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_ActiveTexture(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    if (MESA_VERBOSE & (VERBOSE_API|VERBOSE_TEXTURE))
 302       _mesa_debug(ctx, "glActiveTexture %s\n",
 303                   _mesa_lookup_enum_by_nr(texture));
 304
 305    if (texUnit >= k) {
 306       _mesa_error(ctx, GL_INVALID_ENUM, "glActiveTexture(texture=%s)",
 307                   _mesa_lookup_enum_by_nr(texture));
 308       return;
 309    }
 310
 311    if (ctx->Texture.CurrentUnit == texUnit)
 312       return;
 313
 314    FLUSH_VERTICES(ctx, _NEW_TEXTURE);
 315
 316    ctx->Texture.CurrentUnit = texUnit;
 317    if (ctx->Transform.MatrixMode == GL_TEXTURE) {
 318       /* update current stack pointer */
 319       ctx->CurrentStack = &ctx->TextureMatrixStack[texUnit];
 320    }
 321 }
 322
 323
 324 /* GL_ARB_multitexture */
 325 void GLAPIENTRY
 326 _mesa_ClientActiveTexture(GLenum texture)
 327 {
 328    GET_CURRENT_CONTEXT(ctx);
 329    GLuint texUnit = texture - GL_TEXTURE0;
 330
 331    if (MESA_VERBOSE & (VERBOSE_API | VERBOSE_TEXTURE))
 332       _mesa_debug(ctx, "glClientActiveTexture %s\n",
 333                   _mesa_lookup_enum_by_nr(texture));
 334
 335    if (texUnit >= ctx->Const.MaxTextureCoordUnits) {
 336       _mesa_error(ctx, GL_INVALID_ENUM, "glClientActiveTexture(texture)");
 337       return;
 338    }
 339
 340    if (ctx->Array.ActiveTexture == texUnit)
 341       return;
 342
 343    FLUSH_VERTICES(ctx, _NEW_ARRAY);
 344    ctx->Array.ActiveTexture = texUnit;
 345 }
 346
 347
 348
 349 /**********************************************************************/
 350 /*****                    State management                        *****/
 351 /**********************************************************************/
 352
 353
 354 /**
 355  * \note This routine refers to derived texture attribute values to
 356  * compute the ENABLE_TEXMAT flags, but is only called on
 357  * _NEW_TEXTURE_MATRIX.  On changes to _NEW_TEXTURE, the ENABLE_TEXMAT
 358  * flags are updated by _mesa_update_textures(), below.
 359  *
 360  * \param ctx GL context.
 361  */
 362 static void
 363 update_texture_matrices( struct gl_context *ctx )
 364 {
 365    GLuint u;
 366
 367    ctx->Texture._TexMatEnabled = 0x0;
 368
 369    for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
 370       ASSERT(u < Elements(ctx->TextureMatrixStack));
 371       if (_math_matrix_is_dirty(ctx->TextureMatrixStack[u].Top)) {
 372          _math_matrix_analyse( ctx->TextureMatrixStack[u].Top );
 373
 374          if (ctx->Texture.Unit[u]._ReallyEnabled &&
 375              ctx->TextureMatrixStack[u].Top->type != MATRIX_IDENTITY)
 376             ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(u);
 377       }
 378    }
 379 }
 380
 381
 382 /**
 383  * Examine texture unit's combine/env state to update derived state.
 384  */
 385 static void
 386 update_tex_combine(struct gl_context *ctx, struct gl_texture_unit *texUnit)
 387 {
 388    struct gl_tex_env_combine_state *combine;
 389
 390    /* No combiners will apply to this. */
 391    if (texUnit->_Current->Target == GL_TEXTURE_BUFFER)
 392       return;
 393
 394    /* Set the texUnit->_CurrentCombine field to point to the user's combiner
 395     * state, or the combiner state which is derived from traditional texenv
 396     * mode.
 397     */
 398    if (texUnit->EnvMode == GL_COMBINE ||
 399        texUnit->EnvMode == GL_COMBINE4_NV) {
 400       texUnit->_CurrentCombine = & texUnit->Combine;
 401    }
 402    else {
 403       const struct gl_texture_object *texObj = texUnit->_Current;
 404       GLenum format = texObj->Image[0][texObj->BaseLevel]->_BaseFormat;
 405
 406       if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL_EXT) {
 407          format = texObj->DepthMode;
 408       }
 409       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 410       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 411    }
 412
 413    combine = texUnit->_CurrentCombine;
 414
 415    /* Determine number of source RGB terms in the combiner function */
 416    switch (combine->ModeRGB) {
 417    case GL_REPLACE:
 418       combine->_NumArgsRGB = 1;
 419       break;
 420    case GL_ADD:
 421    case GL_ADD_SIGNED:
 422       if (texUnit->EnvMode == GL_COMBINE4_NV)
 423          combine->_NumArgsRGB = 4;
 424       else
 425          combine->_NumArgsRGB = 2;
 426       break;
 427    case GL_MODULATE:
 428    case GL_SUBTRACT:
 429    case GL_DOT3_RGB:
 430    case GL_DOT3_RGBA:
 431    case GL_DOT3_RGB_EXT:
 432    case GL_DOT3_RGBA_EXT:
 433       combine->_NumArgsRGB = 2;
 434       break;
 435    case GL_INTERPOLATE:
 436    case GL_MODULATE_ADD_ATI:
 437    case GL_MODULATE_SIGNED_ADD_ATI:
 438    case GL_MODULATE_SUBTRACT_ATI:
 439       combine->_NumArgsRGB = 3;
 440       break;
 441    case GL_BUMP_ENVMAP_ATI:
 442       /* no real arguments for this case */
 443       combine->_NumArgsRGB = 0;
 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 static void
 481 update_texgen(struct gl_context *ctx)
 482 {
 483    GLuint unit;
 484
 485    /* Setup texgen for those texture coordinate sets that are in use */
 486    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 487       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 488
 489       texUnit->_GenFlags = 0x0;
 490
 491       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 492          continue;
 493
 494       if (texUnit->TexGenEnabled) {
 495          if (texUnit->TexGenEnabled & S_BIT) {
 496             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 497          }
 498          if (texUnit->TexGenEnabled & T_BIT) {
 499             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 500          }
 501          if (texUnit->TexGenEnabled & R_BIT) {
 502             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 503          }
 504          if (texUnit->TexGenEnabled & Q_BIT) {
 505             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 506          }
 507
 508          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 509          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 510       }
 511
 512       ASSERT(unit < Elements(ctx->TextureMatrixStack));
 513       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 514          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 515    }
 516 }
 517
 518 /**
 519  * \note This routine refers to derived texture matrix values to
 520  * compute the ENABLE_TEXMAT flags, but is only called on
 521  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 522  * flags are updated by _mesa_update_texture_matrices, above.
 523  *
 524  * \param ctx GL context.
 525  */
 526 static void
 527 update_texture_state( struct gl_context *ctx )
 528 {
 529    GLuint unit;
 530    struct gl_program *fprog = NULL;
 531    struct gl_program *vprog = NULL;
 532    GLbitfield enabledFragUnits = 0x0;
 533
 534    if (ctx->Shader.CurrentVertexProgram &&
 535        ctx->Shader.CurrentVertexProgram->LinkStatus) {
 536       vprog = ctx->Shader.CurrentVertexProgram->_LinkedShaders[MESA_SHADER_VERTEX]->Program;
 537    }
 538
 539    if (ctx->Shader.CurrentFragmentProgram &&
 540        ctx->Shader.CurrentFragmentProgram->LinkStatus) {
 541       fprog = ctx->Shader.CurrentFragmentProgram->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program;
 542    }
 543    else if (ctx->FragmentProgram._Enabled) {
 544       fprog = &ctx->FragmentProgram.Current->Base;
 545    }
 546
 547    /* FINISHME: Geometry shader texture accesses should also be considered
 548     * FINISHME: here.
 549     */
 550
 551    /* TODO: only set this if there are actual changes */
 552    ctx->NewState |= _NEW_TEXTURE;
 553
 554    ctx->Texture._EnabledUnits = 0x0;
 555    ctx->Texture._GenFlags = 0x0;
 556    ctx->Texture._TexMatEnabled = 0x0;
 557    ctx->Texture._TexGenEnabled = 0x0;
 558
 559    /*
 560     * Update texture unit state.
 561     */
 562    for (unit = 0; unit < ctx->Const.MaxCombinedTextureImageUnits; unit++) {
 563       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 564       GLbitfield enabledVertTargets = 0x0;
 565       GLbitfield enabledFragTargets = 0x0;
 566       GLbitfield enabledTargets = 0x0;
 567       GLuint texIndex;
 568
 569       /* Get the bitmask of texture target enables.
 570        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 571        * which texture targets are enabled (fixed function) or referenced
 572        * by a fragment program/program.  When multiple flags are set, we'll
 573        * settle on the one with highest priority (see below).
 574        */
 575       if (vprog) {
 576          enabledVertTargets |= vprog->TexturesUsed[unit];
 577       }
 578
 579       if (fprog) {
 580          enabledFragTargets |= fprog->TexturesUsed[unit];
 581       }
 582       else {
 583          /* fixed-function fragment program */
 584          enabledFragTargets |= texUnit->Enabled;
 585       }
 586
 587       enabledTargets = enabledVertTargets | enabledFragTargets;
 588
 589       texUnit->_ReallyEnabled = 0x0;
 590
 591       if (enabledTargets == 0x0) {
 592          /* neither vertex nor fragment processing uses this unit */
 593          continue;
 594       }
 595
 596       /* Look for the highest priority texture target that's enabled (or used
 597        * by the vert/frag shaders) and "complete".  That's the one we'll use
 598        * for texturing.  If we're using vert/frag program we're guaranteed
 599        * that bitcount(enabledBits) <= 1.
 600        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 601        */
 602       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 603          if (enabledTargets & (1 << texIndex)) {
 604             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 605             struct gl_sampler_object *sampler = texUnit->Sampler ?
 606                texUnit->Sampler : &texObj->Sampler;
 607
 608             if (!_mesa_is_texture_complete(texObj, sampler)) {
 609                _mesa_test_texobj_completeness(ctx, texObj);
 610             }
 611             if (_mesa_is_texture_complete(texObj, sampler)) {
 612                texUnit->_ReallyEnabled = 1 << texIndex;
 613                _mesa_reference_texobj(&texUnit->_Current, texObj);
 614                break;
 615             }
 616          }
 617       }
 618
 619       if (!texUnit->_ReallyEnabled) {
 620          if (fprog) {
 621             /* If we get here it means the shader is expecting a texture
 622              * object, but there isn't one (or it's incomplete).  Use the
 623              * fallback texture.
 624              */
 625             struct gl_texture_object *texObj;
 626             gl_texture_index texTarget;
 627
 628             assert(_mesa_bitcount(enabledTargets) == 1);
 629
 630             texTarget = (gl_texture_index) (ffs(enabledTargets) - 1);
 631             texObj = _mesa_get_fallback_texture(ctx, texTarget);
 632
 633             assert(texObj);
 634             if (!texObj) {
 635                /* invalid fallback texture: don't enable the texture unit */
 636                continue;
 637             }
 638
 639             _mesa_reference_texobj(&texUnit->_Current, texObj);
 640             texUnit->_ReallyEnabled = 1 << texTarget;
 641          }
 642          else {
 643             /* fixed-function: texture unit is really disabled */
 644             continue;
 645          }
 646       }
 647
 648       /* if we get here, we know this texture unit is enabled */
 649
 650       ctx->Texture._EnabledUnits |= (1 << unit);
 651
 652       if (enabledFragTargets)
 653          enabledFragUnits |= (1 << unit);
 654
 655       if (!fprog)
 656          update_tex_combine(ctx, texUnit);
 657    }
 658
 659
 660    /* Determine which texture coordinate sets are actually needed */
 661    if (fprog) {
 662       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 663       ctx->Texture._EnabledCoordUnits
 664          = (fprog->InputsRead >> VARYING_SLOT_TEX0) & coordMask;
 665    }
 666    else {
 667       ctx->Texture._EnabledCoordUnits = enabledFragUnits;
 668    }
 669
 670    if (!fprog || !vprog)
 671       update_texgen(ctx);
 672 }
 673
 674
 675 /**
 676  * Update texture-related derived state.
 677  */
 678 void
 679 _mesa_update_texture( struct gl_context *ctx, GLuint new_state )
 680 {
 681    if (new_state & _NEW_TEXTURE_MATRIX)
 682       update_texture_matrices( ctx );
 683
 684    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 685       update_texture_state( ctx );
 686 }
 687
 688
 689 /**********************************************************************/
 690 /*****                      Initialization                        *****/
 691 /**********************************************************************/
 692
 693 /**
 694  * Allocate the proxy textures for the given context.
 695  *
 696  * \param ctx the context to allocate proxies for.
 697  *
 698  * \return GL_TRUE on success, or GL_FALSE on failure
 699  *
 700  * If run out of memory part way through the allocations, clean up and return
 701  * GL_FALSE.
 702  */
 703 static GLboolean
 704 alloc_proxy_textures( struct gl_context *ctx )
 705 {
 706    /* NOTE: these values must be in the same order as the TEXTURE_x_INDEX
 707     * values!
 708     */
 709    static const GLenum targets[] = {
 710       GL_TEXTURE_2D_MULTISAMPLE,
 711       GL_TEXTURE_2D_MULTISAMPLE_ARRAY,
 712       GL_TEXTURE_CUBE_MAP_ARRAY,
 713       GL_TEXTURE_BUFFER,
 714       GL_TEXTURE_2D_ARRAY_EXT,
 715       GL_TEXTURE_1D_ARRAY_EXT,
 716       GL_TEXTURE_EXTERNAL_OES,
 717       GL_TEXTURE_CUBE_MAP_ARB,
 718       GL_TEXTURE_3D,
 719       GL_TEXTURE_RECTANGLE_NV,
 720       GL_TEXTURE_2D,
 721       GL_TEXTURE_1D,
 722    };
 723    GLint tgt;
 724
 725    STATIC_ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 726    assert(targets[TEXTURE_2D_INDEX] == GL_TEXTURE_2D);
 727    assert(targets[TEXTURE_CUBE_INDEX] == GL_TEXTURE_CUBE_MAP);
 728
 729    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 730       if (!(ctx->Texture.ProxyTex[tgt]
 731             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 732          /* out of memory, free what we did allocate */
 733          while (--tgt >= 0) {
 734             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 735          }
 736          return GL_FALSE;
 737       }
 738    }
 739
 740    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 741    return GL_TRUE;
 742 }
 743
 744
 745 /**
 746  * Initialize a texture unit.
 747  *
 748  * \param ctx GL context.
 749  * \param unit texture unit number to be initialized.
 750  */
 751 static void
 752 init_texture_unit( struct gl_context *ctx, GLuint unit )
 753 {
 754    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 755    GLuint tex;
 756
 757    texUnit->EnvMode = GL_MODULATE;
 758    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 759
 760    texUnit->Combine = default_combine_state;
 761    texUnit->_EnvMode = default_combine_state;
 762    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 763    texUnit->BumpTarget = GL_TEXTURE0;
 764
 765    texUnit->TexGenEnabled = 0x0;
 766    texUnit->GenS.Mode = GL_EYE_LINEAR;
 767    texUnit->GenT.Mode = GL_EYE_LINEAR;
 768    texUnit->GenR.Mode = GL_EYE_LINEAR;
 769    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 770    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 771    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 772    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 773    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 774
 775    /* Yes, these plane coefficients are correct! */
 776    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 777    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 778    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 779    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 780    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 781    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 782    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 783    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 784
 785    /* no mention of this in spec, but maybe id matrix expected? */
 786    ASSIGN_4V( texUnit->RotMatrix, 1.0, 0.0, 0.0, 1.0 );
 787
 788    /* initialize current texture object ptrs to the shared default objects */
 789    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 790       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 791                              ctx->Shared->DefaultTex[tex]);
 792    }
 793 }
 794
 795
 796 /**
 797  * Initialize texture state for the given context.
 798  */
 799 GLboolean
 800 _mesa_init_texture(struct gl_context *ctx)
 801 {
 802    GLuint u;
 803
 804    /* Texture group */
 805    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 806    ctx->Texture._EnabledUnits = 0x0;
 807
 808    for (u = 0; u < Elements(ctx->Texture.Unit); u++)
 809       init_texture_unit(ctx, u);
 810
 811    /* After we're done initializing the context's texture state the default
 812     * texture objects' refcounts should be at least
 813     * MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1.
 814     */
 815    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 816           >= MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1);
 817
 818    /* Allocate proxy textures */
 819    if (!alloc_proxy_textures( ctx ))
 820       return GL_FALSE;
 821
 822    /* GL_ARB_texture_buffer_object */
 823    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject,
 824                                  ctx->Shared->NullBufferObj);
 825
 826    return GL_TRUE;
 827 }
 828
 829
 830 /**
 831  * Free dynamically-allocted texture data attached to the given context.
 832  */
 833 void
 834 _mesa_free_texture_data(struct gl_context *ctx)
 835 {
 836    GLuint u, tgt;
 837
 838    /* unreference current textures */
 839    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 840       /* The _Current texture could account for another reference */
 841       _mesa_reference_texobj(&ctx->Texture.Unit[u]._Current, NULL);
 842
 843       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 844          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 845       }
 846    }
 847
 848    /* Free proxy texture objects */
 849    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 850       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 851
 852    /* GL_ARB_texture_buffer_object */
 853    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject, NULL);
 854
 855    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 856       _mesa_reference_sampler_object(ctx, &ctx->Texture.Unit[u].Sampler, NULL);
 857    }
 858 }
 859
 860
 861 /**
 862  * Update the default texture objects in the given context to reference those
 863  * specified in the shared state and release those referencing the old
 864  * shared state.
 865  */
 866 void
 867 _mesa_update_default_objects_texture(struct gl_context *ctx)
 868 {
 869    GLuint u, tex;
 870
 871    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 872       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 873       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 874          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 875                                 ctx->Shared->DefaultTex[tex]);
 876       }
 877    }
 878 }