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