src/mesa/main/context.c

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   5  * Copyright (C) 2008  VMware, Inc.  All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * 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 "imports.h"
  81 #include "accum.h"
  82 #include "api_exec.h"
  83 #include "api_loopback.h"
  84 #include "arrayobj.h"
  85 #include "attrib.h"
  86 #include "blend.h"
  87 #include "buffers.h"
  88 #include "bufferobj.h"
  89 #include "context.h"
  90 #include "cpuinfo.h"
  91 #include "debug.h"
  92 #include "debug_output.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 "formats.h"
 101 #include "framebuffer.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 "performance_monitor.h"
 110 #include "pipelineobj.h"
 111 #include "pixel.h"
 112 #include "pixelstore.h"
 113 #include "points.h"
 114 #include "polygon.h"
 115 #include "queryobj.h"
 116 #include "syncobj.h"
 117 #include "rastpos.h"
 118 #include "remap.h"
 119 #include "scissor.h"
 120 #include "shared.h"
 121 #include "shaderobj.h"
 122 #include "shaderimage.h"
 123 #include "util/simple_list.h"
 124 #include "util/strtod.h"
 125 #include "state.h"
 126 #include "stencil.h"
 127 #include "texcompress_s3tc.h"
 128 #include "texstate.h"
 129 #include "transformfeedback.h"
 130 #include "mtypes.h"
 131 #include "varray.h"
 132 #include "version.h"
 133 #include "viewport.h"
 134 #include "vtxfmt.h"
 135 #include "program/program.h"
 136 #include "program/prog_print.h"
 137 #include "math/m_matrix.h"
 138 #include "main/dispatch.h" /* for _gloffset_COUNT */
 139 #include "uniforms.h"
 140 #include "macros.h"
 141
 142 #ifdef USE_SPARC_ASM
 143 #include "sparc/sparc.h"
 144 #endif
 145
 146 #include "compiler/glsl/glsl_parser_extras.h"
 147 #include <stdbool.h>
 148
 149
 150 #ifndef MESA_VERBOSE
 151 int MESA_VERBOSE = 0;
 152 #endif
 153
 154 #ifndef MESA_DEBUG_FLAGS
 155 int MESA_DEBUG_FLAGS = 0;
 156 #endif
 157
 158
 159 /* ubyte -> float conversion */
 160 GLfloat _mesa_ubyte_to_float_color_tab[256];
 161
 162
 163
 164 /**
 165  * Swap buffers notification callback.
 166  *
 167  * \param ctx GL context.
 168  *
 169  * Called by window system just before swapping buffers.
 170  * We have to finish any pending rendering.
 171  */
 172 void
 173 _mesa_notifySwapBuffers(struct gl_context *ctx)
 174 {
 175    if (MESA_VERBOSE & VERBOSE_SWAPBUFFERS)
 176       _mesa_debug(ctx, "SwapBuffers\n");
 177    FLUSH_CURRENT( ctx, 0 );
 178    if (ctx->Driver.Flush) {
 179       ctx->Driver.Flush(ctx);
 180    }
 181 }
 182
 183
 184 /**********************************************************************/
 185 /** \name GL Visual allocation/destruction                            */
 186 /**********************************************************************/
 187 /*@{*/
 188
 189 /**
 190  * Allocates a struct gl_config structure and initializes it via
 191  * _mesa_initialize_visual().
 192  *
 193  * \param dbFlag double buffering
 194  * \param stereoFlag stereo buffer
 195  * \param depthBits requested bits per depth buffer value. Any value in [0, 32]
 196  * is acceptable but the actual depth type will be GLushort or GLuint as
 197  * needed.
 198  * \param stencilBits requested minimum bits per stencil buffer value
 199  * \param accumRedBits, accumGreenBits, accumBlueBits, accumAlphaBits number
 200  * of bits per color component in accum buffer.
 201  * \param indexBits number of bits per pixel if \p rgbFlag is GL_FALSE
 202  * \param redBits number of bits per color component in frame buffer for RGB(A)
 203  * mode.  We always use 8 in core Mesa though.
 204  * \param greenBits same as above.
 205  * \param blueBits same as above.
 206  * \param alphaBits same as above.
 207  * \param numSamples not really used.
 208  *
 209  * \return pointer to new struct gl_config or NULL if requested parameters
 210  * can't be met.
 211  *
 212  * \note Need to add params for level and numAuxBuffers (at least)
 213  */
 214 struct gl_config *
 215 _mesa_create_visual( GLboolean dbFlag,
 216                      GLboolean stereoFlag,
 217                      GLint redBits,
 218                      GLint greenBits,
 219                      GLint blueBits,
 220                      GLint alphaBits,
 221                      GLint depthBits,
 222                      GLint stencilBits,
 223                      GLint accumRedBits,
 224                      GLint accumGreenBits,
 225                      GLint accumBlueBits,
 226                      GLint accumAlphaBits,
 227                      GLint numSamples )
 228 {
 229    struct gl_config *vis = CALLOC_STRUCT(gl_config);
 230    if (vis) {
 231       if (!_mesa_initialize_visual(vis, dbFlag, stereoFlag,
 232                                    redBits, greenBits, blueBits, alphaBits,
 233                                    depthBits, stencilBits,
 234                                    accumRedBits, accumGreenBits,
 235                                    accumBlueBits, accumAlphaBits,
 236                                    numSamples)) {
 237          free(vis);
 238          return NULL;
 239       }
 240    }
 241    return vis;
 242 }
 243
 244
 245 /**
 246  * Makes some sanity checks and fills in the fields of the struct
 247  * gl_config object with the given parameters.  If the caller needs to
 248  * set additional fields, he should just probably init the whole
 249  * gl_config object himself.
 250  *
 251  * \return GL_TRUE on success, or GL_FALSE on failure.
 252  *
 253  * \sa _mesa_create_visual() above for the parameter description.
 254  */
 255 GLboolean
 256 _mesa_initialize_visual( struct gl_config *vis,
 257                          GLboolean dbFlag,
 258                          GLboolean stereoFlag,
 259                          GLint redBits,
 260                          GLint greenBits,
 261                          GLint blueBits,
 262                          GLint alphaBits,
 263                          GLint depthBits,
 264                          GLint stencilBits,
 265                          GLint accumRedBits,
 266                          GLint accumGreenBits,
 267                          GLint accumBlueBits,
 268                          GLint accumAlphaBits,
 269                          GLint numSamples )
 270 {
 271    assert(vis);
 272
 273    if (depthBits < 0 || depthBits > 32) {
 274       return GL_FALSE;
 275    }
 276    if (stencilBits < 0 || stencilBits > 8) {
 277       return GL_FALSE;
 278    }
 279    assert(accumRedBits >= 0);
 280    assert(accumGreenBits >= 0);
 281    assert(accumBlueBits >= 0);
 282    assert(accumAlphaBits >= 0);
 283
 284    vis->rgbMode          = GL_TRUE;
 285    vis->doubleBufferMode = dbFlag;
 286    vis->stereoMode       = stereoFlag;
 287
 288    vis->redBits          = redBits;
 289    vis->greenBits        = greenBits;
 290    vis->blueBits         = blueBits;
 291    vis->alphaBits        = alphaBits;
 292    vis->rgbBits          = redBits + greenBits + blueBits;
 293
 294    vis->indexBits      = 0;
 295    vis->depthBits      = depthBits;
 296    vis->stencilBits    = stencilBits;
 297
 298    vis->accumRedBits   = accumRedBits;
 299    vis->accumGreenBits = accumGreenBits;
 300    vis->accumBlueBits  = accumBlueBits;
 301    vis->accumAlphaBits = accumAlphaBits;
 302
 303    vis->haveAccumBuffer   = accumRedBits > 0;
 304    vis->haveDepthBuffer   = depthBits > 0;
 305    vis->haveStencilBuffer = stencilBits > 0;
 306
 307    vis->numAuxBuffers = 0;
 308    vis->level = 0;
 309    vis->sampleBuffers = numSamples > 0 ? 1 : 0;
 310    vis->samples = numSamples;
 311
 312    return GL_TRUE;
 313 }
 314
 315
 316 /**
 317  * Destroy a visual and free its memory.
 318  *
 319  * \param vis visual.
 320  *
 321  * Frees the visual structure.
 322  */
 323 void
 324 _mesa_destroy_visual( struct gl_config *vis )
 325 {
 326    free(vis);
 327 }
 328
 329 /*@}*/
 330
 331
 332 /**********************************************************************/
 333 /** \name Context allocation, initialization, destroying
 334  *
 335  * The purpose of the most initialization functions here is to provide the
 336  * default state values according to the OpenGL specification.
 337  */
 338 /**********************************************************************/
 339 /*@{*/
 340
 341
 342 /**
 343  * One-time initialization mutex lock.
 344  *
 345  * \sa Used by one_time_init().
 346  */
 347 mtx_t OneTimeLock = _MTX_INITIALIZER_NP;
 348
 349
 350 /**
 351  * Calls all the various one-time-fini functions in Mesa
 352  */
 353
 354 static void
 355 one_time_fini(void)
 356 {
 357    _mesa_destroy_shader_compiler();
 358    _mesa_locale_fini();
 359 }
 360
 361 /**
 362  * Calls all the various one-time-init functions in Mesa.
 363  *
 364  * While holding a global mutex lock, calls several initialization functions,
 365  * and sets the glapi callbacks if the \c MESA_DEBUG environment variable is
 366  * defined.
 367  *
 368  * \sa _math_init().
 369  */
 370 static void
 371 one_time_init( struct gl_context *ctx )
 372 {
 373    static GLbitfield api_init_mask = 0x0;
 374
 375    mtx_lock(&OneTimeLock);
 376
 377    /* truly one-time init */
 378    if (!api_init_mask) {
 379       GLuint i;
 380
 381       STATIC_ASSERT(sizeof(GLbyte) == 1);
 382       STATIC_ASSERT(sizeof(GLubyte) == 1);
 383       STATIC_ASSERT(sizeof(GLshort) == 2);
 384       STATIC_ASSERT(sizeof(GLushort) == 2);
 385       STATIC_ASSERT(sizeof(GLint) == 4);
 386       STATIC_ASSERT(sizeof(GLuint) == 4);
 387
 388       _mesa_locale_init();
 389
 390       _mesa_one_time_init_extension_overrides();
 391
 392       _mesa_get_cpu_features();
 393
 394       for (i = 0; i < 256; i++) {
 395          _mesa_ubyte_to_float_color_tab[i] = (float) i / 255.0F;
 396       }
 397
 398       atexit(one_time_fini);
 399
 400 #if defined(DEBUG) && defined(__DATE__) && defined(__TIME__)
 401       if (MESA_VERBOSE != 0) {
 402          _mesa_debug(ctx, "Mesa %s DEBUG build %s %s\n",
 403                      PACKAGE_VERSION, __DATE__, __TIME__);
 404       }
 405 #endif
 406    }
 407
 408    /* per-API one-time init */
 409    if (!(api_init_mask & (1 << ctx->API))) {
 410       _mesa_init_get_hash(ctx);
 411
 412       _mesa_init_remap_table();
 413    }
 414
 415    api_init_mask |= 1 << ctx->API;
 416
 417    mtx_unlock(&OneTimeLock);
 418 }
 419
 420
 421 /**
 422  * Initialize fields of gl_current_attrib (aka ctx->Current.*)
 423  */
 424 static void
 425 _mesa_init_current(struct gl_context *ctx)
 426 {
 427    GLuint i;
 428
 429    /* Init all to (0,0,0,1) */
 430    for (i = 0; i < ARRAY_SIZE(ctx->Current.Attrib); i++) {
 431       ASSIGN_4V( ctx->Current.Attrib[i], 0.0, 0.0, 0.0, 1.0 );
 432    }
 433
 434    /* redo special cases: */
 435    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_WEIGHT], 1.0, 0.0, 0.0, 0.0 );
 436    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_NORMAL], 0.0, 0.0, 1.0, 1.0 );
 437    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR0], 1.0, 1.0, 1.0, 1.0 );
 438    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR1], 0.0, 0.0, 0.0, 1.0 );
 439    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR_INDEX], 1.0, 0.0, 0.0, 1.0 );
 440    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_EDGEFLAG], 1.0, 0.0, 0.0, 1.0 );
 441 }
 442
 443
 444 /**
 445  * Init vertex/fragment/geometry program limits.
 446  * Important: drivers should override these with actual limits.
 447  */
 448 static void
 449 init_program_limits(struct gl_constants *consts, gl_shader_stage stage,
 450                     struct gl_program_constants *prog)
 451 {
 452    prog->MaxInstructions = MAX_PROGRAM_INSTRUCTIONS;
 453    prog->MaxAluInstructions = MAX_PROGRAM_INSTRUCTIONS;
 454    prog->MaxTexInstructions = MAX_PROGRAM_INSTRUCTIONS;
 455    prog->MaxTexIndirections = MAX_PROGRAM_INSTRUCTIONS;
 456    prog->MaxTemps = MAX_PROGRAM_TEMPS;
 457    prog->MaxEnvParams = MAX_PROGRAM_ENV_PARAMS;
 458    prog->MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
 459    prog->MaxAddressOffset = MAX_PROGRAM_LOCAL_PARAMS;
 460
 461    switch (stage) {
 462    case MESA_SHADER_VERTEX:
 463       prog->MaxParameters = MAX_VERTEX_PROGRAM_PARAMS;
 464       prog->MaxAttribs = MAX_VERTEX_GENERIC_ATTRIBS;
 465       prog->MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 466       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 467       prog->MaxInputComponents = 0; /* value not used */
 468       prog->MaxOutputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 469       break;
 470    case MESA_SHADER_FRAGMENT:
 471       prog->MaxParameters = MAX_FRAGMENT_PROGRAM_PARAMS;
 472       prog->MaxAttribs = MAX_FRAGMENT_PROGRAM_INPUTS;
 473       prog->MaxAddressRegs = MAX_FRAGMENT_PROGRAM_ADDRESS_REGS;
 474       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 475       prog->MaxInputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 476       prog->MaxOutputComponents = 0; /* value not used */
 477       break;
 478    case MESA_SHADER_TESS_CTRL:
 479    case MESA_SHADER_TESS_EVAL:
 480    case MESA_SHADER_GEOMETRY:
 481       prog->MaxParameters = MAX_VERTEX_PROGRAM_PARAMS;
 482       prog->MaxAttribs = MAX_VERTEX_GENERIC_ATTRIBS;
 483       prog->MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 484       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 485       prog->MaxInputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 486       prog->MaxOutputComponents = 16 * 4; /* old limit not to break tnl and swrast */
 487       break;
 488    case MESA_SHADER_COMPUTE:
 489       prog->MaxParameters = 0; /* not meaningful for compute shaders */
 490       prog->MaxAttribs = 0; /* not meaningful for compute shaders */
 491       prog->MaxAddressRegs = 0; /* not meaningful for compute shaders */
 492       prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 493       prog->MaxInputComponents = 0; /* not meaningful for compute shaders */
 494       prog->MaxOutputComponents = 0; /* not meaningful for compute shaders */
 495       break;
 496    default:
 497       assert(0 && "Bad shader stage in init_program_limits()");
 498    }
 499
 500    /* Set the native limits to zero.  This implies that there is no native
 501     * support for shaders.  Let the drivers fill in the actual values.
 502     */
 503    prog->MaxNativeInstructions = 0;
 504    prog->MaxNativeAluInstructions = 0;
 505    prog->MaxNativeTexInstructions = 0;
 506    prog->MaxNativeTexIndirections = 0;
 507    prog->MaxNativeAttribs = 0;
 508    prog->MaxNativeTemps = 0;
 509    prog->MaxNativeAddressRegs = 0;
 510    prog->MaxNativeParameters = 0;
 511
 512    /* Set GLSL datatype range/precision info assuming IEEE float values.
 513     * Drivers should override these defaults as needed.
 514     */
 515    prog->MediumFloat.RangeMin = 127;
 516    prog->MediumFloat.RangeMax = 127;
 517    prog->MediumFloat.Precision = 23;
 518    prog->LowFloat = prog->HighFloat = prog->MediumFloat;
 519
 520    /* Assume ints are stored as floats for now, since this is the least-common
 521     * denominator.  The OpenGL ES spec implies (page 132) that the precision
 522     * of integer types should be 0.  Practically speaking, IEEE
 523     * single-precision floating point values can only store integers in the
 524     * range [-0x01000000, 0x01000000] without loss of precision.
 525     */
 526    prog->MediumInt.RangeMin = 24;
 527    prog->MediumInt.RangeMax = 24;
 528    prog->MediumInt.Precision = 0;
 529    prog->LowInt = prog->HighInt = prog->MediumInt;
 530
 531    prog->MaxUniformBlocks = 12;
 532    prog->MaxCombinedUniformComponents = (prog->MaxUniformComponents +
 533                                          consts->MaxUniformBlockSize / 4 *
 534                                          prog->MaxUniformBlocks);
 535
 536    prog->MaxAtomicBuffers = 0;
 537    prog->MaxAtomicCounters = 0;
 538
 539    prog->MaxShaderStorageBlocks = 8;
 540 }
 541
 542
 543 /**
 544  * Initialize fields of gl_constants (aka ctx->Const.*).
 545  * Use defaults from config.h.  The device drivers will often override
 546  * some of these values (such as number of texture units).
 547  */
 548 void
 549 _mesa_init_constants(struct gl_constants *consts, gl_api api)
 550 {
 551    int i;
 552    assert(consts);
 553
 554    /* Constants, may be overriden (usually only reduced) by device drivers */
 555    consts->MaxTextureMbytes = MAX_TEXTURE_MBYTES;
 556    consts->MaxTextureLevels = MAX_TEXTURE_LEVELS;
 557    consts->Max3DTextureLevels = MAX_3D_TEXTURE_LEVELS;
 558    consts->MaxCubeTextureLevels = MAX_CUBE_TEXTURE_LEVELS;
 559    consts->MaxTextureRectSize = MAX_TEXTURE_RECT_SIZE;
 560    consts->MaxArrayTextureLayers = MAX_ARRAY_TEXTURE_LAYERS;
 561    consts->MaxTextureCoordUnits = MAX_TEXTURE_COORD_UNITS;
 562    consts->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 563    consts->MaxTextureUnits = MIN2(consts->MaxTextureCoordUnits,
 564                                      consts->Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits);
 565    consts->MaxTextureMaxAnisotropy = MAX_TEXTURE_MAX_ANISOTROPY;
 566    consts->MaxTextureLodBias = MAX_TEXTURE_LOD_BIAS;
 567    consts->MaxTextureBufferSize = 65536;
 568    consts->TextureBufferOffsetAlignment = 1;
 569    consts->MaxArrayLockSize = MAX_ARRAY_LOCK_SIZE;
 570    consts->SubPixelBits = SUB_PIXEL_BITS;
 571    consts->MinPointSize = MIN_POINT_SIZE;
 572    consts->MaxPointSize = MAX_POINT_SIZE;
 573    consts->MinPointSizeAA = MIN_POINT_SIZE;
 574    consts->MaxPointSizeAA = MAX_POINT_SIZE;
 575    consts->PointSizeGranularity = (GLfloat) POINT_SIZE_GRANULARITY;
 576    consts->MinLineWidth = MIN_LINE_WIDTH;
 577    consts->MaxLineWidth = MAX_LINE_WIDTH;
 578    consts->MinLineWidthAA = MIN_LINE_WIDTH;
 579    consts->MaxLineWidthAA = MAX_LINE_WIDTH;
 580    consts->LineWidthGranularity = (GLfloat) LINE_WIDTH_GRANULARITY;
 581    consts->MaxClipPlanes = 6;
 582    consts->MaxLights = MAX_LIGHTS;
 583    consts->MaxShininess = 128.0;
 584    consts->MaxSpotExponent = 128.0;
 585    consts->MaxViewportWidth = MAX_VIEWPORT_WIDTH;
 586    consts->MaxViewportHeight = MAX_VIEWPORT_HEIGHT;
 587    consts->MinMapBufferAlignment = 64;
 588
 589    /* Driver must override these values if ARB_viewport_array is supported. */
 590    consts->MaxViewports = 1;
 591    consts->ViewportSubpixelBits = 0;
 592    consts->ViewportBounds.Min = 0;
 593    consts->ViewportBounds.Max = 0;
 594
 595    /** GL_ARB_uniform_buffer_object */
 596    consts->MaxCombinedUniformBlocks = 36;
 597    consts->MaxUniformBufferBindings = 36;
 598    consts->MaxUniformBlockSize = 16384;
 599    consts->UniformBufferOffsetAlignment = 1;
 600
 601    /** GL_ARB_shader_storage_buffer_object */
 602    consts->MaxCombinedShaderStorageBlocks = 8;
 603    consts->MaxShaderStorageBufferBindings = 8;
 604    consts->MaxShaderStorageBlockSize = 128 * 1024 * 1024; /* 2^27 */
 605    consts->ShaderStorageBufferOffsetAlignment = 256;
 606
 607    /* GL_ARB_explicit_uniform_location, GL_MAX_UNIFORM_LOCATIONS */
 608    consts->MaxUserAssignableUniformLocations =
 609       4 * MESA_SHADER_STAGES * MAX_UNIFORMS;
 610
 611    for (i = 0; i < MESA_SHADER_STAGES; i++)
 612       init_program_limits(consts, i, &consts->Program[i]);
 613
 614    consts->MaxProgramMatrices = MAX_PROGRAM_MATRICES;
 615    consts->MaxProgramMatrixStackDepth = MAX_PROGRAM_MATRIX_STACK_DEPTH;
 616
 617    /* Assume that if GLSL 1.30+ (or GLSL ES 3.00+) is supported that
 618     * gl_VertexID is implemented using a native hardware register with OpenGL
 619     * semantics.
 620     */
 621    consts->VertexID_is_zero_based = false;
 622
 623    /* GL_ARB_draw_buffers */
 624    consts->MaxDrawBuffers = MAX_DRAW_BUFFERS;
 625
 626    consts->MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
 627    consts->MaxRenderbufferSize = MAX_RENDERBUFFER_SIZE;
 628
 629    consts->Program[MESA_SHADER_VERTEX].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 630    consts->MaxCombinedTextureImageUnits = MAX_COMBINED_TEXTURE_IMAGE_UNITS;
 631    consts->MaxVarying = 16; /* old limit not to break tnl and swrast */
 632    consts->Program[MESA_SHADER_GEOMETRY].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 633    consts->MaxGeometryOutputVertices = MAX_GEOMETRY_OUTPUT_VERTICES;
 634    consts->MaxGeometryTotalOutputComponents = MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS;
 635
 636    /* Shading language version */
 637    consts->GLSLVersion = 120;
 638    _mesa_override_glsl_version(consts);
 639
 640 #ifdef DEBUG
 641    consts->GenerateTemporaryNames = true;
 642 #else
 643    consts->GenerateTemporaryNames = false;
 644 #endif
 645
 646    /* GL_ARB_framebuffer_object */
 647    consts->MaxSamples = 0;
 648
 649    /* GLSL default if NativeIntegers == FALSE */
 650    consts->UniformBooleanTrue = FLOAT_AS_UNION(1.0f).u;
 651
 652    /* GL_ARB_sync */
 653    consts->MaxServerWaitTimeout = 0x1fff7fffffffULL;
 654
 655    /* GL_EXT_provoking_vertex */
 656    consts->QuadsFollowProvokingVertexConvention = GL_TRUE;
 657
 658    /** GL_ARB_viewport_array */
 659    consts->LayerAndVPIndexProvokingVertex = GL_UNDEFINED_VERTEX;
 660
 661    /* GL_EXT_transform_feedback */
 662    consts->MaxTransformFeedbackBuffers = MAX_FEEDBACK_BUFFERS;
 663    consts->MaxTransformFeedbackSeparateComponents = 4 * MAX_FEEDBACK_ATTRIBS;
 664    consts->MaxTransformFeedbackInterleavedComponents = 4 * MAX_FEEDBACK_ATTRIBS;
 665    consts->MaxVertexStreams = 1;
 666
 667    /* GL 3.2  */
 668    consts->ProfileMask = api == API_OPENGL_CORE
 669                           ? GL_CONTEXT_CORE_PROFILE_BIT
 670                           : GL_CONTEXT_COMPATIBILITY_PROFILE_BIT;
 671
 672    /* GL 4.4 */
 673    consts->MaxVertexAttribStride = 2048;
 674
 675    /** GL_EXT_gpu_shader4 */
 676    consts->MinProgramTexelOffset = -8;
 677    consts->MaxProgramTexelOffset = 7;
 678
 679    /* GL_ARB_texture_gather */
 680    consts->MinProgramTextureGatherOffset = -8;
 681    consts->MaxProgramTextureGatherOffset = 7;
 682
 683    /* GL_ARB_robustness */
 684    consts->ResetStrategy = GL_NO_RESET_NOTIFICATION_ARB;
 685
 686    /* ES 3.0 or ARB_ES3_compatibility */
 687    consts->MaxElementIndex = 0xffffffffu;
 688
 689    /* GL_ARB_texture_multisample */
 690    consts->MaxColorTextureSamples = 1;
 691    consts->MaxDepthTextureSamples = 1;
 692    consts->MaxIntegerSamples = 1;
 693
 694    /* GL_ARB_shader_atomic_counters */
 695    consts->MaxAtomicBufferBindings = MAX_COMBINED_ATOMIC_BUFFERS;
 696    consts->MaxAtomicBufferSize = MAX_ATOMIC_COUNTERS * ATOMIC_COUNTER_SIZE;
 697    consts->MaxCombinedAtomicBuffers = MAX_COMBINED_ATOMIC_BUFFERS;
 698    consts->MaxCombinedAtomicCounters = MAX_ATOMIC_COUNTERS;
 699
 700    /* GL_ARB_vertex_attrib_binding */
 701    consts->MaxVertexAttribRelativeOffset = 2047;
 702    consts->MaxVertexAttribBindings = MAX_VERTEX_GENERIC_ATTRIBS;
 703
 704    /* GL_ARB_compute_shader */
 705    consts->MaxComputeWorkGroupCount[0] = 65535;
 706    consts->MaxComputeWorkGroupCount[1] = 65535;
 707    consts->MaxComputeWorkGroupCount[2] = 65535;
 708    consts->MaxComputeWorkGroupSize[0] = 1024;
 709    consts->MaxComputeWorkGroupSize[1] = 1024;
 710    consts->MaxComputeWorkGroupSize[2] = 64;
 711    consts->MaxComputeWorkGroupInvocations = 1024;
 712
 713    /** GL_ARB_gpu_shader5 */
 714    consts->MinFragmentInterpolationOffset = MIN_FRAGMENT_INTERPOLATION_OFFSET;
 715    consts->MaxFragmentInterpolationOffset = MAX_FRAGMENT_INTERPOLATION_OFFSET;
 716
 717    /** GL_KHR_context_flush_control */
 718    consts->ContextReleaseBehavior = GL_CONTEXT_RELEASE_BEHAVIOR_FLUSH;
 719
 720    /** GL_ARB_tessellation_shader */
 721    consts->MaxTessGenLevel = MAX_TESS_GEN_LEVEL;
 722    consts->MaxPatchVertices = MAX_PATCH_VERTICES;
 723    consts->Program[MESA_SHADER_TESS_CTRL].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 724    consts->Program[MESA_SHADER_TESS_EVAL].MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 725    consts->MaxTessPatchComponents = MAX_TESS_PATCH_COMPONENTS;
 726    consts->MaxTessControlTotalOutputComponents = MAX_TESS_CONTROL_TOTAL_OUTPUT_COMPONENTS;
 727 }
 728
 729
 730 /**
 731  * Do some sanity checks on the limits/constants for the given context.
 732  * Only called the first time a context is bound.
 733  */
 734 static void
 735 check_context_limits(struct gl_context *ctx)
 736 {
 737    (void) ctx;
 738
 739    /* check that we don't exceed the size of various bitfields */
 740    assert(VARYING_SLOT_MAX <=
 741           (8 * sizeof(ctx->VertexProgram._Current->Base.OutputsWritten)));
 742    assert(VARYING_SLOT_MAX <=
 743           (8 * sizeof(ctx->FragmentProgram._Current->Base.InputsRead)));
 744
 745    /* shader-related checks */
 746    assert(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 747    assert(ctx->Const.Program[MESA_SHADER_VERTEX].MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 748
 749    /* Texture unit checks */
 750    assert(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits > 0);
 751    assert(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 752    assert(ctx->Const.MaxTextureCoordUnits > 0);
 753    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 754    assert(ctx->Const.MaxTextureUnits > 0);
 755    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 756    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 757    assert(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits,
 758                                              ctx->Const.MaxTextureCoordUnits));
 759    assert(ctx->Const.MaxCombinedTextureImageUnits > 0);
 760    assert(ctx->Const.MaxCombinedTextureImageUnits <= MAX_COMBINED_TEXTURE_IMAGE_UNITS);
 761    assert(ctx->Const.MaxTextureCoordUnits <= MAX_COMBINED_TEXTURE_IMAGE_UNITS);
 762    /* number of coord units cannot be greater than number of image units */
 763    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxTextureImageUnits);
 764
 765
 766    /* Texture size checks */
 767    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 768    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 769    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 770    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 771
 772    /* Texture level checks */
 773    assert(MAX_TEXTURE_LEVELS >= MAX_3D_TEXTURE_LEVELS);
 774    assert(MAX_TEXTURE_LEVELS >= MAX_CUBE_TEXTURE_LEVELS);
 775
 776    /* Max texture size should be <= max viewport size (render to texture) */
 777    assert((1U << (ctx->Const.MaxTextureLevels - 1))
 778           <= ctx->Const.MaxViewportWidth);
 779    assert((1U << (ctx->Const.MaxTextureLevels - 1))
 780           <= ctx->Const.MaxViewportHeight);
 781
 782    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 783
 784    /* if this fails, add more enum values to gl_buffer_index */
 785    assert(BUFFER_COLOR0 + MAX_DRAW_BUFFERS <= BUFFER_COUNT);
 786
 787    /* XXX probably add more tests */
 788 }
 789
 790
 791 /**
 792  * Initialize the attribute groups in a GL context.
 793  *
 794  * \param ctx GL context.
 795  *
 796  * Initializes all the attributes, calling the respective <tt>init*</tt>
 797  * functions for the more complex data structures.
 798  */
 799 static GLboolean
 800 init_attrib_groups(struct gl_context *ctx)
 801 {
 802    assert(ctx);
 803
 804    /* Constants */
 805    _mesa_init_constants(&ctx->Const, ctx->API);
 806
 807    /* Extensions */
 808    _mesa_init_extensions(&ctx->Extensions);
 809
 810    /* Attribute Groups */
 811    _mesa_init_accum( ctx );
 812    _mesa_init_attrib( ctx );
 813    _mesa_init_buffer_objects( ctx );
 814    _mesa_init_color( ctx );
 815    _mesa_init_current( ctx );
 816    _mesa_init_depth( ctx );
 817    _mesa_init_debug( ctx );
 818    _mesa_init_debug_output( ctx );
 819    _mesa_init_display_list( ctx );
 820    _mesa_init_eval( ctx );
 821    _mesa_init_fbobjects( ctx );
 822    _mesa_init_feedback( ctx );
 823    _mesa_init_fog( ctx );
 824    _mesa_init_hint( ctx );
 825    _mesa_init_image_units( ctx );
 826    _mesa_init_line( ctx );
 827    _mesa_init_lighting( ctx );
 828    _mesa_init_matrix( ctx );
 829    _mesa_init_multisample( ctx );
 830    _mesa_init_performance_monitors( ctx );
 831    _mesa_init_pipeline( ctx );
 832    _mesa_init_pixel( ctx );
 833    _mesa_init_pixelstore( ctx );
 834    _mesa_init_point( ctx );
 835    _mesa_init_polygon( ctx );
 836    _mesa_init_program( ctx );
 837    _mesa_init_queryobj( ctx );
 838    _mesa_init_sync( ctx );
 839    _mesa_init_rastpos( ctx );
 840    _mesa_init_scissor( ctx );
 841    _mesa_init_shader_state( ctx );
 842    _mesa_init_stencil( ctx );
 843    _mesa_init_transform( ctx );
 844    _mesa_init_transform_feedback( ctx );
 845    _mesa_init_varray( ctx );
 846    _mesa_init_viewport( ctx );
 847
 848    if (!_mesa_init_texture( ctx ))
 849       return GL_FALSE;
 850
 851    _mesa_init_texture_s3tc( ctx );
 852
 853    /* Miscellaneous */
 854    ctx->NewState = _NEW_ALL;
 855    ctx->NewDriverState = ~0;
 856    ctx->ErrorValue = GL_NO_ERROR;
 857    ctx->ShareGroupReset = false;
 858    ctx->varying_vp_inputs = VERT_BIT_ALL;
 859
 860    return GL_TRUE;
 861 }
 862
 863
 864 /**
 865  * Update default objects in a GL context with respect to shared state.
 866  *
 867  * \param ctx GL context.
 868  *
 869  * Removes references to old default objects, (texture objects, program
 870  * objects, etc.) and changes to reference those from the current shared
 871  * state.
 872  */
 873 static GLboolean
 874 update_default_objects(struct gl_context *ctx)
 875 {
 876    assert(ctx);
 877
 878    _mesa_update_default_objects_program(ctx);
 879    _mesa_update_default_objects_texture(ctx);
 880    _mesa_update_default_objects_buffer_objects(ctx);
 881
 882    return GL_TRUE;
 883 }
 884
 885
 886 /* XXX this is temporary and should be removed at some point in the
 887  * future when there's a reasonable expectation that the libGL library
 888  * contains the _glapi_new_nop_table() and _glapi_set_nop_handler()
 889  * functions which were added in Mesa 10.6.
 890  */
 891 #if !defined(_WIN32)
 892 /* Avoid libGL / driver ABI break */
 893 #define USE_GLAPI_NOP_FEATURES 0
 894 #else
 895 #define USE_GLAPI_NOP_FEATURES 1
 896 #endif
 897
 898
 899 /**
 900  * This function is called by the glapi no-op functions.  For each OpenGL
 901  * function/entrypoint there's a simple no-op function.  These "no-op"
 902  * functions call this function.
 903  *
 904  * If there's a current OpenGL context for the calling thread, we record a
 905  * GL_INVALID_OPERATION error.  This can happen either because the app's
 906  * calling an unsupported extension function, or calling an illegal function
 907  * (such as glClear between glBegin/glEnd).
 908  *
 909  * If there's no current OpenGL context for the calling thread, we can
 910  * print a message to stderr.
 911  *
 912  * \param name  the name of the OpenGL function
 913  */
 914 #if USE_GLAPI_NOP_FEATURES
 915 static void
 916 nop_handler(const char *name)
 917 {
 918    GET_CURRENT_CONTEXT(ctx);
 919    if (ctx) {
 920       _mesa_error(ctx, GL_INVALID_OPERATION, "%s(invalid call)", name);
 921    }
 922 #if defined(DEBUG)
 923    else if (getenv("MESA_DEBUG") || getenv("LIBGL_DEBUG")) {
 924       fprintf(stderr,
 925               "GL User Error: gl%s called without a rendering context\n",
 926               name);
 927       fflush(stderr);
 928    }
 929 #endif
 930 }
 931 #endif
 932
 933
 934 /**
 935  * Special no-op glFlush, see below.
 936  */
 937 #if defined(_WIN32)
 938 static void GLAPIENTRY
 939 nop_glFlush(void)
 940 {
 941    /* don't record an error like we do in nop_handler() */
 942 }
 943 #endif
 944
 945
 946 #if !USE_GLAPI_NOP_FEATURES
 947 static int
 948 generic_nop(void)
 949 {
 950    GET_CURRENT_CONTEXT(ctx);
 951    _mesa_error(ctx, GL_INVALID_OPERATION,
 952                "unsupported function called "
 953                "(unsupported extension or deprecated function?)");
 954    return 0;
 955 }
 956 #endif
 957
 958
 959 /**
 960  * Create a new API dispatch table in which all entries point to the
 961  * generic_nop() function.  This will not work on Windows because of
 962  * the __stdcall convention which requires the callee to clean up the
 963  * call stack.  That's impossible with one generic no-op function.
 964  */
 965 struct _glapi_table *
 966 _mesa_new_nop_table(unsigned numEntries)
 967 {
 968    struct _glapi_table *table;
 969
 970 #if !USE_GLAPI_NOP_FEATURES
 971    table = malloc(numEntries * sizeof(_glapi_proc));
 972    if (table) {
 973       _glapi_proc *entry = (_glapi_proc *) table;
 974       unsigned i;
 975       for (i = 0; i < numEntries; i++) {
 976          entry[i] = (_glapi_proc) generic_nop;
 977       }
 978    }
 979 #else
 980    table = _glapi_new_nop_table(numEntries);
 981 #endif
 982    return table;
 983 }
 984
 985
 986 /**
 987  * Allocate and initialize a new dispatch table.  The table will be
 988  * populated with pointers to "no-op" functions.  In turn, the no-op
 989  * functions will call nop_handler() above.
 990  */
 991 static struct _glapi_table *
 992 alloc_dispatch_table(void)
 993 {
 994    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
 995     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
 996     * Mesa we do this to accommodate different versions of libGL and various
 997     * DRI drivers.
 998     */
 999    int numEntries = MAX2(_glapi_get_dispatch_table_size(), _gloffset_COUNT);
1000
1001    struct _glapi_table *table = _mesa_new_nop_table(numEntries);
1002
1003 #if defined(_WIN32)
1004    if (table) {
1005       /* This is a special case for Windows in the event that
1006        * wglGetProcAddress is called between glBegin/End().
1007        *
1008        * The MS opengl32.dll library apparently calls glFlush from
1009        * wglGetProcAddress().  If we're inside glBegin/End(), glFlush
1010        * will dispatch to _mesa_generic_nop() and we'll generate a
1011        * GL_INVALID_OPERATION error.
1012        *
1013        * The specific case which hits this is piglit's primitive-restart
1014        * test which calls glPrimitiveRestartNV() inside glBegin/End.  The
1015        * first time we call glPrimitiveRestartNV() Piglit's API dispatch
1016        * code will try to resolve the function by calling wglGetProcAddress.
1017        * This raises GL_INVALID_OPERATION and an assert(glGetError()==0)
1018        * will fail causing the test to fail.  By suppressing the error, the
1019        * assertion passes and the test continues.
1020        */
1021       SET_Flush(table, nop_glFlush);
1022    }
1023 #endif
1024
1025 #if USE_GLAPI_NOP_FEATURES
1026    _glapi_set_nop_handler(nop_handler);
1027 #endif
1028
1029    return table;
1030 }
1031
1032 /**
1033  * Creates a minimal dispatch table for use within glBegin()/glEnd().
1034  *
1035  * This ensures that we generate GL_INVALID_OPERATION errors from most
1036  * functions, since the set of functions that are valid within Begin/End is
1037  * very small.
1038  *
1039  * From the GL 1.0 specification section 2.6.3, "GL Commands within
1040  * Begin/End"
1041  *
1042  *     "The only GL commands that are allowed within any Begin/End pairs are
1043  *      the commands for specifying vertex coordinates, vertex color, normal
1044  *      coordinates, and texture coordinates (Vertex, Color, Index, Normal,
1045  *      TexCoord), EvalCoord and EvalPoint commands (see section 5.1),
1046  *      commands for specifying lighting material parameters (Material
1047  *      commands see section 2.12.2), display list invocation commands
1048  *      (CallList and CallLists see section 5.4), and the EdgeFlag
1049  *      command. Executing Begin after Begin has already been executed but
1050  *      before an End is issued generates the INVALID OPERATION error, as does
1051  *      executing End without a previous corresponding Begin. Executing any
1052  *      other GL command within Begin/End results in the error INVALID
1053  *      OPERATION."
1054  *
1055  * The table entries for specifying vertex attributes are set up by
1056  * install_vtxfmt() and _mesa_loopback_init_api_table(), and End() and dlists
1057  * are set by install_vtxfmt() as well.
1058  */
1059 static struct _glapi_table *
1060 create_beginend_table(const struct gl_context *ctx)
1061 {
1062    struct _glapi_table *table;
1063
1064    table = alloc_dispatch_table();
1065    if (!table)
1066       return NULL;
1067
1068    /* Fill in functions which return a value, since they should return some
1069     * specific value even if they emit a GL_INVALID_OPERATION error from them
1070     * being called within glBegin()/glEnd().
1071     */
1072 #define COPY_DISPATCH(func) SET_##func(table, GET_##func(ctx->Exec))
1073
1074    COPY_DISPATCH(GenLists);
1075    COPY_DISPATCH(IsProgram);
1076    COPY_DISPATCH(IsVertexArray);
1077    COPY_DISPATCH(IsBuffer);
1078    COPY_DISPATCH(IsEnabled);
1079    COPY_DISPATCH(IsEnabledi);
1080    COPY_DISPATCH(IsRenderbuffer);
1081    COPY_DISPATCH(IsFramebuffer);
1082    COPY_DISPATCH(CheckFramebufferStatus);
1083    COPY_DISPATCH(RenderMode);
1084    COPY_DISPATCH(GetString);
1085    COPY_DISPATCH(GetStringi);
1086    COPY_DISPATCH(GetPointerv);
1087    COPY_DISPATCH(IsQuery);
1088    COPY_DISPATCH(IsSampler);
1089    COPY_DISPATCH(IsSync);
1090    COPY_DISPATCH(IsTexture);
1091    COPY_DISPATCH(IsTransformFeedback);
1092    COPY_DISPATCH(DeleteQueries);
1093    COPY_DISPATCH(AreTexturesResident);
1094    COPY_DISPATCH(FenceSync);
1095    COPY_DISPATCH(ClientWaitSync);
1096    COPY_DISPATCH(MapBuffer);
1097    COPY_DISPATCH(UnmapBuffer);
1098    COPY_DISPATCH(MapBufferRange);
1099    COPY_DISPATCH(ObjectPurgeableAPPLE);
1100    COPY_DISPATCH(ObjectUnpurgeableAPPLE);
1101
1102    _mesa_loopback_init_api_table(ctx, table);
1103
1104    return table;
1105 }
1106
1107 void
1108 _mesa_initialize_dispatch_tables(struct gl_context *ctx)
1109 {
1110    /* Do the code-generated setup of the exec table in api_exec.c. */
1111    _mesa_initialize_exec_table(ctx);
1112
1113    if (ctx->Save)
1114       _mesa_initialize_save_table(ctx);
1115 }
1116
1117 /**
1118  * Initialize a struct gl_context struct (rendering context).
1119  *
1120  * This includes allocating all the other structs and arrays which hang off of
1121  * the context by pointers.
1122  * Note that the driver needs to pass in its dd_function_table here since
1123  * we need to at least call driverFunctions->NewTextureObject to create the
1124  * default texture objects.
1125  *
1126  * Called by _mesa_create_context().
1127  *
1128  * Performs the imports and exports callback tables initialization, and
1129  * miscellaneous one-time initializations. If no shared context is supplied one
1130  * is allocated, and increase its reference count.  Setups the GL API dispatch
1131  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
1132  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
1133  * for debug flags.
1134  *
1135  * \param ctx the context to initialize
1136  * \param api the GL API type to create the context for
1137  * \param visual describes the visual attributes for this context or NULL to
1138  *               create a configless context
1139  * \param share_list points to context to share textures, display lists,
1140  *        etc with, or NULL
1141  * \param driverFunctions table of device driver functions for this context
1142  *        to use
1143  */
1144 GLboolean
1145 _mesa_initialize_context(struct gl_context *ctx,
1146                          gl_api api,
1147                          const struct gl_config *visual,
1148                          struct gl_context *share_list,
1149                          const struct dd_function_table *driverFunctions)
1150 {
1151    struct gl_shared_state *shared;
1152    int i;
1153
1154    assert(driverFunctions->NewTextureObject);
1155    assert(driverFunctions->FreeTextureImageBuffer);
1156
1157    ctx->API = api;
1158    ctx->DrawBuffer = NULL;
1159    ctx->ReadBuffer = NULL;
1160    ctx->WinSysDrawBuffer = NULL;
1161    ctx->WinSysReadBuffer = NULL;
1162
1163    if (visual) {
1164       ctx->Visual = *visual;
1165       ctx->HasConfig = GL_TRUE;
1166    }
1167    else {
1168       memset(&ctx->Visual, 0, sizeof ctx->Visual);
1169       ctx->HasConfig = GL_FALSE;
1170    }
1171
1172    _mesa_override_gl_version(ctx);
1173
1174    /* misc one-time initializations */
1175    one_time_init(ctx);
1176
1177    /* Plug in driver functions and context pointer here.
1178     * This is important because when we call alloc_shared_state() below
1179     * we'll call ctx->Driver.NewTextureObject() to create the default
1180     * textures.
1181     */
1182    ctx->Driver = *driverFunctions;
1183
1184    if (share_list) {
1185       /* share state with another context */
1186       shared = share_list->Shared;
1187    }
1188    else {
1189       /* allocate new, unshared state */
1190       shared = _mesa_alloc_shared_state(ctx);
1191       if (!shared)
1192          return GL_FALSE;
1193    }
1194
1195    _mesa_reference_shared_state(ctx, &ctx->Shared, shared);
1196
1197    if (!init_attrib_groups( ctx ))
1198       goto fail;
1199
1200    /* setup the API dispatch tables with all nop functions */
1201    ctx->OutsideBeginEnd = alloc_dispatch_table();
1202    if (!ctx->OutsideBeginEnd)
1203       goto fail;
1204    ctx->Exec = ctx->OutsideBeginEnd;
1205    ctx->CurrentDispatch = ctx->OutsideBeginEnd;
1206
1207    ctx->FragmentProgram._MaintainTexEnvProgram
1208       = (getenv("MESA_TEX_PROG") != NULL);
1209
1210    ctx->VertexProgram._MaintainTnlProgram
1211       = (getenv("MESA_TNL_PROG") != NULL);
1212    if (ctx->VertexProgram._MaintainTnlProgram) {
1213       /* this is required... */
1214       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
1215    }
1216
1217    /* Mesa core handles all the formats that mesa core knows about.
1218     * Drivers will want to override this list with just the formats
1219     * they can handle, and confirm that appropriate fallbacks exist in
1220     * _mesa_choose_tex_format().
1221     */
1222    memset(&ctx->TextureFormatSupported, GL_TRUE,
1223           sizeof(ctx->TextureFormatSupported));
1224
1225    switch (ctx->API) {
1226    case API_OPENGL_COMPAT:
1227       ctx->BeginEnd = create_beginend_table(ctx);
1228       ctx->Save = alloc_dispatch_table();
1229       if (!ctx->BeginEnd || !ctx->Save)
1230          goto fail;
1231
1232       /* fall-through */
1233    case API_OPENGL_CORE:
1234       break;
1235    case API_OPENGLES:
1236       /**
1237        * GL_OES_texture_cube_map says
1238        * "Initially all texture generation modes are set to REFLECTION_MAP_OES"
1239        */
1240       for (i = 0; i < MAX_TEXTURE_UNITS; i++) {
1241          struct gl_texture_unit *texUnit = &ctx->Texture.Unit[i];
1242          texUnit->GenS.Mode = GL_REFLECTION_MAP_NV;
1243          texUnit->GenT.Mode = GL_REFLECTION_MAP_NV;
1244          texUnit->GenR.Mode = GL_REFLECTION_MAP_NV;
1245          texUnit->GenS._ModeBit = TEXGEN_REFLECTION_MAP_NV;
1246          texUnit->GenT._ModeBit = TEXGEN_REFLECTION_MAP_NV;
1247          texUnit->GenR._ModeBit = TEXGEN_REFLECTION_MAP_NV;
1248       }
1249       break;
1250    case API_OPENGLES2:
1251       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
1252       ctx->VertexProgram._MaintainTnlProgram = GL_TRUE;
1253       break;
1254    }
1255
1256    ctx->FirstTimeCurrent = GL_TRUE;
1257
1258    return GL_TRUE;
1259
1260 fail:
1261    _mesa_reference_shared_state(ctx, &ctx->Shared, NULL);
1262    free(ctx->BeginEnd);
1263    free(ctx->OutsideBeginEnd);
1264    free(ctx->Save);
1265    return GL_FALSE;
1266 }
1267
1268
1269 /**
1270  * Allocate and initialize a struct gl_context structure.
1271  * Note that the driver needs to pass in its dd_function_table here since
1272  * we need to at least call driverFunctions->NewTextureObject to initialize
1273  * the rendering context.
1274  *
1275  * \param api the GL API type to create the context for
1276  * \param visual a struct gl_config pointer (we copy the struct contents) or
1277  *               NULL to create a configless context
1278  * \param share_list another context to share display lists with or NULL
1279  * \param driverFunctions points to the dd_function_table into which the
1280  *        driver has plugged in all its special functions.
1281  *
1282  * \return pointer to a new __struct gl_contextRec or NULL if error.
1283  */
1284 struct gl_context *
1285 _mesa_create_context(gl_api api,
1286                      const struct gl_config *visual,
1287                      struct gl_context *share_list,
1288                      const struct dd_function_table *driverFunctions)
1289 {
1290    struct gl_context *ctx;
1291
1292    ctx = calloc(1, sizeof(struct gl_context));
1293    if (!ctx)
1294       return NULL;
1295
1296    if (_mesa_initialize_context(ctx, api, visual, share_list,
1297                                 driverFunctions)) {
1298       return ctx;
1299    }
1300    else {
1301       free(ctx);
1302       return NULL;
1303    }
1304 }
1305
1306
1307 /**
1308  * Free the data associated with the given context.
1309  *
1310  * But doesn't free the struct gl_context struct itself.
1311  *
1312  * \sa _mesa_initialize_context() and init_attrib_groups().
1313  */
1314 void
1315 _mesa_free_context_data( struct gl_context *ctx )
1316 {
1317    if (!_mesa_get_current_context()){
1318       /* No current context, but we may need one in order to delete
1319        * texture objs, etc.  So temporarily bind the context now.
1320        */
1321       _mesa_make_current(ctx, NULL, NULL);
1322    }
1323
1324    /* unreference WinSysDraw/Read buffers */
1325    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
1326    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
1327    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
1328    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
1329
1330    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
1331    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
1332    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
1333
1334    _mesa_reference_tesscprog(ctx, &ctx->TessCtrlProgram._Current, NULL);
1335    _mesa_reference_tesseprog(ctx, &ctx->TessEvalProgram._Current, NULL);
1336    _mesa_reference_geomprog(ctx, &ctx->GeometryProgram._Current, NULL);
1337
1338    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
1339    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
1340    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
1341
1342    _mesa_reference_vao(ctx, &ctx->Array.VAO, NULL);
1343    _mesa_reference_vao(ctx, &ctx->Array.DefaultVAO, NULL);
1344
1345    _mesa_free_attrib_data(ctx);
1346    _mesa_free_buffer_objects(ctx);
1347    _mesa_free_eval_data( ctx );
1348    _mesa_free_texture_data( ctx );
1349    _mesa_free_matrix_data( ctx );
1350    _mesa_free_pipeline_data(ctx);
1351    _mesa_free_program_data(ctx);
1352    _mesa_free_shader_state(ctx);
1353    _mesa_free_queryobj_data(ctx);
1354    _mesa_free_sync_data(ctx);
1355    _mesa_free_varray_data(ctx);
1356    _mesa_free_transform_feedback(ctx);
1357    _mesa_free_performance_monitors(ctx);
1358
1359    _mesa_reference_buffer_object(ctx, &ctx->Pack.BufferObj, NULL);
1360    _mesa_reference_buffer_object(ctx, &ctx->Unpack.BufferObj, NULL);
1361    _mesa_reference_buffer_object(ctx, &ctx->DefaultPacking.BufferObj, NULL);
1362    _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj, NULL);
1363
1364    /* free dispatch tables */
1365    free(ctx->BeginEnd);
1366    free(ctx->OutsideBeginEnd);
1367    free(ctx->Save);
1368
1369    /* Shared context state (display lists, textures, etc) */
1370    _mesa_reference_shared_state(ctx, &ctx->Shared, NULL);
1371
1372    /* needs to be after freeing shared state */
1373    _mesa_free_display_list_data(ctx);
1374
1375    _mesa_free_errors_data(ctx);
1376
1377    free((void *)ctx->Extensions.String);
1378
1379    free(ctx->VersionString);
1380
1381    /* unbind the context if it's currently bound */
1382    if (ctx == _mesa_get_current_context()) {
1383       _mesa_make_current(NULL, NULL, NULL);
1384    }
1385 }
1386
1387
1388 /**
1389  * Destroy a struct gl_context structure.
1390  *
1391  * \param ctx GL context.
1392  *
1393  * Calls _mesa_free_context_data() and frees the gl_context object itself.
1394  */
1395 void
1396 _mesa_destroy_context( struct gl_context *ctx )
1397 {
1398    if (ctx) {
1399       _mesa_free_context_data(ctx);
1400       free( (void *) ctx );
1401    }
1402 }
1403
1404
1405 /**
1406  * Copy attribute groups from one context to another.
1407  *
1408  * \param src source context
1409  * \param dst destination context
1410  * \param mask bitwise OR of GL_*_BIT flags
1411  *
1412  * According to the bits specified in \p mask, copies the corresponding
1413  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1414  * memcpy is not enough due to the existence of internal pointers in their data
1415  * structures.
1416  */
1417 void
1418 _mesa_copy_context( const struct gl_context *src, struct gl_context *dst,
1419                     GLuint mask )
1420 {
1421    if (mask & GL_ACCUM_BUFFER_BIT) {
1422       /* OK to memcpy */
1423       dst->Accum = src->Accum;
1424    }
1425    if (mask & GL_COLOR_BUFFER_BIT) {
1426       /* OK to memcpy */
1427       dst->Color = src->Color;
1428    }
1429    if (mask & GL_CURRENT_BIT) {
1430       /* OK to memcpy */
1431       dst->Current = src->Current;
1432    }
1433    if (mask & GL_DEPTH_BUFFER_BIT) {
1434       /* OK to memcpy */
1435       dst->Depth = src->Depth;
1436    }
1437    if (mask & GL_ENABLE_BIT) {
1438       /* no op */
1439    }
1440    if (mask & GL_EVAL_BIT) {
1441       /* OK to memcpy */
1442       dst->Eval = src->Eval;
1443    }
1444    if (mask & GL_FOG_BIT) {
1445       /* OK to memcpy */
1446       dst->Fog = src->Fog;
1447    }
1448    if (mask & GL_HINT_BIT) {
1449       /* OK to memcpy */
1450       dst->Hint = src->Hint;
1451    }
1452    if (mask & GL_LIGHTING_BIT) {
1453       GLuint i;
1454       /* begin with memcpy */
1455       dst->Light = src->Light;
1456       /* fixup linked lists to prevent pointer insanity */
1457       make_empty_list( &(dst->Light.EnabledList) );
1458       for (i = 0; i < MAX_LIGHTS; i++) {
1459          if (dst->Light.Light[i].Enabled) {
1460             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1461          }
1462       }
1463    }
1464    if (mask & GL_LINE_BIT) {
1465       /* OK to memcpy */
1466       dst->Line = src->Line;
1467    }
1468    if (mask & GL_LIST_BIT) {
1469       /* OK to memcpy */
1470       dst->List = src->List;
1471    }
1472    if (mask & GL_PIXEL_MODE_BIT) {
1473       /* OK to memcpy */
1474       dst->Pixel = src->Pixel;
1475    }
1476    if (mask & GL_POINT_BIT) {
1477       /* OK to memcpy */
1478       dst->Point = src->Point;
1479    }
1480    if (mask & GL_POLYGON_BIT) {
1481       /* OK to memcpy */
1482       dst->Polygon = src->Polygon;
1483    }
1484    if (mask & GL_POLYGON_STIPPLE_BIT) {
1485       /* Use loop instead of memcpy due to problem with Portland Group's
1486        * C compiler.  Reported by John Stone.
1487        */
1488       GLuint i;
1489       for (i = 0; i < 32; i++) {
1490          dst->PolygonStipple[i] = src->PolygonStipple[i];
1491       }
1492    }
1493    if (mask & GL_SCISSOR_BIT) {
1494       /* OK to memcpy */
1495       dst->Scissor = src->Scissor;
1496    }
1497    if (mask & GL_STENCIL_BUFFER_BIT) {
1498       /* OK to memcpy */
1499       dst->Stencil = src->Stencil;
1500    }
1501    if (mask & GL_TEXTURE_BIT) {
1502       /* Cannot memcpy because of pointers */
1503       _mesa_copy_texture_state(src, dst);
1504    }
1505    if (mask & GL_TRANSFORM_BIT) {
1506       /* OK to memcpy */
1507       dst->Transform = src->Transform;
1508    }
1509    if (mask & GL_VIEWPORT_BIT) {
1510       unsigned i;
1511       for (i = 0; i < src->Const.MaxViewports; i++) {
1512          /* OK to memcpy */
1513          dst->ViewportArray[i] = src->ViewportArray[i];
1514       }
1515    }
1516
1517    /* XXX FIXME:  Call callbacks?
1518     */
1519    dst->NewState = _NEW_ALL;
1520    dst->NewDriverState = ~0;
1521 }
1522
1523
1524 /**
1525  * Check if the given context can render into the given framebuffer
1526  * by checking visual attributes.
1527  *
1528  * Most of these tests could go away because Mesa is now pretty flexible
1529  * in terms of mixing rendering contexts with framebuffers.  As long
1530  * as RGB vs. CI mode agree, we're probably good.
1531  *
1532  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1533  */
1534 static GLboolean
1535 check_compatible(const struct gl_context *ctx,
1536                  const struct gl_framebuffer *buffer)
1537 {
1538    const struct gl_config *ctxvis = &ctx->Visual;
1539    const struct gl_config *bufvis = &buffer->Visual;
1540
1541    if (buffer == _mesa_get_incomplete_framebuffer())
1542       return GL_TRUE;
1543
1544 #if 0
1545    /* disabling this fixes the fgl_glxgears pbuffer demo */
1546    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1547       return GL_FALSE;
1548 #endif
1549    if (ctxvis->stereoMode && !bufvis->stereoMode)
1550       return GL_FALSE;
1551    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1552       return GL_FALSE;
1553    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1554       return GL_FALSE;
1555    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1556       return GL_FALSE;
1557    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1558       return GL_FALSE;
1559    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1560       return GL_FALSE;
1561    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1562       return GL_FALSE;
1563 #if 0
1564    /* disabled (see bug 11161) */
1565    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1566       return GL_FALSE;
1567 #endif
1568    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1569       return GL_FALSE;
1570
1571    return GL_TRUE;
1572 }
1573
1574
1575 /**
1576  * Check if the viewport/scissor size has not yet been initialized.
1577  * Initialize the size if the given width and height are non-zero.
1578  */
1579 void
1580 _mesa_check_init_viewport(struct gl_context *ctx, GLuint width, GLuint height)
1581 {
1582    if (!ctx->ViewportInitialized && width > 0 && height > 0) {
1583       unsigned i;
1584
1585       /* Note: set flag here, before calling _mesa_set_viewport(), to prevent
1586        * potential infinite recursion.
1587        */
1588       ctx->ViewportInitialized = GL_TRUE;
1589
1590       /* Note: ctx->Const.MaxViewports may not have been set by the driver
1591        * yet, so just initialize all of them.
1592        */
1593       for (i = 0; i < MAX_VIEWPORTS; i++) {
1594          _mesa_set_viewport(ctx, i, 0, 0, width, height);
1595          _mesa_set_scissor(ctx, i, 0, 0, width, height);
1596       }
1597    }
1598 }
1599
1600 static void
1601 handle_first_current(struct gl_context *ctx)
1602 {
1603    GLenum buffer;
1604    GLint bufferIndex;
1605
1606    if (ctx->Version == 0) {
1607       /* probably in the process of tearing down the context */
1608       return;
1609    }
1610
1611    ctx->Extensions.String = _mesa_make_extension_string(ctx);
1612
1613    check_context_limits(ctx);
1614
1615    /* According to GL_MESA_configless_context the default value of
1616     * glDrawBuffers depends on the config of the first surface it is bound to.
1617     * For GLES it is always GL_BACK which has a magic interpretation */
1618    if (!ctx->HasConfig && _mesa_is_desktop_gl(ctx)) {
1619       if (ctx->DrawBuffer != _mesa_get_incomplete_framebuffer()) {
1620          if (ctx->DrawBuffer->Visual.doubleBufferMode)
1621             buffer = GL_BACK;
1622          else
1623             buffer = GL_FRONT;
1624
1625          _mesa_drawbuffers(ctx, ctx->DrawBuffer, 1, &buffer,
1626                            NULL /* destMask */);
1627       }
1628
1629       if (ctx->ReadBuffer != _mesa_get_incomplete_framebuffer()) {
1630          if (ctx->ReadBuffer->Visual.doubleBufferMode) {
1631             buffer = GL_BACK;
1632             bufferIndex = BUFFER_BACK_LEFT;
1633          }
1634          else {
1635             buffer = GL_FRONT;
1636             bufferIndex = BUFFER_FRONT_LEFT;
1637          }
1638
1639          _mesa_readbuffer(ctx, ctx->ReadBuffer, buffer, bufferIndex);
1640       }
1641    }
1642
1643    /* We can use this to help debug user's problems.  Tell them to set
1644     * the MESA_INFO env variable before running their app.  Then the
1645     * first time each context is made current we'll print some useful
1646     * information.
1647     */
1648    if (getenv("MESA_INFO")) {
1649       _mesa_print_info(ctx);
1650    }
1651 }
1652
1653 /**
1654  * Bind the given context to the given drawBuffer and readBuffer and
1655  * make it the current context for the calling thread.
1656  * We'll render into the drawBuffer and read pixels from the
1657  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1658  *
1659  * We check that the context's and framebuffer's visuals are compatible
1660  * and return immediately if they're not.
1661  *
1662  * \param newCtx  the new GL context. If NULL then there will be no current GL
1663  *                context.
1664  * \param drawBuffer  the drawing framebuffer
1665  * \param readBuffer  the reading framebuffer
1666  */
1667 GLboolean
1668 _mesa_make_current( struct gl_context *newCtx,
1669                     struct gl_framebuffer *drawBuffer,
1670                     struct gl_framebuffer *readBuffer )
1671 {
1672    GET_CURRENT_CONTEXT(curCtx);
1673
1674    if (MESA_VERBOSE & VERBOSE_API)
1675       _mesa_debug(newCtx, "_mesa_make_current()\n");
1676
1677    /* Check that the context's and framebuffer's visuals are compatible.
1678     */
1679    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1680       if (!check_compatible(newCtx, drawBuffer)) {
1681          _mesa_warning(newCtx,
1682               "MakeCurrent: incompatible visuals for context and drawbuffer");
1683          return GL_FALSE;
1684       }
1685    }
1686    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1687       if (!check_compatible(newCtx, readBuffer)) {
1688          _mesa_warning(newCtx,
1689               "MakeCurrent: incompatible visuals for context and readbuffer");
1690          return GL_FALSE;
1691       }
1692    }
1693
1694    if (curCtx &&
1695        (curCtx->WinSysDrawBuffer || curCtx->WinSysReadBuffer) &&
1696        /* make sure this context is valid for flushing */
1697        curCtx != newCtx &&
1698        curCtx->Const.ContextReleaseBehavior ==
1699        GL_CONTEXT_RELEASE_BEHAVIOR_FLUSH)
1700       _mesa_flush(curCtx);
1701
1702    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1703    _glapi_set_context((void *) newCtx);
1704    assert(_mesa_get_current_context() == newCtx);
1705
1706    if (!newCtx) {
1707       _glapi_set_dispatch(NULL);  /* none current */
1708    }
1709    else {
1710       _glapi_set_dispatch(newCtx->CurrentDispatch);
1711
1712       if (drawBuffer && readBuffer) {
1713          assert(_mesa_is_winsys_fbo(drawBuffer));
1714          assert(_mesa_is_winsys_fbo(readBuffer));
1715          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1716          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1717
1718          /*
1719           * Only set the context's Draw/ReadBuffer fields if they're NULL
1720           * or not bound to a user-created FBO.
1721           */
1722          if (!newCtx->DrawBuffer || _mesa_is_winsys_fbo(newCtx->DrawBuffer)) {
1723             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1724             /* Update the FBO's list of drawbuffers/renderbuffers.
1725              * For winsys FBOs this comes from the GL state (which may have
1726              * changed since the last time this FBO was bound).
1727              */
1728             _mesa_update_draw_buffers(newCtx);
1729          }
1730          if (!newCtx->ReadBuffer || _mesa_is_winsys_fbo(newCtx->ReadBuffer)) {
1731             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1732          }
1733
1734          /* XXX only set this flag if we're really changing the draw/read
1735           * framebuffer bindings.
1736           */
1737          newCtx->NewState |= _NEW_BUFFERS;
1738
1739          if (drawBuffer) {
1740             _mesa_check_init_viewport(newCtx,
1741                                       drawBuffer->Width, drawBuffer->Height);
1742          }
1743       }
1744
1745       if (newCtx->FirstTimeCurrent) {
1746          handle_first_current(newCtx);
1747          newCtx->FirstTimeCurrent = GL_FALSE;
1748       }
1749    }
1750
1751    return GL_TRUE;
1752 }
1753
1754
1755 /**
1756  * Make context 'ctx' share the display lists, textures and programs
1757  * that are associated with 'ctxToShare'.
1758  * Any display lists, textures or programs associated with 'ctx' will
1759  * be deleted if nobody else is sharing them.
1760  */
1761 GLboolean
1762 _mesa_share_state(struct gl_context *ctx, struct gl_context *ctxToShare)
1763 {
1764    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1765       struct gl_shared_state *oldShared = NULL;
1766
1767       /* save ref to old state to prevent it from being deleted immediately */
1768       _mesa_reference_shared_state(ctx, &oldShared, ctx->Shared);
1769
1770       /* update ctx's Shared pointer */
1771       _mesa_reference_shared_state(ctx, &ctx->Shared, ctxToShare->Shared);
1772
1773       update_default_objects(ctx);
1774
1775       /* release the old shared state */
1776       _mesa_reference_shared_state(ctx, &oldShared, NULL);
1777
1778       return GL_TRUE;
1779    }
1780    else {
1781       return GL_FALSE;
1782    }
1783 }
1784
1785
1786
1787 /**
1788  * \return pointer to the current GL context for this thread.
1789  *
1790  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1791  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1792  * context.h.
1793  */
1794 struct gl_context *
1795 _mesa_get_current_context( void )
1796 {
1797    return (struct gl_context *) _glapi_get_context();
1798 }
1799
1800
1801 /**
1802  * Get context's current API dispatch table.
1803  *
1804  * It'll either be the immediate-mode execute dispatcher or the display list
1805  * compile dispatcher.
1806  *
1807  * \param ctx GL context.
1808  *
1809  * \return pointer to dispatch_table.
1810  *
1811  * Simply returns __struct gl_contextRec::CurrentDispatch.
1812  */
1813 struct _glapi_table *
1814 _mesa_get_dispatch(struct gl_context *ctx)
1815 {
1816    return ctx->CurrentDispatch;
1817 }
1818
1819 /*@}*/
1820
1821
1822 /**********************************************************************/
1823 /** \name Miscellaneous functions                                     */
1824 /**********************************************************************/
1825 /*@{*/
1826
1827 /**
1828  * Record an error.
1829  *
1830  * \param ctx GL context.
1831  * \param error error code.
1832  *
1833  * Records the given error code and call the driver's dd_function_table::Error
1834  * function if defined.
1835  *
1836  * \sa
1837  * This is called via _mesa_error().
1838  */
1839 void
1840 _mesa_record_error(struct gl_context *ctx, GLenum error)
1841 {
1842    if (!ctx)
1843       return;
1844
1845    if (ctx->ErrorValue == GL_NO_ERROR) {
1846       ctx->ErrorValue = error;
1847    }
1848 }
1849
1850
1851 /**
1852  * Flush commands and wait for completion.
1853  */
1854 void
1855 _mesa_finish(struct gl_context *ctx)
1856 {
1857    FLUSH_VERTICES( ctx, 0 );
1858    FLUSH_CURRENT( ctx, 0 );
1859    if (ctx->Driver.Finish) {
1860       ctx->Driver.Finish(ctx);
1861    }
1862 }
1863
1864
1865 /**
1866  * Flush commands.
1867  */
1868 void
1869 _mesa_flush(struct gl_context *ctx)
1870 {
1871    FLUSH_VERTICES( ctx, 0 );
1872    FLUSH_CURRENT( ctx, 0 );
1873    if (ctx->Driver.Flush) {
1874       ctx->Driver.Flush(ctx);
1875    }
1876 }
1877
1878
1879
1880 /**
1881  * Execute glFinish().
1882  *
1883  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1884  * dd_function_table::Finish driver callback, if not NULL.
1885  */
1886 void GLAPIENTRY
1887 _mesa_Finish(void)
1888 {
1889    GET_CURRENT_CONTEXT(ctx);
1890    ASSERT_OUTSIDE_BEGIN_END(ctx);
1891    _mesa_finish(ctx);
1892 }
1893
1894
1895 /**
1896  * Execute glFlush().
1897  *
1898  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1899  * dd_function_table::Flush driver callback, if not NULL.
1900  */
1901 void GLAPIENTRY
1902 _mesa_Flush(void)
1903 {
1904    GET_CURRENT_CONTEXT(ctx);
1905    ASSERT_OUTSIDE_BEGIN_END(ctx);
1906    _mesa_flush(ctx);
1907 }
1908
1909
1910 /*
1911  * ARB_blend_func_extended - ERRORS section
1912  * "The error INVALID_OPERATION is generated by Begin or any procedure that
1913  *  implicitly calls Begin if any draw buffer has a blend function requiring the
1914  *  second color input (SRC1_COLOR, ONE_MINUS_SRC1_COLOR, SRC1_ALPHA or
1915  *  ONE_MINUS_SRC1_ALPHA), and a framebuffer is bound that has more than
1916  *  the value of MAX_DUAL_SOURCE_DRAW_BUFFERS-1 active color attachements."
1917  */
1918 static GLboolean
1919 _mesa_check_blend_func_error(struct gl_context *ctx)
1920 {
1921    GLuint i;
1922    for (i = ctx->Const.MaxDualSourceDrawBuffers;
1923         i < ctx->DrawBuffer->_NumColorDrawBuffers;
1924         i++) {
1925       if (ctx->Color.Blend[i]._UsesDualSrc) {
1926          _mesa_error(ctx, GL_INVALID_OPERATION,
1927                      "dual source blend on illegal attachment");
1928          return GL_FALSE;
1929       }
1930    }
1931    return GL_TRUE;
1932 }
1933
1934
1935 /**
1936  * Prior to drawing anything with glBegin, glDrawArrays, etc. this function
1937  * is called to see if it's valid to render.  This involves checking that
1938  * the current shader is valid and the framebuffer is complete.
1939  * It also check the current pipeline object is valid if any.
1940  * If an error is detected it'll be recorded here.
1941  * \return GL_TRUE if OK to render, GL_FALSE if not
1942  */
1943 GLboolean
1944 _mesa_valid_to_render(struct gl_context *ctx, const char *where)
1945 {
1946    /* This depends on having up to date derived state (shaders) */
1947    if (ctx->NewState)
1948       _mesa_update_state(ctx);
1949
1950    if (ctx->API == API_OPENGL_COMPAT) {
1951       /* Any shader stages that are not supplied by the GLSL shader and have
1952        * assembly shaders enabled must now be validated.
1953        */
1954       if (!ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX]
1955           && ctx->VertexProgram.Enabled && !ctx->VertexProgram._Enabled) {
1956          _mesa_error(ctx, GL_INVALID_OPERATION,
1957                      "%s(vertex program not valid)", where);
1958          return GL_FALSE;
1959       }
1960
1961       if (!ctx->_Shader->CurrentProgram[MESA_SHADER_FRAGMENT]) {
1962          if (ctx->FragmentProgram.Enabled && !ctx->FragmentProgram._Enabled) {
1963             _mesa_error(ctx, GL_INVALID_OPERATION,
1964                         "%s(fragment program not valid)", where);
1965             return GL_FALSE;
1966          }
1967
1968          /* If drawing to integer-valued color buffers, there must be an
1969           * active fragment shader (GL_EXT_texture_integer).
1970           */
1971          if (ctx->DrawBuffer && ctx->DrawBuffer->_IntegerColor) {
1972             _mesa_error(ctx, GL_INVALID_OPERATION,
1973                         "%s(integer format but no fragment shader)", where);
1974             return GL_FALSE;
1975          }
1976       }
1977    }
1978
1979    /* A pipeline object is bound */
1980    if (ctx->_Shader->Name && !ctx->_Shader->Validated) {
1981       if (!_mesa_validate_program_pipeline(ctx, ctx->_Shader)) {
1982          _mesa_error(ctx, GL_INVALID_OPERATION,
1983                      "glValidateProgramPipeline failed to validate the "
1984                      "pipeline");
1985          return GL_FALSE;
1986       }
1987    }
1988
1989    /* If a program is active and SSO not in use, check if validation of
1990     * samplers succeeded for the active program. */
1991    if (ctx->_Shader->ActiveProgram && ctx->_Shader != ctx->Pipeline.Current) {
1992       char errMsg[100];
1993       if (!_mesa_sampler_uniforms_are_valid(ctx->_Shader->ActiveProgram,
1994                                             errMsg, 100)) {
1995          _mesa_error(ctx, GL_INVALID_OPERATION, "%s", errMsg);
1996          return GL_FALSE;
1997       }
1998    }
1999
2000    if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
2001       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
2002                   "%s(incomplete framebuffer)", where);
2003       return GL_FALSE;
2004    }
2005
2006    if (_mesa_check_blend_func_error(ctx) == GL_FALSE) {
2007       return GL_FALSE;
2008    }
2009
2010 #ifdef DEBUG
2011    if (ctx->_Shader->Flags & GLSL_LOG) {
2012       struct gl_shader_program **shProg = ctx->_Shader->CurrentProgram;
2013       gl_shader_stage i;
2014
2015       for (i = 0; i < MESA_SHADER_STAGES; i++) {
2016          if (shProg[i] == NULL || shProg[i]->_Used
2017              || shProg[i]->_LinkedShaders[i] == NULL)
2018             continue;
2019
2020          /* This is the first time this shader is being used.
2021           * Append shader's constants/uniforms to log file.
2022           *
2023           * Only log data for the program target that matches the shader
2024           * target.  It's possible to have a program bound to the vertex
2025           * shader target that also supplied a fragment shader.  If that
2026           * program isn't also bound to the fragment shader target we don't
2027           * want to log its fragment data.
2028           */
2029          _mesa_append_uniforms_to_file(shProg[i]->_LinkedShaders[i]);
2030       }
2031
2032       for (i = 0; i < MESA_SHADER_STAGES; i++) {
2033          if (shProg[i] != NULL)
2034             shProg[i]->_Used = GL_TRUE;
2035       }
2036    }
2037 #endif
2038
2039    return GL_TRUE;
2040 }
2041
2042
2043 /*@}*/