src/mesa/main/texstate.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * 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 "bufferobj.h"
  33 #include "colormac.h"
  34 #include "colortab.h"
  35 #include "context.h"
  36 #include "enums.h"
  37 #include "macros.h"
  38 #include "shaderimage.h"
  39 #include "texobj.h"
  40 #include "teximage.h"
  41 #include "texstate.h"
  42 #include "mtypes.h"
  43 #include "bitset.h"
  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]._Current &&
 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 static void
 519 update_program_texture_state(struct gl_context *ctx, struct gl_program **prog,
 520                              BITSET_WORD *enabled_texture_units)
 521 {
 522    GLuint unit;
 523    int i;
 524
 525    for (unit = 0; unit < ctx->Const.MaxCombinedTextureImageUnits; unit++) {
 526       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 527       GLbitfield enabledTargets = 0x0;
 528       GLuint texIndex;
 529
 530       for (i = 0; i < MESA_SHADER_STAGES; i++) {
 531          if (prog[i])
 532             enabledTargets |= prog[i]->TexturesUsed[unit];
 533       }
 534
 535       if (enabledTargets == 0x0) {
 536          /* neither vertex nor fragment processing uses this unit */
 537          continue;
 538       }
 539
 540       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 541          if (enabledTargets & (1 << texIndex)) {
 542             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 543             struct gl_sampler_object *sampler = texUnit->Sampler ?
 544                texUnit->Sampler : &texObj->Sampler;
 545
 546             if (!_mesa_is_texture_complete(texObj, sampler)) {
 547                _mesa_test_texobj_completeness(ctx, texObj);
 548             }
 549             if (_mesa_is_texture_complete(texObj, sampler)) {
 550                _mesa_reference_texobj(&texUnit->_Current, texObj);
 551                break;
 552             }
 553          }
 554       }
 555
 556       if (texIndex == NUM_TEXTURE_TARGETS) {
 557          /* If we get here it means the shader is expecting a texture
 558           * object, but there isn't one (or it's incomplete).  Use the
 559           * fallback texture.
 560           */
 561          struct gl_texture_object *texObj;
 562          gl_texture_index texTarget;
 563
 564          texTarget = (gl_texture_index) (ffs(enabledTargets) - 1);
 565          texObj = _mesa_get_fallback_texture(ctx, texTarget);
 566
 567          assert(texObj);
 568          if (!texObj) {
 569             /* invalid fallback texture: don't enable the texture unit */
 570             continue;
 571          }
 572
 573          _mesa_reference_texobj(&texUnit->_Current, texObj);
 574       }
 575
 576       /* if we get here, we know this texture unit is enabled */
 577       BITSET_SET(enabled_texture_units, unit);
 578       ctx->Texture._MaxEnabledTexImageUnit =
 579          MAX2(ctx->Texture._MaxEnabledTexImageUnit, (int)unit);
 580    }
 581
 582    if (prog[MESA_SHADER_FRAGMENT]) {
 583       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 584       ctx->Texture._EnabledCoordUnits |=
 585          (prog[MESA_SHADER_FRAGMENT]->InputsRead >> VARYING_SLOT_TEX0) &
 586          coordMask;
 587    }
 588 }
 589
 590 static void
 591 update_ff_texture_state(struct gl_context *ctx,
 592                         BITSET_WORD *enabled_texture_units)
 593 {
 594    int unit;
 595
 596    for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) {
 597       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 598       GLuint texIndex;
 599
 600       if (texUnit->Enabled == 0x0)
 601          continue;
 602
 603       /* If a shader already dictated what texture target was used for this
 604        * unit, just go along with it.
 605        */
 606       if (BITSET_TEST(enabled_texture_units, unit))
 607          continue;
 608
 609       /* From the GL 4.4 compat specification, section 16.2 ("Texture Application"):
 610        *
 611        *     "Texturing is enabled or disabled using the generic Enable and
 612        *      Disable commands, respectively, with the symbolic constants
 613        *      TEXTURE_1D, TEXTURE_2D, TEXTURE_RECTANGLE, TEXTURE_3D, or
 614        *      TEXTURE_CUBE_MAP to enable the one-, two-, rectangular,
 615        *      three-dimensional, or cube map texture, respectively. If more
 616        *      than one of these textures is enabled, the first one enabled
 617        *      from the following list is used:
 618        *
 619        *      • cube map texture
 620        *      • three-dimensional texture
 621        *      • rectangular texture
 622        *      • two-dimensional texture
 623        *      • one-dimensional texture"
 624        *
 625        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 626        * Also:
 627        *
 628        *     "If a texture unit is disabled or has an invalid or incomplete
 629        *      texture (as defined in section 8.17) bound to it, then blending
 630        *      is disabled for that texture unit. If the texture environment
 631        *      for a given enabled texture unit references a disabled texture
 632        *      unit, or an invalid or incomplete texture that is bound to
 633        *      another unit, then the results of texture blending are
 634        *      undefined."
 635        */
 636       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 637          if (texUnit->Enabled & (1 << texIndex)) {
 638             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 639             struct gl_sampler_object *sampler = texUnit->Sampler ?
 640                texUnit->Sampler : &texObj->Sampler;
 641
 642             if (!_mesa_is_texture_complete(texObj, sampler)) {
 643                _mesa_test_texobj_completeness(ctx, texObj);
 644             }
 645             if (_mesa_is_texture_complete(texObj, sampler)) {
 646                _mesa_reference_texobj(&texUnit->_Current, texObj);
 647                break;
 648             }
 649          }
 650       }
 651
 652       if (texIndex == NUM_TEXTURE_TARGETS)
 653          continue;
 654
 655       /* if we get here, we know this texture unit is enabled */
 656       BITSET_SET(enabled_texture_units, unit);
 657       ctx->Texture._MaxEnabledTexImageUnit =
 658          MAX2(ctx->Texture._MaxEnabledTexImageUnit, (int)unit);
 659
 660       ctx->Texture._EnabledCoordUnits |= 1 << unit;
 661
 662       update_tex_combine(ctx, texUnit);
 663    }
 664 }
 665
 666 /**
 667  * \note This routine refers to derived texture matrix values to
 668  * compute the ENABLE_TEXMAT flags, but is only called on
 669  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 670  * flags are updated by _mesa_update_texture_matrices, above.
 671  *
 672  * \param ctx GL context.
 673  */
 674 static void
 675 update_texture_state( struct gl_context *ctx )
 676 {
 677    struct gl_program *prog[MESA_SHADER_STAGES];
 678    int i;
 679    int old_max_unit = ctx->Texture._MaxEnabledTexImageUnit;
 680    BITSET_DECLARE(enabled_texture_units, MAX_COMBINED_TEXTURE_IMAGE_UNITS);
 681
 682    for (i = 0; i < MESA_SHADER_STAGES; i++) {
 683       if (ctx->_Shader->CurrentProgram[i] &&
 684           ctx->_Shader->CurrentProgram[i]->LinkStatus) {
 685          prog[i] = ctx->_Shader->CurrentProgram[i]->_LinkedShaders[i]->Program;
 686       } else {
 687          if (i == MESA_SHADER_FRAGMENT && ctx->FragmentProgram._Enabled)
 688             prog[i] = &ctx->FragmentProgram.Current->Base;
 689          else
 690             prog[i] = NULL;
 691       }
 692    }
 693
 694    /* TODO: only set this if there are actual changes */
 695    ctx->NewState |= _NEW_TEXTURE;
 696
 697    ctx->Texture._GenFlags = 0x0;
 698    ctx->Texture._TexMatEnabled = 0x0;
 699    ctx->Texture._TexGenEnabled = 0x0;
 700    ctx->Texture._MaxEnabledTexImageUnit = -1;
 701    ctx->Texture._EnabledCoordUnits = 0x0;
 702
 703    memset(&enabled_texture_units, 0, sizeof(enabled_texture_units));
 704
 705    /* First, walk over our programs pulling in all the textures for them.
 706     * Programs dictate specific texture targets to be enabled, and for a draw
 707     * call to be valid they can't conflict about which texture targets are
 708     * used.
 709     */
 710    update_program_texture_state(ctx, prog, enabled_texture_units);
 711
 712    /* Also pull in any textures necessary for fixed function fragment shading.
 713     */
 714    if (!prog[MESA_SHADER_FRAGMENT])
 715       update_ff_texture_state(ctx, enabled_texture_units);
 716
 717    /* Now, clear out the _Current of any disabled texture units. */
 718    for (i = 0; i <= ctx->Texture._MaxEnabledTexImageUnit; i++) {
 719       if (!BITSET_TEST(enabled_texture_units, i))
 720          _mesa_reference_texobj(&ctx->Texture.Unit[i]._Current, NULL);
 721    }
 722    for (i = ctx->Texture._MaxEnabledTexImageUnit + 1; i <= old_max_unit; i++) {
 723       _mesa_reference_texobj(&ctx->Texture.Unit[i]._Current, NULL);
 724    }
 725
 726    if (!prog[MESA_SHADER_FRAGMENT] || !prog[MESA_SHADER_VERTEX])
 727       update_texgen(ctx);
 728
 729    _mesa_validate_image_units(ctx);
 730 }
 731
 732
 733 /**
 734  * Update texture-related derived state.
 735  */
 736 void
 737 _mesa_update_texture( struct gl_context *ctx, GLuint new_state )
 738 {
 739    if (new_state & _NEW_TEXTURE_MATRIX)
 740       update_texture_matrices( ctx );
 741
 742    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 743       update_texture_state( ctx );
 744 }
 745
 746
 747 /**********************************************************************/
 748 /*****                      Initialization                        *****/
 749 /**********************************************************************/
 750
 751 /**
 752  * Allocate the proxy textures for the given context.
 753  *
 754  * \param ctx the context to allocate proxies for.
 755  *
 756  * \return GL_TRUE on success, or GL_FALSE on failure
 757  *
 758  * If run out of memory part way through the allocations, clean up and return
 759  * GL_FALSE.
 760  */
 761 static GLboolean
 762 alloc_proxy_textures( struct gl_context *ctx )
 763 {
 764    /* NOTE: these values must be in the same order as the TEXTURE_x_INDEX
 765     * values!
 766     */
 767    static const GLenum targets[] = {
 768       GL_TEXTURE_2D_MULTISAMPLE,
 769       GL_TEXTURE_2D_MULTISAMPLE_ARRAY,
 770       GL_TEXTURE_CUBE_MAP_ARRAY,
 771       GL_TEXTURE_BUFFER,
 772       GL_TEXTURE_2D_ARRAY_EXT,
 773       GL_TEXTURE_1D_ARRAY_EXT,
 774       GL_TEXTURE_EXTERNAL_OES,
 775       GL_TEXTURE_CUBE_MAP_ARB,
 776       GL_TEXTURE_3D,
 777       GL_TEXTURE_RECTANGLE_NV,
 778       GL_TEXTURE_2D,
 779       GL_TEXTURE_1D,
 780    };
 781    GLint tgt;
 782
 783    STATIC_ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 784    assert(targets[TEXTURE_2D_INDEX] == GL_TEXTURE_2D);
 785    assert(targets[TEXTURE_CUBE_INDEX] == GL_TEXTURE_CUBE_MAP);
 786
 787    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 788       if (!(ctx->Texture.ProxyTex[tgt]
 789             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 790          /* out of memory, free what we did allocate */
 791          while (--tgt >= 0) {
 792             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 793          }
 794          return GL_FALSE;
 795       }
 796    }
 797
 798    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 799    return GL_TRUE;
 800 }
 801
 802
 803 /**
 804  * Initialize a texture unit.
 805  *
 806  * \param ctx GL context.
 807  * \param unit texture unit number to be initialized.
 808  */
 809 static void
 810 init_texture_unit( struct gl_context *ctx, GLuint unit )
 811 {
 812    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 813    GLuint tex;
 814
 815    texUnit->EnvMode = GL_MODULATE;
 816    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 817
 818    texUnit->Combine = default_combine_state;
 819    texUnit->_EnvMode = default_combine_state;
 820    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 821    texUnit->BumpTarget = GL_TEXTURE0;
 822
 823    texUnit->TexGenEnabled = 0x0;
 824    texUnit->GenS.Mode = GL_EYE_LINEAR;
 825    texUnit->GenT.Mode = GL_EYE_LINEAR;
 826    texUnit->GenR.Mode = GL_EYE_LINEAR;
 827    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 828    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 829    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 830    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 831    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 832
 833    /* Yes, these plane coefficients are correct! */
 834    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 835    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 836    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 837    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 838    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 839    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 840    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 841    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 842
 843    /* no mention of this in spec, but maybe id matrix expected? */
 844    ASSIGN_4V( texUnit->RotMatrix, 1.0, 0.0, 0.0, 1.0 );
 845
 846    /* initialize current texture object ptrs to the shared default objects */
 847    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 848       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 849                              ctx->Shared->DefaultTex[tex]);
 850    }
 851 }
 852
 853
 854 /**
 855  * Initialize texture state for the given context.
 856  */
 857 GLboolean
 858 _mesa_init_texture(struct gl_context *ctx)
 859 {
 860    GLuint u;
 861
 862    /* Texture group */
 863    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 864
 865    /* Appendix F.2 of the OpenGL ES 3.0 spec says:
 866     *
 867     *     "OpenGL ES 3.0 requires that all cube map filtering be
 868     *     seamless. OpenGL ES 2.0 specified that a single cube map face be
 869     *     selected and used for filtering."
 870     */
 871    ctx->Texture.CubeMapSeamless = _mesa_is_gles3(ctx);
 872
 873    for (u = 0; u < Elements(ctx->Texture.Unit); u++)
 874       init_texture_unit(ctx, u);
 875
 876    /* After we're done initializing the context's texture state the default
 877     * texture objects' refcounts should be at least
 878     * MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1.
 879     */
 880    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 881           >= MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1);
 882
 883    /* Allocate proxy textures */
 884    if (!alloc_proxy_textures( ctx ))
 885       return GL_FALSE;
 886
 887    /* GL_ARB_texture_buffer_object */
 888    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject,
 889                                  ctx->Shared->NullBufferObj);
 890
 891    return GL_TRUE;
 892 }
 893
 894
 895 /**
 896  * Free dynamically-allocted texture data attached to the given context.
 897  */
 898 void
 899 _mesa_free_texture_data(struct gl_context *ctx)
 900 {
 901    GLuint u, tgt;
 902
 903    /* unreference current textures */
 904    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 905       /* The _Current texture could account for another reference */
 906       _mesa_reference_texobj(&ctx->Texture.Unit[u]._Current, NULL);
 907
 908       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 909          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 910       }
 911    }
 912
 913    /* Free proxy texture objects */
 914    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 915       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 916
 917    /* GL_ARB_texture_buffer_object */
 918    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject, NULL);
 919
 920    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 921       _mesa_reference_sampler_object(ctx, &ctx->Texture.Unit[u].Sampler, NULL);
 922    }
 923 }
 924
 925
 926 /**
 927  * Update the default texture objects in the given context to reference those
 928  * specified in the shared state and release those referencing the old
 929  * shared state.
 930  */
 931 void
 932 _mesa_update_default_objects_texture(struct gl_context *ctx)
 933 {
 934    GLuint u, tex;
 935
 936    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 937       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 938       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 939          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 940                                 ctx->Shared->DefaultTex[tex]);
 941       }
 942    }
 943 }