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 "texobj.h"
  39 #include "teximage.h"
  40 #include "texstate.h"
  41 #include "mtypes.h"
  42
  43
  44
  45 /**
  46  * Default texture combine environment state.  This is used to initialize
  47  * a context's texture units and as the basis for converting "classic"
  48  * texture environmnets to ARB_texture_env_combine style values.
  49  */
  50 static const struct gl_tex_env_combine_state default_combine_state = {
  51    GL_MODULATE, GL_MODULATE,
  52    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  53    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  54    { GL_SRC_COLOR, GL_SRC_COLOR, GL_SRC_ALPHA, GL_SRC_ALPHA },
  55    { GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA },
  56    0, 0,
  57    2, 2
  58 };
  59
  60
  61
  62 /**
  63  * Used by glXCopyContext to copy texture state from one context to another.
  64  */
  65 void
  66 _mesa_copy_texture_state( const struct gl_context *src, struct gl_context *dst )
  67 {
  68    GLuint u, tex;
  69
  70    ASSERT(src);
  71    ASSERT(dst);
  72
  73    dst->Texture.CurrentUnit = src->Texture.CurrentUnit;
  74    dst->Texture._GenFlags = src->Texture._GenFlags;
  75    dst->Texture._TexGenEnabled = src->Texture._TexGenEnabled;
  76    dst->Texture._TexMatEnabled = src->Texture._TexMatEnabled;
  77
  78    /* per-unit state */
  79    for (u = 0; u < src->Const.MaxCombinedTextureImageUnits; u++) {
  80       dst->Texture.Unit[u].Enabled = src->Texture.Unit[u].Enabled;
  81       dst->Texture.Unit[u].EnvMode = src->Texture.Unit[u].EnvMode;
  82       COPY_4V(dst->Texture.Unit[u].EnvColor, src->Texture.Unit[u].EnvColor);
  83       dst->Texture.Unit[u].TexGenEnabled = src->Texture.Unit[u].TexGenEnabled;
  84       dst->Texture.Unit[u].GenS = src->Texture.Unit[u].GenS;
  85       dst->Texture.Unit[u].GenT = src->Texture.Unit[u].GenT;
  86       dst->Texture.Unit[u].GenR = src->Texture.Unit[u].GenR;
  87       dst->Texture.Unit[u].GenQ = src->Texture.Unit[u].GenQ;
  88       dst->Texture.Unit[u].LodBias = src->Texture.Unit[u].LodBias;
  89
  90       /* GL_EXT_texture_env_combine */
  91       dst->Texture.Unit[u].Combine = src->Texture.Unit[u].Combine;
  92
  93       /* GL_ATI_envmap_bumpmap - need this? */
  94       dst->Texture.Unit[u].BumpTarget = src->Texture.Unit[u].BumpTarget;
  95       COPY_4V(dst->Texture.Unit[u].RotMatrix, src->Texture.Unit[u].RotMatrix);
  96
  97       /*
  98        * XXX strictly speaking, we should compare texture names/ids and
  99        * bind textures in the dest context according to id.  For now, only
 100        * copy bindings if the contexts share the same pool of textures to
 101        * avoid refcounting bugs.
 102        */
 103       if (dst->Shared == src->Shared) {
 104          /* copy texture object bindings, not contents of texture objects */
 105          _mesa_lock_context_textures(dst);
 106
 107          for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 108             _mesa_reference_texobj(&dst->Texture.Unit[u].CurrentTex[tex],
 109                                    src->Texture.Unit[u].CurrentTex[tex]);
 110          }
 111          _mesa_unlock_context_textures(dst);
 112       }
 113    }
 114 }
 115
 116
 117 /*
 118  * For debugging
 119  */
 120 void
 121 _mesa_print_texunit_state( struct gl_context *ctx, GLuint unit )
 122 {
 123    const struct gl_texture_unit *texUnit = ctx->Texture.Unit + unit;
 124    printf("Texture Unit %d\n", unit);
 125    printf("  GL_TEXTURE_ENV_MODE = %s\n", _mesa_lookup_enum_by_nr(texUnit->EnvMode));
 126    printf("  GL_COMBINE_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeRGB));
 127    printf("  GL_COMBINE_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeA));
 128    printf("  GL_SOURCE0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[0]));
 129    printf("  GL_SOURCE1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[1]));
 130    printf("  GL_SOURCE2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[2]));
 131    printf("  GL_SOURCE0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[0]));
 132    printf("  GL_SOURCE1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[1]));
 133    printf("  GL_SOURCE2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[2]));
 134    printf("  GL_OPERAND0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[0]));
 135    printf("  GL_OPERAND1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[1]));
 136    printf("  GL_OPERAND2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[2]));
 137    printf("  GL_OPERAND0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[0]));
 138    printf("  GL_OPERAND1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[1]));
 139    printf("  GL_OPERAND2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[2]));
 140    printf("  GL_RGB_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftRGB);
 141    printf("  GL_ALPHA_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftA);
 142    printf("  GL_TEXTURE_ENV_COLOR = (%f, %f, %f, %f)\n", texUnit->EnvColor[0], texUnit->EnvColor[1], texUnit->EnvColor[2], texUnit->EnvColor[3]);
 143 }
 144
 145
 146
 147 /**********************************************************************/
 148 /*                       Texture Environment                          */
 149 /**********************************************************************/
 150
 151 /**
 152  * Convert "classic" texture environment to ARB_texture_env_combine style
 153  * environments.
 154  *
 155  * \param state  texture_env_combine state vector to be filled-in.
 156  * \param mode   Classic texture environment mode (i.e., \c GL_REPLACE,
 157  *               \c GL_BLEND, \c GL_DECAL, etc.).
 158  * \param texBaseFormat  Base format of the texture associated with the
 159  *               texture unit.
 160  */
 161 static void
 162 calculate_derived_texenv( struct gl_tex_env_combine_state *state,
 163                           GLenum mode, GLenum texBaseFormat )
 164 {
 165    GLenum mode_rgb;
 166    GLenum mode_a;
 167
 168    *state = default_combine_state;
 169
 170    switch (texBaseFormat) {
 171    case GL_ALPHA:
 172       state->SourceRGB[0] = GL_PREVIOUS;
 173       break;
 174
 175    case GL_LUMINANCE_ALPHA:
 176    case GL_INTENSITY:
 177    case GL_RGBA:
 178       break;
 179
 180    case GL_LUMINANCE:
 181    case GL_RED:
 182    case GL_RG:
 183    case GL_RGB:
 184    case GL_YCBCR_MESA:
 185    case GL_DUDV_ATI:
 186       state->SourceA[0] = GL_PREVIOUS;
 187       break;
 188
 189    default:
 190       _mesa_problem(NULL,
 191                     "Invalid texBaseFormat 0x%x in calculate_derived_texenv",
 192                     texBaseFormat);
 193       return;
 194    }
 195
 196    if (mode == GL_REPLACE_EXT)
 197       mode = GL_REPLACE;
 198
 199    switch (mode) {
 200    case GL_REPLACE:
 201    case GL_MODULATE:
 202       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : mode;
 203       mode_a   = mode;
 204       break;
 205
 206    case GL_DECAL:
 207       mode_rgb = GL_INTERPOLATE;
 208       mode_a   = GL_REPLACE;
 209
 210       state->SourceA[0] = GL_PREVIOUS;
 211
 212       /* Having alpha / luminance / intensity textures replace using the
 213        * incoming fragment color matches the definition in NV_texture_shader.
 214        * The 1.5 spec simply marks these as "undefined".
 215        */
 216       switch (texBaseFormat) {
 217       case GL_ALPHA:
 218       case GL_LUMINANCE:
 219       case GL_LUMINANCE_ALPHA:
 220       case GL_INTENSITY:
 221          state->SourceRGB[0] = GL_PREVIOUS;
 222          break;
 223       case GL_RED:
 224       case GL_RG:
 225       case GL_RGB:
 226       case GL_YCBCR_MESA:
 227       case GL_DUDV_ATI:
 228          mode_rgb = GL_REPLACE;
 229          break;
 230       case GL_RGBA:
 231          state->SourceRGB[2] = GL_TEXTURE;
 232          break;
 233       }
 234       break;
 235
 236    case GL_BLEND:
 237       mode_rgb = GL_INTERPOLATE;
 238       mode_a   = GL_MODULATE;
 239
 240       switch (texBaseFormat) {
 241       case GL_ALPHA:
 242          mode_rgb = GL_REPLACE;
 243          break;
 244       case GL_INTENSITY:
 245          mode_a = GL_INTERPOLATE;
 246          state->SourceA[0] = GL_CONSTANT;
 247          state->OperandA[2] = GL_SRC_ALPHA;
 248          /* FALLTHROUGH */
 249       case GL_LUMINANCE:
 250       case GL_RED:
 251       case GL_RG:
 252       case GL_RGB:
 253       case GL_LUMINANCE_ALPHA:
 254       case GL_RGBA:
 255       case GL_YCBCR_MESA:
 256       case GL_DUDV_ATI:
 257          state->SourceRGB[2] = GL_TEXTURE;
 258          state->SourceA[2]   = GL_TEXTURE;
 259          state->SourceRGB[0] = GL_CONSTANT;
 260          state->OperandRGB[2] = GL_SRC_COLOR;
 261          break;
 262       }
 263       break;
 264
 265    case GL_ADD:
 266       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : GL_ADD;
 267       mode_a   = (texBaseFormat == GL_INTENSITY) ? GL_ADD : GL_MODULATE;
 268       break;
 269
 270    default:
 271       _mesa_problem(NULL,
 272                     "Invalid texture env mode 0x%x in calculate_derived_texenv",
 273                     mode);
 274       return;
 275    }
 276
 277    state->ModeRGB = (state->SourceRGB[0] != GL_PREVIOUS)
 278        ? mode_rgb : GL_REPLACE;
 279    state->ModeA   = (state->SourceA[0]   != GL_PREVIOUS)
 280        ? mode_a   : GL_REPLACE;
 281 }
 282
 283
 284
 285
 286 /* GL_ARB_multitexture */
 287 void GLAPIENTRY
 288 _mesa_ActiveTexture(GLenum texture)
 289 {
 290    const GLuint texUnit = texture - GL_TEXTURE0;
 291    GLuint k;
 292    GET_CURRENT_CONTEXT(ctx);
 293
 294    /* See OpenGL spec for glActiveTexture: */
 295    k = MAX2(ctx->Const.MaxCombinedTextureImageUnits,
 296             ctx->Const.MaxTextureCoordUnits);
 297
 298    ASSERT(k <= Elements(ctx->Texture.Unit));
 299
 300    if (MESA_VERBOSE & (VERBOSE_API|VERBOSE_TEXTURE))
 301       _mesa_debug(ctx, "glActiveTexture %s\n",
 302                   _mesa_lookup_enum_by_nr(texture));
 303
 304    if (texUnit >= k) {
 305       _mesa_error(ctx, GL_INVALID_ENUM, "glActiveTexture(texture=%s)",
 306                   _mesa_lookup_enum_by_nr(texture));
 307       return;
 308    }
 309
 310    if (ctx->Texture.CurrentUnit == texUnit)
 311       return;
 312
 313    FLUSH_VERTICES(ctx, _NEW_TEXTURE);
 314
 315    ctx->Texture.CurrentUnit = texUnit;
 316    if (ctx->Transform.MatrixMode == GL_TEXTURE) {
 317       /* update current stack pointer */
 318       ctx->CurrentStack = &ctx->TextureMatrixStack[texUnit];
 319    }
 320 }
 321
 322
 323 /* GL_ARB_multitexture */
 324 void GLAPIENTRY
 325 _mesa_ClientActiveTexture(GLenum texture)
 326 {
 327    GET_CURRENT_CONTEXT(ctx);
 328    GLuint texUnit = texture - GL_TEXTURE0;
 329
 330    if (MESA_VERBOSE & (VERBOSE_API | VERBOSE_TEXTURE))
 331       _mesa_debug(ctx, "glClientActiveTexture %s\n",
 332                   _mesa_lookup_enum_by_nr(texture));
 333
 334    if (texUnit >= ctx->Const.MaxTextureCoordUnits) {
 335       _mesa_error(ctx, GL_INVALID_ENUM, "glClientActiveTexture(texture)");
 336       return;
 337    }
 338
 339    if (ctx->Array.ActiveTexture == texUnit)
 340       return;
 341
 342    FLUSH_VERTICES(ctx, _NEW_ARRAY);
 343    ctx->Array.ActiveTexture = texUnit;
 344 }
 345
 346
 347
 348 /**********************************************************************/
 349 /*****                    State management                        *****/
 350 /**********************************************************************/
 351
 352
 353 /**
 354  * \note This routine refers to derived texture attribute values to
 355  * compute the ENABLE_TEXMAT flags, but is only called on
 356  * _NEW_TEXTURE_MATRIX.  On changes to _NEW_TEXTURE, the ENABLE_TEXMAT
 357  * flags are updated by _mesa_update_textures(), below.
 358  *
 359  * \param ctx GL context.
 360  */
 361 static void
 362 update_texture_matrices( struct gl_context *ctx )
 363 {
 364    GLuint u;
 365
 366    ctx->Texture._TexMatEnabled = 0x0;
 367
 368    for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
 369       ASSERT(u < Elements(ctx->TextureMatrixStack));
 370       if (_math_matrix_is_dirty(ctx->TextureMatrixStack[u].Top)) {
 371          _math_matrix_analyse( ctx->TextureMatrixStack[u].Top );
 372
 373          if (ctx->Texture.Unit[u]._ReallyEnabled &&
 374              ctx->TextureMatrixStack[u].Top->type != MATRIX_IDENTITY)
 375             ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(u);
 376       }
 377    }
 378 }
 379
 380
 381 /**
 382  * Examine texture unit's combine/env state to update derived state.
 383  */
 384 static void
 385 update_tex_combine(struct gl_context *ctx, struct gl_texture_unit *texUnit)
 386 {
 387    struct gl_tex_env_combine_state *combine;
 388
 389    /* No combiners will apply to this. */
 390    if (texUnit->_Current->Target == GL_TEXTURE_BUFFER)
 391       return;
 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       if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL_EXT) {
 406          format = texObj->DepthMode;
 407       }
 408       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 409       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 410    }
 411
 412    combine = texUnit->_CurrentCombine;
 413
 414    /* Determine number of source RGB terms in the combiner function */
 415    switch (combine->ModeRGB) {
 416    case GL_REPLACE:
 417       combine->_NumArgsRGB = 1;
 418       break;
 419    case GL_ADD:
 420    case GL_ADD_SIGNED:
 421       if (texUnit->EnvMode == GL_COMBINE4_NV)
 422          combine->_NumArgsRGB = 4;
 423       else
 424          combine->_NumArgsRGB = 2;
 425       break;
 426    case GL_MODULATE:
 427    case GL_SUBTRACT:
 428    case GL_DOT3_RGB:
 429    case GL_DOT3_RGBA:
 430    case GL_DOT3_RGB_EXT:
 431    case GL_DOT3_RGBA_EXT:
 432       combine->_NumArgsRGB = 2;
 433       break;
 434    case GL_INTERPOLATE:
 435    case GL_MODULATE_ADD_ATI:
 436    case GL_MODULATE_SIGNED_ADD_ATI:
 437    case GL_MODULATE_SUBTRACT_ATI:
 438       combine->_NumArgsRGB = 3;
 439       break;
 440    case GL_BUMP_ENVMAP_ATI:
 441       /* no real arguments for this case */
 442       combine->_NumArgsRGB = 0;
 443       break;
 444    default:
 445       combine->_NumArgsRGB = 0;
 446       _mesa_problem(ctx, "invalid RGB combine mode in update_texture_state");
 447       return;
 448    }
 449
 450    /* Determine number of source Alpha terms in the combiner function */
 451    switch (combine->ModeA) {
 452    case GL_REPLACE:
 453       combine->_NumArgsA = 1;
 454       break;
 455    case GL_ADD:
 456    case GL_ADD_SIGNED:
 457       if (texUnit->EnvMode == GL_COMBINE4_NV)
 458          combine->_NumArgsA = 4;
 459       else
 460          combine->_NumArgsA = 2;
 461       break;
 462    case GL_MODULATE:
 463    case GL_SUBTRACT:
 464       combine->_NumArgsA = 2;
 465       break;
 466    case GL_INTERPOLATE:
 467    case GL_MODULATE_ADD_ATI:
 468    case GL_MODULATE_SIGNED_ADD_ATI:
 469    case GL_MODULATE_SUBTRACT_ATI:
 470       combine->_NumArgsA = 3;
 471       break;
 472    default:
 473       combine->_NumArgsA = 0;
 474       _mesa_problem(ctx, "invalid Alpha combine mode in update_texture_state");
 475       break;
 476    }
 477 }
 478
 479 static void
 480 update_texgen(struct gl_context *ctx)
 481 {
 482    GLuint unit;
 483
 484    /* Setup texgen for those texture coordinate sets that are in use */
 485    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 486       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 487
 488       texUnit->_GenFlags = 0x0;
 489
 490       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 491          continue;
 492
 493       if (texUnit->TexGenEnabled) {
 494          if (texUnit->TexGenEnabled & S_BIT) {
 495             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 496          }
 497          if (texUnit->TexGenEnabled & T_BIT) {
 498             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 499          }
 500          if (texUnit->TexGenEnabled & R_BIT) {
 501             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 502          }
 503          if (texUnit->TexGenEnabled & Q_BIT) {
 504             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 505          }
 506
 507          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 508          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 509       }
 510
 511       ASSERT(unit < Elements(ctx->TextureMatrixStack));
 512       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 513          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 514    }
 515 }
 516
 517 /**
 518  * \note This routine refers to derived texture matrix values to
 519  * compute the ENABLE_TEXMAT flags, but is only called on
 520  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 521  * flags are updated by _mesa_update_texture_matrices, above.
 522  *
 523  * \param ctx GL context.
 524  */
 525 static void
 526 update_texture_state( struct gl_context *ctx )
 527 {
 528    GLuint unit;
 529    struct gl_program *fprog = NULL;
 530    struct gl_program *vprog = NULL;
 531    GLbitfield enabledFragUnits = 0x0;
 532
 533    if (ctx->Shader.CurrentVertexProgram &&
 534        ctx->Shader.CurrentVertexProgram->LinkStatus) {
 535       vprog = ctx->Shader.CurrentVertexProgram->_LinkedShaders[MESA_SHADER_VERTEX]->Program;
 536    }
 537
 538    if (ctx->Shader.CurrentFragmentProgram &&
 539        ctx->Shader.CurrentFragmentProgram->LinkStatus) {
 540       fprog = ctx->Shader.CurrentFragmentProgram->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program;
 541    }
 542    else if (ctx->FragmentProgram._Enabled) {
 543       fprog = &ctx->FragmentProgram.Current->Base;
 544    }
 545
 546    /* FINISHME: Geometry shader texture accesses should also be considered
 547     * FINISHME: here.
 548     */
 549
 550    /* TODO: only set this if there are actual changes */
 551    ctx->NewState |= _NEW_TEXTURE;
 552
 553    ctx->Texture._EnabledUnits = 0x0;
 554    ctx->Texture._GenFlags = 0x0;
 555    ctx->Texture._TexMatEnabled = 0x0;
 556    ctx->Texture._TexGenEnabled = 0x0;
 557
 558    /*
 559     * Update texture unit state.
 560     */
 561    for (unit = 0; unit < ctx->Const.MaxCombinedTextureImageUnits; unit++) {
 562       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 563       GLbitfield enabledVertTargets = 0x0;
 564       GLbitfield enabledFragTargets = 0x0;
 565       GLbitfield enabledTargets = 0x0;
 566       GLuint texIndex;
 567
 568       /* Get the bitmask of texture target enables.
 569        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 570        * which texture targets are enabled (fixed function) or referenced
 571        * by a fragment program/program.  When multiple flags are set, we'll
 572        * settle on the one with highest priority (see below).
 573        */
 574       if (vprog) {
 575          enabledVertTargets |= vprog->TexturesUsed[unit];
 576       }
 577
 578       if (fprog) {
 579          enabledFragTargets |= fprog->TexturesUsed[unit];
 580       }
 581       else {
 582          /* fixed-function fragment program */
 583          enabledFragTargets |= texUnit->Enabled;
 584       }
 585
 586       enabledTargets = enabledVertTargets | enabledFragTargets;
 587
 588       texUnit->_ReallyEnabled = 0x0;
 589
 590       if (enabledTargets == 0x0) {
 591          /* neither vertex nor fragment processing uses this unit */
 592          continue;
 593       }
 594
 595       /* Look for the highest priority texture target that's enabled (or used
 596        * by the vert/frag shaders) and "complete".  That's the one we'll use
 597        * for texturing.
 598        *
 599        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 600        */
 601       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 602          if (enabledTargets & (1 << texIndex)) {
 603             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 604             struct gl_sampler_object *sampler = texUnit->Sampler ?
 605                texUnit->Sampler : &texObj->Sampler;
 606
 607             if (!_mesa_is_texture_complete(texObj, sampler)) {
 608                _mesa_test_texobj_completeness(ctx, texObj);
 609             }
 610             if (_mesa_is_texture_complete(texObj, sampler)) {
 611                texUnit->_ReallyEnabled = 1 << texIndex;
 612                _mesa_reference_texobj(&texUnit->_Current, texObj);
 613                break;
 614             }
 615          }
 616       }
 617
 618       if (!texUnit->_ReallyEnabled) {
 619          if (fprog) {
 620             /* If we get here it means the shader is expecting a texture
 621              * object, but there isn't one (or it's incomplete).  Use the
 622              * fallback texture.
 623              */
 624             struct gl_texture_object *texObj;
 625             gl_texture_index texTarget;
 626
 627             texTarget = (gl_texture_index) (ffs(enabledTargets) - 1);
 628             texObj = _mesa_get_fallback_texture(ctx, texTarget);
 629
 630             assert(texObj);
 631             if (!texObj) {
 632                /* invalid fallback texture: don't enable the texture unit */
 633                continue;
 634             }
 635
 636             _mesa_reference_texobj(&texUnit->_Current, texObj);
 637             texUnit->_ReallyEnabled = 1 << texTarget;
 638          }
 639          else {
 640             /* fixed-function: texture unit is really disabled */
 641             continue;
 642          }
 643       }
 644
 645       /* if we get here, we know this texture unit is enabled */
 646
 647       ctx->Texture._EnabledUnits |= (1 << unit);
 648
 649       if (enabledFragTargets)
 650          enabledFragUnits |= (1 << unit);
 651
 652       if (!fprog)
 653          update_tex_combine(ctx, texUnit);
 654    }
 655
 656
 657    /* Determine which texture coordinate sets are actually needed */
 658    if (fprog) {
 659       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 660       ctx->Texture._EnabledCoordUnits
 661          = (fprog->InputsRead >> VARYING_SLOT_TEX0) & coordMask;
 662    }
 663    else {
 664       ctx->Texture._EnabledCoordUnits = enabledFragUnits;
 665    }
 666
 667    if (!fprog || !vprog)
 668       update_texgen(ctx);
 669 }
 670
 671
 672 /**
 673  * Update texture-related derived state.
 674  */
 675 void
 676 _mesa_update_texture( struct gl_context *ctx, GLuint new_state )
 677 {
 678    if (new_state & _NEW_TEXTURE_MATRIX)
 679       update_texture_matrices( ctx );
 680
 681    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 682       update_texture_state( ctx );
 683 }
 684
 685
 686 /**********************************************************************/
 687 /*****                      Initialization                        *****/
 688 /**********************************************************************/
 689
 690 /**
 691  * Allocate the proxy textures for the given context.
 692  *
 693  * \param ctx the context to allocate proxies for.
 694  *
 695  * \return GL_TRUE on success, or GL_FALSE on failure
 696  *
 697  * If run out of memory part way through the allocations, clean up and return
 698  * GL_FALSE.
 699  */
 700 static GLboolean
 701 alloc_proxy_textures( struct gl_context *ctx )
 702 {
 703    /* NOTE: these values must be in the same order as the TEXTURE_x_INDEX
 704     * values!
 705     */
 706    static const GLenum targets[] = {
 707       GL_TEXTURE_2D_MULTISAMPLE,
 708       GL_TEXTURE_2D_MULTISAMPLE_ARRAY,
 709       GL_TEXTURE_CUBE_MAP_ARRAY,
 710       GL_TEXTURE_BUFFER,
 711       GL_TEXTURE_2D_ARRAY_EXT,
 712       GL_TEXTURE_1D_ARRAY_EXT,
 713       GL_TEXTURE_EXTERNAL_OES,
 714       GL_TEXTURE_CUBE_MAP_ARB,
 715       GL_TEXTURE_3D,
 716       GL_TEXTURE_RECTANGLE_NV,
 717       GL_TEXTURE_2D,
 718       GL_TEXTURE_1D,
 719    };
 720    GLint tgt;
 721
 722    STATIC_ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 723    assert(targets[TEXTURE_2D_INDEX] == GL_TEXTURE_2D);
 724    assert(targets[TEXTURE_CUBE_INDEX] == GL_TEXTURE_CUBE_MAP);
 725
 726    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 727       if (!(ctx->Texture.ProxyTex[tgt]
 728             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 729          /* out of memory, free what we did allocate */
 730          while (--tgt >= 0) {
 731             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 732          }
 733          return GL_FALSE;
 734       }
 735    }
 736
 737    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 738    return GL_TRUE;
 739 }
 740
 741
 742 /**
 743  * Initialize a texture unit.
 744  *
 745  * \param ctx GL context.
 746  * \param unit texture unit number to be initialized.
 747  */
 748 static void
 749 init_texture_unit( struct gl_context *ctx, GLuint unit )
 750 {
 751    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 752    GLuint tex;
 753
 754    texUnit->EnvMode = GL_MODULATE;
 755    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 756
 757    texUnit->Combine = default_combine_state;
 758    texUnit->_EnvMode = default_combine_state;
 759    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 760    texUnit->BumpTarget = GL_TEXTURE0;
 761
 762    texUnit->TexGenEnabled = 0x0;
 763    texUnit->GenS.Mode = GL_EYE_LINEAR;
 764    texUnit->GenT.Mode = GL_EYE_LINEAR;
 765    texUnit->GenR.Mode = GL_EYE_LINEAR;
 766    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 767    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 768    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 769    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 770    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 771
 772    /* Yes, these plane coefficients are correct! */
 773    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 774    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 775    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 776    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 777    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 778    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 779    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 780    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 781
 782    /* no mention of this in spec, but maybe id matrix expected? */
 783    ASSIGN_4V( texUnit->RotMatrix, 1.0, 0.0, 0.0, 1.0 );
 784
 785    /* initialize current texture object ptrs to the shared default objects */
 786    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 787       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 788                              ctx->Shared->DefaultTex[tex]);
 789    }
 790 }
 791
 792
 793 /**
 794  * Initialize texture state for the given context.
 795  */
 796 GLboolean
 797 _mesa_init_texture(struct gl_context *ctx)
 798 {
 799    GLuint u;
 800
 801    /* Texture group */
 802    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 803    ctx->Texture._EnabledUnits = 0x0;
 804
 805    for (u = 0; u < Elements(ctx->Texture.Unit); u++)
 806       init_texture_unit(ctx, u);
 807
 808    /* After we're done initializing the context's texture state the default
 809     * texture objects' refcounts should be at least
 810     * MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1.
 811     */
 812    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 813           >= MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1);
 814
 815    /* Allocate proxy textures */
 816    if (!alloc_proxy_textures( ctx ))
 817       return GL_FALSE;
 818
 819    /* GL_ARB_texture_buffer_object */
 820    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject,
 821                                  ctx->Shared->NullBufferObj);
 822
 823    return GL_TRUE;
 824 }
 825
 826
 827 /**
 828  * Free dynamically-allocted texture data attached to the given context.
 829  */
 830 void
 831 _mesa_free_texture_data(struct gl_context *ctx)
 832 {
 833    GLuint u, tgt;
 834
 835    /* unreference current textures */
 836    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 837       /* The _Current texture could account for another reference */
 838       _mesa_reference_texobj(&ctx->Texture.Unit[u]._Current, NULL);
 839
 840       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 841          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 842       }
 843    }
 844
 845    /* Free proxy texture objects */
 846    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 847       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 848
 849    /* GL_ARB_texture_buffer_object */
 850    _mesa_reference_buffer_object(ctx, &ctx->Texture.BufferObject, NULL);
 851
 852    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 853       _mesa_reference_sampler_object(ctx, &ctx->Texture.Unit[u].Sampler, NULL);
 854    }
 855 }
 856
 857
 858 /**
 859  * Update the default texture objects in the given context to reference those
 860  * specified in the shared state and release those referencing the old
 861  * shared state.
 862  */
 863 void
 864 _mesa_update_default_objects_texture(struct gl_context *ctx)
 865 {
 866    GLuint u, tex;
 867
 868    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 869       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 870       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 871          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 872                                 ctx->Shared->DefaultTex[tex]);
 873       }
 874    }
 875 }