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