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 #if FEATURE_accum
  83 #include "accum.h"
  84 #endif
  85 #include "api_exec.h"
  86 #include "arrayobj.h"
  87 #if FEATURE_attrib_stack
  88 #include "attrib.h"
  89 #endif
  90 #include "blend.h"
  91 #include "buffers.h"
  92 #include "bufferobj.h"
  93 #if FEATURE_colortable
  94 #include "colortab.h"
  95 #endif
  96 #include "context.h"
  97 #include "cpuinfo.h"
  98 #include "debug.h"
  99 #include "depth.h"
 100 #if FEATURE_dlist
 101 #include "dlist.h"
 102 #endif
 103 #if FEATURE_evaluators
 104 #include "eval.h"
 105 #endif
 106 #include "enums.h"
 107 #include "extensions.h"
 108 #include "fbobject.h"
 109 #if FEATURE_feedback
 110 #include "feedback.h"
 111 #endif
 112 #include "fog.h"
 113 #include "framebuffer.h"
 114 #include "get.h"
 115 #if FEATURE_histogram
 116 #include "histogram.h"
 117 #endif
 118 #include "hint.h"
 119 #include "hash.h"
 120 #include "light.h"
 121 #include "lines.h"
 122 #include "macros.h"
 123 #include "matrix.h"
 124 #include "multisample.h"
 125 #include "pixel.h"
 126 #include "pixelstore.h"
 127 #include "points.h"
 128 #include "polygon.h"
 129 #if FEATURE_ARB_occlusion_query
 130 #include "queryobj.h"
 131 #endif
 132 #if FEATURE_drawpix
 133 #include "rastpos.h"
 134 #endif
 135 #include "scissor.h"
 136 #include "shared.h"
 137 #include "simple_list.h"
 138 #include "state.h"
 139 #include "stencil.h"
 140 #include "texcompress.h"
 141 #include "teximage.h"
 142 #include "texobj.h"
 143 #include "texstate.h"
 144 #include "mtypes.h"
 145 #include "varray.h"
 146 #include "version.h"
 147 #include "viewport.h"
 148 #include "vtxfmt.h"
 149 #include "glapi/glthread.h"
 150 #include "glapi/glapioffsets.h"
 151 #include "glapi/glapitable.h"
 152 #include "shader/program.h"
 153 #include "shader/shader_api.h"
 154 #if FEATURE_ATI_fragment_shader
 155 #include "shader/atifragshader.h"
 156 #endif
 157 #if _HAVE_FULL_GL
 158 #include "math/m_matrix.h"
 159 #endif
 160
 161 #ifdef USE_SPARC_ASM
 162 #include "sparc/sparc.h"
 163 #endif
 164
 165 #ifndef MESA_VERBOSE
 166 int MESA_VERBOSE = 0;
 167 #endif
 168
 169 #ifndef MESA_DEBUG_FLAGS
 170 int MESA_DEBUG_FLAGS = 0;
 171 #endif
 172
 173
 174 /* ubyte -> float conversion */
 175 GLfloat _mesa_ubyte_to_float_color_tab[256];
 176
 177
 178
 179 /**
 180  * Swap buffers notification callback.
 181  *
 182  * \param gc GL context.
 183  *
 184  * Called by window system just before swapping buffers.
 185  * We have to finish any pending rendering.
 186  */
 187 void
 188 _mesa_notifySwapBuffers(__GLcontext *ctx)
 189 {
 190    FLUSH_VERTICES( ctx, 0 );
 191    if (ctx->Driver.Flush) {
 192       ctx->Driver.Flush(ctx);
 193    }
 194 }
 195
 196
 197 /**********************************************************************/
 198 /** \name GL Visual allocation/destruction                            */
 199 /**********************************************************************/
 200 /*@{*/
 201
 202 /**
 203  * Allocates a GLvisual structure and initializes it via
 204  * _mesa_initialize_visual().
 205  *
 206  * \param rgbFlag GL_TRUE for RGB(A) mode, GL_FALSE for Color Index mode.
 207  * \param dbFlag double buffering
 208  * \param stereoFlag stereo buffer
 209  * \param depthBits requested bits per depth buffer value. Any value in [0, 32]
 210  * is acceptable but the actual depth type will be GLushort or GLuint as
 211  * needed.
 212  * \param stencilBits requested minimum bits per stencil buffer value
 213  * \param accumRedBits, accumGreenBits, accumBlueBits, accumAlphaBits number of bits per color component in accum buffer.
 214  * \param indexBits number of bits per pixel if \p rgbFlag is GL_FALSE
 215  * \param redBits number of bits per color component in frame buffer for RGB(A)
 216  * mode.  We always use 8 in core Mesa though.
 217  * \param greenBits same as above.
 218  * \param blueBits same as above.
 219  * \param alphaBits same as above.
 220  * \param numSamples not really used.
 221  *
 222  * \return pointer to new GLvisual or NULL if requested parameters can't be
 223  * met.
 224  *
 225  * \note Need to add params for level and numAuxBuffers (at least)
 226  */
 227 GLvisual *
 228 _mesa_create_visual( GLboolean rgbFlag,
 229                      GLboolean dbFlag,
 230                      GLboolean stereoFlag,
 231                      GLint redBits,
 232                      GLint greenBits,
 233                      GLint blueBits,
 234                      GLint alphaBits,
 235                      GLint indexBits,
 236                      GLint depthBits,
 237                      GLint stencilBits,
 238                      GLint accumRedBits,
 239                      GLint accumGreenBits,
 240                      GLint accumBlueBits,
 241                      GLint accumAlphaBits,
 242                      GLint numSamples )
 243 {
 244    GLvisual *vis = (GLvisual *) _mesa_calloc(sizeof(GLvisual));
 245    if (vis) {
 246       if (!_mesa_initialize_visual(vis, rgbFlag, dbFlag, stereoFlag,
 247                                    redBits, greenBits, blueBits, alphaBits,
 248                                    indexBits, depthBits, stencilBits,
 249                                    accumRedBits, accumGreenBits,
 250                                    accumBlueBits, accumAlphaBits,
 251                                    numSamples)) {
 252          _mesa_free(vis);
 253          return NULL;
 254       }
 255    }
 256    return vis;
 257 }
 258
 259 /**
 260  * Makes some sanity checks and fills in the fields of the
 261  * GLvisual object with the given parameters.  If the caller needs
 262  * to set additional fields, he should just probably init the whole GLvisual
 263  * object himself.
 264  * \return GL_TRUE on success, or GL_FALSE on failure.
 265  *
 266  * \sa _mesa_create_visual() above for the parameter description.
 267  */
 268 GLboolean
 269 _mesa_initialize_visual( GLvisual *vis,
 270                          GLboolean rgbFlag,
 271                          GLboolean dbFlag,
 272                          GLboolean stereoFlag,
 273                          GLint redBits,
 274                          GLint greenBits,
 275                          GLint blueBits,
 276                          GLint alphaBits,
 277                          GLint indexBits,
 278                          GLint depthBits,
 279                          GLint stencilBits,
 280                          GLint accumRedBits,
 281                          GLint accumGreenBits,
 282                          GLint accumBlueBits,
 283                          GLint accumAlphaBits,
 284                          GLint numSamples )
 285 {
 286    assert(vis);
 287
 288    if (depthBits < 0 || depthBits > 32) {
 289       return GL_FALSE;
 290    }
 291    if (stencilBits < 0 || stencilBits > STENCIL_BITS) {
 292       return GL_FALSE;
 293    }
 294    assert(accumRedBits >= 0);
 295    assert(accumGreenBits >= 0);
 296    assert(accumBlueBits >= 0);
 297    assert(accumAlphaBits >= 0);
 298
 299    vis->rgbMode          = rgbFlag;
 300    vis->doubleBufferMode = dbFlag;
 301    vis->stereoMode       = stereoFlag;
 302
 303    vis->redBits          = redBits;
 304    vis->greenBits        = greenBits;
 305    vis->blueBits         = blueBits;
 306    vis->alphaBits        = alphaBits;
 307    vis->rgbBits          = redBits + greenBits + blueBits;
 308
 309    vis->indexBits      = indexBits;
 310    vis->depthBits      = depthBits;
 311    vis->stencilBits    = stencilBits;
 312
 313    vis->accumRedBits   = accumRedBits;
 314    vis->accumGreenBits = accumGreenBits;
 315    vis->accumBlueBits  = accumBlueBits;
 316    vis->accumAlphaBits = accumAlphaBits;
 317
 318    vis->haveAccumBuffer   = accumRedBits > 0;
 319    vis->haveDepthBuffer   = depthBits > 0;
 320    vis->haveStencilBuffer = stencilBits > 0;
 321
 322    vis->numAuxBuffers = 0;
 323    vis->level = 0;
 324    vis->pixmapMode = 0;
 325    vis->sampleBuffers = numSamples > 0 ? 1 : 0;
 326    vis->samples = numSamples;
 327
 328    return GL_TRUE;
 329 }
 330
 331
 332 /**
 333  * Destroy a visual and free its memory.
 334  *
 335  * \param vis visual.
 336  *
 337  * Frees the visual structure.
 338  */
 339 void
 340 _mesa_destroy_visual( GLvisual *vis )
 341 {
 342    _mesa_free(vis);
 343 }
 344
 345 /*@}*/
 346
 347
 348 /**********************************************************************/
 349 /** \name Context allocation, initialization, destroying
 350  *
 351  * The purpose of the most initialization functions here is to provide the
 352  * default state values according to the OpenGL specification.
 353  */
 354 /**********************************************************************/
 355 /*@{*/
 356
 357
 358 /**
 359  * This is lame.  gdb only seems to recognize enum types that are
 360  * actually used somewhere.  We want to be able to print/use enum
 361  * values such as TEXTURE_2D_INDEX in gdb.  But we don't actually use
 362  * the gl_texture_index type anywhere.  Thus, this lame function.
 363  */
 364 static void
 365 dummy_enum_func(void)
 366 {
 367    gl_buffer_index bi;
 368    gl_colortable_index ci;
 369    gl_face_index fi;
 370    gl_frag_attrib fa;
 371    gl_frag_result fr;
 372    gl_texture_index ti;
 373    gl_vert_attrib va;
 374    gl_vert_result vr;
 375
 376    (void) bi;
 377    (void) ci;
 378    (void) fi;
 379    (void) fa;
 380    (void) fr;
 381    (void) ti;
 382    (void) va;
 383    (void) vr;
 384 }
 385
 386
 387 /**
 388  * One-time initialization mutex lock.
 389  *
 390  * \sa Used by one_time_init().
 391  */
 392 _glthread_DECLARE_STATIC_MUTEX(OneTimeLock);
 393
 394 /**
 395  * Calls all the various one-time-init functions in Mesa.
 396  *
 397  * While holding a global mutex lock, calls several initialization functions,
 398  * and sets the glapi callbacks if the \c MESA_DEBUG environment variable is
 399  * defined.
 400  *
 401  * \sa _math_init().
 402  */
 403 static void
 404 one_time_init( GLcontext *ctx )
 405 {
 406    static GLboolean alreadyCalled = GL_FALSE;
 407    (void) ctx;
 408    _glthread_LOCK_MUTEX(OneTimeLock);
 409    if (!alreadyCalled) {
 410       GLuint i;
 411
 412       /* do some implementation tests */
 413       assert( sizeof(GLbyte) == 1 );
 414       assert( sizeof(GLubyte) == 1 );
 415       assert( sizeof(GLshort) == 2 );
 416       assert( sizeof(GLushort) == 2 );
 417       assert( sizeof(GLint) == 4 );
 418       assert( sizeof(GLuint) == 4 );
 419
 420       _mesa_get_cpu_features();
 421
 422       _mesa_init_sqrt_table();
 423
 424       for (i = 0; i < 256; i++) {
 425          _mesa_ubyte_to_float_color_tab[i] = (float) i / 255.0F;
 426       }
 427
 428       if (_mesa_getenv("MESA_DEBUG")) {
 429          _glapi_noop_enable_warnings(GL_TRUE);
 430          _glapi_set_warning_func( (_glapi_warning_func) _mesa_warning );
 431       }
 432       else {
 433          _glapi_noop_enable_warnings(GL_FALSE);
 434       }
 435
 436 #if defined(DEBUG) && defined(__DATE__) && defined(__TIME__)
 437       _mesa_debug(ctx, "Mesa %s DEBUG build %s %s\n",
 438                   MESA_VERSION_STRING, __DATE__, __TIME__);
 439 #endif
 440
 441       alreadyCalled = GL_TRUE;
 442    }
 443    _glthread_UNLOCK_MUTEX(OneTimeLock);
 444
 445    dummy_enum_func();
 446 }
 447
 448
 449 /**
 450  * Initialize fields of gl_current_attrib (aka ctx->Current.*)
 451  */
 452 static void
 453 _mesa_init_current(GLcontext *ctx)
 454 {
 455    GLuint i;
 456
 457    /* Init all to (0,0,0,1) */
 458    for (i = 0; i < VERT_ATTRIB_MAX; i++) {
 459       ASSIGN_4V( ctx->Current.Attrib[i], 0.0, 0.0, 0.0, 1.0 );
 460    }
 461
 462    /* redo special cases: */
 463    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_WEIGHT], 1.0, 0.0, 0.0, 0.0 );
 464    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_NORMAL], 0.0, 0.0, 1.0, 1.0 );
 465    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR0], 1.0, 1.0, 1.0, 1.0 );
 466    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR1], 0.0, 0.0, 0.0, 1.0 );
 467    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_COLOR_INDEX], 1.0, 0.0, 0.0, 1.0 );
 468    ASSIGN_4V( ctx->Current.Attrib[VERT_ATTRIB_EDGEFLAG], 1.0, 0.0, 0.0, 1.0 );
 469 }
 470
 471
 472 /**
 473  * Init vertex/fragment program limits.
 474  * Important: drivers should override these with actual limits.
 475  */
 476 static void
 477 init_program_limits(GLenum type, struct gl_program_constants *prog)
 478 {
 479    prog->MaxInstructions = MAX_PROGRAM_INSTRUCTIONS;
 480    prog->MaxAluInstructions = MAX_PROGRAM_INSTRUCTIONS;
 481    prog->MaxTexInstructions = MAX_PROGRAM_INSTRUCTIONS;
 482    prog->MaxTexIndirections = MAX_PROGRAM_INSTRUCTIONS;
 483    prog->MaxTemps = MAX_PROGRAM_TEMPS;
 484    prog->MaxEnvParams = MAX_PROGRAM_ENV_PARAMS;
 485    prog->MaxLocalParams = MAX_PROGRAM_LOCAL_PARAMS;
 486    prog->MaxUniformComponents = 4 * MAX_UNIFORMS;
 487
 488    if (type == GL_VERTEX_PROGRAM_ARB) {
 489       prog->MaxParameters = MAX_NV_VERTEX_PROGRAM_PARAMS;
 490       prog->MaxAttribs = MAX_NV_VERTEX_PROGRAM_INPUTS;
 491       prog->MaxAddressRegs = MAX_VERTEX_PROGRAM_ADDRESS_REGS;
 492    }
 493    else {
 494       prog->MaxParameters = MAX_NV_FRAGMENT_PROGRAM_PARAMS;
 495       prog->MaxAttribs = MAX_NV_FRAGMENT_PROGRAM_INPUTS;
 496       prog->MaxAddressRegs = MAX_FRAGMENT_PROGRAM_ADDRESS_REGS;
 497    }
 498
 499    /* copy the above limits to init native limits */
 500    prog->MaxNativeInstructions = prog->MaxInstructions;
 501    prog->MaxNativeAluInstructions = prog->MaxAluInstructions;
 502    prog->MaxNativeTexInstructions = prog->MaxTexInstructions;
 503    prog->MaxNativeTexIndirections = prog->MaxTexIndirections;
 504    prog->MaxNativeAttribs = prog->MaxAttribs;
 505    prog->MaxNativeTemps = prog->MaxTemps;
 506    prog->MaxNativeAddressRegs = prog->MaxAddressRegs;
 507    prog->MaxNativeParameters = prog->MaxParameters;
 508 }
 509
 510
 511 /**
 512  * Initialize fields of gl_constants (aka ctx->Const.*).
 513  * Use defaults from config.h.  The device drivers will often override
 514  * some of these values (such as number of texture units).
 515  */
 516 static void
 517 _mesa_init_constants(GLcontext *ctx)
 518 {
 519    assert(ctx);
 520
 521    assert(MAX_TEXTURE_LEVELS >= MAX_3D_TEXTURE_LEVELS);
 522    assert(MAX_TEXTURE_LEVELS >= MAX_CUBE_TEXTURE_LEVELS);
 523
 524    /* Max texture size should be <= max viewport size (render to texture) */
 525    assert((1 << (MAX_TEXTURE_LEVELS - 1)) <= MAX_WIDTH);
 526
 527    /* Constants, may be overriden (usually only reduced) by device drivers */
 528    ctx->Const.MaxTextureLevels = MAX_TEXTURE_LEVELS;
 529    ctx->Const.Max3DTextureLevels = MAX_3D_TEXTURE_LEVELS;
 530    ctx->Const.MaxCubeTextureLevels = MAX_CUBE_TEXTURE_LEVELS;
 531    ctx->Const.MaxTextureRectSize = MAX_TEXTURE_RECT_SIZE;
 532    ctx->Const.MaxArrayTextureLayers = MAX_ARRAY_TEXTURE_LAYERS;
 533    ctx->Const.MaxTextureCoordUnits = MAX_TEXTURE_COORD_UNITS;
 534    ctx->Const.MaxTextureImageUnits = MAX_TEXTURE_IMAGE_UNITS;
 535    ctx->Const.MaxTextureUnits = MIN2(ctx->Const.MaxTextureCoordUnits,
 536                                      ctx->Const.MaxTextureImageUnits);
 537    ctx->Const.MaxTextureMaxAnisotropy = MAX_TEXTURE_MAX_ANISOTROPY;
 538    ctx->Const.MaxTextureLodBias = MAX_TEXTURE_LOD_BIAS;
 539    ctx->Const.MaxArrayLockSize = MAX_ARRAY_LOCK_SIZE;
 540    ctx->Const.SubPixelBits = SUB_PIXEL_BITS;
 541    ctx->Const.MinPointSize = MIN_POINT_SIZE;
 542    ctx->Const.MaxPointSize = MAX_POINT_SIZE;
 543    ctx->Const.MinPointSizeAA = MIN_POINT_SIZE;
 544    ctx->Const.MaxPointSizeAA = MAX_POINT_SIZE;
 545    ctx->Const.PointSizeGranularity = (GLfloat) POINT_SIZE_GRANULARITY;
 546    ctx->Const.MinLineWidth = MIN_LINE_WIDTH;
 547    ctx->Const.MaxLineWidth = MAX_LINE_WIDTH;
 548    ctx->Const.MinLineWidthAA = MIN_LINE_WIDTH;
 549    ctx->Const.MaxLineWidthAA = MAX_LINE_WIDTH;
 550    ctx->Const.LineWidthGranularity = (GLfloat) LINE_WIDTH_GRANULARITY;
 551    ctx->Const.MaxColorTableSize = MAX_COLOR_TABLE_SIZE;
 552    ctx->Const.MaxConvolutionWidth = MAX_CONVOLUTION_WIDTH;
 553    ctx->Const.MaxConvolutionHeight = MAX_CONVOLUTION_HEIGHT;
 554    ctx->Const.MaxClipPlanes = MAX_CLIP_PLANES;
 555    ctx->Const.MaxLights = MAX_LIGHTS;
 556    ctx->Const.MaxShininess = 128.0;
 557    ctx->Const.MaxSpotExponent = 128.0;
 558    ctx->Const.MaxViewportWidth = MAX_WIDTH;
 559    ctx->Const.MaxViewportHeight = MAX_HEIGHT;
 560 #if FEATURE_ARB_vertex_program
 561    init_program_limits(GL_VERTEX_PROGRAM_ARB, &ctx->Const.VertexProgram);
 562 #endif
 563 #if FEATURE_ARB_fragment_program
 564    init_program_limits(GL_FRAGMENT_PROGRAM_ARB, &ctx->Const.FragmentProgram);
 565 #endif
 566    ctx->Const.MaxProgramMatrices = MAX_PROGRAM_MATRICES;
 567    ctx->Const.MaxProgramMatrixStackDepth = MAX_PROGRAM_MATRIX_STACK_DEPTH;
 568
 569    /* CheckArrayBounds is overriden by drivers/x11 for X server */
 570    ctx->Const.CheckArrayBounds = GL_FALSE;
 571
 572    /* GL_ARB_draw_buffers */
 573    ctx->Const.MaxDrawBuffers = MAX_DRAW_BUFFERS;
 574
 575    /* GL_OES_read_format */
 576    ctx->Const.ColorReadFormat = GL_RGBA;
 577    ctx->Const.ColorReadType = GL_UNSIGNED_BYTE;
 578
 579 #if FEATURE_EXT_framebuffer_object
 580    ctx->Const.MaxColorAttachments = MAX_COLOR_ATTACHMENTS;
 581    ctx->Const.MaxRenderbufferSize = MAX_WIDTH;
 582 #endif
 583
 584 #if FEATURE_ARB_vertex_shader
 585    ctx->Const.MaxVertexTextureImageUnits = MAX_VERTEX_TEXTURE_IMAGE_UNITS;
 586    ctx->Const.MaxVarying = MAX_VARYING;
 587 #endif
 588
 589    /* GL_ARB_framebuffer_object */
 590    ctx->Const.MaxSamples = 0;
 591
 592    /* sanity checks */
 593    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
 594                                              ctx->Const.MaxTextureCoordUnits));
 595    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 596    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 597
 598    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 599    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 600    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
 601    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
 602 }
 603
 604
 605 /**
 606  * Do some sanity checks on the limits/constants for the given context.
 607  * Only called the first time a context is bound.
 608  */
 609 static void
 610 check_context_limits(GLcontext *ctx)
 611 {
 612    /* Many context limits/constants are limited by the size of
 613     * internal arrays.
 614     */
 615    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 616    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 617    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 618    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 619
 620    /* number of coord units cannot be greater than number of image units */
 621    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.MaxTextureImageUnits);
 622
 623    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 624    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 625    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 626    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 627
 628    /* make sure largest texture image is <= MAX_WIDTH in size */
 629    assert((1 << (ctx->Const.MaxTextureLevels - 1)) <= MAX_WIDTH);
 630    assert((1 << (ctx->Const.MaxCubeTextureLevels - 1)) <= MAX_WIDTH);
 631    assert((1 << (ctx->Const.Max3DTextureLevels - 1)) <= MAX_WIDTH);
 632
 633    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
 634    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
 635
 636    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 637
 638    /* XXX probably add more tests */
 639 }
 640
 641
 642 /**
 643  * Initialize the attribute groups in a GL context.
 644  *
 645  * \param ctx GL context.
 646  *
 647  * Initializes all the attributes, calling the respective <tt>init*</tt>
 648  * functions for the more complex data structures.
 649  */
 650 static GLboolean
 651 init_attrib_groups(GLcontext *ctx)
 652 {
 653    assert(ctx);
 654
 655    /* Constants */
 656    _mesa_init_constants( ctx );
 657
 658    /* Extensions */
 659    _mesa_init_extensions( ctx );
 660
 661    /* Attribute Groups */
 662 #if FEATURE_accum
 663    _mesa_init_accum( ctx );
 664 #endif
 665 #if FEATURE_attrib_stack
 666    _mesa_init_attrib( ctx );
 667 #endif
 668    _mesa_init_buffer_objects( ctx );
 669    _mesa_init_color( ctx );
 670 #if FEATURE_colortable
 671    _mesa_init_colortables( ctx );
 672 #endif
 673    _mesa_init_current( ctx );
 674    _mesa_init_depth( ctx );
 675    _mesa_init_debug( ctx );
 676 #if FEATURE_dlist
 677    _mesa_init_display_list( ctx );
 678 #endif
 679 #if FEATURE_evaluators
 680    _mesa_init_eval( ctx );
 681 #endif
 682    _mesa_init_fbobjects( ctx );
 683 #if FEATURE_feedback
 684    _mesa_init_feedback( ctx );
 685 #else
 686    ctx->RenderMode = GL_RENDER;
 687 #endif
 688    _mesa_init_fog( ctx );
 689 #if FEATURE_histogram
 690    _mesa_init_histogram( ctx );
 691 #endif
 692    _mesa_init_hint( ctx );
 693    _mesa_init_line( ctx );
 694    _mesa_init_lighting( ctx );
 695    _mesa_init_matrix( ctx );
 696    _mesa_init_multisample( ctx );
 697    _mesa_init_pixel( ctx );
 698    _mesa_init_pixelstore( ctx );
 699    _mesa_init_point( ctx );
 700    _mesa_init_polygon( ctx );
 701    _mesa_init_program( ctx );
 702 #if FEATURE_ARB_occlusion_query
 703    _mesa_init_query( ctx );
 704 #endif
 705 #if FEATURE_drawpix
 706    _mesa_init_rastpos( ctx );
 707 #endif
 708    _mesa_init_scissor( ctx );
 709    _mesa_init_shader_state( ctx );
 710    _mesa_init_stencil( ctx );
 711    _mesa_init_transform( ctx );
 712    _mesa_init_varray( ctx );
 713    _mesa_init_viewport( ctx );
 714
 715    if (!_mesa_init_texture( ctx ))
 716       return GL_FALSE;
 717
 718 #if FEATURE_texture_s3tc
 719    _mesa_init_texture_s3tc( ctx );
 720 #endif
 721 #if FEATURE_texture_fxt1
 722    _mesa_init_texture_fxt1( ctx );
 723 #endif
 724
 725    /* Miscellaneous */
 726    ctx->NewState = _NEW_ALL;
 727    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
 728    ctx->varying_vp_inputs = ~0;
 729
 730    return GL_TRUE;
 731 }
 732
 733
 734 /**
 735  * Update default objects in a GL context with respect to shared state.
 736  *
 737  * \param ctx GL context.
 738  *
 739  * Removes references to old default objects, (texture objects, program
 740  * objects, etc.) and changes to reference those from the current shared
 741  * state.
 742  */
 743 static GLboolean
 744 update_default_objects(GLcontext *ctx)
 745 {
 746    assert(ctx);
 747
 748    _mesa_update_default_objects_program(ctx);
 749    _mesa_update_default_objects_texture(ctx);
 750    _mesa_update_default_objects_buffer_objects(ctx);
 751
 752    return GL_TRUE;
 753 }
 754
 755
 756 /**
 757  * This is the default function we plug into all dispatch table slots
 758  * This helps prevents a segfault when someone calls a GL function without
 759  * first checking if the extension's supported.
 760  */
 761 static int
 762 generic_nop(void)
 763 {
 764    _mesa_warning(NULL, "User called no-op dispatch function (an unsupported extension function?)");
 765    return 0;
 766 }
 767
 768
 769 /**
 770  * Allocate and initialize a new dispatch table.
 771  */
 772 static struct _glapi_table *
 773 alloc_dispatch_table(void)
 774 {
 775    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
 776     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
 777     * Mesa we do this to accomodate different versions of libGL and various
 778     * DRI drivers.
 779     */
 780    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
 781                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
 782    struct _glapi_table *table =
 783       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
 784    if (table) {
 785       _glapi_proc *entry = (_glapi_proc *) table;
 786       GLint i;
 787       for (i = 0; i < numEntries; i++) {
 788          entry[i] = (_glapi_proc) generic_nop;
 789       }
 790    }
 791    return table;
 792 }
 793
 794
 795 /**
 796  * Initialize a GLcontext struct (rendering context).
 797  *
 798  * This includes allocating all the other structs and arrays which hang off of
 799  * the context by pointers.
 800  * Note that the driver needs to pass in its dd_function_table here since
 801  * we need to at least call driverFunctions->NewTextureObject to create the
 802  * default texture objects.
 803  *
 804  * Called by _mesa_create_context().
 805  *
 806  * Performs the imports and exports callback tables initialization, and
 807  * miscellaneous one-time initializations. If no shared context is supplied one
 808  * is allocated, and increase its reference count.  Setups the GL API dispatch
 809  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
 810  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
 811  * for debug flags.
 812  *
 813  * \param ctx the context to initialize
 814  * \param visual describes the visual attributes for this context
 815  * \param share_list points to context to share textures, display lists,
 816  *        etc with, or NULL
 817  * \param driverFunctions table of device driver functions for this context
 818  *        to use
 819  * \param driverContext pointer to driver-specific context data
 820  */
 821 GLboolean
 822 _mesa_initialize_context(GLcontext *ctx,
 823                          const GLvisual *visual,
 824                          GLcontext *share_list,
 825                          const struct dd_function_table *driverFunctions,
 826                          void *driverContext)
 827 {
 828    struct gl_shared_state *shared;
 829
 830    /*ASSERT(driverContext);*/
 831    assert(driverFunctions->NewTextureObject);
 832    assert(driverFunctions->FreeTexImageData);
 833
 834    /* misc one-time initializations */
 835    one_time_init(ctx);
 836
 837    ctx->Visual = *visual;
 838    ctx->DrawBuffer = NULL;
 839    ctx->ReadBuffer = NULL;
 840    ctx->WinSysDrawBuffer = NULL;
 841    ctx->WinSysReadBuffer = NULL;
 842
 843    /* Plug in driver functions and context pointer here.
 844     * This is important because when we call alloc_shared_state() below
 845     * we'll call ctx->Driver.NewTextureObject() to create the default
 846     * textures.
 847     */
 848    ctx->Driver = *driverFunctions;
 849    ctx->DriverCtx = driverContext;
 850
 851    if (share_list) {
 852       /* share state with another context */
 853       shared = share_list->Shared;
 854    }
 855    else {
 856       /* allocate new, unshared state */
 857       shared = _mesa_alloc_shared_state(ctx);
 858       if (!shared)
 859          return GL_FALSE;
 860    }
 861
 862    _glthread_LOCK_MUTEX(shared->Mutex);
 863    ctx->Shared = shared;
 864    shared->RefCount++;
 865    _glthread_UNLOCK_MUTEX(shared->Mutex);
 866
 867    if (!init_attrib_groups( ctx )) {
 868       _mesa_free_shared_state(ctx, ctx->Shared);
 869       return GL_FALSE;
 870    }
 871
 872    /* setup the API dispatch tables */
 873    ctx->Exec = alloc_dispatch_table();
 874    ctx->Save = alloc_dispatch_table();
 875    if (!ctx->Exec || !ctx->Save) {
 876       _mesa_free_shared_state(ctx, ctx->Shared);
 877       if (ctx->Exec)
 878          _mesa_free(ctx->Exec);
 879    }
 880 #if FEATURE_dispatch
 881    _mesa_init_exec_table(ctx->Exec);
 882 #endif
 883    ctx->CurrentDispatch = ctx->Exec;
 884 #if FEATURE_dlist
 885    _mesa_init_dlist_table(ctx->Save);
 886    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
 887 #endif
 888    /* Neutral tnl module stuff */
 889    _mesa_init_exec_vtxfmt( ctx );
 890    ctx->TnlModule.Current = NULL;
 891    ctx->TnlModule.SwapCount = 0;
 892
 893    ctx->FragmentProgram._MaintainTexEnvProgram
 894       = (_mesa_getenv("MESA_TEX_PROG") != NULL);
 895
 896    ctx->VertexProgram._MaintainTnlProgram
 897       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
 898    if (ctx->VertexProgram._MaintainTnlProgram) {
 899       /* this is required... */
 900       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
 901    }
 902
 903 #ifdef FEATURE_extra_context_init
 904    _mesa_initialize_context_extra(ctx);
 905 #endif
 906
 907    ctx->FirstTimeCurrent = GL_TRUE;
 908
 909    return GL_TRUE;
 910 }
 911
 912
 913 /**
 914  * Allocate and initialize a GLcontext structure.
 915  * Note that the driver needs to pass in its dd_function_table here since
 916  * we need to at least call driverFunctions->NewTextureObject to initialize
 917  * the rendering context.
 918  *
 919  * \param visual a GLvisual pointer (we copy the struct contents)
 920  * \param share_list another context to share display lists with or NULL
 921  * \param driverFunctions points to the dd_function_table into which the
 922  *        driver has plugged in all its special functions.
 923  * \param driverCtx points to the device driver's private context state
 924  *
 925  * \return pointer to a new __GLcontextRec or NULL if error.
 926  */
 927 GLcontext *
 928 _mesa_create_context(const GLvisual *visual,
 929                      GLcontext *share_list,
 930                      const struct dd_function_table *driverFunctions,
 931                      void *driverContext)
 932 {
 933    GLcontext *ctx;
 934
 935    ASSERT(visual);
 936    /*ASSERT(driverContext);*/
 937
 938    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
 939    if (!ctx)
 940       return NULL;
 941
 942    if (_mesa_initialize_context(ctx, visual, share_list,
 943                                 driverFunctions, driverContext)) {
 944       return ctx;
 945    }
 946    else {
 947       _mesa_free(ctx);
 948       return NULL;
 949    }
 950 }
 951
 952
 953 /**
 954  * Free the data associated with the given context.
 955  *
 956  * But doesn't free the GLcontext struct itself.
 957  *
 958  * \sa _mesa_initialize_context() and init_attrib_groups().
 959  */
 960 void
 961 _mesa_free_context_data( GLcontext *ctx )
 962 {
 963    GLint RefCount;
 964
 965    if (!_mesa_get_current_context()){
 966       /* No current context, but we may need one in order to delete
 967        * texture objs, etc.  So temporarily bind the context now.
 968        */
 969       _mesa_make_current(ctx, NULL, NULL);
 970    }
 971
 972    /* unreference WinSysDraw/Read buffers */
 973    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
 974    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
 975    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
 976    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
 977
 978    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
 979    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 980    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
 981
 982    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
 983    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 984    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
 985
 986 #if FEATURE_attrib_stack
 987    _mesa_free_attrib_data(ctx);
 988 #endif
 989    _mesa_free_lighting_data( ctx );
 990 #if FEATURE_evaluators
 991    _mesa_free_eval_data( ctx );
 992 #endif
 993    _mesa_free_texture_data( ctx );
 994    _mesa_free_matrix_data( ctx );
 995    _mesa_free_viewport_data( ctx );
 996 #if FEATURE_colortable
 997    _mesa_free_colortables_data( ctx );
 998 #endif
 999    _mesa_free_program_data(ctx);
1000    _mesa_free_shader_state(ctx);
1001 #if FEATURE_ARB_occlusion_query
1002    _mesa_free_query_data(ctx);
1003 #endif
1004
1005 #if FEATURE_ARB_vertex_buffer_object
1006    _mesa_delete_buffer_object(ctx, ctx->Array.NullBufferObj);
1007 #endif
1008    _mesa_delete_array_object(ctx, ctx->Array.DefaultArrayObj);
1009
1010    /* free dispatch tables */
1011    _mesa_free(ctx->Exec);
1012    _mesa_free(ctx->Save);
1013
1014    /* Shared context state (display lists, textures, etc) */
1015    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1016    RefCount = --ctx->Shared->RefCount;
1017    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1018    assert(RefCount >= 0);
1019    if (RefCount == 0) {
1020       /* free shared state */
1021       _mesa_free_shared_state( ctx, ctx->Shared );
1022    }
1023
1024    if (ctx->Extensions.String)
1025       _mesa_free((void *) ctx->Extensions.String);
1026
1027    /* unbind the context if it's currently bound */
1028    if (ctx == _mesa_get_current_context()) {
1029       _mesa_make_current(NULL, NULL, NULL);
1030    }
1031 }
1032
1033
1034 /**
1035  * Destroy a GLcontext structure.
1036  *
1037  * \param ctx GL context.
1038  *
1039  * Calls _mesa_free_context_data() and frees the GLcontext structure itself.
1040  */
1041 void
1042 _mesa_destroy_context( GLcontext *ctx )
1043 {
1044    if (ctx) {
1045       _mesa_free_context_data(ctx);
1046       _mesa_free( (void *) ctx );
1047    }
1048 }
1049
1050
1051 #if _HAVE_FULL_GL
1052 /**
1053  * Copy attribute groups from one context to another.
1054  *
1055  * \param src source context
1056  * \param dst destination context
1057  * \param mask bitwise OR of GL_*_BIT flags
1058  *
1059  * According to the bits specified in \p mask, copies the corresponding
1060  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1061  * memcpy is not enough due to the existence of internal pointers in their data
1062  * structures.
1063  */
1064 void
1065 _mesa_copy_context( const GLcontext *src, GLcontext *dst, GLuint mask )
1066 {
1067    if (mask & GL_ACCUM_BUFFER_BIT) {
1068       /* OK to memcpy */
1069       dst->Accum = src->Accum;
1070    }
1071    if (mask & GL_COLOR_BUFFER_BIT) {
1072       /* OK to memcpy */
1073       dst->Color = src->Color;
1074    }
1075    if (mask & GL_CURRENT_BIT) {
1076       /* OK to memcpy */
1077       dst->Current = src->Current;
1078    }
1079    if (mask & GL_DEPTH_BUFFER_BIT) {
1080       /* OK to memcpy */
1081       dst->Depth = src->Depth;
1082    }
1083    if (mask & GL_ENABLE_BIT) {
1084       /* no op */
1085    }
1086    if (mask & GL_EVAL_BIT) {
1087       /* OK to memcpy */
1088       dst->Eval = src->Eval;
1089    }
1090    if (mask & GL_FOG_BIT) {
1091       /* OK to memcpy */
1092       dst->Fog = src->Fog;
1093    }
1094    if (mask & GL_HINT_BIT) {
1095       /* OK to memcpy */
1096       dst->Hint = src->Hint;
1097    }
1098    if (mask & GL_LIGHTING_BIT) {
1099       GLuint i;
1100       /* begin with memcpy */
1101       dst->Light = src->Light;
1102       /* fixup linked lists to prevent pointer insanity */
1103       make_empty_list( &(dst->Light.EnabledList) );
1104       for (i = 0; i < MAX_LIGHTS; i++) {
1105          if (dst->Light.Light[i].Enabled) {
1106             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1107          }
1108       }
1109    }
1110    if (mask & GL_LINE_BIT) {
1111       /* OK to memcpy */
1112       dst->Line = src->Line;
1113    }
1114    if (mask & GL_LIST_BIT) {
1115       /* OK to memcpy */
1116       dst->List = src->List;
1117    }
1118    if (mask & GL_PIXEL_MODE_BIT) {
1119       /* OK to memcpy */
1120       dst->Pixel = src->Pixel;
1121    }
1122    if (mask & GL_POINT_BIT) {
1123       /* OK to memcpy */
1124       dst->Point = src->Point;
1125    }
1126    if (mask & GL_POLYGON_BIT) {
1127       /* OK to memcpy */
1128       dst->Polygon = src->Polygon;
1129    }
1130    if (mask & GL_POLYGON_STIPPLE_BIT) {
1131       /* Use loop instead of MEMCPY due to problem with Portland Group's
1132        * C compiler.  Reported by John Stone.
1133        */
1134       GLuint i;
1135       for (i = 0; i < 32; i++) {
1136          dst->PolygonStipple[i] = src->PolygonStipple[i];
1137       }
1138    }
1139    if (mask & GL_SCISSOR_BIT) {
1140       /* OK to memcpy */
1141       dst->Scissor = src->Scissor;
1142    }
1143    if (mask & GL_STENCIL_BUFFER_BIT) {
1144       /* OK to memcpy */
1145       dst->Stencil = src->Stencil;
1146    }
1147    if (mask & GL_TEXTURE_BIT) {
1148       /* Cannot memcpy because of pointers */
1149       _mesa_copy_texture_state(src, dst);
1150    }
1151    if (mask & GL_TRANSFORM_BIT) {
1152       /* OK to memcpy */
1153       dst->Transform = src->Transform;
1154    }
1155    if (mask & GL_VIEWPORT_BIT) {
1156       /* Cannot use memcpy, because of pointers in GLmatrix _WindowMap */
1157       dst->Viewport.X = src->Viewport.X;
1158       dst->Viewport.Y = src->Viewport.Y;
1159       dst->Viewport.Width = src->Viewport.Width;
1160       dst->Viewport.Height = src->Viewport.Height;
1161       dst->Viewport.Near = src->Viewport.Near;
1162       dst->Viewport.Far = src->Viewport.Far;
1163       _math_matrix_copy(&dst->Viewport._WindowMap, &src->Viewport._WindowMap);
1164    }
1165
1166    /* XXX FIXME:  Call callbacks?
1167     */
1168    dst->NewState = _NEW_ALL;
1169 }
1170 #endif
1171
1172
1173 /**
1174  * Check if the given context can render into the given framebuffer
1175  * by checking visual attributes.
1176  *
1177  * Most of these tests could go away because Mesa is now pretty flexible
1178  * in terms of mixing rendering contexts with framebuffers.  As long
1179  * as RGB vs. CI mode agree, we're probably good.
1180  *
1181  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1182  */
1183 static GLboolean
1184 check_compatible(const GLcontext *ctx, const GLframebuffer *buffer)
1185 {
1186    const GLvisual *ctxvis = &ctx->Visual;
1187    const GLvisual *bufvis = &buffer->Visual;
1188
1189    if (ctxvis == bufvis)
1190       return GL_TRUE;
1191
1192    if (ctxvis->rgbMode != bufvis->rgbMode)
1193       return GL_FALSE;
1194 #if 0
1195    /* disabling this fixes the fgl_glxgears pbuffer demo */
1196    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1197       return GL_FALSE;
1198 #endif
1199    if (ctxvis->stereoMode && !bufvis->stereoMode)
1200       return GL_FALSE;
1201    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1202       return GL_FALSE;
1203    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1204       return GL_FALSE;
1205    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1206       return GL_FALSE;
1207    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1208       return GL_FALSE;
1209    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1210       return GL_FALSE;
1211    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1212       return GL_FALSE;
1213 #if 0
1214    /* disabled (see bug 11161) */
1215    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1216       return GL_FALSE;
1217 #endif
1218    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1219       return GL_FALSE;
1220
1221    return GL_TRUE;
1222 }
1223
1224
1225 /**
1226  * Do one-time initialization for the given framebuffer.  Specifically,
1227  * ask the driver for the window's current size and update the framebuffer
1228  * object to match.
1229  * Really, the device driver should totally take care of this.
1230  */
1231 static void
1232 initialize_framebuffer_size(GLcontext *ctx, GLframebuffer *fb)
1233 {
1234    GLuint width, height;
1235    if (ctx->Driver.GetBufferSize) {
1236       ctx->Driver.GetBufferSize(fb, &width, &height);
1237       if (ctx->Driver.ResizeBuffers)
1238          ctx->Driver.ResizeBuffers(ctx, fb, width, height);
1239       fb->Initialized = GL_TRUE;
1240    }
1241 }
1242
1243
1244 /**
1245  * Bind the given context to the given drawBuffer and readBuffer and
1246  * make it the current context for the calling thread.
1247  * We'll render into the drawBuffer and read pixels from the
1248  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1249  *
1250  * We check that the context's and framebuffer's visuals are compatible
1251  * and return immediately if they're not.
1252  *
1253  * \param newCtx  the new GL context. If NULL then there will be no current GL
1254  *                context.
1255  * \param drawBuffer  the drawing framebuffer
1256  * \param readBuffer  the reading framebuffer
1257  */
1258 void
1259 _mesa_make_current( GLcontext *newCtx, GLframebuffer *drawBuffer,
1260                     GLframebuffer *readBuffer )
1261 {
1262    if (MESA_VERBOSE & VERBOSE_API)
1263       _mesa_debug(newCtx, "_mesa_make_current()\n");
1264
1265    /* Check that the context's and framebuffer's visuals are compatible.
1266     */
1267    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1268       if (!check_compatible(newCtx, drawBuffer)) {
1269          _mesa_warning(newCtx,
1270               "MakeCurrent: incompatible visuals for context and drawbuffer");
1271          return;
1272       }
1273    }
1274    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1275       if (!check_compatible(newCtx, readBuffer)) {
1276          _mesa_warning(newCtx,
1277               "MakeCurrent: incompatible visuals for context and readbuffer");
1278          return;
1279       }
1280    }
1281
1282    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1283    _glapi_set_context((void *) newCtx);
1284    ASSERT(_mesa_get_current_context() == newCtx);
1285
1286    if (!newCtx) {
1287       _glapi_set_dispatch(NULL);  /* none current */
1288    }
1289    else {
1290       _glapi_set_dispatch(newCtx->CurrentDispatch);
1291
1292       if (drawBuffer && readBuffer) {
1293          /* TODO: check if newCtx and buffer's visual match??? */
1294
1295          ASSERT(drawBuffer->Name == 0);
1296          ASSERT(readBuffer->Name == 0);
1297          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1298          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1299
1300          /*
1301           * Only set the context's Draw/ReadBuffer fields if they're NULL
1302           * or not bound to a user-created FBO.
1303           */
1304          if (!newCtx->DrawBuffer || newCtx->DrawBuffer->Name == 0) {
1305             /* KW: merge conflict here, revisit.
1306              */
1307             /* fix up the fb fields - these will end up wrong otherwise
1308              * if the DRIdrawable changes, and everything relies on them.
1309              * This is a bit messy (same as needed in _mesa_BindFramebufferEXT)
1310              */
1311             unsigned int i;
1312             GLenum buffers[MAX_DRAW_BUFFERS];
1313
1314             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1315
1316             for(i = 0; i < newCtx->Const.MaxDrawBuffers; i++) {
1317                buffers[i] = newCtx->Color.DrawBuffer[i];
1318             }
1319
1320             _mesa_drawbuffers(newCtx, newCtx->Const.MaxDrawBuffers, buffers, NULL);
1321          }
1322          if (!newCtx->ReadBuffer || newCtx->ReadBuffer->Name == 0) {
1323             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1324          }
1325
1326          /* XXX only set this flag if we're really changing the draw/read
1327           * framebuffer bindings.
1328           */
1329          newCtx->NewState |= _NEW_BUFFERS;
1330
1331 #if 1
1332          /* We want to get rid of these lines: */
1333
1334 #if _HAVE_FULL_GL
1335          if (!drawBuffer->Initialized) {
1336             initialize_framebuffer_size(newCtx, drawBuffer);
1337          }
1338          if (readBuffer != drawBuffer && !readBuffer->Initialized) {
1339             initialize_framebuffer_size(newCtx, readBuffer);
1340          }
1341
1342          _mesa_resizebuffers(newCtx);
1343 #endif
1344
1345 #else
1346          /* We want the drawBuffer and readBuffer to be initialized by
1347           * the driver.
1348           * This generally means the Width and Height match the actual
1349           * window size and the renderbuffers (both hardware and software
1350           * based) are allocated to match.  The later can generally be
1351           * done with a call to _mesa_resize_framebuffer().
1352           *
1353           * It's theoretically possible for a buffer to have zero width
1354           * or height, but for now, assert check that the driver did what's
1355           * expected of it.
1356           */
1357          ASSERT(drawBuffer->Width > 0);
1358          ASSERT(drawBuffer->Height > 0);
1359 #endif
1360
1361          if (newCtx->FirstTimeCurrent) {
1362             /* set initial viewport and scissor size now */
1363             _mesa_set_viewport(newCtx, 0, 0,
1364                                drawBuffer->Width, drawBuffer->Height);
1365             _mesa_set_scissor(newCtx, 0, 0,
1366                               drawBuffer->Width, drawBuffer->Height );
1367             check_context_limits(newCtx);
1368          }
1369       }
1370
1371       /* We can use this to help debug user's problems.  Tell them to set
1372        * the MESA_INFO env variable before running their app.  Then the
1373        * first time each context is made current we'll print some useful
1374        * information.
1375        */
1376       if (newCtx->FirstTimeCurrent) {
1377          if (_mesa_getenv("MESA_INFO")) {
1378             _mesa_print_info();
1379          }
1380          newCtx->FirstTimeCurrent = GL_FALSE;
1381       }
1382    }
1383 }
1384
1385
1386 /**
1387  * Make context 'ctx' share the display lists, textures and programs
1388  * that are associated with 'ctxToShare'.
1389  * Any display lists, textures or programs associated with 'ctx' will
1390  * be deleted if nobody else is sharing them.
1391  */
1392 GLboolean
1393 _mesa_share_state(GLcontext *ctx, GLcontext *ctxToShare)
1394 {
1395    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1396       struct gl_shared_state *oldSharedState = ctx->Shared;
1397
1398       ctx->Shared = ctxToShare->Shared;
1399       ctx->Shared->RefCount++;
1400
1401       update_default_objects(ctx);
1402
1403       oldSharedState->RefCount--;
1404       if (oldSharedState->RefCount == 0) {
1405          _mesa_free_shared_state(ctx, oldSharedState);
1406       }
1407
1408       return GL_TRUE;
1409    }
1410    else {
1411       return GL_FALSE;
1412    }
1413 }
1414
1415
1416
1417 /**
1418  * \return pointer to the current GL context for this thread.
1419  *
1420  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1421  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1422  * context.h.
1423  */
1424 GLcontext *
1425 _mesa_get_current_context( void )
1426 {
1427    return (GLcontext *) _glapi_get_context();
1428 }
1429
1430
1431 /**
1432  * Get context's current API dispatch table.
1433  *
1434  * It'll either be the immediate-mode execute dispatcher or the display list
1435  * compile dispatcher.
1436  *
1437  * \param ctx GL context.
1438  *
1439  * \return pointer to dispatch_table.
1440  *
1441  * Simply returns __GLcontextRec::CurrentDispatch.
1442  */
1443 struct _glapi_table *
1444 _mesa_get_dispatch(GLcontext *ctx)
1445 {
1446    return ctx->CurrentDispatch;
1447 }
1448
1449 /*@}*/
1450
1451
1452 /**********************************************************************/
1453 /** \name Miscellaneous functions                                     */
1454 /**********************************************************************/
1455 /*@{*/
1456
1457 /**
1458  * Record an error.
1459  *
1460  * \param ctx GL context.
1461  * \param error error code.
1462  *
1463  * Records the given error code and call the driver's dd_function_table::Error
1464  * function if defined.
1465  *
1466  * \sa
1467  * This is called via _mesa_error().
1468  */
1469 void
1470 _mesa_record_error(GLcontext *ctx, GLenum error)
1471 {
1472    if (!ctx)
1473       return;
1474
1475    if (ctx->ErrorValue == GL_NO_ERROR) {
1476       ctx->ErrorValue = error;
1477    }
1478
1479    /* Call device driver's error handler, if any.  This is used on the Mac. */
1480    if (ctx->Driver.Error) {
1481       ctx->Driver.Error(ctx);
1482    }
1483 }
1484
1485
1486 /**
1487  * Execute glFinish().
1488  *
1489  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1490  * dd_function_table::Finish driver callback, if not NULL.
1491  */
1492 void GLAPIENTRY
1493 _mesa_Finish(void)
1494 {
1495    GET_CURRENT_CONTEXT(ctx);
1496    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1497    if (ctx->Driver.Finish) {
1498       ctx->Driver.Finish(ctx);
1499    }
1500 }
1501
1502
1503 /**
1504  * Execute glFlush().
1505  *
1506  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1507  * dd_function_table::Flush driver callback, if not NULL.
1508  */
1509 void GLAPIENTRY
1510 _mesa_Flush(void)
1511 {
1512    GET_CURRENT_CONTEXT(ctx);
1513    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1514    if (ctx->Driver.Flush) {
1515       ctx->Driver.Flush(ctx);
1516    }
1517 }
1518
1519
1520 /*@}*/