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 #if FEATURE_EXT_framebuffer_object
 568    ctx->Const.MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
 569    ctx->Const.MaxRenderbufferSize = MAX_WIDTH;
 570 #endif
 571
 572 #if FEATURE_ARB_vertex_shader
 573    ctx->Const.MaxVertexTextureImageUnits = MAX_VERTEX_TEXTURE_IMAGE_UNITS;
 574    ctx->Const.MaxVarying = MAX_VARYING;
 575 #endif
 576
 577    /* GL_ARB_framebuffer_object */
 578    ctx->Const.MaxSamples = 0;
 579
 580    /* GL_ARB_sync */
 581    ctx->Const.MaxServerWaitTimeout = (GLuint64) ~0;
 582
 583    /* GL_ATI_envmap_bumpmap */
 584    ctx->Const.SupportedBumpUnits = SUPPORTED_ATI_BUMP_UNITS;
 585
 586    /* GL_EXT_provoking_vertex */
 587    ctx->Const.QuadsFollowProvokingVertexConvention = GL_TRUE;
 588
 589    /* sanity checks */
 590    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
 591                                              ctx->Const.MaxTextureCoordUnits));
 592    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 593    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 594
 595    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 596    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 597    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
 598    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
 599
 600    /* check that we don't exceed the size of various bitfields */
 601    ASSERT(VERT_RESULT_MAX <=
 602           (8 * sizeof(ctx->VertexProgram._Current->Base.OutputsWritten)));
 603    ASSERT(FRAG_ATTRIB_MAX <=
 604           (8 * sizeof(ctx->FragmentProgram._Current->Base.InputsRead)));
 605 }
 606
 607
 608 /**
 609  * Do some sanity checks on the limits/constants for the given context.
 610  * Only called the first time a context is bound.
 611  */
 612 static void
 613 check_context_limits(GLcontext *ctx)
 614 {
 615    /* Many context limits/constants are limited by the size of
 616     * internal arrays.
 617     */
 618    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 619    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 620    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 621    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 622
 623    /* number of coord units cannot be greater than number of image units */
 624    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.MaxTextureImageUnits);
 625
 626    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 627    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 628    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 629    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 630
 631    /* make sure largest texture image is <= MAX_WIDTH in size */
 632    assert((1 << (ctx->Const.MaxTextureLevels - 1)) <= MAX_WIDTH);
 633    assert((1 << (ctx->Const.MaxCubeTextureLevels - 1)) <= MAX_WIDTH);
 634    assert((1 << (ctx->Const.Max3DTextureLevels - 1)) <= MAX_WIDTH);
 635
 636    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
 637    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
 638
 639    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 640
 641    /* XXX probably add more tests */
 642 }
 643
 644
 645 /**
 646  * Initialize the attribute groups in a GL context.
 647  *
 648  * \param ctx GL context.
 649  *
 650  * Initializes all the attributes, calling the respective <tt>init*</tt>
 651  * functions for the more complex data structures.
 652  */
 653 static GLboolean
 654 init_attrib_groups(GLcontext *ctx)
 655 {
 656    assert(ctx);
 657
 658    /* Constants */
 659    _mesa_init_constants( ctx );
 660
 661    /* Extensions */
 662    _mesa_init_extensions( ctx );
 663
 664    /* Attribute Groups */
 665    _mesa_init_accum( ctx );
 666    _mesa_init_attrib( ctx );
 667    _mesa_init_buffer_objects( ctx );
 668    _mesa_init_color( ctx );
 669    _mesa_init_colortables( ctx );
 670    _mesa_init_current( ctx );
 671    _mesa_init_depth( ctx );
 672    _mesa_init_debug( ctx );
 673    _mesa_init_display_list( ctx );
 674    _mesa_init_eval( ctx );
 675    _mesa_init_fbobjects( ctx );
 676    _mesa_init_feedback( ctx );
 677    _mesa_init_fog( ctx );
 678    _mesa_init_histogram( ctx );
 679    _mesa_init_hint( ctx );
 680    _mesa_init_line( ctx );
 681    _mesa_init_lighting( ctx );
 682    _mesa_init_matrix( ctx );
 683    _mesa_init_multisample( ctx );
 684    _mesa_init_pixel( ctx );
 685    _mesa_init_pixelstore( ctx );
 686    _mesa_init_point( ctx );
 687    _mesa_init_polygon( ctx );
 688    _mesa_init_program( ctx );
 689    _mesa_init_queryobj( ctx );
 690 #if FEATURE_ARB_sync
 691    _mesa_init_sync( ctx );
 692 #endif
 693    _mesa_init_rastpos( ctx );
 694    _mesa_init_scissor( ctx );
 695    _mesa_init_shader_state( ctx );
 696    _mesa_init_stencil( ctx );
 697    _mesa_init_transform( ctx );
 698    _mesa_init_varray( ctx );
 699    _mesa_init_viewport( ctx );
 700
 701    if (!_mesa_init_texture( ctx ))
 702       return GL_FALSE;
 703
 704    _mesa_init_texture_s3tc( ctx );
 705
 706    /* Miscellaneous */
 707    ctx->NewState = _NEW_ALL;
 708    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
 709    ctx->varying_vp_inputs = ~0;
 710
 711    return GL_TRUE;
 712 }
 713
 714
 715 /**
 716  * Update default objects in a GL context with respect to shared state.
 717  *
 718  * \param ctx GL context.
 719  *
 720  * Removes references to old default objects, (texture objects, program
 721  * objects, etc.) and changes to reference those from the current shared
 722  * state.
 723  */
 724 static GLboolean
 725 update_default_objects(GLcontext *ctx)
 726 {
 727    assert(ctx);
 728
 729    _mesa_update_default_objects_program(ctx);
 730    _mesa_update_default_objects_texture(ctx);
 731    _mesa_update_default_objects_buffer_objects(ctx);
 732
 733    return GL_TRUE;
 734 }
 735
 736
 737 /**
 738  * This is the default function we plug into all dispatch table slots
 739  * This helps prevents a segfault when someone calls a GL function without
 740  * first checking if the extension's supported.
 741  */
 742 static int
 743 generic_nop(void)
 744 {
 745    _mesa_warning(NULL, "User called no-op dispatch function (an unsupported extension function?)");
 746    return 0;
 747 }
 748
 749
 750 /**
 751  * Allocate and initialize a new dispatch table.
 752  */
 753 static struct _glapi_table *
 754 alloc_dispatch_table(void)
 755 {
 756    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
 757     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
 758     * Mesa we do this to accomodate different versions of libGL and various
 759     * DRI drivers.
 760     */
 761    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
 762                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
 763    struct _glapi_table *table =
 764       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
 765    if (table) {
 766       _glapi_proc *entry = (_glapi_proc *) table;
 767       GLint i;
 768       for (i = 0; i < numEntries; i++) {
 769          entry[i] = (_glapi_proc) generic_nop;
 770       }
 771    }
 772    return table;
 773 }
 774
 775
 776 /**
 777  * Initialize a GLcontext struct (rendering context).
 778  *
 779  * This includes allocating all the other structs and arrays which hang off of
 780  * the context by pointers.
 781  * Note that the driver needs to pass in its dd_function_table here since
 782  * we need to at least call driverFunctions->NewTextureObject to create the
 783  * default texture objects.
 784  *
 785  * Called by _mesa_create_context().
 786  *
 787  * Performs the imports and exports callback tables initialization, and
 788  * miscellaneous one-time initializations. If no shared context is supplied one
 789  * is allocated, and increase its reference count.  Setups the GL API dispatch
 790  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
 791  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
 792  * for debug flags.
 793  *
 794  * \param ctx the context to initialize
 795  * \param visual describes the visual attributes for this context
 796  * \param share_list points to context to share textures, display lists,
 797  *        etc with, or NULL
 798  * \param driverFunctions table of device driver functions for this context
 799  *        to use
 800  * \param driverContext pointer to driver-specific context data
 801  */
 802 GLboolean
 803 _mesa_initialize_context(GLcontext *ctx,
 804                          const GLvisual *visual,
 805                          GLcontext *share_list,
 806                          const struct dd_function_table *driverFunctions,
 807                          void *driverContext)
 808 {
 809    struct gl_shared_state *shared;
 810
 811    /*ASSERT(driverContext);*/
 812    assert(driverFunctions->NewTextureObject);
 813    assert(driverFunctions->FreeTexImageData);
 814
 815    /* misc one-time initializations */
 816    one_time_init(ctx);
 817
 818    ctx->Visual = *visual;
 819    ctx->DrawBuffer = NULL;
 820    ctx->ReadBuffer = NULL;
 821    ctx->WinSysDrawBuffer = NULL;
 822    ctx->WinSysReadBuffer = NULL;
 823
 824    /* Plug in driver functions and context pointer here.
 825     * This is important because when we call alloc_shared_state() below
 826     * we'll call ctx->Driver.NewTextureObject() to create the default
 827     * textures.
 828     */
 829    ctx->Driver = *driverFunctions;
 830    ctx->DriverCtx = driverContext;
 831
 832    if (share_list) {
 833       /* share state with another context */
 834       shared = share_list->Shared;
 835    }
 836    else {
 837       /* allocate new, unshared state */
 838       shared = _mesa_alloc_shared_state(ctx);
 839       if (!shared)
 840          return GL_FALSE;
 841    }
 842
 843    _glthread_LOCK_MUTEX(shared->Mutex);
 844    ctx->Shared = shared;
 845    shared->RefCount++;
 846    _glthread_UNLOCK_MUTEX(shared->Mutex);
 847
 848    if (!init_attrib_groups( ctx )) {
 849       _mesa_free_shared_state(ctx, ctx->Shared);
 850       return GL_FALSE;
 851    }
 852
 853    /* setup the API dispatch tables */
 854    ctx->Exec = alloc_dispatch_table();
 855    ctx->Save = alloc_dispatch_table();
 856    if (!ctx->Exec || !ctx->Save) {
 857       _mesa_free_shared_state(ctx, ctx->Shared);
 858       if (ctx->Exec)
 859          _mesa_free(ctx->Exec);
 860       return GL_FALSE;
 861    }
 862 #if FEATURE_dispatch
 863    _mesa_init_exec_table(ctx->Exec);
 864 #endif
 865    ctx->CurrentDispatch = ctx->Exec;
 866
 867 #if FEATURE_dlist
 868    _mesa_init_save_table(ctx->Save);
 869    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
 870 #endif
 871
 872    /* Neutral tnl module stuff */
 873    _mesa_init_exec_vtxfmt( ctx );
 874    ctx->TnlModule.Current = NULL;
 875    ctx->TnlModule.SwapCount = 0;
 876
 877    ctx->FragmentProgram._MaintainTexEnvProgram
 878       = (_mesa_getenv("MESA_TEX_PROG") != NULL);
 879
 880    ctx->VertexProgram._MaintainTnlProgram
 881       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
 882    if (ctx->VertexProgram._MaintainTnlProgram) {
 883       /* this is required... */
 884       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
 885    }
 886
 887 #ifdef FEATURE_extra_context_init
 888    _mesa_initialize_context_extra(ctx);
 889 #endif
 890
 891    ctx->FirstTimeCurrent = GL_TRUE;
 892
 893    return GL_TRUE;
 894 }
 895
 896
 897 /**
 898  * Allocate and initialize a GLcontext structure.
 899  * Note that the driver needs to pass in its dd_function_table here since
 900  * we need to at least call driverFunctions->NewTextureObject to initialize
 901  * the rendering context.
 902  *
 903  * \param visual a GLvisual pointer (we copy the struct contents)
 904  * \param share_list another context to share display lists with or NULL
 905  * \param driverFunctions points to the dd_function_table into which the
 906  *        driver has plugged in all its special functions.
 907  * \param driverContext points to the device driver's private context state
 908  *
 909  * \return pointer to a new __GLcontextRec or NULL if error.
 910  */
 911 GLcontext *
 912 _mesa_create_context(const GLvisual *visual,
 913                      GLcontext *share_list,
 914                      const struct dd_function_table *driverFunctions,
 915                      void *driverContext)
 916 {
 917    GLcontext *ctx;
 918
 919    ASSERT(visual);
 920    /*ASSERT(driverContext);*/
 921
 922    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
 923    if (!ctx)
 924       return NULL;
 925
 926    if (_mesa_initialize_context(ctx, visual, share_list,
 927                                 driverFunctions, driverContext)) {
 928       return ctx;
 929    }
 930    else {
 931       _mesa_free(ctx);
 932       return NULL;
 933    }
 934 }
 935
 936
 937 /**
 938  * Free the data associated with the given context.
 939  *
 940  * But doesn't free the GLcontext struct itself.
 941  *
 942  * \sa _mesa_initialize_context() and init_attrib_groups().
 943  */
 944 void
 945 _mesa_free_context_data( GLcontext *ctx )
 946 {
 947    GLint RefCount;
 948
 949    if (!_mesa_get_current_context()){
 950       /* No current context, but we may need one in order to delete
 951        * texture objs, etc.  So temporarily bind the context now.
 952        */
 953       _mesa_make_current(ctx, NULL, NULL);
 954    }
 955
 956    /* unreference WinSysDraw/Read buffers */
 957    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
 958    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
 959    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
 960    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
 961
 962    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
 963    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 964    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
 965
 966    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
 967    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 968    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
 969
 970    _mesa_free_attrib_data(ctx);
 971    _mesa_free_lighting_data( ctx );
 972    _mesa_free_eval_data( ctx );
 973    _mesa_free_texture_data( ctx );
 974    _mesa_free_matrix_data( ctx );
 975    _mesa_free_viewport_data( ctx );
 976    _mesa_free_colortables_data( ctx );
 977    _mesa_free_program_data(ctx);
 978    _mesa_free_shader_state(ctx);
 979    _mesa_free_queryobj_data(ctx);
 980 #if FEATURE_ARB_sync
 981    _mesa_free_sync_data(ctx);
 982 #endif
 983    _mesa_free_varray_data(ctx);
 984
 985    _mesa_delete_array_object(ctx, ctx->Array.DefaultArrayObj);
 986
 987 #if FEATURE_ARB_pixel_buffer_object
 988    _mesa_reference_buffer_object(ctx, &ctx->Pack.BufferObj, NULL);
 989    _mesa_reference_buffer_object(ctx, &ctx->Unpack.BufferObj, NULL);
 990 #endif
 991
 992 #if FEATURE_ARB_vertex_buffer_object
 993    _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj, NULL);
 994    _mesa_reference_buffer_object(ctx, &ctx->Array.ElementArrayBufferObj, NULL);
 995 #endif
 996
 997    /* free dispatch tables */
 998    _mesa_free(ctx->Exec);
 999    _mesa_free(ctx->Save);
1000
1001    /* Shared context state (display lists, textures, etc) */
1002    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1003    RefCount = --ctx->Shared->RefCount;
1004    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1005    assert(RefCount >= 0);
1006    if (RefCount == 0) {
1007       /* free shared state */
1008       _mesa_free_shared_state( ctx, ctx->Shared );
1009    }
1010
1011    /* needs to be after freeing shared state */
1012    _mesa_free_display_list_data(ctx);
1013
1014    if (ctx->Extensions.String)
1015       _mesa_free((void *) ctx->Extensions.String);
1016
1017    /* unbind the context if it's currently bound */
1018    if (ctx == _mesa_get_current_context()) {
1019       _mesa_make_current(NULL, NULL, NULL);
1020    }
1021 }
1022
1023
1024 /**
1025  * Destroy a GLcontext structure.
1026  *
1027  * \param ctx GL context.
1028  *
1029  * Calls _mesa_free_context_data() and frees the GLcontext structure itself.
1030  */
1031 void
1032 _mesa_destroy_context( GLcontext *ctx )
1033 {
1034    if (ctx) {
1035       _mesa_free_context_data(ctx);
1036       _mesa_free( (void *) ctx );
1037    }
1038 }
1039
1040
1041 #if _HAVE_FULL_GL
1042 /**
1043  * Copy attribute groups from one context to another.
1044  *
1045  * \param src source context
1046  * \param dst destination context
1047  * \param mask bitwise OR of GL_*_BIT flags
1048  *
1049  * According to the bits specified in \p mask, copies the corresponding
1050  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1051  * memcpy is not enough due to the existence of internal pointers in their data
1052  * structures.
1053  */
1054 void
1055 _mesa_copy_context( const GLcontext *src, GLcontext *dst, GLuint mask )
1056 {
1057    if (mask & GL_ACCUM_BUFFER_BIT) {
1058       /* OK to memcpy */
1059       dst->Accum = src->Accum;
1060    }
1061    if (mask & GL_COLOR_BUFFER_BIT) {
1062       /* OK to memcpy */
1063       dst->Color = src->Color;
1064    }
1065    if (mask & GL_CURRENT_BIT) {
1066       /* OK to memcpy */
1067       dst->Current = src->Current;
1068    }
1069    if (mask & GL_DEPTH_BUFFER_BIT) {
1070       /* OK to memcpy */
1071       dst->Depth = src->Depth;
1072    }
1073    if (mask & GL_ENABLE_BIT) {
1074       /* no op */
1075    }
1076    if (mask & GL_EVAL_BIT) {
1077       /* OK to memcpy */
1078       dst->Eval = src->Eval;
1079    }
1080    if (mask & GL_FOG_BIT) {
1081       /* OK to memcpy */
1082       dst->Fog = src->Fog;
1083    }
1084    if (mask & GL_HINT_BIT) {
1085       /* OK to memcpy */
1086       dst->Hint = src->Hint;
1087    }
1088    if (mask & GL_LIGHTING_BIT) {
1089       GLuint i;
1090       /* begin with memcpy */
1091       dst->Light = src->Light;
1092       /* fixup linked lists to prevent pointer insanity */
1093       make_empty_list( &(dst->Light.EnabledList) );
1094       for (i = 0; i < MAX_LIGHTS; i++) {
1095          if (dst->Light.Light[i].Enabled) {
1096             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1097          }
1098       }
1099    }
1100    if (mask & GL_LINE_BIT) {
1101       /* OK to memcpy */
1102       dst->Line = src->Line;
1103    }
1104    if (mask & GL_LIST_BIT) {
1105       /* OK to memcpy */
1106       dst->List = src->List;
1107    }
1108    if (mask & GL_PIXEL_MODE_BIT) {
1109       /* OK to memcpy */
1110       dst->Pixel = src->Pixel;
1111    }
1112    if (mask & GL_POINT_BIT) {
1113       /* OK to memcpy */
1114       dst->Point = src->Point;
1115    }
1116    if (mask & GL_POLYGON_BIT) {
1117       /* OK to memcpy */
1118       dst->Polygon = src->Polygon;
1119    }
1120    if (mask & GL_POLYGON_STIPPLE_BIT) {
1121       /* Use loop instead of MEMCPY due to problem with Portland Group's
1122        * C compiler.  Reported by John Stone.
1123        */
1124       GLuint i;
1125       for (i = 0; i < 32; i++) {
1126          dst->PolygonStipple[i] = src->PolygonStipple[i];
1127       }
1128    }
1129    if (mask & GL_SCISSOR_BIT) {
1130       /* OK to memcpy */
1131       dst->Scissor = src->Scissor;
1132    }
1133    if (mask & GL_STENCIL_BUFFER_BIT) {
1134       /* OK to memcpy */
1135       dst->Stencil = src->Stencil;
1136    }
1137    if (mask & GL_TEXTURE_BIT) {
1138       /* Cannot memcpy because of pointers */
1139       _mesa_copy_texture_state(src, dst);
1140    }
1141    if (mask & GL_TRANSFORM_BIT) {
1142       /* OK to memcpy */
1143       dst->Transform = src->Transform;
1144    }
1145    if (mask & GL_VIEWPORT_BIT) {
1146       /* Cannot use memcpy, because of pointers in GLmatrix _WindowMap */
1147       dst->Viewport.X = src->Viewport.X;
1148       dst->Viewport.Y = src->Viewport.Y;
1149       dst->Viewport.Width = src->Viewport.Width;
1150       dst->Viewport.Height = src->Viewport.Height;
1151       dst->Viewport.Near = src->Viewport.Near;
1152       dst->Viewport.Far = src->Viewport.Far;
1153       _math_matrix_copy(&dst->Viewport._WindowMap, &src->Viewport._WindowMap);
1154    }
1155
1156    /* XXX FIXME:  Call callbacks?
1157     */
1158    dst->NewState = _NEW_ALL;
1159 }
1160 #endif
1161
1162
1163 /**
1164  * Check if the given context can render into the given framebuffer
1165  * by checking visual attributes.
1166  *
1167  * Most of these tests could go away because Mesa is now pretty flexible
1168  * in terms of mixing rendering contexts with framebuffers.  As long
1169  * as RGB vs. CI mode agree, we're probably good.
1170  *
1171  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1172  */
1173 static GLboolean
1174 check_compatible(const GLcontext *ctx, const GLframebuffer *buffer)
1175 {
1176    const GLvisual *ctxvis = &ctx->Visual;
1177    const GLvisual *bufvis = &buffer->Visual;
1178
1179    if (ctxvis == bufvis)
1180       return GL_TRUE;
1181
1182    if (ctxvis->rgbMode != bufvis->rgbMode)
1183       return GL_FALSE;
1184 #if 0
1185    /* disabling this fixes the fgl_glxgears pbuffer demo */
1186    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1187       return GL_FALSE;
1188 #endif
1189    if (ctxvis->stereoMode && !bufvis->stereoMode)
1190       return GL_FALSE;
1191    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1192       return GL_FALSE;
1193    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1194       return GL_FALSE;
1195    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1196       return GL_FALSE;
1197    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1198       return GL_FALSE;
1199    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1200       return GL_FALSE;
1201    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1202       return GL_FALSE;
1203 #if 0
1204    /* disabled (see bug 11161) */
1205    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1206       return GL_FALSE;
1207 #endif
1208    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1209       return GL_FALSE;
1210
1211    return GL_TRUE;
1212 }
1213
1214
1215 /**
1216  * Do one-time initialization for the given framebuffer.  Specifically,
1217  * ask the driver for the window's current size and update the framebuffer
1218  * object to match.
1219  * Really, the device driver should totally take care of this.
1220  */
1221 static void
1222 initialize_framebuffer_size(GLcontext *ctx, GLframebuffer *fb)
1223 {
1224    GLuint width, height;
1225    if (ctx->Driver.GetBufferSize) {
1226       ctx->Driver.GetBufferSize(fb, &width, &height);
1227       if (ctx->Driver.ResizeBuffers)
1228          ctx->Driver.ResizeBuffers(ctx, fb, width, height);
1229       fb->Initialized = GL_TRUE;
1230    }
1231 }
1232
1233
1234 /**
1235  * Check if the viewport/scissor size has not yet been initialized.
1236  * Initialize the size if the given width and height are non-zero.
1237  */
1238 void
1239 _mesa_check_init_viewport(GLcontext *ctx, GLuint width, GLuint height)
1240 {
1241    if (!ctx->ViewportInitialized && width > 0 && height > 0) {
1242       /* Note: set flag here, before calling _mesa_set_viewport(), to prevent
1243        * potential infinite recursion.
1244        */
1245       ctx->ViewportInitialized = GL_TRUE;
1246       _mesa_set_viewport(ctx, 0, 0, width, height);
1247       _mesa_set_scissor(ctx, 0, 0, width, height);
1248    }
1249 }
1250
1251
1252 /**
1253  * Bind the given context to the given drawBuffer and readBuffer and
1254  * make it the current context for the calling thread.
1255  * We'll render into the drawBuffer and read pixels from the
1256  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1257  *
1258  * We check that the context's and framebuffer's visuals are compatible
1259  * and return immediately if they're not.
1260  *
1261  * \param newCtx  the new GL context. If NULL then there will be no current GL
1262  *                context.
1263  * \param drawBuffer  the drawing framebuffer
1264  * \param readBuffer  the reading framebuffer
1265  */
1266 GLboolean
1267 _mesa_make_current( GLcontext *newCtx, GLframebuffer *drawBuffer,
1268                     GLframebuffer *readBuffer )
1269 {
1270    if (MESA_VERBOSE & VERBOSE_API)
1271       _mesa_debug(newCtx, "_mesa_make_current()\n");
1272
1273    /* Check that the context's and framebuffer's visuals are compatible.
1274     */
1275    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1276       if (!check_compatible(newCtx, drawBuffer)) {
1277          _mesa_warning(newCtx,
1278               "MakeCurrent: incompatible visuals for context and drawbuffer");
1279          return GL_FALSE;
1280       }
1281    }
1282    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1283       if (!check_compatible(newCtx, readBuffer)) {
1284          _mesa_warning(newCtx,
1285               "MakeCurrent: incompatible visuals for context and readbuffer");
1286          return GL_FALSE;
1287       }
1288    }
1289
1290    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1291    _glapi_set_context((void *) newCtx);
1292    ASSERT(_mesa_get_current_context() == newCtx);
1293
1294    if (!newCtx) {
1295       _glapi_set_dispatch(NULL);  /* none current */
1296    }
1297    else {
1298       _glapi_set_dispatch(newCtx->CurrentDispatch);
1299
1300       if (drawBuffer && readBuffer) {
1301          /* TODO: check if newCtx and buffer's visual match??? */
1302
1303          ASSERT(drawBuffer->Name == 0);
1304          ASSERT(readBuffer->Name == 0);
1305          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1306          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1307
1308          /*
1309           * Only set the context's Draw/ReadBuffer fields if they're NULL
1310           * or not bound to a user-created FBO.
1311           */
1312          if (!newCtx->DrawBuffer || newCtx->DrawBuffer->Name == 0) {
1313             /* KW: merge conflict here, revisit.
1314              */
1315             /* fix up the fb fields - these will end up wrong otherwise
1316              * if the DRIdrawable changes, and everything relies on them.
1317              * This is a bit messy (same as needed in _mesa_BindFramebufferEXT)
1318              */
1319             unsigned int i;
1320             GLenum buffers[MAX_DRAW_BUFFERS];
1321
1322             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1323
1324             for(i = 0; i < newCtx->Const.MaxDrawBuffers; i++) {
1325                buffers[i] = newCtx->Color.DrawBuffer[i];
1326             }
1327
1328             _mesa_drawbuffers(newCtx, newCtx->Const.MaxDrawBuffers, buffers, NULL);
1329          }
1330          if (!newCtx->ReadBuffer || newCtx->ReadBuffer->Name == 0) {
1331             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1332          }
1333
1334          /* XXX only set this flag if we're really changing the draw/read
1335           * framebuffer bindings.
1336           */
1337          newCtx->NewState |= _NEW_BUFFERS;
1338
1339 #if 1
1340          /* We want to get rid of these lines: */
1341
1342 #if _HAVE_FULL_GL
1343          if (!drawBuffer->Initialized) {
1344             initialize_framebuffer_size(newCtx, drawBuffer);
1345          }
1346          if (readBuffer != drawBuffer && !readBuffer->Initialized) {
1347             initialize_framebuffer_size(newCtx, readBuffer);
1348          }
1349
1350          _mesa_resizebuffers(newCtx);
1351 #endif
1352
1353 #else
1354          /* We want the drawBuffer and readBuffer to be initialized by
1355           * the driver.
1356           * This generally means the Width and Height match the actual
1357           * window size and the renderbuffers (both hardware and software
1358           * based) are allocated to match.  The later can generally be
1359           * done with a call to _mesa_resize_framebuffer().
1360           *
1361           * It's theoretically possible for a buffer to have zero width
1362           * or height, but for now, assert check that the driver did what's
1363           * expected of it.
1364           */
1365          ASSERT(drawBuffer->Width > 0);
1366          ASSERT(drawBuffer->Height > 0);
1367 #endif
1368
1369          if (drawBuffer) {
1370             _mesa_check_init_viewport(newCtx,
1371                                       drawBuffer->Width, drawBuffer->Height);
1372          }
1373       }
1374
1375       if (newCtx->FirstTimeCurrent) {
1376          check_context_limits(newCtx);
1377
1378          /* We can use this to help debug user's problems.  Tell them to set
1379           * the MESA_INFO env variable before running their app.  Then the
1380           * first time each context is made current we'll print some useful
1381           * information.
1382           */
1383          if (_mesa_getenv("MESA_INFO")) {
1384             _mesa_print_info();
1385          }
1386
1387          newCtx->FirstTimeCurrent = GL_FALSE;
1388       }
1389    }
1390
1391    return GL_TRUE;
1392 }
1393
1394
1395 /**
1396  * Make context 'ctx' share the display lists, textures and programs
1397  * that are associated with 'ctxToShare'.
1398  * Any display lists, textures or programs associated with 'ctx' will
1399  * be deleted if nobody else is sharing them.
1400  */
1401 GLboolean
1402 _mesa_share_state(GLcontext *ctx, GLcontext *ctxToShare)
1403 {
1404    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1405       struct gl_shared_state *oldSharedState = ctx->Shared;
1406       GLint RefCount;
1407
1408       ctx->Shared = ctxToShare->Shared;
1409
1410       _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1411       ctx->Shared->RefCount++;
1412       _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1413
1414       update_default_objects(ctx);
1415
1416       _glthread_LOCK_MUTEX(oldSharedState->Mutex);
1417       RefCount = --oldSharedState->RefCount;
1418       _glthread_UNLOCK_MUTEX(oldSharedState->Mutex);
1419
1420       if (RefCount == 0) {
1421          _mesa_free_shared_state(ctx, oldSharedState);
1422       }
1423
1424       return GL_TRUE;
1425    }
1426    else {
1427       return GL_FALSE;
1428    }
1429 }
1430
1431
1432
1433 /**
1434  * \return pointer to the current GL context for this thread.
1435  *
1436  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1437  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1438  * context.h.
1439  */
1440 GLcontext *
1441 _mesa_get_current_context( void )
1442 {
1443    return (GLcontext *) _glapi_get_context();
1444 }
1445
1446
1447 /**
1448  * Get context's current API dispatch table.
1449  *
1450  * It'll either be the immediate-mode execute dispatcher or the display list
1451  * compile dispatcher.
1452  *
1453  * \param ctx GL context.
1454  *
1455  * \return pointer to dispatch_table.
1456  *
1457  * Simply returns __GLcontextRec::CurrentDispatch.
1458  */
1459 struct _glapi_table *
1460 _mesa_get_dispatch(GLcontext *ctx)
1461 {
1462    return ctx->CurrentDispatch;
1463 }
1464
1465 /*@}*/
1466
1467
1468 /**********************************************************************/
1469 /** \name Miscellaneous functions                                     */
1470 /**********************************************************************/
1471 /*@{*/
1472
1473 /**
1474  * Record an error.
1475  *
1476  * \param ctx GL context.
1477  * \param error error code.
1478  *
1479  * Records the given error code and call the driver's dd_function_table::Error
1480  * function if defined.
1481  *
1482  * \sa
1483  * This is called via _mesa_error().
1484  */
1485 void
1486 _mesa_record_error(GLcontext *ctx, GLenum error)
1487 {
1488    if (!ctx)
1489       return;
1490
1491    if (ctx->ErrorValue == GL_NO_ERROR) {
1492       ctx->ErrorValue = error;
1493    }
1494
1495    /* Call device driver's error handler, if any.  This is used on the Mac. */
1496    if (ctx->Driver.Error) {
1497       ctx->Driver.Error(ctx);
1498    }
1499 }
1500
1501
1502 /**
1503  * Flush commands and wait for completion.
1504  */
1505 void
1506 _mesa_finish(GLcontext *ctx)
1507 {
1508    FLUSH_CURRENT( ctx, 0 );
1509    if (ctx->Driver.Finish) {
1510       ctx->Driver.Finish(ctx);
1511    }
1512 }
1513
1514
1515 /**
1516  * Flush commands.
1517  */
1518 void
1519 _mesa_flush(GLcontext *ctx)
1520 {
1521    FLUSH_CURRENT( ctx, 0 );
1522    if (ctx->Driver.Flush) {
1523       ctx->Driver.Flush(ctx);
1524    }
1525 }
1526
1527
1528
1529 /**
1530  * Execute glFinish().
1531  *
1532  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1533  * dd_function_table::Finish driver callback, if not NULL.
1534  */
1535 void GLAPIENTRY
1536 _mesa_Finish(void)
1537 {
1538    GET_CURRENT_CONTEXT(ctx);
1539    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1540    _mesa_finish(ctx);
1541 }
1542
1543
1544 /**
1545  * Execute glFlush().
1546  *
1547  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1548  * dd_function_table::Flush driver callback, if not NULL.
1549  */
1550 void GLAPIENTRY
1551 _mesa_Flush(void)
1552 {
1553    GET_CURRENT_CONTEXT(ctx);
1554    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1555    _mesa_flush(ctx);
1556 }
1557
1558
1559 /**
1560  * Set mvp_with_dp4 flag.  If a driver has a preference for DP4 over
1561  * MUL/MAD, or vice versa, call this function to register that.
1562  * Otherwise we default to MUL/MAD.
1563  */
1564 void
1565 _mesa_set_mvp_with_dp4( GLcontext *ctx,
1566                         GLboolean flag )
1567 {
1568    ctx->mvp_with_dp4 = flag;
1569 }
1570
1571
1572
1573 /**
1574  * Prior to drawing anything with glBegin, glDrawArrays, etc. this function
1575  * is called to see if it's valid to render.  This involves checking that
1576  * the current shader is valid and the framebuffer is complete.
1577  * If an error is detected it'll be recorded here.
1578  * \return GL_TRUE if OK to render, GL_FALSE if not
1579  */
1580 GLboolean
1581 _mesa_valid_to_render(GLcontext *ctx, const char *where)
1582 {
1583    if (ctx->Shader.CurrentProgram) {
1584       /* using shaders */
1585       if (!ctx->Shader.CurrentProgram->LinkStatus) {
1586          _mesa_error(ctx, GL_INVALID_OPERATION,
1587                      "%s(shader not linked), where");
1588          return GL_FALSE;
1589       }
1590 #if 0 /* not normally enabled */
1591       {
1592          char errMsg[100];
1593          if (!_mesa_validate_shader_program(ctx, ctx->Shader.CurrentProgram,
1594                                             errMsg)) {
1595             _mesa_warning(ctx, "Shader program %u is invalid: %s",
1596                           ctx->Shader.CurrentProgram->Name, errMsg);
1597          }
1598       }
1599 #endif
1600    }
1601    else {
1602       if (ctx->VertexProgram.Enabled && !ctx->VertexProgram._Enabled) {
1603          _mesa_error(ctx, GL_INVALID_OPERATION,
1604                      "%s(vertex program not valid)", where);
1605          return GL_FALSE;
1606       }
1607       if (ctx->FragmentProgram.Enabled && !ctx->FragmentProgram._Enabled) {
1608          _mesa_error(ctx, GL_INVALID_OPERATION,
1609                      "%s(fragment program not valid)", where);
1610          return GL_FALSE;
1611       }
1612    }
1613
1614    if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
1615       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
1616                   "%s(incomplete framebuffer)", where);
1617       return GL_FALSE;
1618    }
1619
1620 #ifdef DEBUG
1621    if (ctx->Shader.Flags & GLSL_LOG) {
1622       struct gl_shader_program *shProg = ctx->Shader.CurrentProgram;
1623       if (shProg) {
1624          if (!shProg->_Used) {
1625             /* This is the first time this shader is being used.
1626              * Append shader's constants/uniforms to log file.
1627              */
1628             GLuint i;
1629             for (i = 0; i < shProg->NumShaders; i++) {
1630                struct gl_shader *sh = shProg->Shaders[i];
1631                if (sh->Type == GL_VERTEX_SHADER) {
1632                   _mesa_append_uniforms_to_file(sh,
1633                                                 &shProg->VertexProgram->Base);
1634                }
1635                else if (sh->Type == GL_FRAGMENT_SHADER) {
1636                   _mesa_append_uniforms_to_file(sh,
1637                                                 &shProg->FragmentProgram->Base);
1638                }
1639             }
1640             shProg->_Used = GL_TRUE;
1641          }
1642       }
1643    }
1644 #endif
1645
1646    return GL_TRUE;
1647 }
1648
1649
1650 /*@}*/