reactos/dll/opengl/mesa/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 "bufferobj.h"
  34 #include "colormac.h"
  35 #include "colortab.h"
  36 #include "context.h"
  37 #include "enums.h"
  38 #include "macros.h"
  39 #include "texobj.h"
  40 #include "teximage.h"
  41 #include "texstate.h"
  42 #include "mtypes.h"
  43
  44
  45
  46 /**
  47  * Default texture combine environment state.  This is used to initialize
  48  * a context's texture units and as the basis for converting "classic"
  49  * texture environmnets to ARB_texture_env_combine style values.
  50  */
  51 static const struct gl_tex_env_combine_state default_combine_state = {
  52    GL_MODULATE, GL_MODULATE,
  53    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  54    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  55    { GL_SRC_COLOR, GL_SRC_COLOR, GL_SRC_ALPHA, GL_SRC_ALPHA },
  56    { GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA },
  57    0, 0,
  58    2, 2
  59 };
  60
  61
  62
  63 /**
  64  * Used by glXCopyContext to copy texture state from one context to another.
  65  */
  66 void
  67 _mesa_copy_texture_state( const struct gl_context *src, struct gl_context *dst )
  68 {
  69    GLuint u, tex;
  70
  71    ASSERT(src);
  72    ASSERT(dst);
  73
  74    dst->Texture.CurrentUnit = src->Texture.CurrentUnit;
  75    dst->Texture._GenFlags = src->Texture._GenFlags;
  76    dst->Texture._TexGenEnabled = src->Texture._TexGenEnabled;
  77    dst->Texture._TexMatEnabled = src->Texture._TexMatEnabled;
  78
  79    /* per-unit state */
  80    for (u = 0; u < src->Const.MaxCombinedTextureImageUnits; 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( struct gl_context *ctx, GLuint unit )
 123 {
 124    const struct gl_texture_unit *texUnit = ctx->Texture.Unit + unit;
 125    printf("Texture Unit %d\n", unit);
 126    printf("  GL_TEXTURE_ENV_MODE = %s\n", _mesa_lookup_enum_by_nr(texUnit->EnvMode));
 127    printf("  GL_COMBINE_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeRGB));
 128    printf("  GL_COMBINE_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeA));
 129    printf("  GL_SOURCE0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[0]));
 130    printf("  GL_SOURCE1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[1]));
 131    printf("  GL_SOURCE2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[2]));
 132    printf("  GL_SOURCE0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[0]));
 133    printf("  GL_SOURCE1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[1]));
 134    printf("  GL_SOURCE2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[2]));
 135    printf("  GL_OPERAND0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[0]));
 136    printf("  GL_OPERAND1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[1]));
 137    printf("  GL_OPERAND2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[2]));
 138    printf("  GL_OPERAND0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[0]));
 139    printf("  GL_OPERAND1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[1]));
 140    printf("  GL_OPERAND2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[2]));
 141    printf("  GL_RGB_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftRGB);
 142    printf("  GL_ALPHA_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftA);
 143    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_RED:
 183    case GL_RG:
 184    case GL_RGB:
 185    case GL_YCBCR_MESA:
 186    case GL_DUDV_ATI:
 187       state->SourceA[0] = GL_PREVIOUS;
 188       break;
 189
 190    default:
 191       _mesa_problem(NULL,
 192                     "Invalid texBaseFormat 0x%x in calculate_derived_texenv",
 193                     texBaseFormat);
 194       return;
 195    }
 196
 197    if (mode == GL_REPLACE_EXT)
 198       mode = GL_REPLACE;
 199
 200    switch (mode) {
 201    case GL_REPLACE:
 202    case GL_MODULATE:
 203       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : mode;
 204       mode_a   = mode;
 205       break;
 206
 207    case GL_DECAL:
 208       mode_rgb = GL_INTERPOLATE;
 209       mode_a   = GL_REPLACE;
 210
 211       state->SourceA[0] = GL_PREVIOUS;
 212
 213       /* Having alpha / luminance / intensity textures replace using the
 214        * incoming fragment color matches the definition in NV_texture_shader.
 215        * The 1.5 spec simply marks these as "undefined".
 216        */
 217       switch (texBaseFormat) {
 218       case GL_ALPHA:
 219       case GL_LUMINANCE:
 220       case GL_LUMINANCE_ALPHA:
 221       case GL_INTENSITY:
 222          state->SourceRGB[0] = GL_PREVIOUS;
 223          break;
 224       case GL_RED:
 225       case GL_RG:
 226       case GL_RGB:
 227       case GL_YCBCR_MESA:
 228       case GL_DUDV_ATI:
 229          mode_rgb = GL_REPLACE;
 230          break;
 231       case GL_RGBA:
 232          state->SourceRGB[2] = GL_TEXTURE;
 233          break;
 234       }
 235       break;
 236
 237    case GL_BLEND:
 238       mode_rgb = GL_INTERPOLATE;
 239       mode_a   = GL_MODULATE;
 240
 241       switch (texBaseFormat) {
 242       case GL_ALPHA:
 243          mode_rgb = GL_REPLACE;
 244          break;
 245       case GL_INTENSITY:
 246          mode_a = GL_INTERPOLATE;
 247          state->SourceA[0] = GL_CONSTANT;
 248          state->OperandA[2] = GL_SRC_ALPHA;
 249          /* FALLTHROUGH */
 250       case GL_LUMINANCE:
 251       case GL_RED:
 252       case GL_RG:
 253       case GL_RGB:
 254       case GL_LUMINANCE_ALPHA:
 255       case GL_RGBA:
 256       case GL_YCBCR_MESA:
 257       case GL_DUDV_ATI:
 258          state->SourceRGB[2] = GL_TEXTURE;
 259          state->SourceA[2]   = GL_TEXTURE;
 260          state->SourceRGB[0] = GL_CONSTANT;
 261          state->OperandRGB[2] = GL_SRC_COLOR;
 262          break;
 263       }
 264       break;
 265
 266    case GL_ADD:
 267       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : GL_ADD;
 268       mode_a   = (texBaseFormat == GL_INTENSITY) ? GL_ADD : GL_MODULATE;
 269       break;
 270
 271    default:
 272       _mesa_problem(NULL,
 273                     "Invalid texture env mode 0x%x in calculate_derived_texenv",
 274                     mode);
 275       return;
 276    }
 277
 278    state->ModeRGB = (state->SourceRGB[0] != GL_PREVIOUS)
 279        ? mode_rgb : GL_REPLACE;
 280    state->ModeA   = (state->SourceA[0]   != GL_PREVIOUS)
 281        ? mode_a   : GL_REPLACE;
 282 }
 283
 284
 285
 286
 287 /* GL_ARB_multitexture */
 288 void GLAPIENTRY
 289 _mesa_ActiveTextureARB(GLenum texture)
 290 {
 291    const GLuint texUnit = texture - GL_TEXTURE0;
 292    GLuint k;
 293    GET_CURRENT_CONTEXT(ctx);
 294
 295    /* See OpenGL spec for glActiveTexture: */
 296    k = MAX2(ctx->Const.MaxCombinedTextureImageUnits,
 297             ctx->Const.MaxTextureCoordUnits);
 298
 299    ASSERT(k <= Elements(ctx->Texture.Unit));
 300
 301    ASSERT_OUTSIDE_BEGIN_END(ctx);
 302
 303    if (MESA_VERBOSE & (VERBOSE_API|VERBOSE_TEXTURE))
 304       _mesa_debug(ctx, "glActiveTexture %s\n",
 305                   _mesa_lookup_enum_by_nr(texture));
 306
 307    if (texUnit >= k) {
 308       _mesa_error(ctx, GL_INVALID_ENUM, "glActiveTexture(texture=%s)",
 309                   _mesa_lookup_enum_by_nr(texture));
 310       return;
 311    }
 312
 313    if (ctx->Texture.CurrentUnit == texUnit)
 314       return;
 315
 316    FLUSH_VERTICES(ctx, _NEW_TEXTURE);
 317
 318    ctx->Texture.CurrentUnit = texUnit;
 319    if (ctx->Transform.MatrixMode == GL_TEXTURE) {
 320       /* update current stack pointer */
 321       ctx->CurrentStack = &ctx->TextureMatrixStack[texUnit];
 322    }
 323 }
 324
 325
 326 /* GL_ARB_multitexture */
 327 void GLAPIENTRY
 328 _mesa_ClientActiveTextureARB(GLenum texture)
 329 {
 330    GET_CURRENT_CONTEXT(ctx);
 331    GLuint texUnit = texture - GL_TEXTURE0;
 332    ASSERT_OUTSIDE_BEGIN_END(ctx);
 333
 334    if (MESA_VERBOSE & (VERBOSE_API | VERBOSE_TEXTURE))
 335       _mesa_debug(ctx, "glClientActiveTexture %s\n",
 336                   _mesa_lookup_enum_by_nr(texture));
 337
 338    if (texUnit >= ctx->Const.MaxTextureCoordUnits) {
 339       _mesa_error(ctx, GL_INVALID_ENUM, "glClientActiveTexture(texture)");
 340       return;
 341    }
 342
 343    if (ctx->Array.ActiveTexture == texUnit)
 344       return;
 345
 346    FLUSH_VERTICES(ctx, _NEW_ARRAY);
 347    ctx->Array.ActiveTexture = texUnit;
 348 }
 349
 350
 351
 352 /**********************************************************************/
 353 /*****                    State management                        *****/
 354 /**********************************************************************/
 355
 356
 357 /**
 358  * \note This routine refers to derived texture attribute values to
 359  * compute the ENABLE_TEXMAT flags, but is only called on
 360  * _NEW_TEXTURE_MATRIX.  On changes to _NEW_TEXTURE, the ENABLE_TEXMAT
 361  * flags are updated by _mesa_update_textures(), below.
 362  *
 363  * \param ctx GL context.
 364  */
 365 static void
 366 update_texture_matrices( struct gl_context *ctx )
 367 {
 368    GLuint u;
 369
 370    ctx->Texture._TexMatEnabled = 0x0;
 371
 372    for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
 373       ASSERT(u < Elements(ctx->TextureMatrixStack));
 374       if (_math_matrix_is_dirty(ctx->TextureMatrixStack[u].Top)) {
 375          _math_matrix_analyse( ctx->TextureMatrixStack[u].Top );
 376
 377          if (ctx->Texture.Unit[u]._ReallyEnabled &&
 378              ctx->TextureMatrixStack[u].Top->type != MATRIX_IDENTITY)
 379             ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(u);
 380       }
 381    }
 382 }
 383
 384
 385 /**
 386  * Examine texture unit's combine/env state to update derived state.
 387  */
 388 static void
 389 update_tex_combine(struct gl_context *ctx, struct gl_texture_unit *texUnit)
 390 {
 391    struct gl_tex_env_combine_state *combine;
 392
 393    /* Set the texUnit->_CurrentCombine field to point to the user's combiner
 394     * state, or the combiner state which is derived from traditional texenv
 395     * mode.
 396     */
 397    if (texUnit->EnvMode == GL_COMBINE ||
 398        texUnit->EnvMode == GL_COMBINE4_NV) {
 399       texUnit->_CurrentCombine = & texUnit->Combine;
 400    }
 401    else {
 402       const struct gl_texture_object *texObj = texUnit->_Current;
 403       GLenum format = texObj->Image[0][texObj->BaseLevel]->_BaseFormat;
 404
 405       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 406       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 407    }
 408
 409    combine = texUnit->_CurrentCombine;
 410
 411    /* Determine number of source RGB terms in the combiner function */
 412    switch (combine->ModeRGB) {
 413    case GL_REPLACE:
 414       combine->_NumArgsRGB = 1;
 415       break;
 416    case GL_ADD:
 417    case GL_ADD_SIGNED:
 418       if (texUnit->EnvMode == GL_COMBINE4_NV)
 419          combine->_NumArgsRGB = 4;
 420       else
 421          combine->_NumArgsRGB = 2;
 422       break;
 423    case GL_MODULATE:
 424    case GL_SUBTRACT:
 425    case GL_DOT3_RGB:
 426    case GL_DOT3_RGBA:
 427    case GL_DOT3_RGB_EXT:
 428    case GL_DOT3_RGBA_EXT:
 429       combine->_NumArgsRGB = 2;
 430       break;
 431    case GL_INTERPOLATE:
 432    case GL_MODULATE_ADD_ATI:
 433    case GL_MODULATE_SIGNED_ADD_ATI:
 434    case GL_MODULATE_SUBTRACT_ATI:
 435       combine->_NumArgsRGB = 3;
 436       break;
 437    case GL_BUMP_ENVMAP_ATI:
 438       /* no real arguments for this case */
 439       combine->_NumArgsRGB = 0;
 440       break;
 441    default:
 442       combine->_NumArgsRGB = 0;
 443       _mesa_problem(ctx, "invalid RGB combine mode in update_texture_state");
 444       return;
 445    }
 446
 447    /* Determine number of source Alpha terms in the combiner function */
 448    switch (combine->ModeA) {
 449    case GL_REPLACE:
 450       combine->_NumArgsA = 1;
 451       break;
 452    case GL_ADD:
 453    case GL_ADD_SIGNED:
 454       if (texUnit->EnvMode == GL_COMBINE4_NV)
 455          combine->_NumArgsA = 4;
 456       else
 457          combine->_NumArgsA = 2;
 458       break;
 459    case GL_MODULATE:
 460    case GL_SUBTRACT:
 461       combine->_NumArgsA = 2;
 462       break;
 463    case GL_INTERPOLATE:
 464    case GL_MODULATE_ADD_ATI:
 465    case GL_MODULATE_SIGNED_ADD_ATI:
 466    case GL_MODULATE_SUBTRACT_ATI:
 467       combine->_NumArgsA = 3;
 468       break;
 469    default:
 470       combine->_NumArgsA = 0;
 471       _mesa_problem(ctx, "invalid Alpha combine mode in update_texture_state");
 472       break;
 473    }
 474 }
 475
 476
 477 /**
 478  * \note This routine refers to derived texture matrix values to
 479  * compute the ENABLE_TEXMAT flags, but is only called on
 480  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 481  * flags are updated by _mesa_update_texture_matrices, above.
 482  *
 483  * \param ctx GL context.
 484  */
 485 static void
 486 update_texture_state( struct gl_context *ctx )
 487 {
 488    GLuint unit;
 489    struct gl_program *fprog = NULL;
 490    struct gl_program *vprog = NULL;
 491    GLbitfield enabledFragUnits = 0x0;
 492
 493    if (ctx->Shader.CurrentVertexProgram &&
 494        ctx->Shader.CurrentVertexProgram->LinkStatus) {
 495       vprog = ctx->Shader.CurrentVertexProgram->_LinkedShaders[MESA_SHADER_VERTEX]->Program;
 496    } else if (ctx->VertexProgram._Enabled) {
 497       /* XXX enable this if/when non-shader vertex programs get
 498        * texture fetches:
 499        vprog = &ctx->VertexProgram.Current->Base;
 500        */
 501    }
 502
 503    if (ctx->Shader.CurrentFragmentProgram &&
 504        ctx->Shader.CurrentFragmentProgram->LinkStatus) {
 505       fprog = ctx->Shader.CurrentFragmentProgram->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program;
 506    }
 507    else if (ctx->FragmentProgram._Enabled) {
 508       fprog = &ctx->FragmentProgram.Current->Base;
 509    }
 510
 511    /* FINISHME: Geometry shader texture accesses should also be considered
 512     * FINISHME: here.
 513     */
 514
 515    /* TODO: only set this if there are actual changes */
 516    ctx->NewState |= _NEW_TEXTURE;
 517
 518    ctx->Texture._EnabledUnits = 0x0;
 519    ctx->Texture._GenFlags = 0x0;
 520    ctx->Texture._TexMatEnabled = 0x0;
 521    ctx->Texture._TexGenEnabled = 0x0;
 522
 523    /*
 524     * Update texture unit state.
 525     */
 526    for (unit = 0; unit < ctx->Const.MaxCombinedTextureImageUnits; unit++) {
 527       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 528       GLbitfield enabledVertTargets = 0x0;
 529       GLbitfield enabledFragTargets = 0x0;
 530       GLbitfield enabledTargets = 0x0;
 531       GLuint texIndex;
 532
 533       /* Get the bitmask of texture target enables.
 534        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 535        * which texture targets are enabled (fixed function) or referenced
 536        * by a fragment program/program.  When multiple flags are set, we'll
 537        * settle on the one with highest priority (see below).
 538        */
 539       if (vprog) {
 540          enabledVertTargets |= vprog->TexturesUsed[unit];
 541       }
 542
 543       if (fprog) {
 544          enabledFragTargets |= fprog->TexturesUsed[unit];
 545       }
 546       else {
 547          /* fixed-function fragment program */
 548          enabledFragTargets |= texUnit->Enabled;
 549       }
 550
 551       enabledTargets = enabledVertTargets | enabledFragTargets;
 552
 553       texUnit->_ReallyEnabled = 0x0;
 554
 555       if (enabledTargets == 0x0) {
 556          /* neither vertex nor fragment processing uses this unit */
 557          continue;
 558       }
 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                _mesa_reference_texobj(&texUnit->_Current, texObj);
 575                break;
 576             }
 577          }
 578       }
 579
 580       if (!texUnit->_ReallyEnabled) {
 581          if (fprog) {
 582             /* If we get here it means the shader is expecting a texture
 583              * object, but there isn't one (or it's incomplete).  Use the
 584              * fallback texture.
 585              */
 586             struct gl_texture_object *texObj = _mesa_get_fallback_texture(ctx);
 587             texUnit->_ReallyEnabled = 1 << TEXTURE_2D_INDEX;
 588             _mesa_reference_texobj(&texUnit->_Current, texObj);
 589          }
 590          else {
 591             /* fixed-function: texture unit is really disabled */
 592             continue;
 593          }
 594       }
 595
 596       /* if we get here, we know this texture unit is enabled */
 597
 598       ctx->Texture._EnabledUnits |= (1 << unit);
 599
 600       if (enabledFragTargets)
 601          enabledFragUnits |= (1 << unit);
 602
 603       update_tex_combine(ctx, texUnit);
 604    }
 605
 606
 607    /* Determine which texture coordinate sets are actually needed */
 608    if (fprog) {
 609       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 610       ctx->Texture._EnabledCoordUnits
 611          = (fprog->InputsRead >> FRAG_ATTRIB_TEX0) & coordMask;
 612    }
 613    else {
 614       ctx->Texture._EnabledCoordUnits = enabledFragUnits;
 615    }
 616
 617    /* Setup texgen for those texture coordinate sets that are in use */
 618    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 619       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 620
 621       texUnit->_GenFlags = 0x0;
 622
 623       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 624          continue;
 625
 626       if (texUnit->TexGenEnabled) {
 627          if (texUnit->TexGenEnabled & S_BIT) {
 628             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 629          }
 630          if (texUnit->TexGenEnabled & T_BIT) {
 631             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 632          }
 633          if (texUnit->TexGenEnabled & R_BIT) {
 634             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 635          }
 636          if (texUnit->TexGenEnabled & Q_BIT) {
 637             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 638          }
 639
 640          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 641          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 642       }
 643
 644       ASSERT(unit < Elements(ctx->TextureMatrixStack));
 645       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 646          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 647    }
 648 }
 649
 650
 651 /**
 652  * Update texture-related derived state.
 653  */
 654 void
 655 _mesa_update_texture( struct gl_context *ctx, GLuint new_state )
 656 {
 657    if (new_state & _NEW_TEXTURE_MATRIX)
 658       update_texture_matrices( ctx );
 659
 660    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 661       update_texture_state( ctx );
 662 }
 663
 664
 665 /**********************************************************************/
 666 /*****                      Initialization                        *****/
 667 /**********************************************************************/
 668
 669 /**
 670  * Allocate the proxy textures for the given context.
 671  *
 672  * \param ctx the context to allocate proxies for.
 673  *
 674  * \return GL_TRUE on success, or GL_FALSE on failure
 675  *
 676  * If run out of memory part way through the allocations, clean up and return
 677  * GL_FALSE.
 678  */
 679 static GLboolean
 680 alloc_proxy_textures( struct gl_context *ctx )
 681 {
 682    /* NOTE: these values must be in the same order as the TEXTURE_x_INDEX
 683     * values!
 684     */
 685    static const GLenum targets[] = {
 686       GL_TEXTURE_BUFFER,
 687       GL_TEXTURE_2D_ARRAY_EXT,
 688       GL_TEXTURE_1D_ARRAY_EXT,
 689       GL_TEXTURE_CUBE_MAP_ARB,
 690       GL_TEXTURE_3D,
 691       GL_TEXTURE_2D,
 692       GL_TEXTURE_1D,
 693    };
 694    GLint tgt;
 695
 696    STATIC_ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 697    assert(targets[TEXTURE_2D_INDEX] == GL_TEXTURE_2D);
 698    assert(targets[TEXTURE_CUBE_INDEX] == GL_TEXTURE_CUBE_MAP);
 699
 700    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 701       if (!(ctx->Texture.ProxyTex[tgt]
 702             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 703          /* out of memory, free what we did allocate */
 704          while (--tgt >= 0) {
 705             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 706          }
 707          return GL_FALSE;
 708       }
 709    }
 710
 711    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 712    return GL_TRUE;
 713 }
 714
 715
 716 /**
 717  * Initialize a texture unit.
 718  *
 719  * \param ctx GL context.
 720  * \param unit texture unit number to be initialized.
 721  */
 722 static void
 723 init_texture_unit( struct gl_context *ctx, GLuint unit )
 724 {
 725    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 726    GLuint tex;
 727
 728    texUnit->EnvMode = GL_MODULATE;
 729    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 730
 731    texUnit->Combine = default_combine_state;
 732    texUnit->_EnvMode = default_combine_state;
 733    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 734    texUnit->BumpTarget = GL_TEXTURE0;
 735
 736    texUnit->TexGenEnabled = 0x0;
 737    texUnit->GenS.Mode = GL_EYE_LINEAR;
 738    texUnit->GenT.Mode = GL_EYE_LINEAR;
 739    texUnit->GenR.Mode = GL_EYE_LINEAR;
 740    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 741    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 742    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 743    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 744    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 745
 746    /* Yes, these plane coefficients are correct! */
 747    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 748    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 749    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 750    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 751    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 752    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 753    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 754    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 755
 756    /* no mention of this in spec, but maybe id matrix expected? */
 757    ASSIGN_4V( texUnit->RotMatrix, 1.0, 0.0, 0.0, 1.0 );
 758
 759    /* initialize current texture object ptrs to the shared default objects */
 760    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 761       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 762                              ctx->Shared->DefaultTex[tex]);
 763    }
 764 }
 765
 766
 767 /**
 768  * Initialize texture state for the given context.
 769  */
 770 GLboolean
 771 _mesa_init_texture(struct gl_context *ctx)
 772 {
 773    GLuint u;
 774
 775    /* Texture group */
 776    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 777    ctx->Texture._EnabledUnits = 0x0;
 778
 779    for (u = 0; u < Elements(ctx->Texture.Unit); u++)
 780       init_texture_unit(ctx, u);
 781
 782    /* After we're done initializing the context's texture state the default
 783     * texture objects' refcounts should be at least
 784     * MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1.
 785     */
 786    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 787           >= MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1);
 788
 789    /* Allocate proxy textures */
 790    if (!alloc_proxy_textures( ctx ))
 791       return GL_FALSE;
 792
 793    /* GL_ARB_texture_buffer_object */
 794    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject,
 795                                  ctx->Shared->NullBufferObj);
 796
 797    return GL_TRUE;
 798 }
 799
 800
 801 /**
 802  * Free dynamically-allocted texture data attached to the given context.
 803  */
 804 void
 805 _mesa_free_texture_data(struct gl_context *ctx)
 806 {
 807    GLuint u, tgt;
 808
 809    /* unreference current textures */
 810    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 811       /* The _Current texture could account for another reference */
 812       _mesa_reference_texobj(&ctx->Texture.Unit[u]._Current, NULL);
 813
 814       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 815          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 816       }
 817    }
 818
 819    /* Free proxy texture objects */
 820    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 821       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 822
 823    /* GL_ARB_texture_buffer_object */
 824    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject, NULL);
 825
 826 #if FEATURE_sampler_objects
 827    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 828       _mesa_reference_sampler_object(ctx, &ctx->Texture.Unit[u].Sampler, NULL);
 829    }
 830 #endif
 831 }
 832
 833
 834 /**
 835  * Update the default texture objects in the given context to reference those
 836  * specified in the shared state and release those referencing the old
 837  * shared state.
 838  */
 839 void
 840 _mesa_update_default_objects_texture(struct gl_context *ctx)
 841 {
 842    GLuint u, tex;
 843
 844    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 845       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 846       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 847          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 848                                 ctx->Shared->DefaultTex[tex]);
 849       }
 850    }
 851 }