src/mesa/main/context.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.3
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   6  * Copyright (C) 2008  VMware, Inc.  All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 /**
  27  * \file context.c
  28  * Mesa context/visual/framebuffer management functions.
  29  * \author Brian Paul
  30  */
  31
  32 /**
  33  * \mainpage Mesa Main Module
  34  *
  35  * \section MainIntroduction Introduction
  36  *
  37  * The Mesa Main module consists of all the files in the main/ directory.
  38  * Among the features of this module are:
  39  * <UL>
  40  * <LI> Structures to represent most GL state </LI>
  41  * <LI> State set/get functions </LI>
  42  * <LI> Display lists </LI>
  43  * <LI> Texture unit, object and image handling </LI>
  44  * <LI> Matrix and attribute stacks </LI>
  45  * </UL>
  46  *
  47  * Other modules are responsible for API dispatch, vertex transformation,
  48  * point/line/triangle setup, rasterization, vertex array caching,
  49  * vertex/fragment programs/shaders, etc.
  50  *
  51  *
  52  * \section AboutDoxygen About Doxygen
  53  *
  54  * If you're viewing this information as Doxygen-generated HTML you'll
  55  * see the documentation index at the top of this page.
  56  *
  57  * The first line lists the Mesa source code modules.
  58  * The second line lists the indexes available for viewing the documentation
  59  * for each module.
  60  *
  61  * Selecting the <b>Main page</b> link will display a summary of the module
  62  * (this page).
  63  *
  64  * Selecting <b>Data Structures</b> will list all C structures.
  65  *
  66  * Selecting the <b>File List</b> link will list all the source files in
  67  * the module.
  68  * Selecting a filename will show a list of all functions defined in that file.
  69  *
  70  * Selecting the <b>Data Fields</b> link will display a list of all
  71  * documented structure members.
  72  *
  73  * Selecting the <b>Globals</b> link will display a list
  74  * of all functions, structures, global variables and macros in the module.
  75  *
  76  */
  77
  78
  79 #include "glheader.h"
  80 #include "mfeatures.h"
  81 #include "imports.h"
  82 #include "accum.h"
  83 #include "api_exec.h"
  84 #include "arrayobj.h"
  85 #include "attrib.h"
  86 #include "blend.h"
  87 #include "buffers.h"
  88 #include "bufferobj.h"
  89 #include "colortab.h"
  90 #include "context.h"
  91 #include "cpuinfo.h"
  92 #include "debug.h"
  93 #include "depth.h"
  94 #include "dlist.h"
  95 #include "eval.h"
  96 #include "enums.h"
  97 #include "extensions.h"
  98 #include "fbobject.h"
  99 #include "feedback.h"
 100 #include "fog.h"
 101 #include "framebuffer.h"
 102 #include "get.h"
 103 #include "histogram.h"
 104 #include "hint.h"
 105 #include "hash.h"
 106 #include "light.h"
 107 #include "lines.h"
 108 #include "macros.h"
 109 #include "matrix.h"
 110 #include "multisample.h"
 111 #include "pixel.h"
 112 #include "pixelstore.h"
 113 #include "points.h"
 114 #include "polygon.h"
 115 #include "queryobj.h"
 116 #if FEATURE_ARB_sync
 117 #include "syncobj.h"
 118 #endif
 119 #include "rastpos.h"
 120 #include "remap.h"
 121 #include "scissor.h"
 122 #include "shared.h"
 123 #include "simple_list.h"
 124 #include "state.h"
 125 #include "stencil.h"
 126 #include "texcompress_s3tc.h"
 127 #include "teximage.h"
 128 #include "texobj.h"
 129 #include "texstate.h"
 130 #include "mtypes.h"
 131 #include "varray.h"
 132 #include "version.h"
 133 #include "viewport.h"
 134 #include "vtxfmt.h"
 135 #include "glapi/glthread.h"
 136 #include "glapi/glapitable.h"
 137 #include "shader/program.h"
 138 #include "shader/prog_print.h"
 139 #include "shader/shader_api.h"
 140 #if FEATURE_ATI_fragment_shader
 141 #include "shader/atifragshader.h"
 142 #endif
 143 #if _HAVE_FULL_GL
 144 #include "math/m_matrix.h"
 145 #endif
 146
 147 #ifdef USE_SPARC_ASM
 148 #include "sparc/sparc.h"
 149 #endif
 150
 151 #ifndef MESA_VERBOSE
 152 int MESA_VERBOSE = 0;
 153 #endif
 154
 155 #ifndef MESA_DEBUG_FLAGS
 156 int MESA_DEBUG_FLAGS = 0;
 157 #endif
 158
 159
 160 /* ubyte -> float conversion */
 161 GLfloat _mesa_ubyte_to_float_color_tab[256];
 162
 163
 164
 165 /**
 166  * Swap buffers notification callback.
 167  *
 168  * \param ctx GL context.
 169  *
 170  * Called by window system just before swapping buffers.
 171  * We have to finish any pending rendering.
 172  */
 173 void
 174 _mesa_notifySwapBuffers(__GLcontext *ctx)
 175 {
 176    if (MESA_VERBOSE & VERBOSE_SWAPBUFFERS)
 177       _mesa_debug(ctx, "SwapBuffers\n");
 178    FLUSH_CURRENT( ctx, 0 );
 179    if (ctx->Driver.Flush) {
 180       ctx->Driver.Flush(ctx);
 181    }
 182 }
 183
 184
 185 /**********************************************************************/
 186 /** \name GL Visual allocation/destruction                            */
 187 /**********************************************************************/
 188 /*@{*/
 189
 190 /**
 191  * Allocates a GLvisual structure and initializes it via
 192  * _mesa_initialize_visual().
 193  *
 194  * \param rgbFlag GL_TRUE for RGB(A) mode, GL_FALSE for Color Index mode.
 195  * \param dbFlag double buffering
 196  * \param stereoFlag stereo buffer
 197  * \param depthBits requested bits per depth buffer value. Any value in [0, 32]
 198  * is acceptable but the actual depth type will be GLushort or GLuint as
 199  * needed.
 200  * \param stencilBits requested minimum bits per stencil buffer value
 201  * \param accumRedBits, accumGreenBits, accumBlueBits, accumAlphaBits number of bits per color component in accum buffer.
 202  * \param indexBits number of bits per pixel if \p rgbFlag is GL_FALSE
 203  * \param redBits number of bits per color component in frame buffer for RGB(A)
 204  * mode.  We always use 8 in core Mesa though.
 205  * \param greenBits same as above.
 206  * \param blueBits same as above.
 207  * \param alphaBits same as above.
 208  * \param numSamples not really used.
 209  *
 210  * \return pointer to new GLvisual or NULL if requested parameters can't be
 211  * met.
 212  *
 213  * \note Need to add params for level and numAuxBuffers (at least)
 214  */
 215 GLvisual *
 216 _mesa_create_visual( GLboolean rgbFlag,
 217                      GLboolean dbFlag,
 218                      GLboolean stereoFlag,
 219                      GLint redBits,
 220                      GLint greenBits,
 221                      GLint blueBits,
 222                      GLint alphaBits,
 223                      GLint indexBits,
 224                      GLint depthBits,
 225                      GLint stencilBits,
 226                      GLint accumRedBits,
 227                      GLint accumGreenBits,
 228                      GLint accumBlueBits,
 229                      GLint accumAlphaBits,
 230                      GLint numSamples )
 231 {
 232    GLvisual *vis = (GLvisual *) _mesa_calloc(sizeof(GLvisual));
 233    if (vis) {
 234       if (!_mesa_initialize_visual(vis, rgbFlag, dbFlag, stereoFlag,
 235                                    redBits, greenBits, blueBits, alphaBits,
 236                                    indexBits, depthBits, stencilBits,
 237                                    accumRedBits, accumGreenBits,
 238                                    accumBlueBits, accumAlphaBits,
 239                                    numSamples)) {
 240          _mesa_free(vis);
 241          return NULL;
 242       }
 243    }
 244    return vis;
 245 }
 246
 247 /**
 248  * Makes some sanity checks and fills in the fields of the
 249  * GLvisual object with the given parameters.  If the caller needs
 250  * to set additional fields, he should just probably init the whole GLvisual
 251  * object himself.
 252  * \return GL_TRUE on success, or GL_FALSE on failure.
 253  *
 254  * \sa _mesa_create_visual() above for the parameter description.
 255  */
 256 GLboolean
 257 _mesa_initialize_visual( GLvisual *vis,
 258                          GLboolean rgbFlag,
 259                          GLboolean dbFlag,
 260                          GLboolean stereoFlag,
 261                          GLint redBits,
 262                          GLint greenBits,
 263                          GLint blueBits,
 264                          GLint alphaBits,
 265                          GLint indexBits,
 266                          GLint depthBits,
 267                          GLint stencilBits,
 268                          GLint accumRedBits,
 269                          GLint accumGreenBits,
 270                          GLint accumBlueBits,
 271                          GLint accumAlphaBits,
 272                          GLint numSamples )
 273 {
 274    assert(vis);
 275
 276    if (depthBits < 0 || depthBits > 32) {
 277       return GL_FALSE;
 278    }
 279    if (stencilBits < 0 || stencilBits > STENCIL_BITS) {
 280       return GL_FALSE;
 281    }
 282    assert(accumRedBits >= 0);
 283    assert(accumGreenBits >= 0);
 284    assert(accumBlueBits >= 0);
 285    assert(accumAlphaBits >= 0);
 286
 287    vis->rgbMode          = rgbFlag;
 288    vis->doubleBufferMode = dbFlag;
 289    vis->stereoMode       = stereoFlag;
 290
 291    vis->redBits          = redBits;
 292    vis->greenBits        = greenBits;
 293    vis->blueBits         = blueBits;
 294    vis->alphaBits        = alphaBits;
 295    vis->rgbBits          = redBits + greenBits + blueBits;
 296
 297    vis->indexBits      = indexBits;
 298    vis->depthBits      = depthBits;
 299    vis->stencilBits    = stencilBits;
 300
 301    vis->accumRedBits   = accumRedBits;
 302    vis->accumGreenBits = accumGreenBits;
 303    vis->accumBlueBits  = accumBlueBits;
 304    vis->accumAlphaBits = accumAlphaBits;
 305
 306    vis->haveAccumBuffer   = accumRedBits > 0;
 307    vis->haveDepthBuffer   = depthBits > 0;
 308    vis->haveStencilBuffer = stencilBits > 0;
 309
 310    vis->numAuxBuffers = 0;
 311    vis->level = 0;
 312    vis->pixmapMode = 0;
 313    vis->sampleBuffers = numSamples > 0 ? 1 : 0;
 314    vis->samples = numSamples;
 315
 316    return GL_TRUE;
 317 }
 318
 319
 320 /**
 321  * Destroy a visual and free its memory.
 322  *
 323  * \param vis visual.
 324  *
 325  * Frees the visual structure.
 326  */
 327 void
 328 _mesa_destroy_visual( GLvisual *vis )
 329 {
 330    _mesa_free(vis);
 331 }
 332
 333 /*@}*/
 334
 335
 336 /**********************************************************************/
 337 /** \name Context allocation, initialization, destroying
 338  *
 339  * The purpose of the most initialization functions here is to provide the
 340  * default state values according to the OpenGL specification.
 341  */
 342 /**********************************************************************/
 343 /*@{*/
 344
 345
 346 /**
 347  * This is lame.  gdb only seems to recognize enum types that are
 348  * actually used somewhere.  We want to be able to print/use enum
 349  * values such as TEXTURE_2D_INDEX in gdb.  But we don't actually use
 350  * the gl_texture_index type anywhere.  Thus, this lame function.
 351  */
 352 static void
 353 dummy_enum_func(void)
 354 {
 355    gl_buffer_index bi;
 356    gl_colortable_index ci;
 357    gl_face_index fi;
 358    gl_frag_attrib fa;
 359    gl_frag_result fr;
 360    gl_texture_index ti;
 361    gl_vert_attrib va;
 362    gl_vert_result vr;
 363
 364    (void) bi;
 365    (void) ci;
 366    (void) fi;
 367    (void) fa;
 368    (void) fr;
 369    (void) ti;
 370    (void) va;
 371    (void) vr;
 372 }
 373
 374
 375 /**
 376  * One-time initialization mutex lock.
 377  *
 378  * \sa Used by one_time_init().
 379  */
 380 _glthread_DECLARE_STATIC_MUTEX(OneTimeLock);
 381
 382 /**
 383  * Calls all the various one-time-init functions in Mesa.
 384  *
 385  * While holding a global mutex lock, calls several initialization functions,
 386  * and sets the glapi callbacks if the \c MESA_DEBUG environment variable is
 387  * defined.
 388  *
 389  * \sa _math_init().
 390  */
 391 static void
 392 one_time_init( GLcontext *ctx )
 393 {
 394    static GLboolean alreadyCalled = GL_FALSE;
 395    (void) ctx;
 396    _glthread_LOCK_MUTEX(OneTimeLock);
 397    if (!alreadyCalled) {
 398       GLuint i;
 399
 400       /* do some implementation tests */
 401       assert( sizeof(GLbyte) == 1 );
 402       assert( sizeof(GLubyte) == 1 );
 403       assert( sizeof(GLshort) == 2 );
 404       assert( sizeof(GLushort) == 2 );
 405       assert( sizeof(GLint) == 4 );
 406       assert( sizeof(GLuint) == 4 );
 407
 408       _mesa_get_cpu_features();
 409
 410       _mesa_init_remap_table();
 411
 412       _mesa_init_sqrt_table();
 413
 414       for (i = 0; i < 256; i++) {
 415          _mesa_ubyte_to_float_color_tab[i] = (float) i / 255.0F;
 416       }
 417
 418       if (_mesa_getenv("MESA_DEBUG")) {
 419          _glapi_noop_enable_warnings(GL_TRUE);
 420          _glapi_set_warning_func( (_glapi_warning_func) _mesa_warning );
 421       }
 422       else {
 423          _glapi_noop_enable_warnings(GL_FALSE);
 424       }
 425
 426 #if defined(DEBUG) && defined(__DATE__) && defined(__TIME__)
 427       _mesa_debug(ctx, "Mesa %s DEBUG build %s %s\n",
 428                   MESA_VERSION_STRING, __DATE__, __TIME__);
 429 #endif
 430
 431       alreadyCalled = GL_TRUE;
 432    }
 433    _glthread_UNLOCK_MUTEX(OneTimeLock);
 434
 435    dummy_enum_func();
 436 }
 437
 438
 439 /**
 440  * Initialize fields of gl_current_attrib (aka ctx->Current.*)
 441  */
 442 static void
 443 _mesa_init_current(GLcontext *ctx)
 444 {
 445    GLuint i;
 446
 447    /* Init all to (0,0,0,1) */
 448    for (i = 0; i < Elements(ctx->Current.Attrib); i++) {
 449       ASSIGN_4V( ctx->Current.Attrib[i], 0.0, 0.0, 0.0, 1.0 );
 450    }
 451
 452    /* redo special cases: */
 453    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_WEIGHT], 1.0, 0.0, 0.0, 0.0 );
 454    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_NORMAL], 0.0, 0.0, 1.0, 1.0 );
 455    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR0], 1.0, 1.0, 1.0, 1.0 );
 456    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR1], 0.0, 0.0, 0.0, 1.0 );
 457    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR_INDEX], 1.0, 0.0, 0.0, 1.0 );
 458    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_EDGEFLAG], 1.0, 0.0, 0.0, 1.0 );
 459 }
 460
 461
 462 /**
 463  * Init vertex/fragment program limits.
 464  * Important: drivers should override these with actual limits.
 465  */
 466 static void
 467 init_program_limits(GLenum type, struct gl_program_constants *prog)
 468 {
 469    prog->MaxInstructions = MAX_PROGRAM_INSTRUCTIONS;
 470    prog->MaxAluInstructions = MAX_PROGRAM_INSTRUCTIONS;
 471    prog->MaxTexInstructions = MAX_PROGRAM_INSTRUCTIONS;
 472    prog->MaxTexIndirections = MAX_PROGRAM_INSTRUCTIONS;
 473    prog->MaxTemps = MAX_PROGRAM_TEMPS;
 474    prog->MaxEnvParams = MAX_PROGRAM_ENV_PARAMS;
 475    prog->MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
 476    prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 477
 478    if (type == GL_VERTEX_PROGRAM_ARB) {
 479       prog->MaxParameters = MAX_VERTEX_PROGRAM_PARAMS;
 480       prog->MaxAttribs = MAX_NV_VERTEX_PROGRAM_INPUTS;
 481       prog->MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 482    }
 483    else {
 484       prog->MaxParameters = MAX_NV_FRAGMENT_PROGRAM_PARAMS;
 485       prog->MaxAttribs = MAX_NV_FRAGMENT_PROGRAM_INPUTS;
 486       prog->MaxAddressRegs = MAX_FRAGMENT_PROGRAM_ADDRESS_REGS;
 487    }
 488
 489    /* Set the native limits to zero.  This implies that there is no native
 490     * support for shaders.  Let the drivers fill in the actual values.
 491     */
 492    prog->MaxNativeInstructions = 0;
 493    prog->MaxNativeAluInstructions = 0;
 494    prog->MaxNativeTexInstructions = 0;
 495    prog->MaxNativeTexIndirections = 0;
 496    prog->MaxNativeAttribs = 0;
 497    prog->MaxNativeTemps = 0;
 498    prog->MaxNativeAddressRegs = 0;
 499    prog->MaxNativeParameters = 0;
 500 }
 501
 502
 503 /**
 504  * Initialize fields of gl_constants (aka ctx->Const.*).
 505  * Use defaults from config.h.  The device drivers will often override
 506  * some of these values (such as number of texture units).
 507  */
 508 static void
 509 _mesa_init_constants(GLcontext *ctx)
 510 {
 511    assert(ctx);
 512
 513    assert(MAX_TEXTURE_LEVELS >= MAX_3D_TEXTURE_LEVELS);
 514    assert(MAX_TEXTURE_LEVELS >= MAX_CUBE_TEXTURE_LEVELS);
 515
 516    /* Max texture size should be <= max viewport size (render to texture) */
 517    assert((1 << (MAX_TEXTURE_LEVELS - 1)) <= MAX_WIDTH);
 518
 519    /* Constants, may be overriden (usually only reduced) by device drivers */
 520    ctx->Const.MaxTextureLevels = MAX_TEXTURE_LEVELS;
 521    ctx->Const.Max3DTextureLevels = MAX_3D_TEXTURE_LEVELS;
 522    ctx->Const.MaxCubeTextureLevels = MAX_CUBE_TEXTURE_LEVELS;
 523    ctx->Const.MaxTextureRectSize = MAX_TEXTURE_RECT_SIZE;
 524    ctx->Const.MaxArrayTextureLayers = MAX_ARRAY_TEXTURE_LAYERS;
 525    ctx->Const.MaxTextureCoordUnits = MAX_TEXTURE_COORD_UNITS;
 526    ctx->Const.MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 527    ctx->Const.MaxTextureUnits = MIN2(ctx->Const.MaxTextureCoordUnits,
 528                                      ctx->Const.MaxTextureImageUnits);
 529    ctx->Const.MaxTextureMaxAnisotropy = MAX_TEXTURE_MAX_ANISOTROPY;
 530    ctx->Const.MaxTextureLodBias = MAX_TEXTURE_LOD_BIAS;
 531    ctx->Const.MaxArrayLockSize = MAX_ARRAY_LOCK_SIZE;
 532    ctx->Const.SubPixelBits = SUB_PIXEL_BITS;
 533    ctx->Const.MinPointSize = MIN_POINT_SIZE;
 534    ctx->Const.MaxPointSize = MAX_POINT_SIZE;
 535    ctx->Const.MinPointSizeAA = MIN_POINT_SIZE;
 536    ctx->Const.MaxPointSizeAA = MAX_POINT_SIZE;
 537    ctx->Const.PointSizeGranularity = (GLfloat) POINT_SIZE_GRANULARITY;
 538    ctx->Const.MinLineWidth = MIN_LINE_WIDTH;
 539    ctx->Const.MaxLineWidth = MAX_LINE_WIDTH;
 540    ctx->Const.MinLineWidthAA = MIN_LINE_WIDTH;
 541    ctx->Const.MaxLineWidthAA = MAX_LINE_WIDTH;
 542    ctx->Const.LineWidthGranularity = (GLfloat) LINE_WIDTH_GRANULARITY;
 543    ctx->Const.MaxColorTableSize = MAX_COLOR_TABLE_SIZE;
 544    ctx->Const.MaxConvolutionWidth = MAX_CONVOLUTION_WIDTH;
 545    ctx->Const.MaxConvolutionHeight = MAX_CONVOLUTION_HEIGHT;
 546    ctx->Const.MaxClipPlanes = MAX_CLIP_PLANES;
 547    ctx->Const.MaxLights = MAX_LIGHTS;
 548    ctx->Const.MaxShininess = 128.0;
 549    ctx->Const.MaxSpotExponent = 128.0;
 550    ctx->Const.MaxViewportWidth = MAX_WIDTH;
 551    ctx->Const.MaxViewportHeight = MAX_HEIGHT;
 552 #if FEATURE_ARB_vertex_program
 553    init_program_limits(GL_VERTEX_PROGRAM_ARB, &ctx->Const.VertexProgram);
 554 #endif
 555 #if FEATURE_ARB_fragment_program
 556    init_program_limits(GL_FRAGMENT_PROGRAM_ARB, &ctx->Const.FragmentProgram);
 557 #endif
 558    ctx->Const.MaxProgramMatrices = MAX_PROGRAM_MATRICES;
 559    ctx->Const.MaxProgramMatrixStackDepth = MAX_PROGRAM_MATRIX_STACK_DEPTH;
 560
 561    /* CheckArrayBounds is overriden by drivers/x11 for X server */
 562    ctx->Const.CheckArrayBounds = GL_FALSE;
 563
 564    /* GL_ARB_draw_buffers */
 565    ctx->Const.MaxDrawBuffers = MAX_DRAW_BUFFERS;
 566
 567    /* GL_OES_read_format */
 568    ctx->Const.ColorReadFormat = GL_RGBA;
 569    ctx->Const.ColorReadType = GL_UNSIGNED_BYTE;
 570
 571 #if FEATURE_EXT_framebuffer_object
 572    ctx->Const.MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
 573    ctx->Const.MaxRenderbufferSize = MAX_WIDTH;
 574 #endif
 575
 576 #if FEATURE_ARB_vertex_shader
 577    ctx->Const.MaxVertexTextureImageUnits = MAX_VERTEX_TEXTURE_IMAGE_UNITS;
 578    ctx->Const.MaxVarying = MAX_VARYING;
 579 #endif
 580
 581    /* GL_ARB_framebuffer_object */
 582    ctx->Const.MaxSamples = 0;
 583
 584    /* GL_ARB_sync */
 585    ctx->Const.MaxServerWaitTimeout = (GLuint64) ~0;
 586
 587    /* GL_ATI_envmap_bumpmap */
 588    ctx->Const.SupportedBumpUnits = SUPPORTED_ATI_BUMP_UNITS;
 589
 590    /* GL_EXT_provoking_vertex */
 591    ctx->Const.QuadsFollowProvokingVertexConvention = GL_TRUE;
 592
 593    /* sanity checks */
 594    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
 595                                              ctx->Const.MaxTextureCoordUnits));
 596    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 597    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 598
 599    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 600    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 601    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
 602    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
 603
 604    /* check that we don't exceed the size of various bitfields */
 605    ASSERT(VERT_RESULT_MAX <=
 606           (8 * sizeof(ctx->VertexProgram._Current->Base.OutputsWritten)));
 607    ASSERT(FRAG_ATTRIB_MAX <=
 608           (8 * sizeof(ctx->FragmentProgram._Current->Base.InputsRead)));
 609 }
 610
 611
 612 /**
 613  * Do some sanity checks on the limits/constants for the given context.
 614  * Only called the first time a context is bound.
 615  */
 616 static void
 617 check_context_limits(GLcontext *ctx)
 618 {
 619    /* Many context limits/constants are limited by the size of
 620     * internal arrays.
 621     */
 622    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 623    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 624    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 625    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 626
 627    /* number of coord units cannot be greater than number of image units */
 628    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.MaxTextureImageUnits);
 629
 630    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 631    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 632    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 633    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 634
 635    /* make sure largest texture image is <= MAX_WIDTH in size */
 636    assert((1 << (ctx->Const.MaxTextureLevels - 1)) <= MAX_WIDTH);
 637    assert((1 << (ctx->Const.MaxCubeTextureLevels - 1)) <= MAX_WIDTH);
 638    assert((1 << (ctx->Const.Max3DTextureLevels - 1)) <= MAX_WIDTH);
 639
 640    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
 641    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
 642
 643    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 644
 645    /* XXX probably add more tests */
 646 }
 647
 648
 649 /**
 650  * Initialize the attribute groups in a GL context.
 651  *
 652  * \param ctx GL context.
 653  *
 654  * Initializes all the attributes, calling the respective <tt>init*</tt>
 655  * functions for the more complex data structures.
 656  */
 657 static GLboolean
 658 init_attrib_groups(GLcontext *ctx)
 659 {
 660    assert(ctx);
 661
 662    /* Constants */
 663    _mesa_init_constants( ctx );
 664
 665    /* Extensions */
 666    _mesa_init_extensions( ctx );
 667
 668    /* Attribute Groups */
 669    _mesa_init_accum( ctx );
 670    _mesa_init_attrib( ctx );
 671    _mesa_init_buffer_objects( ctx );
 672    _mesa_init_color( ctx );
 673    _mesa_init_colortables( ctx );
 674    _mesa_init_current( ctx );
 675    _mesa_init_depth( ctx );
 676    _mesa_init_debug( ctx );
 677    _mesa_init_display_list( ctx );
 678    _mesa_init_eval( ctx );
 679    _mesa_init_fbobjects( ctx );
 680    _mesa_init_feedback( ctx );
 681    _mesa_init_fog( ctx );
 682    _mesa_init_histogram( ctx );
 683    _mesa_init_hint( ctx );
 684    _mesa_init_line( ctx );
 685    _mesa_init_lighting( ctx );
 686    _mesa_init_matrix( ctx );
 687    _mesa_init_multisample( ctx );
 688    _mesa_init_pixel( ctx );
 689    _mesa_init_pixelstore( ctx );
 690    _mesa_init_point( ctx );
 691    _mesa_init_polygon( ctx );
 692    _mesa_init_program( ctx );
 693    _mesa_init_queryobj( ctx );
 694 #if FEATURE_ARB_sync
 695    _mesa_init_sync( ctx );
 696 #endif
 697    _mesa_init_rastpos( ctx );
 698    _mesa_init_scissor( ctx );
 699    _mesa_init_shader_state( ctx );
 700    _mesa_init_stencil( ctx );
 701    _mesa_init_transform( ctx );
 702    _mesa_init_varray( ctx );
 703    _mesa_init_viewport( ctx );
 704
 705    if (!_mesa_init_texture( ctx ))
 706       return GL_FALSE;
 707
 708    _mesa_init_texture_s3tc( ctx );
 709
 710    /* Miscellaneous */
 711    ctx->NewState = _NEW_ALL;
 712    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
 713    ctx->varying_vp_inputs = ~0;
 714
 715    return GL_TRUE;
 716 }
 717
 718
 719 /**
 720  * Update default objects in a GL context with respect to shared state.
 721  *
 722  * \param ctx GL context.
 723  *
 724  * Removes references to old default objects, (texture objects, program
 725  * objects, etc.) and changes to reference those from the current shared
 726  * state.
 727  */
 728 static GLboolean
 729 update_default_objects(GLcontext *ctx)
 730 {
 731    assert(ctx);
 732
 733    _mesa_update_default_objects_program(ctx);
 734    _mesa_update_default_objects_texture(ctx);
 735    _mesa_update_default_objects_buffer_objects(ctx);
 736
 737    return GL_TRUE;
 738 }
 739
 740
 741 /**
 742  * This is the default function we plug into all dispatch table slots
 743  * This helps prevents a segfault when someone calls a GL function without
 744  * first checking if the extension's supported.
 745  */
 746 static int
 747 generic_nop(void)
 748 {
 749    _mesa_warning(NULL, "User called no-op dispatch function (an unsupported extension function?)");
 750    return 0;
 751 }
 752
 753
 754 /**
 755  * Allocate and initialize a new dispatch table.
 756  */
 757 static struct _glapi_table *
 758 alloc_dispatch_table(void)
 759 {
 760    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
 761     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
 762     * Mesa we do this to accomodate different versions of libGL and various
 763     * DRI drivers.
 764     */
 765    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
 766                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
 767    struct _glapi_table *table =
 768       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
 769    if (table) {
 770       _glapi_proc *entry = (_glapi_proc *) table;
 771       GLint i;
 772       for (i = 0; i < numEntries; i++) {
 773          entry[i] = (_glapi_proc) generic_nop;
 774       }
 775    }
 776    return table;
 777 }
 778
 779
 780 /**
 781  * Initialize a GLcontext struct (rendering context).
 782  *
 783  * This includes allocating all the other structs and arrays which hang off of
 784  * the context by pointers.
 785  * Note that the driver needs to pass in its dd_function_table here since
 786  * we need to at least call driverFunctions->NewTextureObject to create the
 787  * default texture objects.
 788  *
 789  * Called by _mesa_create_context().
 790  *
 791  * Performs the imports and exports callback tables initialization, and
 792  * miscellaneous one-time initializations. If no shared context is supplied one
 793  * is allocated, and increase its reference count.  Setups the GL API dispatch
 794  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
 795  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
 796  * for debug flags.
 797  *
 798  * \param ctx the context to initialize
 799  * \param visual describes the visual attributes for this context
 800  * \param share_list points to context to share textures, display lists,
 801  *        etc with, or NULL
 802  * \param driverFunctions table of device driver functions for this context
 803  *        to use
 804  * \param driverContext pointer to driver-specific context data
 805  */
 806 GLboolean
 807 _mesa_initialize_context(GLcontext *ctx,
 808                          const GLvisual *visual,
 809                          GLcontext *share_list,
 810                          const struct dd_function_table *driverFunctions,
 811                          void *driverContext)
 812 {
 813    struct gl_shared_state *shared;
 814
 815    /*ASSERT(driverContext);*/
 816    assert(driverFunctions->NewTextureObject);
 817    assert(driverFunctions->FreeTexImageData);
 818
 819    /* misc one-time initializations */
 820    one_time_init(ctx);
 821
 822    ctx->Visual = *visual;
 823    ctx->DrawBuffer = NULL;
 824    ctx->ReadBuffer = NULL;
 825    ctx->WinSysDrawBuffer = NULL;
 826    ctx->WinSysReadBuffer = NULL;
 827
 828    /* Plug in driver functions and context pointer here.
 829     * This is important because when we call alloc_shared_state() below
 830     * we'll call ctx->Driver.NewTextureObject() to create the default
 831     * textures.
 832     */
 833    ctx->Driver = *driverFunctions;
 834    ctx->DriverCtx = driverContext;
 835
 836    if (share_list) {
 837       /* share state with another context */
 838       shared = share_list->Shared;
 839    }
 840    else {
 841       /* allocate new, unshared state */
 842       shared = _mesa_alloc_shared_state(ctx);
 843       if (!shared)
 844          return GL_FALSE;
 845    }
 846
 847    _glthread_LOCK_MUTEX(shared->Mutex);
 848    ctx->Shared = shared;
 849    shared->RefCount++;
 850    _glthread_UNLOCK_MUTEX(shared->Mutex);
 851
 852    if (!init_attrib_groups( ctx )) {
 853       _mesa_free_shared_state(ctx, ctx->Shared);
 854       return GL_FALSE;
 855    }
 856
 857    /* setup the API dispatch tables */
 858    ctx->Exec = alloc_dispatch_table();
 859    ctx->Save = alloc_dispatch_table();
 860    if (!ctx->Exec || !ctx->Save) {
 861       _mesa_free_shared_state(ctx, ctx->Shared);
 862       if (ctx->Exec)
 863          _mesa_free(ctx->Exec);
 864       return GL_FALSE;
 865    }
 866 #if FEATURE_dispatch
 867    _mesa_init_exec_table(ctx->Exec);
 868 #endif
 869    ctx->CurrentDispatch = ctx->Exec;
 870
 871 #if FEATURE_dlist
 872    _mesa_init_save_table(ctx->Save);
 873    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
 874 #endif
 875
 876    /* Neutral tnl module stuff */
 877    _mesa_init_exec_vtxfmt( ctx );
 878    ctx->TnlModule.Current = NULL;
 879    ctx->TnlModule.SwapCount = 0;
 880
 881    ctx->FragmentProgram._MaintainTexEnvProgram
 882       = (_mesa_getenv("MESA_TEX_PROG") != NULL);
 883
 884    ctx->VertexProgram._MaintainTnlProgram
 885       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
 886    if (ctx->VertexProgram._MaintainTnlProgram) {
 887       /* this is required... */
 888       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
 889    }
 890
 891 #ifdef FEATURE_extra_context_init
 892    _mesa_initialize_context_extra(ctx);
 893 #endif
 894
 895    ctx->FirstTimeCurrent = GL_TRUE;
 896
 897    return GL_TRUE;
 898 }
 899
 900
 901 /**
 902  * Allocate and initialize a GLcontext structure.
 903  * Note that the driver needs to pass in its dd_function_table here since
 904  * we need to at least call driverFunctions->NewTextureObject to initialize
 905  * the rendering context.
 906  *
 907  * \param visual a GLvisual pointer (we copy the struct contents)
 908  * \param share_list another context to share display lists with or NULL
 909  * \param driverFunctions points to the dd_function_table into which the
 910  *        driver has plugged in all its special functions.
 911  * \param driverContext points to the device driver's private context state
 912  *
 913  * \return pointer to a new __GLcontextRec or NULL if error.
 914  */
 915 GLcontext *
 916 _mesa_create_context(const GLvisual *visual,
 917                      GLcontext *share_list,
 918                      const struct dd_function_table *driverFunctions,
 919                      void *driverContext)
 920 {
 921    GLcontext *ctx;
 922
 923    ASSERT(visual);
 924    /*ASSERT(driverContext);*/
 925
 926    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
 927    if (!ctx)
 928       return NULL;
 929
 930    if (_mesa_initialize_context(ctx, visual, share_list,
 931                                 driverFunctions, driverContext)) {
 932       return ctx;
 933    }
 934    else {
 935       _mesa_free(ctx);
 936       return NULL;
 937    }
 938 }
 939
 940
 941 /**
 942  * Free the data associated with the given context.
 943  *
 944  * But doesn't free the GLcontext struct itself.
 945  *
 946  * \sa _mesa_initialize_context() and init_attrib_groups().
 947  */
 948 void
 949 _mesa_free_context_data( GLcontext *ctx )
 950 {
 951    GLint RefCount;
 952
 953    if (!_mesa_get_current_context()){
 954       /* No current context, but we may need one in order to delete
 955        * texture objs, etc.  So temporarily bind the context now.
 956        */
 957       _mesa_make_current(ctx, NULL, NULL);
 958    }
 959
 960    /* unreference WinSysDraw/Read buffers */
 961    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
 962    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
 963    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
 964    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
 965
 966    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
 967    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 968    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
 969
 970    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
 971    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 972    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
 973
 974    _mesa_free_attrib_data(ctx);
 975    _mesa_free_lighting_data( ctx );
 976    _mesa_free_eval_data( ctx );
 977    _mesa_free_texture_data( ctx );
 978    _mesa_free_matrix_data( ctx );
 979    _mesa_free_viewport_data( ctx );
 980    _mesa_free_colortables_data( ctx );
 981    _mesa_free_program_data(ctx);
 982    _mesa_free_shader_state(ctx);
 983    _mesa_free_queryobj_data(ctx);
 984 #if FEATURE_ARB_sync
 985    _mesa_free_sync_data(ctx);
 986 #endif
 987    _mesa_free_varray_data(ctx);
 988
 989    _mesa_delete_array_object(ctx, ctx->Array.DefaultArrayObj);
 990
 991 #if FEATURE_ARB_pixel_buffer_object
 992    _mesa_reference_buffer_object(ctx, &ctx->Pack.BufferObj, NULL);
 993    _mesa_reference_buffer_object(ctx, &ctx->Unpack.BufferObj, NULL);
 994 #endif
 995
 996 #if FEATURE_ARB_vertex_buffer_object
 997    _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj, NULL);
 998    _mesa_reference_buffer_object(ctx, &ctx->Array.ElementArrayBufferObj, NULL);
 999 #endif
1000
1001    /* free dispatch tables */
1002    _mesa_free(ctx->Exec);
1003    _mesa_free(ctx->Save);
1004
1005    /* Shared context state (display lists, textures, etc) */
1006    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1007    RefCount = --ctx->Shared->RefCount;
1008    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1009    assert(RefCount >= 0);
1010    if (RefCount == 0) {
1011       /* free shared state */
1012       _mesa_free_shared_state( ctx, ctx->Shared );
1013    }
1014
1015    /* needs to be after freeing shared state */
1016    _mesa_free_display_list_data(ctx);
1017
1018    if (ctx->Extensions.String)
1019       _mesa_free((void *) ctx->Extensions.String);
1020
1021    /* unbind the context if it's currently bound */
1022    if (ctx == _mesa_get_current_context()) {
1023       _mesa_make_current(NULL, NULL, NULL);
1024    }
1025 }
1026
1027
1028 /**
1029  * Destroy a GLcontext structure.
1030  *
1031  * \param ctx GL context.
1032  *
1033  * Calls _mesa_free_context_data() and frees the GLcontext structure itself.
1034  */
1035 void
1036 _mesa_destroy_context( GLcontext *ctx )
1037 {
1038    if (ctx) {
1039       _mesa_free_context_data(ctx);
1040       _mesa_free( (void *) ctx );
1041    }
1042 }
1043
1044
1045 #if _HAVE_FULL_GL
1046 /**
1047  * Copy attribute groups from one context to another.
1048  *
1049  * \param src source context
1050  * \param dst destination context
1051  * \param mask bitwise OR of GL_*_BIT flags
1052  *
1053  * According to the bits specified in \p mask, copies the corresponding
1054  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1055  * memcpy is not enough due to the existence of internal pointers in their data
1056  * structures.
1057  */
1058 void
1059 _mesa_copy_context( const GLcontext *src, GLcontext *dst, GLuint mask )
1060 {
1061    if (mask & GL_ACCUM_BUFFER_BIT) {
1062       /* OK to memcpy */
1063       dst->Accum = src->Accum;
1064    }
1065    if (mask & GL_COLOR_BUFFER_BIT) {
1066       /* OK to memcpy */
1067       dst->Color = src->Color;
1068    }
1069    if (mask & GL_CURRENT_BIT) {
1070       /* OK to memcpy */
1071       dst->Current = src->Current;
1072    }
1073    if (mask & GL_DEPTH_BUFFER_BIT) {
1074       /* OK to memcpy */
1075       dst->Depth = src->Depth;
1076    }
1077    if (mask & GL_ENABLE_BIT) {
1078       /* no op */
1079    }
1080    if (mask & GL_EVAL_BIT) {
1081       /* OK to memcpy */
1082       dst->Eval = src->Eval;
1083    }
1084    if (mask & GL_FOG_BIT) {
1085       /* OK to memcpy */
1086       dst->Fog = src->Fog;
1087    }
1088    if (mask & GL_HINT_BIT) {
1089       /* OK to memcpy */
1090       dst->Hint = src->Hint;
1091    }
1092    if (mask & GL_LIGHTING_BIT) {
1093       GLuint i;
1094       /* begin with memcpy */
1095       dst->Light = src->Light;
1096       /* fixup linked lists to prevent pointer insanity */
1097       make_empty_list( &(dst->Light.EnabledList) );
1098       for (i = 0; i < MAX_LIGHTS; i++) {
1099          if (dst->Light.Light[i].Enabled) {
1100             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1101          }
1102       }
1103    }
1104    if (mask & GL_LINE_BIT) {
1105       /* OK to memcpy */
1106       dst->Line = src->Line;
1107    }
1108    if (mask & GL_LIST_BIT) {
1109       /* OK to memcpy */
1110       dst->List = src->List;
1111    }
1112    if (mask & GL_PIXEL_MODE_BIT) {
1113       /* OK to memcpy */
1114       dst->Pixel = src->Pixel;
1115    }
1116    if (mask & GL_POINT_BIT) {
1117       /* OK to memcpy */
1118       dst->Point = src->Point;
1119    }
1120    if (mask & GL_POLYGON_BIT) {
1121       /* OK to memcpy */
1122       dst->Polygon = src->Polygon;
1123    }
1124    if (mask & GL_POLYGON_STIPPLE_BIT) {
1125       /* Use loop instead of MEMCPY due to problem with Portland Group's
1126        * C compiler.  Reported by John Stone.
1127        */
1128       GLuint i;
1129       for (i = 0; i < 32; i++) {
1130          dst->PolygonStipple[i] = src->PolygonStipple[i];
1131       }
1132    }
1133    if (mask & GL_SCISSOR_BIT) {
1134       /* OK to memcpy */
1135       dst->Scissor = src->Scissor;
1136    }
1137    if (mask & GL_STENCIL_BUFFER_BIT) {
1138       /* OK to memcpy */
1139       dst->Stencil = src->Stencil;
1140    }
1141    if (mask & GL_TEXTURE_BIT) {
1142       /* Cannot memcpy because of pointers */
1143       _mesa_copy_texture_state(src, dst);
1144    }
1145    if (mask & GL_TRANSFORM_BIT) {
1146       /* OK to memcpy */
1147       dst->Transform = src->Transform;
1148    }
1149    if (mask & GL_VIEWPORT_BIT) {
1150       /* Cannot use memcpy, because of pointers in GLmatrix _WindowMap */
1151       dst->Viewport.X = src->Viewport.X;
1152       dst->Viewport.Y = src->Viewport.Y;
1153       dst->Viewport.Width = src->Viewport.Width;
1154       dst->Viewport.Height = src->Viewport.Height;
1155       dst->Viewport.Near = src->Viewport.Near;
1156       dst->Viewport.Far = src->Viewport.Far;
1157       _math_matrix_copy(&dst->Viewport._WindowMap, &src->Viewport._WindowMap);
1158    }
1159
1160    /* XXX FIXME:  Call callbacks?
1161     */
1162    dst->NewState = _NEW_ALL;
1163 }
1164 #endif
1165
1166
1167 /**
1168  * Check if the given context can render into the given framebuffer
1169  * by checking visual attributes.
1170  *
1171  * Most of these tests could go away because Mesa is now pretty flexible
1172  * in terms of mixing rendering contexts with framebuffers.  As long
1173  * as RGB vs. CI mode agree, we're probably good.
1174  *
1175  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1176  */
1177 static GLboolean
1178 check_compatible(const GLcontext *ctx, const GLframebuffer *buffer)
1179 {
1180    const GLvisual *ctxvis = &ctx->Visual;
1181    const GLvisual *bufvis = &buffer->Visual;
1182
1183    if (ctxvis == bufvis)
1184       return GL_TRUE;
1185
1186    if (ctxvis->rgbMode != bufvis->rgbMode)
1187       return GL_FALSE;
1188 #if 0
1189    /* disabling this fixes the fgl_glxgears pbuffer demo */
1190    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1191       return GL_FALSE;
1192 #endif
1193    if (ctxvis->stereoMode && !bufvis->stereoMode)
1194       return GL_FALSE;
1195    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1196       return GL_FALSE;
1197    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1198       return GL_FALSE;
1199    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1200       return GL_FALSE;
1201    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1202       return GL_FALSE;
1203    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1204       return GL_FALSE;
1205    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1206       return GL_FALSE;
1207 #if 0
1208    /* disabled (see bug 11161) */
1209    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1210       return GL_FALSE;
1211 #endif
1212    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1213       return GL_FALSE;
1214
1215    return GL_TRUE;
1216 }
1217
1218
1219 /**
1220  * Do one-time initialization for the given framebuffer.  Specifically,
1221  * ask the driver for the window's current size and update the framebuffer
1222  * object to match.
1223  * Really, the device driver should totally take care of this.
1224  */
1225 static void
1226 initialize_framebuffer_size(GLcontext *ctx, GLframebuffer *fb)
1227 {
1228    GLuint width, height;
1229    if (ctx->Driver.GetBufferSize) {
1230       ctx->Driver.GetBufferSize(fb, &width, &height);
1231       if (ctx->Driver.ResizeBuffers)
1232          ctx->Driver.ResizeBuffers(ctx, fb, width, height);
1233       fb->Initialized = GL_TRUE;
1234    }
1235 }
1236
1237
1238 /**
1239  * Check if the viewport/scissor size has not yet been initialized.
1240  * Initialize the size if the given width and height are non-zero.
1241  */
1242 void
1243 _mesa_check_init_viewport(GLcontext *ctx, GLuint width, GLuint height)
1244 {
1245    if (!ctx->ViewportInitialized && width > 0 && height > 0) {
1246       /* Note: set flag here, before calling _mesa_set_viewport(), to prevent
1247        * potential infinite recursion.
1248        */
1249       ctx->ViewportInitialized = GL_TRUE;
1250       _mesa_set_viewport(ctx, 0, 0, width, height);
1251       _mesa_set_scissor(ctx, 0, 0, width, height);
1252    }
1253 }
1254
1255
1256 /**
1257  * Bind the given context to the given drawBuffer and readBuffer and
1258  * make it the current context for the calling thread.
1259  * We'll render into the drawBuffer and read pixels from the
1260  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1261  *
1262  * We check that the context's and framebuffer's visuals are compatible
1263  * and return immediately if they're not.
1264  *
1265  * \param newCtx  the new GL context. If NULL then there will be no current GL
1266  *                context.
1267  * \param drawBuffer  the drawing framebuffer
1268  * \param readBuffer  the reading framebuffer
1269  */
1270 GLboolean
1271 _mesa_make_current( GLcontext *newCtx, GLframebuffer *drawBuffer,
1272                     GLframebuffer *readBuffer )
1273 {
1274    if (MESA_VERBOSE & VERBOSE_API)
1275       _mesa_debug(newCtx, "_mesa_make_current()\n");
1276
1277    /* Check that the context's and framebuffer's visuals are compatible.
1278     */
1279    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1280       if (!check_compatible(newCtx, drawBuffer)) {
1281          _mesa_warning(newCtx,
1282               "MakeCurrent: incompatible visuals for context and drawbuffer");
1283          return GL_FALSE;
1284       }
1285    }
1286    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1287       if (!check_compatible(newCtx, readBuffer)) {
1288          _mesa_warning(newCtx,
1289               "MakeCurrent: incompatible visuals for context and readbuffer");
1290          return GL_FALSE;
1291       }
1292    }
1293
1294    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1295    _glapi_set_context((void *) newCtx);
1296    ASSERT(_mesa_get_current_context() == newCtx);
1297
1298    if (!newCtx) {
1299       _glapi_set_dispatch(NULL);  /* none current */
1300    }
1301    else {
1302       _glapi_set_dispatch(newCtx->CurrentDispatch);
1303
1304       if (drawBuffer && readBuffer) {
1305          /* TODO: check if newCtx and buffer's visual match??? */
1306
1307          ASSERT(drawBuffer->Name == 0);
1308          ASSERT(readBuffer->Name == 0);
1309          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1310          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1311
1312          /*
1313           * Only set the context's Draw/ReadBuffer fields if they're NULL
1314           * or not bound to a user-created FBO.
1315           */
1316          if (!newCtx->DrawBuffer || newCtx->DrawBuffer->Name == 0) {
1317             /* KW: merge conflict here, revisit.
1318              */
1319             /* fix up the fb fields - these will end up wrong otherwise
1320              * if the DRIdrawable changes, and everything relies on them.
1321              * This is a bit messy (same as needed in _mesa_BindFramebufferEXT)
1322              */
1323             unsigned int i;
1324             GLenum buffers[MAX_DRAW_BUFFERS];
1325
1326             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1327
1328             for(i = 0; i < newCtx->Const.MaxDrawBuffers; i++) {
1329                buffers[i] = newCtx->Color.DrawBuffer[i];
1330             }
1331
1332             _mesa_drawbuffers(newCtx, newCtx->Const.MaxDrawBuffers, buffers, NULL);
1333          }
1334          if (!newCtx->ReadBuffer || newCtx->ReadBuffer->Name == 0) {
1335             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1336          }
1337
1338          /* XXX only set this flag if we're really changing the draw/read
1339           * framebuffer bindings.
1340           */
1341          newCtx->NewState |= _NEW_BUFFERS;
1342
1343 #if 1
1344          /* We want to get rid of these lines: */
1345
1346 #if _HAVE_FULL_GL
1347          if (!drawBuffer->Initialized) {
1348             initialize_framebuffer_size(newCtx, drawBuffer);
1349          }
1350          if (readBuffer != drawBuffer && !readBuffer->Initialized) {
1351             initialize_framebuffer_size(newCtx, readBuffer);
1352          }
1353
1354          _mesa_resizebuffers(newCtx);
1355 #endif
1356
1357 #else
1358          /* We want the drawBuffer and readBuffer to be initialized by
1359           * the driver.
1360           * This generally means the Width and Height match the actual
1361           * window size and the renderbuffers (both hardware and software
1362           * based) are allocated to match.  The later can generally be
1363           * done with a call to _mesa_resize_framebuffer().
1364           *
1365           * It's theoretically possible for a buffer to have zero width
1366           * or height, but for now, assert check that the driver did what's
1367           * expected of it.
1368           */
1369          ASSERT(drawBuffer->Width > 0);
1370          ASSERT(drawBuffer->Height > 0);
1371 #endif
1372
1373          if (drawBuffer) {
1374             _mesa_check_init_viewport(newCtx,
1375                                       drawBuffer->Width, drawBuffer->Height);
1376          }
1377       }
1378
1379       if (newCtx->FirstTimeCurrent) {
1380          check_context_limits(newCtx);
1381
1382          /* We can use this to help debug user's problems.  Tell them to set
1383           * the MESA_INFO env variable before running their app.  Then the
1384           * first time each context is made current we'll print some useful
1385           * information.
1386           */
1387          if (_mesa_getenv("MESA_INFO")) {
1388             _mesa_print_info();
1389          }
1390
1391          newCtx->FirstTimeCurrent = GL_FALSE;
1392       }
1393    }
1394
1395    return GL_TRUE;
1396 }
1397
1398
1399 /**
1400  * Make context 'ctx' share the display lists, textures and programs
1401  * that are associated with 'ctxToShare'.
1402  * Any display lists, textures or programs associated with 'ctx' will
1403  * be deleted if nobody else is sharing them.
1404  */
1405 GLboolean
1406 _mesa_share_state(GLcontext *ctx, GLcontext *ctxToShare)
1407 {
1408    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1409       struct gl_shared_state *oldSharedState = ctx->Shared;
1410       GLint RefCount;
1411
1412       ctx->Shared = ctxToShare->Shared;
1413
1414       _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1415       ctx->Shared->RefCount++;
1416       _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1417
1418       update_default_objects(ctx);
1419
1420       _glthread_LOCK_MUTEX(oldSharedState->Mutex);
1421       RefCount = --oldSharedState->RefCount;
1422       _glthread_UNLOCK_MUTEX(oldSharedState->Mutex);
1423
1424       if (RefCount == 0) {
1425          _mesa_free_shared_state(ctx, oldSharedState);
1426       }
1427
1428       return GL_TRUE;
1429    }
1430    else {
1431       return GL_FALSE;
1432    }
1433 }
1434
1435
1436
1437 /**
1438  * \return pointer to the current GL context for this thread.
1439  *
1440  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1441  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1442  * context.h.
1443  */
1444 GLcontext *
1445 _mesa_get_current_context( void )
1446 {
1447    return (GLcontext *) _glapi_get_context();
1448 }
1449
1450
1451 /**
1452  * Get context's current API dispatch table.
1453  *
1454  * It'll either be the immediate-mode execute dispatcher or the display list
1455  * compile dispatcher.
1456  *
1457  * \param ctx GL context.
1458  *
1459  * \return pointer to dispatch_table.
1460  *
1461  * Simply returns __GLcontextRec::CurrentDispatch.
1462  */
1463 struct _glapi_table *
1464 _mesa_get_dispatch(GLcontext *ctx)
1465 {
1466    return ctx->CurrentDispatch;
1467 }
1468
1469 /*@}*/
1470
1471
1472 /**********************************************************************/
1473 /** \name Miscellaneous functions                                     */
1474 /**********************************************************************/
1475 /*@{*/
1476
1477 /**
1478  * Record an error.
1479  *
1480  * \param ctx GL context.
1481  * \param error error code.
1482  *
1483  * Records the given error code and call the driver's dd_function_table::Error
1484  * function if defined.
1485  *
1486  * \sa
1487  * This is called via _mesa_error().
1488  */
1489 void
1490 _mesa_record_error(GLcontext *ctx, GLenum error)
1491 {
1492    if (!ctx)
1493       return;
1494
1495    if (ctx->ErrorValue == GL_NO_ERROR) {
1496       ctx->ErrorValue = error;
1497    }
1498
1499    /* Call device driver's error handler, if any.  This is used on the Mac. */
1500    if (ctx->Driver.Error) {
1501       ctx->Driver.Error(ctx);
1502    }
1503 }
1504
1505
1506 /**
1507  * Flush commands and wait for completion.
1508  */
1509 void
1510 _mesa_finish(GLcontext *ctx)
1511 {
1512    FLUSH_CURRENT( ctx, 0 );
1513    if (ctx->Driver.Finish) {
1514       ctx->Driver.Finish(ctx);
1515    }
1516 }
1517
1518
1519 /**
1520  * Flush commands.
1521  */
1522 void
1523 _mesa_flush(GLcontext *ctx)
1524 {
1525    FLUSH_CURRENT( ctx, 0 );
1526    if (ctx->Driver.Flush) {
1527       ctx->Driver.Flush(ctx);
1528    }
1529 }
1530
1531
1532
1533 /**
1534  * Execute glFinish().
1535  *
1536  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1537  * dd_function_table::Finish driver callback, if not NULL.
1538  */
1539 void GLAPIENTRY
1540 _mesa_Finish(void)
1541 {
1542    GET_CURRENT_CONTEXT(ctx);
1543    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1544    _mesa_finish(ctx);
1545 }
1546
1547
1548 /**
1549  * Execute glFlush().
1550  *
1551  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1552  * dd_function_table::Flush driver callback, if not NULL.
1553  */
1554 void GLAPIENTRY
1555 _mesa_Flush(void)
1556 {
1557    GET_CURRENT_CONTEXT(ctx);
1558    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1559    _mesa_flush(ctx);
1560 }
1561
1562
1563 /**
1564  * Set mvp_with_dp4 flag.  If a driver has a preference for DP4 over
1565  * MUL/MAD, or vice versa, call this function to register that.
1566  * Otherwise we default to MUL/MAD.
1567  */
1568 void
1569 _mesa_set_mvp_with_dp4( GLcontext *ctx,
1570                         GLboolean flag )
1571 {
1572    ctx->mvp_with_dp4 = flag;
1573 }
1574
1575
1576
1577 /**
1578  * Prior to drawing anything with glBegin, glDrawArrays, etc. this function
1579  * is called to see if it's valid to render.  This involves checking that
1580  * the current shader is valid and the framebuffer is complete.
1581  * If an error is detected it'll be recorded here.
1582  * \return GL_TRUE if OK to render, GL_FALSE if not
1583  */
1584 GLboolean
1585 _mesa_valid_to_render(GLcontext *ctx, const char *where)
1586 {
1587    if (ctx->Shader.CurrentProgram) {
1588       /* using shaders */
1589       if (!ctx->Shader.CurrentProgram->LinkStatus) {
1590          _mesa_error(ctx, GL_INVALID_OPERATION,
1591                      "%s(shader not linked), where");
1592          return GL_FALSE;
1593       }
1594 #if 0 /* not normally enabled */
1595       {
1596          char errMsg[100];
1597          if (!_mesa_validate_shader_program(ctx, ctx->Shader.CurrentProgram,
1598                                             errMsg)) {
1599             _mesa_warning(ctx, "Shader program %u is invalid: %s",
1600                           ctx->Shader.CurrentProgram->Name, errMsg);
1601          }
1602       }
1603 #endif
1604    }
1605    else {
1606       if (ctx->VertexProgram.Enabled && !ctx->VertexProgram._Enabled) {
1607          _mesa_error(ctx, GL_INVALID_OPERATION,
1608                      "%s(vertex program not valid)", where);
1609          return GL_FALSE;
1610       }
1611       if (ctx->FragmentProgram.Enabled && !ctx->FragmentProgram._Enabled) {
1612          _mesa_error(ctx, GL_INVALID_OPERATION,
1613                      "%s(fragment program not valid)", where);
1614          return GL_FALSE;
1615       }
1616    }
1617
1618    if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
1619       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
1620                   "%s(incomplete framebuffer)", where);
1621       return GL_FALSE;
1622    }
1623
1624 #ifdef DEBUG
1625    if (ctx->Shader.Flags & GLSL_LOG) {
1626       struct gl_shader_program *shProg = ctx->Shader.CurrentProgram;
1627       if (shProg) {
1628          if (!shProg->_Used) {
1629             /* This is the first time this shader is being used.
1630              * Append shader's constants/uniforms to log file.
1631              */
1632             GLuint i;
1633             for (i = 0; i < shProg->NumShaders; i++) {
1634                struct gl_shader *sh = shProg->Shaders[i];
1635                if (sh->Type == GL_VERTEX_SHADER) {
1636                   _mesa_append_uniforms_to_file(sh,
1637                                                 &shProg->VertexProgram->Base);
1638                }
1639                else if (sh->Type == GL_FRAGMENT_SHADER) {
1640                   _mesa_append_uniforms_to_file(sh,
1641                                                 &shProg->FragmentProgram->Base);
1642                }
1643             }
1644             shProg->_Used = GL_TRUE;
1645          }
1646       }
1647    }
1648 #endif
1649
1650    return GL_TRUE;
1651 }
1652
1653
1654 /*@}*/