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  * Helper function for determining which texture object (1D, 2D, cube, etc)
 389  * should actually be used.
 390  */
 391 static void
 392 texture_override(GLcontext *ctx,
 393                  struct gl_texture_unit *texUnit, GLbitfield enableBits,
 394                  struct gl_texture_object *texObj, GLuint textureBit)
 395 {
 396    if (!texUnit->_ReallyEnabled && (enableBits & textureBit)) {
 397       if (!texObj->_Complete) {
 398          _mesa_test_texobj_completeness(ctx, texObj);
 399       }
 400       if (texObj->_Complete) {
 401          texUnit->_ReallyEnabled = textureBit;
 402          texUnit->_Current = texObj;
 403          update_texture_compare_function(ctx, texObj);
 404       }
 405    }
 406 }
 407
 408
 409 /**
 410  * Examine texture unit's combine/env state to update derived state.
 411  */
 412 static void
 413 update_tex_combine(GLcontext *ctx, struct gl_texture_unit *texUnit)
 414 {
 415    struct gl_tex_env_combine_state *combine;
 416
 417    /* Set the texUnit->_CurrentCombine field to point to the user's combiner
 418     * state, or the combiner state which is derived from traditional texenv
 419     * mode.
 420     */
 421    if (texUnit->EnvMode == GL_COMBINE ||
 422        texUnit->EnvMode == GL_COMBINE4_NV) {
 423       texUnit->_CurrentCombine = & texUnit->Combine;
 424    }
 425    else {
 426       const struct gl_texture_object *texObj = texUnit->_Current;
 427       GLenum format = texObj->Image[0][texObj->BaseLevel]->_BaseFormat;
 428       if (format == GL_COLOR_INDEX) {
 429          format = GL_RGBA;  /* a bit of a hack */
 430       }
 431       else if (format == GL_DEPTH_COMPONENT ||
 432                format == GL_DEPTH_STENCIL_EXT) {
 433          format = texObj->DepthMode;
 434       }
 435       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 436       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 437    }
 438
 439    combine = texUnit->_CurrentCombine;
 440
 441    /* Determine number of source RGB terms in the combiner function */
 442    switch (combine->ModeRGB) {
 443    case GL_REPLACE:
 444       combine->_NumArgsRGB = 1;
 445       break;
 446    case GL_ADD:
 447    case GL_ADD_SIGNED:
 448       if (texUnit->EnvMode == GL_COMBINE4_NV)
 449          combine->_NumArgsRGB = 4;
 450       else
 451          combine->_NumArgsRGB = 2;
 452       break;
 453    case GL_MODULATE:
 454    case GL_SUBTRACT:
 455    case GL_DOT3_RGB:
 456    case GL_DOT3_RGBA:
 457    case GL_DOT3_RGB_EXT:
 458    case GL_DOT3_RGBA_EXT:
 459       combine->_NumArgsRGB = 2;
 460       break;
 461    case GL_INTERPOLATE:
 462    case GL_MODULATE_ADD_ATI:
 463    case GL_MODULATE_SIGNED_ADD_ATI:
 464    case GL_MODULATE_SUBTRACT_ATI:
 465       combine->_NumArgsRGB = 3;
 466       break;
 467    default:
 468       combine->_NumArgsRGB = 0;
 469       _mesa_problem(ctx, "invalid RGB combine mode in update_texture_state");
 470       return;
 471    }
 472
 473    /* Determine number of source Alpha terms in the combiner function */
 474    switch (combine->ModeA) {
 475    case GL_REPLACE:
 476       combine->_NumArgsA = 1;
 477       break;
 478    case GL_ADD:
 479    case GL_ADD_SIGNED:
 480       if (texUnit->EnvMode == GL_COMBINE4_NV)
 481          combine->_NumArgsA = 4;
 482       else
 483          combine->_NumArgsA = 2;
 484       break;
 485    case GL_MODULATE:
 486    case GL_SUBTRACT:
 487       combine->_NumArgsA = 2;
 488       break;
 489    case GL_INTERPOLATE:
 490    case GL_MODULATE_ADD_ATI:
 491    case GL_MODULATE_SIGNED_ADD_ATI:
 492    case GL_MODULATE_SUBTRACT_ATI:
 493       combine->_NumArgsA = 3;
 494       break;
 495    default:
 496       combine->_NumArgsA = 0;
 497       _mesa_problem(ctx, "invalid Alpha combine mode in update_texture_state");
 498       break;
 499    }
 500 }
 501
 502
 503 /**
 504  * \note This routine refers to derived texture matrix values to
 505  * compute the ENABLE_TEXMAT flags, but is only called on
 506  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 507  * flags are updated by _mesa_update_texture_matrices, above.
 508  *
 509  * \param ctx GL context.
 510  */
 511 static void
 512 update_texture_state( GLcontext *ctx )
 513 {
 514    GLuint unit;
 515    struct gl_fragment_program *fprog = NULL;
 516    struct gl_vertex_program *vprog = NULL;
 517
 518    if (ctx->Shader.CurrentProgram &&
 519        ctx->Shader.CurrentProgram->LinkStatus) {
 520       fprog = ctx->Shader.CurrentProgram->FragmentProgram;
 521       vprog = ctx->Shader.CurrentProgram->VertexProgram;
 522    }
 523    else {
 524       if (ctx->FragmentProgram._Enabled) {
 525          fprog = ctx->FragmentProgram.Current;
 526       }
 527       if (ctx->VertexProgram._Enabled) {
 528          /* XXX enable this if/when non-shader vertex programs get
 529           * texture fetches:
 530          vprog = ctx->VertexProgram.Current;
 531          */
 532       }
 533    }
 534
 535    /* TODO: only set this if there are actual changes */
 536    ctx->NewState |= _NEW_TEXTURE;
 537
 538    ctx->Texture._EnabledUnits = 0x0;
 539    ctx->Texture._GenFlags = 0x0;
 540    ctx->Texture._TexMatEnabled = 0x0;
 541    ctx->Texture._TexGenEnabled = 0x0;
 542
 543    /*
 544     * Update texture unit state.
 545     */
 546    for (unit = 0; unit < ctx->Const.MaxTextureImageUnits; unit++) {
 547       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 548       GLbitfield enableBits;
 549       GLuint texIndex;
 550
 551       texUnit->_Current = NULL;
 552       texUnit->_ReallyEnabled = 0x0;
 553
 554       /* Get the bitmask of texture target enables.
 555        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 556        * which texture targets are enabled (fixed function) or referenced
 557        * by a fragment shader/program.  When multiple flags are set, we'll
 558        * settle on the one with highest priority (see texture_override below).
 559        */
 560       enableBits = 0x0;
 561       if (vprog) {
 562          enableBits |= vprog->Base.TexturesUsed[unit];
 563       }
 564       if (fprog) {
 565          enableBits |= fprog->Base.TexturesUsed[unit];
 566       }
 567       else {
 568          /* fixed-function fragment program */
 569          enableBits |= texUnit->Enabled;
 570       }
 571
 572       if (enableBits == 0x0)
 573          continue;
 574
 575       /* Look for the highest-priority texture target that's enabled and
 576        * complete.  That's the one we'll use for texturing.  If we're using
 577        * a fragment program we're guaranteed that bitcount(enabledBits) <= 1.
 578        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 579        */
 580       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 581          texture_override(ctx, texUnit, enableBits,
 582                           texUnit->CurrentTex[texIndex], 1 << texIndex);
 583       }
 584
 585       if (!texUnit->_ReallyEnabled) {
 586          continue;
 587       }
 588
 589       /* if we get here, we know this texture unit is enabled */
 590
 591       ctx->Texture._EnabledUnits |= (1 << unit);
 592
 593       update_tex_combine(ctx, texUnit);
 594    }
 595
 596
 597    /* Determine which texture coordinate sets are actually needed */
 598    if (fprog) {
 599       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 600       ctx->Texture._EnabledCoordUnits
 601          = (fprog->Base.InputsRead >> FRAG_ATTRIB_TEX0) & coordMask;
 602    }
 603    else {
 604       ctx->Texture._EnabledCoordUnits = ctx->Texture._EnabledUnits;
 605    }
 606
 607    /* Setup texgen for those texture coordinate sets that are in use */
 608    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 609       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 610
 611       texUnit->_GenFlags = 0x0;
 612
 613       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 614          continue;
 615
 616       if (texUnit->TexGenEnabled) {
 617          if (texUnit->TexGenEnabled & S_BIT) {
 618             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 619          }
 620          if (texUnit->TexGenEnabled & T_BIT) {
 621             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 622          }
 623          if (texUnit->TexGenEnabled & R_BIT) {
 624             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 625          }
 626          if (texUnit->TexGenEnabled & Q_BIT) {
 627             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 628          }
 629
 630          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 631          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 632       }
 633
 634       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 635          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 636    }
 637 }
 638
 639
 640 /**
 641  * Update texture-related derived state.
 642  */
 643 void
 644 _mesa_update_texture( GLcontext *ctx, GLuint new_state )
 645 {
 646    if (new_state & _NEW_TEXTURE_MATRIX)
 647       update_texture_matrices( ctx );
 648
 649    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 650       update_texture_state( ctx );
 651 }
 652
 653
 654 /**********************************************************************/
 655 /*****                      Initialization                        *****/
 656 /**********************************************************************/
 657
 658 /**
 659  * Allocate the proxy textures for the given context.
 660  *
 661  * \param ctx the context to allocate proxies for.
 662  *
 663  * \return GL_TRUE on success, or GL_FALSE on failure
 664  *
 665  * If run out of memory part way through the allocations, clean up and return
 666  * GL_FALSE.
 667  */
 668 static GLboolean
 669 alloc_proxy_textures( GLcontext *ctx )
 670 {
 671    static const GLenum targets[] = {
 672       GL_TEXTURE_1D,
 673       GL_TEXTURE_2D,
 674       GL_TEXTURE_3D,
 675       GL_TEXTURE_CUBE_MAP_ARB,
 676       GL_TEXTURE_RECTANGLE_NV,
 677       GL_TEXTURE_1D_ARRAY_EXT,
 678       GL_TEXTURE_2D_ARRAY_EXT
 679    };
 680    GLint tgt;
 681
 682    ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 683
 684    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 685       if (!(ctx->Texture.ProxyTex[tgt]
 686             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 687          /* out of memory, free what we did allocate */
 688          while (--tgt >= 0) {
 689             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 690          }
 691          return GL_FALSE;
 692       }
 693    }
 694
 695    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 696    return GL_TRUE;
 697 }
 698
 699
 700 /**
 701  * Initialize a texture unit.
 702  *
 703  * \param ctx GL context.
 704  * \param unit texture unit number to be initialized.
 705  */
 706 static void
 707 init_texture_unit( GLcontext *ctx, GLuint unit )
 708 {
 709    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 710    GLuint tex;
 711
 712    texUnit->EnvMode = GL_MODULATE;
 713    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 714
 715    texUnit->Combine = default_combine_state;
 716    texUnit->_EnvMode = default_combine_state;
 717    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 718
 719    texUnit->TexGenEnabled = 0x0;
 720    texUnit->GenS.Mode = GL_EYE_LINEAR;
 721    texUnit->GenT.Mode = GL_EYE_LINEAR;
 722    texUnit->GenR.Mode = GL_EYE_LINEAR;
 723    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 724    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 725    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 726    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 727    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 728
 729    /* Yes, these plane coefficients are correct! */
 730    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 731    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 732    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 733    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 734    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 735    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 736    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 737    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 738
 739    /* initialize current texture object ptrs to the shared default objects */
 740    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 741       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 742                              ctx->Shared->DefaultTex[tex]);
 743    }
 744 }
 745
 746
 747 /**
 748  * Initialize texture state for the given context.
 749  */
 750 GLboolean
 751 _mesa_init_texture(GLcontext *ctx)
 752 {
 753    GLuint u;
 754
 755    /* Texture group */
 756    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 757    ctx->Texture._EnabledUnits = 0x0;
 758    ctx->Texture.SharedPalette = GL_FALSE;
 759 #if FEATURE_colortable
 760    _mesa_init_colortable(&ctx->Texture.Palette);
 761 #endif
 762
 763    for (u = 0; u < MAX_TEXTURE_UNITS; u++)
 764       init_texture_unit(ctx, u);
 765
 766    /* After we're done initializing the context's texture state the default
 767     * texture objects' refcounts should be at least MAX_TEXTURE_UNITS + 1.
 768     */
 769    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 770           >= MAX_TEXTURE_UNITS + 1);
 771
 772    /* Allocate proxy textures */
 773    if (!alloc_proxy_textures( ctx ))
 774       return GL_FALSE;
 775
 776    return GL_TRUE;
 777 }
 778
 779
 780 /**
 781  * Free dynamically-allocted texture data attached to the given context.
 782  */
 783 void
 784 _mesa_free_texture_data(GLcontext *ctx)
 785 {
 786    GLuint u, tgt;
 787
 788    /* unreference current textures */
 789    for (u = 0; u < MAX_TEXTURE_IMAGE_UNITS; u++) {
 790       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 791          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 792       }
 793    }
 794
 795    /* Free proxy texture objects */
 796    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 797       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 798
 799 #if FEATURE_colortable
 800    for (u = 0; u < MAX_TEXTURE_IMAGE_UNITS; u++)
 801       _mesa_free_colortable_data(&ctx->Texture.Unit[u].ColorTable);
 802 #endif
 803 }
 804
 805
 806 /**
 807  * Update the default texture objects in the given context to reference those
 808  * specified in the shared state and release those referencing the old
 809  * shared state.
 810  */
 811 void
 812 _mesa_update_default_objects_texture(GLcontext *ctx)
 813 {
 814    GLuint u, tex;
 815
 816    for (u = 0; u < MAX_TEXTURE_UNITS; u++) {
 817       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 818       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 819          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 820                                 ctx->Shared->DefaultTex[tex]);
 821       }
 822    }
 823 }