src/mesa/main/texstate.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.5
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file texstate.c
  27  *
  28  * Texture state handling.
  29  */
  30
  31 #include "glheader.h"
  32 #include "mfeatures.h"
  33 #include "colormac.h"
  34 #include "colortab.h"
  35 #include "context.h"
  36 #include "enums.h"
  37 #include "macros.h"
  38 #include "texobj.h"
  39 #include "teximage.h"
  40 #include "texstate.h"
  41 #include "mtypes.h"
  42
  43
  44
  45 /**
  46  * Default texture combine environment state.  This is used to initialize
  47  * a context's texture units and as the basis for converting "classic"
  48  * texture environmnets to ARB_texture_env_combine style values.
  49  */
  50 static const struct gl_tex_env_combine_state default_combine_state = {
  51    GL_MODULATE, GL_MODULATE,
  52    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  53    { GL_TEXTURE, GL_PREVIOUS, GL_CONSTANT, GL_CONSTANT },
  54    { GL_SRC_COLOR, GL_SRC_COLOR, GL_SRC_ALPHA, GL_SRC_ALPHA },
  55    { GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA, GL_SRC_ALPHA },
  56    0, 0,
  57    2, 2
  58 };
  59
  60
  61
  62 /**
  63  * Used by glXCopyContext to copy texture state from one context to another.
  64  */
  65 void
  66 _mesa_copy_texture_state( const 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    dst->Texture.SharedPalette = src->Texture.SharedPalette;
  78
  79    /* per-unit state */
  80    for (u = 0; u < src->Const.MaxCombinedTextureImageUnits; u++) {
  81       dst->Texture.Unit[u].Enabled = src->Texture.Unit[u].Enabled;
  82       dst->Texture.Unit[u].EnvMode = src->Texture.Unit[u].EnvMode;
  83       COPY_4V(dst->Texture.Unit[u].EnvColor, src->Texture.Unit[u].EnvColor);
  84       dst->Texture.Unit[u].TexGenEnabled = src->Texture.Unit[u].TexGenEnabled;
  85       dst->Texture.Unit[u].GenS = src->Texture.Unit[u].GenS;
  86       dst->Texture.Unit[u].GenT = src->Texture.Unit[u].GenT;
  87       dst->Texture.Unit[u].GenR = src->Texture.Unit[u].GenR;
  88       dst->Texture.Unit[u].GenQ = src->Texture.Unit[u].GenQ;
  89       dst->Texture.Unit[u].LodBias = src->Texture.Unit[u].LodBias;
  90
  91       /* GL_EXT_texture_env_combine */
  92       dst->Texture.Unit[u].Combine = src->Texture.Unit[u].Combine;
  93
  94       /* GL_ATI_envmap_bumpmap - need this? */
  95       dst->Texture.Unit[u].BumpTarget = src->Texture.Unit[u].BumpTarget;
  96       COPY_4V(dst->Texture.Unit[u].RotMatrix, src->Texture.Unit[u].RotMatrix);
  97
  98       /*
  99        * XXX strictly speaking, we should compare texture names/ids and
 100        * bind textures in the dest context according to id.  For now, only
 101        * copy bindings if the contexts share the same pool of textures to
 102        * avoid refcounting bugs.
 103        */
 104       if (dst->Shared == src->Shared) {
 105          /* copy texture object bindings, not contents of texture objects */
 106          _mesa_lock_context_textures(dst);
 107
 108          for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 109             _mesa_reference_texobj(&dst->Texture.Unit[u].CurrentTex[tex],
 110                                    src->Texture.Unit[u].CurrentTex[tex]);
 111          }
 112          _mesa_unlock_context_textures(dst);
 113       }
 114    }
 115 }
 116
 117
 118 /*
 119  * For debugging
 120  */
 121 void
 122 _mesa_print_texunit_state( struct gl_context *ctx, GLuint unit )
 123 {
 124    const struct gl_texture_unit *texUnit = ctx->Texture.Unit + unit;
 125    printf("Texture Unit %d\n", unit);
 126    printf("  GL_TEXTURE_ENV_MODE = %s\n", _mesa_lookup_enum_by_nr(texUnit->EnvMode));
 127    printf("  GL_COMBINE_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeRGB));
 128    printf("  GL_COMBINE_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.ModeA));
 129    printf("  GL_SOURCE0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[0]));
 130    printf("  GL_SOURCE1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[1]));
 131    printf("  GL_SOURCE2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceRGB[2]));
 132    printf("  GL_SOURCE0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[0]));
 133    printf("  GL_SOURCE1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[1]));
 134    printf("  GL_SOURCE2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.SourceA[2]));
 135    printf("  GL_OPERAND0_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[0]));
 136    printf("  GL_OPERAND1_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[1]));
 137    printf("  GL_OPERAND2_RGB = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandRGB[2]));
 138    printf("  GL_OPERAND0_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[0]));
 139    printf("  GL_OPERAND1_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[1]));
 140    printf("  GL_OPERAND2_ALPHA = %s\n", _mesa_lookup_enum_by_nr(texUnit->Combine.OperandA[2]));
 141    printf("  GL_RGB_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftRGB);
 142    printf("  GL_ALPHA_SCALE = %d\n", 1 << texUnit->Combine.ScaleShiftA);
 143    printf("  GL_TEXTURE_ENV_COLOR = (%f, %f, %f, %f)\n", texUnit->EnvColor[0], texUnit->EnvColor[1], texUnit->EnvColor[2], texUnit->EnvColor[3]);
 144 }
 145
 146
 147
 148 /**********************************************************************/
 149 /*                       Texture Environment                          */
 150 /**********************************************************************/
 151
 152 /**
 153  * Convert "classic" texture environment to ARB_texture_env_combine style
 154  * environments.
 155  *
 156  * \param state  texture_env_combine state vector to be filled-in.
 157  * \param mode   Classic texture environment mode (i.e., \c GL_REPLACE,
 158  *               \c GL_BLEND, \c GL_DECAL, etc.).
 159  * \param texBaseFormat  Base format of the texture associated with the
 160  *               texture unit.
 161  */
 162 static void
 163 calculate_derived_texenv( struct gl_tex_env_combine_state *state,
 164                           GLenum mode, GLenum texBaseFormat )
 165 {
 166    GLenum mode_rgb;
 167    GLenum mode_a;
 168
 169    *state = default_combine_state;
 170
 171    switch (texBaseFormat) {
 172    case GL_ALPHA:
 173       state->SourceRGB[0] = GL_PREVIOUS;
 174       break;
 175
 176    case GL_LUMINANCE_ALPHA:
 177    case GL_INTENSITY:
 178    case GL_RGBA:
 179       break;
 180
 181    case GL_LUMINANCE:
 182    case GL_RED:
 183    case GL_RG:
 184    case GL_RGB:
 185    case GL_YCBCR_MESA:
 186    case GL_DUDV_ATI:
 187       state->SourceA[0] = GL_PREVIOUS;
 188       break;
 189
 190    default:
 191       _mesa_problem(NULL,
 192                     "Invalid texBaseFormat 0x%x in calculate_derived_texenv",
 193                     texBaseFormat);
 194       return;
 195    }
 196
 197    if (mode == GL_REPLACE_EXT)
 198       mode = GL_REPLACE;
 199
 200    switch (mode) {
 201    case GL_REPLACE:
 202    case GL_MODULATE:
 203       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : mode;
 204       mode_a   = mode;
 205       break;
 206
 207    case GL_DECAL:
 208       mode_rgb = GL_INTERPOLATE;
 209       mode_a   = GL_REPLACE;
 210
 211       state->SourceA[0] = GL_PREVIOUS;
 212
 213       /* Having alpha / luminance / intensity textures replace using the
 214        * incoming fragment color matches the definition in NV_texture_shader.
 215        * The 1.5 spec simply marks these as "undefined".
 216        */
 217       switch (texBaseFormat) {
 218       case GL_ALPHA:
 219       case GL_LUMINANCE:
 220       case GL_LUMINANCE_ALPHA:
 221       case GL_INTENSITY:
 222          state->SourceRGB[0] = GL_PREVIOUS;
 223          break;
 224       case GL_RED:
 225       case GL_RG:
 226       case GL_RGB:
 227       case GL_YCBCR_MESA:
 228       case GL_DUDV_ATI:
 229          mode_rgb = GL_REPLACE;
 230          break;
 231       case GL_RGBA:
 232          state->SourceRGB[2] = GL_TEXTURE;
 233          break;
 234       }
 235       break;
 236
 237    case GL_BLEND:
 238       mode_rgb = GL_INTERPOLATE;
 239       mode_a   = GL_MODULATE;
 240
 241       switch (texBaseFormat) {
 242       case GL_ALPHA:
 243          mode_rgb = GL_REPLACE;
 244          break;
 245       case GL_INTENSITY:
 246          mode_a = GL_INTERPOLATE;
 247          state->SourceA[0] = GL_CONSTANT;
 248          state->OperandA[2] = GL_SRC_ALPHA;
 249          /* FALLTHROUGH */
 250       case GL_LUMINANCE:
 251       case GL_RED:
 252       case GL_RG:
 253       case GL_RGB:
 254       case GL_LUMINANCE_ALPHA:
 255       case GL_RGBA:
 256       case GL_YCBCR_MESA:
 257       case GL_DUDV_ATI:
 258          state->SourceRGB[2] = GL_TEXTURE;
 259          state->SourceA[2]   = GL_TEXTURE;
 260          state->SourceRGB[0] = GL_CONSTANT;
 261          state->OperandRGB[2] = GL_SRC_COLOR;
 262          break;
 263       }
 264       break;
 265
 266    case GL_ADD:
 267       mode_rgb = (texBaseFormat == GL_ALPHA) ? GL_REPLACE : GL_ADD;
 268       mode_a   = (texBaseFormat == GL_INTENSITY) ? GL_ADD : GL_MODULATE;
 269       break;
 270
 271    default:
 272       _mesa_problem(NULL,
 273                     "Invalid texture env mode 0x%x in calculate_derived_texenv",
 274                     mode);
 275       return;
 276    }
 277
 278    state->ModeRGB = (state->SourceRGB[0] != GL_PREVIOUS)
 279        ? mode_rgb : GL_REPLACE;
 280    state->ModeA   = (state->SourceA[0]   != GL_PREVIOUS)
 281        ? mode_a   : GL_REPLACE;
 282 }
 283
 284
 285
 286
 287 /* GL_ARB_multitexture */
 288 void GLAPIENTRY
 289 _mesa_ActiveTextureARB(GLenum texture)
 290 {
 291    const GLuint texUnit = texture - GL_TEXTURE0;
 292    GLuint k;
 293    GET_CURRENT_CONTEXT(ctx);
 294
 295    /* See OpenGL spec for glActiveTexture: */
 296    k = MAX2(ctx->Const.MaxCombinedTextureImageUnits,
 297             ctx->Const.MaxTextureCoordUnits);
 298
 299    ASSERT(k <= Elements(ctx->Texture.Unit));
 300
 301    ASSERT_OUTSIDE_BEGIN_END(ctx);
 302
 303    if (MESA_VERBOSE & (VERBOSE_API|VERBOSE_TEXTURE))
 304       _mesa_debug(ctx, "glActiveTexture %s\n",
 305                   _mesa_lookup_enum_by_nr(texture));
 306
 307    if (texUnit >= k) {
 308       _mesa_error(ctx, GL_INVALID_ENUM, "glActiveTexture(texture=%s)",
 309                   _mesa_lookup_enum_by_nr(texture));
 310       return;
 311    }
 312
 313    if (ctx->Texture.CurrentUnit == texUnit)
 314       return;
 315
 316    FLUSH_VERTICES(ctx, _NEW_TEXTURE);
 317
 318    ctx->Texture.CurrentUnit = texUnit;
 319    if (ctx->Transform.MatrixMode == GL_TEXTURE) {
 320       /* update current stack pointer */
 321       ctx->CurrentStack = &ctx->TextureMatrixStack[texUnit];
 322    }
 323 }
 324
 325
 326 /* GL_ARB_multitexture */
 327 void GLAPIENTRY
 328 _mesa_ClientActiveTextureARB(GLenum texture)
 329 {
 330    GET_CURRENT_CONTEXT(ctx);
 331    GLuint texUnit = texture - GL_TEXTURE0;
 332    ASSERT_OUTSIDE_BEGIN_END(ctx);
 333
 334    if (MESA_VERBOSE & (VERBOSE_API | VERBOSE_TEXTURE))
 335       _mesa_debug(ctx, "glClientActiveTexture %s\n",
 336                   _mesa_lookup_enum_by_nr(texture));
 337
 338    if (texUnit >= ctx->Const.MaxTextureCoordUnits) {
 339       _mesa_error(ctx, GL_INVALID_ENUM, "glClientActiveTexture(texture)");
 340       return;
 341    }
 342
 343    if (ctx->Array.ActiveTexture == texUnit)
 344       return;
 345
 346    FLUSH_VERTICES(ctx, _NEW_ARRAY);
 347    ctx->Array.ActiveTexture = texUnit;
 348 }
 349
 350
 351
 352 /**********************************************************************/
 353 /*****                    State management                        *****/
 354 /**********************************************************************/
 355
 356
 357 /**
 358  * \note This routine refers to derived texture attribute values to
 359  * compute the ENABLE_TEXMAT flags, but is only called on
 360  * _NEW_TEXTURE_MATRIX.  On changes to _NEW_TEXTURE, the ENABLE_TEXMAT
 361  * flags are updated by _mesa_update_textures(), below.
 362  *
 363  * \param ctx GL context.
 364  */
 365 static void
 366 update_texture_matrices( struct gl_context *ctx )
 367 {
 368    GLuint u;
 369
 370    ctx->Texture._TexMatEnabled = 0x0;
 371
 372    for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
 373       ASSERT(u < Elements(ctx->TextureMatrixStack));
 374       if (_math_matrix_is_dirty(ctx->TextureMatrixStack[u].Top)) {
 375          _math_matrix_analyse( ctx->TextureMatrixStack[u].Top );
 376
 377          if (ctx->Texture.Unit[u]._ReallyEnabled &&
 378              ctx->TextureMatrixStack[u].Top->type != MATRIX_IDENTITY)
 379             ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(u);
 380       }
 381    }
 382 }
 383
 384
 385 /**
 386  * Examine texture unit's combine/env state to update derived state.
 387  */
 388 static void
 389 update_tex_combine(struct gl_context *ctx, struct gl_texture_unit *texUnit)
 390 {
 391    struct gl_tex_env_combine_state *combine;
 392
 393    /* Set the texUnit->_CurrentCombine field to point to the user's combiner
 394     * state, or the combiner state which is derived from traditional texenv
 395     * mode.
 396     */
 397    if (texUnit->EnvMode == GL_COMBINE ||
 398        texUnit->EnvMode == GL_COMBINE4_NV) {
 399       texUnit->_CurrentCombine = & texUnit->Combine;
 400    }
 401    else {
 402       const struct gl_texture_object *texObj = texUnit->_Current;
 403       GLenum format = texObj->Image[0][texObj->BaseLevel]->_BaseFormat;
 404       if (format == GL_COLOR_INDEX) {
 405          format = GL_RGBA;  /* a bit of a hack */
 406       }
 407       else if (format == GL_DEPTH_COMPONENT ||
 408                format == GL_DEPTH_STENCIL_EXT) {
 409          format = texObj->DepthMode;
 410       }
 411       calculate_derived_texenv(&texUnit->_EnvMode, texUnit->EnvMode, format);
 412       texUnit->_CurrentCombine = & texUnit->_EnvMode;
 413    }
 414
 415    combine = texUnit->_CurrentCombine;
 416
 417    /* Determine number of source RGB terms in the combiner function */
 418    switch (combine->ModeRGB) {
 419    case GL_REPLACE:
 420       combine->_NumArgsRGB = 1;
 421       break;
 422    case GL_ADD:
 423    case GL_ADD_SIGNED:
 424       if (texUnit->EnvMode == GL_COMBINE4_NV)
 425          combine->_NumArgsRGB = 4;
 426       else
 427          combine->_NumArgsRGB = 2;
 428       break;
 429    case GL_MODULATE:
 430    case GL_SUBTRACT:
 431    case GL_DOT3_RGB:
 432    case GL_DOT3_RGBA:
 433    case GL_DOT3_RGB_EXT:
 434    case GL_DOT3_RGBA_EXT:
 435       combine->_NumArgsRGB = 2;
 436       break;
 437    case GL_INTERPOLATE:
 438    case GL_MODULATE_ADD_ATI:
 439    case GL_MODULATE_SIGNED_ADD_ATI:
 440    case GL_MODULATE_SUBTRACT_ATI:
 441       combine->_NumArgsRGB = 3;
 442       break;
 443    case GL_BUMP_ENVMAP_ATI:
 444       /* no real arguments for this case */
 445       combine->_NumArgsRGB = 0;
 446       break;
 447    default:
 448       combine->_NumArgsRGB = 0;
 449       _mesa_problem(ctx, "invalid RGB combine mode in update_texture_state");
 450       return;
 451    }
 452
 453    /* Determine number of source Alpha terms in the combiner function */
 454    switch (combine->ModeA) {
 455    case GL_REPLACE:
 456       combine->_NumArgsA = 1;
 457       break;
 458    case GL_ADD:
 459    case GL_ADD_SIGNED:
 460       if (texUnit->EnvMode == GL_COMBINE4_NV)
 461          combine->_NumArgsA = 4;
 462       else
 463          combine->_NumArgsA = 2;
 464       break;
 465    case GL_MODULATE:
 466    case GL_SUBTRACT:
 467       combine->_NumArgsA = 2;
 468       break;
 469    case GL_INTERPOLATE:
 470    case GL_MODULATE_ADD_ATI:
 471    case GL_MODULATE_SIGNED_ADD_ATI:
 472    case GL_MODULATE_SUBTRACT_ATI:
 473       combine->_NumArgsA = 3;
 474       break;
 475    default:
 476       combine->_NumArgsA = 0;
 477       _mesa_problem(ctx, "invalid Alpha combine mode in update_texture_state");
 478       break;
 479    }
 480 }
 481
 482
 483 /**
 484  * \note This routine refers to derived texture matrix values to
 485  * compute the ENABLE_TEXMAT flags, but is only called on
 486  * _NEW_TEXTURE.  On changes to _NEW_TEXTURE_MATRIX, the ENABLE_TEXMAT
 487  * flags are updated by _mesa_update_texture_matrices, above.
 488  *
 489  * \param ctx GL context.
 490  */
 491 static void
 492 update_texture_state( struct gl_context *ctx )
 493 {
 494    GLuint unit;
 495    struct gl_fragment_program *fprog = NULL;
 496    struct gl_vertex_program *vprog = NULL;
 497    GLbitfield enabledFragUnits = 0x0;
 498
 499    if (ctx->Shader.CurrentVertexProgram &&
 500        ctx->Shader.CurrentVertexProgram->LinkStatus) {
 501       vprog = ctx->Shader.CurrentVertexProgram->VertexProgram;
 502    } else if (ctx->VertexProgram._Enabled) {
 503       /* XXX enable this if/when non-shader vertex programs get
 504        * texture fetches:
 505        vprog = ctx->VertexProgram.Current;
 506        */
 507    }
 508
 509    if (ctx->Shader.CurrentFragmentProgram &&
 510        ctx->Shader.CurrentFragmentProgram->LinkStatus) {
 511       fprog = ctx->Shader.CurrentFragmentProgram->FragmentProgram;
 512    }
 513    else if (ctx->FragmentProgram._Enabled) {
 514       fprog = ctx->FragmentProgram.Current;
 515    }
 516
 517    /* FINISHME: Geometry shader texture accesses should also be considered
 518     * FINISHME: here.
 519     */
 520
 521    /* TODO: only set this if there are actual changes */
 522    ctx->NewState |= _NEW_TEXTURE;
 523
 524    ctx->Texture._EnabledUnits = 0x0;
 525    ctx->Texture._GenFlags = 0x0;
 526    ctx->Texture._TexMatEnabled = 0x0;
 527    ctx->Texture._TexGenEnabled = 0x0;
 528
 529    /*
 530     * Update texture unit state.
 531     */
 532    for (unit = 0; unit < ctx->Const.MaxCombinedTextureImageUnits; unit++) {
 533       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 534       GLbitfield enabledVertTargets = 0x0;
 535       GLbitfield enabledFragTargets = 0x0;
 536       GLbitfield enabledTargets = 0x0;
 537       GLuint texIndex;
 538
 539       /* Get the bitmask of texture target enables.
 540        * enableBits will be a mask of the TEXTURE_*_BIT flags indicating
 541        * which texture targets are enabled (fixed function) or referenced
 542        * by a fragment program/program.  When multiple flags are set, we'll
 543        * settle on the one with highest priority (see below).
 544        */
 545       if (vprog) {
 546          enabledVertTargets |= vprog->Base.TexturesUsed[unit];
 547       }
 548
 549       if (fprog) {
 550          enabledFragTargets |= fprog->Base.TexturesUsed[unit];
 551       }
 552       else {
 553          /* fixed-function fragment program */
 554          enabledFragTargets |= texUnit->Enabled;
 555       }
 556
 557       enabledTargets = enabledVertTargets | enabledFragTargets;
 558
 559       texUnit->_ReallyEnabled = 0x0;
 560
 561       if (enabledTargets == 0x0) {
 562          /* neither vertex nor fragment processing uses this unit */
 563          continue;
 564       }
 565
 566       /* Look for the highest priority texture target that's enabled (or used
 567        * by the vert/frag shaders) and "complete".  That's the one we'll use
 568        * for texturing.  If we're using vert/frag program we're guaranteed
 569        * that bitcount(enabledBits) <= 1.
 570        * Note that the TEXTURE_x_INDEX values are in high to low priority.
 571        */
 572       for (texIndex = 0; texIndex < NUM_TEXTURE_TARGETS; texIndex++) {
 573          if (enabledTargets & (1 << texIndex)) {
 574             struct gl_texture_object *texObj = texUnit->CurrentTex[texIndex];
 575             if (!texObj->_Complete) {
 576                _mesa_test_texobj_completeness(ctx, texObj);
 577             }
 578             if (texObj->_Complete) {
 579                texUnit->_ReallyEnabled = 1 << texIndex;
 580                _mesa_reference_texobj(&texUnit->_Current, texObj);
 581                break;
 582             }
 583          }
 584       }
 585
 586       if (!texUnit->_ReallyEnabled) {
 587          if (fprog) {
 588             /* If we get here it means the shader is expecting a texture
 589              * object, but there isn't one (or it's incomplete).  Use the
 590              * fallback texture.
 591              */
 592             struct gl_texture_object *texObj = _mesa_get_fallback_texture(ctx);
 593             texUnit->_ReallyEnabled = 1 << TEXTURE_2D_INDEX;
 594             _mesa_reference_texobj(&texUnit->_Current, texObj);
 595          }
 596          else {
 597             /* fixed-function: texture unit is really disabled */
 598             continue;
 599          }
 600       }
 601
 602       /* if we get here, we know this texture unit is enabled */
 603
 604       ctx->Texture._EnabledUnits |= (1 << unit);
 605
 606       if (enabledFragTargets)
 607          enabledFragUnits |= (1 << unit);
 608
 609       update_tex_combine(ctx, texUnit);
 610    }
 611
 612
 613    /* Determine which texture coordinate sets are actually needed */
 614    if (fprog) {
 615       const GLuint coordMask = (1 << MAX_TEXTURE_COORD_UNITS) - 1;
 616       ctx->Texture._EnabledCoordUnits
 617          = (fprog->Base.InputsRead >> FRAG_ATTRIB_TEX0) & coordMask;
 618    }
 619    else {
 620       ctx->Texture._EnabledCoordUnits = enabledFragUnits;
 621    }
 622
 623    /* Setup texgen for those texture coordinate sets that are in use */
 624    for (unit = 0; unit < ctx->Const.MaxTextureCoordUnits; unit++) {
 625       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 626
 627       texUnit->_GenFlags = 0x0;
 628
 629       if (!(ctx->Texture._EnabledCoordUnits & (1 << unit)))
 630          continue;
 631
 632       if (texUnit->TexGenEnabled) {
 633          if (texUnit->TexGenEnabled & S_BIT) {
 634             texUnit->_GenFlags |= texUnit->GenS._ModeBit;
 635          }
 636          if (texUnit->TexGenEnabled & T_BIT) {
 637             texUnit->_GenFlags |= texUnit->GenT._ModeBit;
 638          }
 639          if (texUnit->TexGenEnabled & R_BIT) {
 640             texUnit->_GenFlags |= texUnit->GenR._ModeBit;
 641          }
 642          if (texUnit->TexGenEnabled & Q_BIT) {
 643             texUnit->_GenFlags |= texUnit->GenQ._ModeBit;
 644          }
 645
 646          ctx->Texture._TexGenEnabled |= ENABLE_TEXGEN(unit);
 647          ctx->Texture._GenFlags |= texUnit->_GenFlags;
 648       }
 649
 650       ASSERT(unit < Elements(ctx->TextureMatrixStack));
 651       if (ctx->TextureMatrixStack[unit].Top->type != MATRIX_IDENTITY)
 652          ctx->Texture._TexMatEnabled |= ENABLE_TEXMAT(unit);
 653    }
 654 }
 655
 656
 657 /**
 658  * Update texture-related derived state.
 659  */
 660 void
 661 _mesa_update_texture( struct gl_context *ctx, GLuint new_state )
 662 {
 663    if (new_state & _NEW_TEXTURE_MATRIX)
 664       update_texture_matrices( ctx );
 665
 666    if (new_state & (_NEW_TEXTURE | _NEW_PROGRAM))
 667       update_texture_state( ctx );
 668 }
 669
 670
 671 /**********************************************************************/
 672 /*****                      Initialization                        *****/
 673 /**********************************************************************/
 674
 675 /**
 676  * Allocate the proxy textures for the given context.
 677  *
 678  * \param ctx the context to allocate proxies for.
 679  *
 680  * \return GL_TRUE on success, or GL_FALSE on failure
 681  *
 682  * If run out of memory part way through the allocations, clean up and return
 683  * GL_FALSE.
 684  */
 685 static GLboolean
 686 alloc_proxy_textures( struct gl_context *ctx )
 687 {
 688    static const GLenum targets[] = {
 689       GL_TEXTURE_1D,
 690       GL_TEXTURE_2D,
 691       GL_TEXTURE_3D,
 692       GL_TEXTURE_CUBE_MAP_ARB,
 693       GL_TEXTURE_RECTANGLE_NV,
 694       GL_TEXTURE_1D_ARRAY_EXT,
 695       GL_TEXTURE_2D_ARRAY_EXT
 696    };
 697    GLint tgt;
 698
 699    ASSERT(Elements(targets) == NUM_TEXTURE_TARGETS);
 700
 701    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 702       if (!(ctx->Texture.ProxyTex[tgt]
 703             = ctx->Driver.NewTextureObject(ctx, 0, targets[tgt]))) {
 704          /* out of memory, free what we did allocate */
 705          while (--tgt >= 0) {
 706             ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 707          }
 708          return GL_FALSE;
 709       }
 710    }
 711
 712    assert(ctx->Texture.ProxyTex[0]->RefCount == 1); /* sanity check */
 713    return GL_TRUE;
 714 }
 715
 716
 717 /**
 718  * Initialize a texture unit.
 719  *
 720  * \param ctx GL context.
 721  * \param unit texture unit number to be initialized.
 722  */
 723 static void
 724 init_texture_unit( struct gl_context *ctx, GLuint unit )
 725 {
 726    struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
 727    GLuint tex;
 728
 729    texUnit->EnvMode = GL_MODULATE;
 730    ASSIGN_4V( texUnit->EnvColor, 0.0, 0.0, 0.0, 0.0 );
 731
 732    texUnit->Combine = default_combine_state;
 733    texUnit->_EnvMode = default_combine_state;
 734    texUnit->_CurrentCombine = & texUnit->_EnvMode;
 735    texUnit->BumpTarget = GL_TEXTURE0;
 736
 737    texUnit->TexGenEnabled = 0x0;
 738    texUnit->GenS.Mode = GL_EYE_LINEAR;
 739    texUnit->GenT.Mode = GL_EYE_LINEAR;
 740    texUnit->GenR.Mode = GL_EYE_LINEAR;
 741    texUnit->GenQ.Mode = GL_EYE_LINEAR;
 742    texUnit->GenS._ModeBit = TEXGEN_EYE_LINEAR;
 743    texUnit->GenT._ModeBit = TEXGEN_EYE_LINEAR;
 744    texUnit->GenR._ModeBit = TEXGEN_EYE_LINEAR;
 745    texUnit->GenQ._ModeBit = TEXGEN_EYE_LINEAR;
 746
 747    /* Yes, these plane coefficients are correct! */
 748    ASSIGN_4V( texUnit->GenS.ObjectPlane, 1.0, 0.0, 0.0, 0.0 );
 749    ASSIGN_4V( texUnit->GenT.ObjectPlane, 0.0, 1.0, 0.0, 0.0 );
 750    ASSIGN_4V( texUnit->GenR.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 751    ASSIGN_4V( texUnit->GenQ.ObjectPlane, 0.0, 0.0, 0.0, 0.0 );
 752    ASSIGN_4V( texUnit->GenS.EyePlane, 1.0, 0.0, 0.0, 0.0 );
 753    ASSIGN_4V( texUnit->GenT.EyePlane, 0.0, 1.0, 0.0, 0.0 );
 754    ASSIGN_4V( texUnit->GenR.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 755    ASSIGN_4V( texUnit->GenQ.EyePlane, 0.0, 0.0, 0.0, 0.0 );
 756
 757    /* no mention of this in spec, but maybe id matrix expected? */
 758    ASSIGN_4V( texUnit->RotMatrix, 1.0, 0.0, 0.0, 1.0 );
 759
 760    /* initialize current texture object ptrs to the shared default objects */
 761    for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 762       _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 763                              ctx->Shared->DefaultTex[tex]);
 764    }
 765 }
 766
 767
 768 /**
 769  * Initialize texture state for the given context.
 770  */
 771 GLboolean
 772 _mesa_init_texture(struct gl_context *ctx)
 773 {
 774    GLuint u;
 775
 776    /* Texture group */
 777    ctx->Texture.CurrentUnit = 0;      /* multitexture */
 778    ctx->Texture._EnabledUnits = 0x0;
 779    ctx->Texture.SharedPalette = GL_FALSE;
 780    _mesa_init_colortable(&ctx->Texture.Palette);
 781
 782    for (u = 0; u < Elements(ctx->Texture.Unit); u++)
 783       init_texture_unit(ctx, u);
 784
 785    /* After we're done initializing the context's texture state the default
 786     * texture objects' refcounts should be at least
 787     * MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1.
 788     */
 789    assert(ctx->Shared->DefaultTex[TEXTURE_1D_INDEX]->RefCount
 790           >= MAX_COMBINED_TEXTURE_IMAGE_UNITS + 1);
 791
 792    /* Allocate proxy textures */
 793    if (!alloc_proxy_textures( ctx ))
 794       return GL_FALSE;
 795
 796    return GL_TRUE;
 797 }
 798
 799
 800 /**
 801  * Free dynamically-allocted texture data attached to the given context.
 802  */
 803 void
 804 _mesa_free_texture_data(struct gl_context *ctx)
 805 {
 806    GLuint u, tgt;
 807
 808    /* unreference current textures */
 809    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 810       /* The _Current texture could account for another reference */
 811       _mesa_reference_texobj(&ctx->Texture.Unit[u]._Current, NULL);
 812
 813       for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++) {
 814          _mesa_reference_texobj(&ctx->Texture.Unit[u].CurrentTex[tgt], NULL);
 815       }
 816    }
 817
 818    /* Free proxy texture objects */
 819    for (tgt = 0; tgt < NUM_TEXTURE_TARGETS; tgt++)
 820       ctx->Driver.DeleteTexture(ctx, ctx->Texture.ProxyTex[tgt]);
 821 }
 822
 823
 824 /**
 825  * Update the default texture objects in the given context to reference those
 826  * specified in the shared state and release those referencing the old
 827  * shared state.
 828  */
 829 void
 830 _mesa_update_default_objects_texture(struct gl_context *ctx)
 831 {
 832    GLuint u, tex;
 833
 834    for (u = 0; u < Elements(ctx->Texture.Unit); u++) {
 835       struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
 836       for (tex = 0; tex < NUM_TEXTURE_TARGETS; tex++) {
 837          _mesa_reference_texobj(&texUnit->CurrentTex[tex],
 838                                 ctx->Shared->DefaultTex[tex]);
 839       }
 840    }
 841 }