update_texture_state");
 448       return;
 449    }
 450
 451    /* Determine number of source Alpha terms in the combiner function */
 452    switch (combine->ModeA) {
 453    case GL_REPLACE:
 454       combine->_NumArgsA = 1;
 455       break;
 456    case GL_ADD:
 457    case GL_ADD_SIGNED:
 458       if (texUnit->EnvMode == GL_COMBINE4_NV)
 459          combine->_NumArgsA = 4;
 460       else
 461          combine->_NumArgsA = 2;
 462       break;
 463    case GL_MODULATE:
 464    case GL_SUBTRACT:
 465       combine->_NumArgsA = 2;
 466       break;
 467    case GL_INTERPOLATE:
 468    case GL_MODULATE_ADD_ATI:
 469    case GL_MODULATE_SIGNED_ADD_ATI:
 470    case GL_MODULATE_SUBTRACT_ATI:
 471       combine->_NumArgsA = 3;
 472       break;
 473    default:
 474       combine->_NumArgsA = 0;
 475       _mesa_problem(ctx, "invalid Alpha combine mode in update_texture_state");
 476       break;
 477    }
 478 }
 479
 480
 481 /**
 482  * \note This routine refers to derived texture matrix values to
 483  * compute the ENABLE_TEXMAT flags, but is only called on
 484  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 485  * flags are updated by _mesa_update_texture_matrices, above.
 486  *
 487  * \param ctx GL context.
 488  */
 489 static void
 490 update_texture_state( GLcontext *ctx )
 491 {
 492    GLuint unit;
 493    struct gl_fragment_program *fprog = NULL;
 494    struct gl_vertex_program *vprog = NULL;
 495    GLbitfield enabledFragUnits = 0x0;
 496
 497    if (ctx->Shader.CurrentProgram &&
 498        ctx->Shader.CurrentProgram->LinkStatus) {
 499       fprog = ctx->Shader.CurrentProgram->FragmentProgram;
 500       vprog = ctx->Shader.CurrentProgram->VertexProgram;
 501    }
 502    else {
 503       if (ctx->FragmentProgram._Enabled) {
 504          fprog = ctx->FragmentProgram.Current;
 505       }
 506       if (ctx->VertexProgram._Enabled) {
 507          /* XXX enable this if/when non-shader vertex programs get
 508           * texture fetches:
 509          vprog = ctx->VertexProgram.Current;
 510          */
 511       }
 512    }
 513
 514    /* TODO: only set this if there are actual changes */
 515    ctx->NewState |= _NEW_TEXTURE;
 516
 517    ctx->Texture._EnabledUnits = 0x0;
 518    ctx->Texture._GenFlags = 0x0;
 519    ctx->Texture._TexMatEnabled = 0x0;
 520    ctx->Texture._TexGenEnabled = 0x0;
 521
 522    /*
 523     * Update texture unit state.
 524     */
 525    for (unit = 0; unit < ctx->Const.MaxTextureImageUnits; unit++) {
 526       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 527       GLbitfield enabledVertTargets = 0x0;
 528       GLbitfield enabledFragTargets = 0x0;
 529       GLbitfield enabledTargets = 0x0;
 530       GLuint texIndex;
 531
 532       /* Get the bitmask of texture target enables.
 533        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 534        * which texture targets are enabled (fixed function) or referenced
 535        * by a fragment shader/program.  When multiple flags are set, we'll
 536        * settle on the one with highest priority (see below).
 537        */
 538       if (vprog) {
 539          enabledVertTargets |= vprog->Base.TexturesUsed[unit];
 540       }
 541
 542       if (fprog) {
 543          enabledFragTargets |= fprog->Base.TexturesUsed[unit];
 544       }
 545       else {
 546          /* fixed-function fragment program */
 547          enabledFragTargets |= texUnit->Enabled;
 548       }
 549
 550       enabledTargets = enabledVertTargets | enabledFragTargets;
 551
 552       if (enabledTargets == 0x0) {
 553          /* neither vertex nor fragment processing uses this unit */
 554          continue;
 555       }
 556
 557       texUnit->_Current = NULL;
 558       texUnit->_ReallyEnabled = 0x0;
 559
 560       /* Look for the highest priority texture target that's enabled (or used
 561        * by the vert/frag shaders) and "complete".  That's the one we'll use
 562        * for texturing.  If we're using vert/frag program we're guaranteed
 563        * that bitcount(enabledBits) <= 1.
 564        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 565        */
 566       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 567          if (enabledTargets & (1 << texIndex)) {
 568             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 569             if (!texObj->_Complete) {
 570                _mesa_test_texobj_completeness(ctx, texObj);
 571             }
 572             if (texObj->_Complete) {
 573                texUnit->_ReallyEnabled = 1 << texIndex;
 574                texUnit->_Current = texObj;
 575                break;
 576             }
 577          }
 578       }
 579
 580       if (texUnit->_Current)
 581          update_texture_compare_function(ctx, texUnit->_Current);
 582
 583       if (!texUnit->_ReallyEnabled) {
 584          continue;
 585       }
 586
 587       /* if we get here, we know this texture unit is enabled */
 588
 589       ctx->Texture._EnabledUnits |= (1 << unit);
 590
 591       if (enabledFragTargets)
 592          enabledFragUnits |= (1 << unit);
 593
 594       update_tex_combine(ctx, texUnit);
 595    }
 596
 597
 598    /* Determine which texture coordinate sets are actually needed */
 599    if (fprog) {
 600       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 601       ctx->Texture._EnabledCoordUnits
 602          = (fprog->Base.InputsRead >> FRAG_ATTRIB_TEX0) & coordMask;
 603    }
 604    else {
 605       ctx->Texture._EnabledCoordUnits = enabledFragUnits;
 606    }
 607
 608    /* Setup texgen for those texture coordinate sets that are in use */
 609    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 610       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 611
 612       texUnit->_GenFlags = 0x0;
 613
 614       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 615          continue;
 616
 617       if (texUnit->TexGenEnabled) {
 618          if (texUnit->TexGenEnabled & S_BIT) {
 619             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 620          }
 621          if (texUnit->TexGenEnabled & T_BIT) {
 622             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 623          }
 624          if (texUnit->TexGenEnabled & R_BIT) {
 625             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 626          }
 627          if (texUnit->TexGenEnabled & Q_BIT) {
 628             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 629          }
 630
 631          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 632          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 633       }
 634
 635       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 636          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 637    }
 638 }
 639
 640
 641 /**
 642  * Update texture-related derived state.
 643  */
 644 void
 645 _mesa_update_texture( GLcontext *ctx, GLuint new_state )
 646 {
 647    if (new_state & _NEW_TEXTURE_MATRIX)
 648       update_texture_matrices( ctx );
 649
 650    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 651       update_texture_state( ctx );
 652 }
 653
 654
 655 /**********************************************************************/
 656 /*****                      Initialization                        *****/
 657 /**********************************************************************/
 658
 659 /**
 660  * Allocate the proxy textures for the given context.
 661  *
 662  * \param ctx the context to allocate proxies for.
 663  *
 664  * \return GL_TRUE on success, or GL_FALSE on failure
 665  *
 666  * If run out of memory part way through the allocations, clean up and return
 667  * GL_FALSE.
 668  */
 669 static GLboolean
 670 alloc_proxy_textures( GLcontext *ctx )
 671 {
 672    static const GLenum targets[] = {
 673       GL_TEXTURE_1D,
 674       GL_TEXTURE_2D,
 675       GL_TEXTURE_3D,
 676       GL_TEXTURE_CUBE_MAP_ARB,
 677       GL_TEXTURE_RECTANGLE_NV,
 678       GL_TEXTURE_1D_ARRAY_EXT,
 679       GL_TEXTURE_2D_ARRAY_EXT
 680    };
 681    GLint tgt;
 682
 683    ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 684
 685    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 686       if (!(ctx->Texture.ProxyTex[tgt]
 687             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 688          /* out of memory, free what we did allocate */
 689          while (--tgt >= 0) {
 690             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 691          }
 692          return GL_FALSE;
 693       }
 694    }
 695
 696    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 697    return GL_TRUE;
 698 }
 699
 700
 701 /**
 702  * Initialize a texture unit.
 703  *
 704  * \param ctx GL context.
 705  * \param unit texture unit number to be initialized.
 706  */
 707 static void
 708 init_texture_unit( GLcontext *ctx, GLuint unit )
 709 {
 710    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 711    GLuint tex;
 712
 713    texUnit->EnvMode = GL_MODULATE;
 714    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 715
 716    texUnit->Combine = default_combine_state;
 717    texUnit->_EnvMode = default_combine_state;
 718    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 719
 720    texUnit->TexGenEnabled = 0x0;
 721    texUnit->GenS.Mode = GL_EYE_LINEAR;
 722    texUnit->GenT.Mode = GL_EYE_LINEAR;
 723    texUnit->GenR.Mode = GL_EYE_LINEAR;
 724    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 725    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 726    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 727    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 728    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 729
 730    /* Yes, these plane coefficients are correct! */
 731    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 732    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 733    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 734    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 735    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 736    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 737    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 738    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 739
 740    /* initialize current texture object ptrs to the shared default objects */
 741    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 742       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 743                              ctx->Shared->DefaultTex[tex]);
 744    }
 745 }
 746
 747
 748 /**
 749  * Initialize texture state for the given context.
 750  */
 751 GLboolean
 752 _mesa_init_texture(GLcontext *ctx)
 753 {
 754    GLuint u;
 755
 756    /* Texture group */
 757    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 758    ctx->Texture._EnabledUnits = 0x0;
 759    ctx->Texture.SharedPalette = GL_FALSE;
 760 #if FEATURE_colortable
 761    _mesa_init_colortable(&ctx->Texture.Palette);
 762 #endif
 763
 764    for (u = 0; u < MAX_TEXTURE_UNITS; u++)
 765       init_texture_unit(ctx, u);
 766
 767    /* After we're done initializing the context's texture state the default
 768     * texture objects' refcounts should be at least MAX_TEXTURE_UNITS + 1.
 769     */
 770    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 771           >= MAX_TEXTURE_UNITS + 1);
 772
 773    /* Allocate proxy textures */
 774    if (!alloc_proxy_textures( ctx ))
 775       return GL_FALSE;
 776
 777    return GL_TRUE;
 778 }
 779
 780
 781 /**
 782  * Free dynamically-allocted texture data attached to the given context.
 783  */
 784 void
 785 _mesa_free_texture_data(GLcontext *ctx)
 786 {
 787    GLuint u, tgt;
 788
 789    /* unreference current textures */
 790    for (u = 0; u < MAX_TEXTURE_IMAGE_UNITS; u++) {
 791       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 792          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 793       }
 794    }
 795
 796    /* Free proxy texture objects */
 797    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 798       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 799
 800 #if FEATURE_colortable
 801    for (u = 0; u < MAX_TEXTURE_IMAGE_UNITS; u++)
 802       _mesa_free_colortable_data(&ctx->Texture.Unit[u].ColorTable);
 803 #endif
 804 }
 805
 806
 807 /**
 808  * Update the default texture objects in the given context to reference those
 809  * specified in the shared state and release those referencing the old
 810  * shared state.
 811  */
 812 void
 813 _mesa_update_default_objects_texture(GLcontext *ctx)
 814 {
 815    GLuint u, tex;
 816
 817    for (u = 0; u < MAX_TEXTURE_UNITS; u++) {
 818       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 819       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 820          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 821                                 ctx->Shared->DefaultTex[tex]);
 822       }
 823    }
 824 }