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 ctx 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_CURRENT( 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    /* GL_ATI_envmap_bumpmap */
 593    ctx->Const.SupportedBumpUnits = SUPPORTED_ATI_BUMP_UNITS;
 594
 595    /* sanity checks */
 596    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
 597                                              ctx->Const.MaxTextureCoordUnits));
 598    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 599    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 600
 601    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 602    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 603    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
 604    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
 605 }
 606
 607
 608 /**
 609  * Do some sanity checks on the limits/constants for the given context.
 610  * Only called the first time a context is bound.
 611  */
 612 static void
 613 check_context_limits(GLcontext *ctx)
 614 {
 615    /* Many context limits/constants are limited by the size of
 616     * internal arrays.
 617     */
 618    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 619    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 620    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 621    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 622
 623    /* number of coord units cannot be greater than number of image units */
 624    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.MaxTextureImageUnits);
 625
 626    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 627    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 628    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 629    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 630
 631    /* make sure largest texture image is <= MAX_WIDTH in size */
 632    assert((1 << (ctx->Const.MaxTextureLevels - 1)) <= MAX_WIDTH);
 633    assert((1 << (ctx->Const.MaxCubeTextureLevels - 1)) <= MAX_WIDTH);
 634    assert((1 << (ctx->Const.Max3DTextureLevels - 1)) <= MAX_WIDTH);
 635
 636    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
 637    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
 638
 639    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 640
 641    /* XXX probably add more tests */
 642 }
 643
 644
 645 /**
 646  * Initialize the attribute groups in a GL context.
 647  *
 648  * \param ctx GL context.
 649  *
 650  * Initializes all the attributes, calling the respective <tt>init*</tt>
 651  * functions for the more complex data structures.
 652  */
 653 static GLboolean
 654 init_attrib_groups(GLcontext *ctx)
 655 {
 656    assert(ctx);
 657
 658    /* Constants */
 659    _mesa_init_constants( ctx );
 660
 661    /* Extensions */
 662    _mesa_init_extensions( ctx );
 663
 664    /* Attribute Groups */
 665 #if FEATURE_accum
 666    _mesa_init_accum( ctx );
 667 #endif
 668 #if FEATURE_attrib_stack
 669    _mesa_init_attrib( ctx );
 670 #endif
 671    _mesa_init_buffer_objects( ctx );
 672    _mesa_init_color( ctx );
 673 #if FEATURE_colortable
 674    _mesa_init_colortables( ctx );
 675 #endif
 676    _mesa_init_current( ctx );
 677    _mesa_init_depth( ctx );
 678    _mesa_init_debug( ctx );
 679 #if FEATURE_dlist
 680    _mesa_init_display_list( ctx );
 681 #endif
 682 #if FEATURE_evaluators
 683    _mesa_init_eval( ctx );
 684 #endif
 685    _mesa_init_fbobjects( ctx );
 686 #if FEATURE_feedback
 687    _mesa_init_feedback( ctx );
 688 #else
 689    ctx->RenderMode = GL_RENDER;
 690 #endif
 691    _mesa_init_fog( ctx );
 692 #if FEATURE_histogram
 693    _mesa_init_histogram( ctx );
 694 #endif
 695    _mesa_init_hint( ctx );
 696    _mesa_init_line( ctx );
 697    _mesa_init_lighting( ctx );
 698    _mesa_init_matrix( ctx );
 699    _mesa_init_multisample( ctx );
 700    _mesa_init_pixel( ctx );
 701    _mesa_init_pixelstore( ctx );
 702    _mesa_init_point( ctx );
 703    _mesa_init_polygon( ctx );
 704    _mesa_init_program( ctx );
 705 #if FEATURE_ARB_occlusion_query
 706    _mesa_init_query( ctx );
 707 #endif
 708 #if FEATURE_drawpix
 709    _mesa_init_rastpos( ctx );
 710 #endif
 711    _mesa_init_scissor( ctx );
 712    _mesa_init_shader_state( ctx );
 713    _mesa_init_stencil( ctx );
 714    _mesa_init_transform( ctx );
 715    _mesa_init_varray( ctx );
 716    _mesa_init_viewport( ctx );
 717
 718    if (!_mesa_init_texture( ctx ))
 719       return GL_FALSE;
 720
 721 #if FEATURE_texture_s3tc
 722    _mesa_init_texture_s3tc( ctx );
 723 #endif
 724 #if FEATURE_texture_fxt1
 725    _mesa_init_texture_fxt1( ctx );
 726 #endif
 727
 728    /* Miscellaneous */
 729    ctx->NewState = _NEW_ALL;
 730    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
 731    ctx->varying_vp_inputs = ~0;
 732
 733    return GL_TRUE;
 734 }
 735
 736
 737 /**
 738  * Update default objects in a GL context with respect to shared state.
 739  *
 740  * \param ctx GL context.
 741  *
 742  * Removes references to old default objects, (texture objects, program
 743  * objects, etc.) and changes to reference those from the current shared
 744  * state.
 745  */
 746 static GLboolean
 747 update_default_objects(GLcontext *ctx)
 748 {
 749    assert(ctx);
 750
 751    _mesa_update_default_objects_program(ctx);
 752    _mesa_update_default_objects_texture(ctx);
 753    _mesa_update_default_objects_buffer_objects(ctx);
 754
 755    return GL_TRUE;
 756 }
 757
 758
 759 /**
 760  * This is the default function we plug into all dispatch table slots
 761  * This helps prevents a segfault when someone calls a GL function without
 762  * first checking if the extension's supported.
 763  */
 764 static int
 765 generic_nop(void)
 766 {
 767    _mesa_warning(NULL, "User called no-op dispatch function (an unsupported extension function?)");
 768    return 0;
 769 }
 770
 771
 772 /**
 773  * Allocate and initialize a new dispatch table.
 774  */
 775 static struct _glapi_table *
 776 alloc_dispatch_table(void)
 777 {
 778    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
 779     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
 780     * Mesa we do this to accomodate different versions of libGL and various
 781     * DRI drivers.
 782     */
 783    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
 784                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
 785    struct _glapi_table *table =
 786       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
 787    if (table) {
 788       _glapi_proc *entry = (_glapi_proc *) table;
 789       GLint i;
 790       for (i = 0; i < numEntries; i++) {
 791          entry[i] = (_glapi_proc) generic_nop;
 792       }
 793    }
 794    return table;
 795 }
 796
 797
 798 /**
 799  * Initialize a GLcontext struct (rendering context).
 800  *
 801  * This includes allocating all the other structs and arrays which hang off of
 802  * the context by pointers.
 803  * Note that the driver needs to pass in its dd_function_table here since
 804  * we need to at least call driverFunctions->NewTextureObject to create the
 805  * default texture objects.
 806  *
 807  * Called by _mesa_create_context().
 808  *
 809  * Performs the imports and exports callback tables initialization, and
 810  * miscellaneous one-time initializations. If no shared context is supplied one
 811  * is allocated, and increase its reference count.  Setups the GL API dispatch
 812  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
 813  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
 814  * for debug flags.
 815  *
 816  * \param ctx the context to initialize
 817  * \param visual describes the visual attributes for this context
 818  * \param share_list points to context to share textures, display lists,
 819  *        etc with, or NULL
 820  * \param driverFunctions table of device driver functions for this context
 821  *        to use
 822  * \param driverContext pointer to driver-specific context data
 823  */
 824 GLboolean
 825 _mesa_initialize_context(GLcontext *ctx,
 826                          const GLvisual *visual,
 827                          GLcontext *share_list,
 828                          const struct dd_function_table *driverFunctions,
 829                          void *driverContext)
 830 {
 831    struct gl_shared_state *shared;
 832
 833    /*ASSERT(driverContext);*/
 834    assert(driverFunctions->NewTextureObject);
 835    assert(driverFunctions->FreeTexImageData);
 836
 837    /* misc one-time initializations */
 838    one_time_init(ctx);
 839
 840    ctx->Visual = *visual;
 841    ctx->DrawBuffer = NULL;
 842    ctx->ReadBuffer = NULL;
 843    ctx->WinSysDrawBuffer = NULL;
 844    ctx->WinSysReadBuffer = NULL;
 845
 846    /* Plug in driver functions and context pointer here.
 847     * This is important because when we call alloc_shared_state() below
 848     * we'll call ctx->Driver.NewTextureObject() to create the default
 849     * textures.
 850     */
 851    ctx->Driver = *driverFunctions;
 852    ctx->DriverCtx = driverContext;
 853
 854    if (share_list) {
 855       /* share state with another context */
 856       shared = share_list->Shared;
 857    }
 858    else {
 859       /* allocate new, unshared state */
 860       shared = _mesa_alloc_shared_state(ctx);
 861       if (!shared)
 862          return GL_FALSE;
 863    }
 864
 865    _glthread_LOCK_MUTEX(shared->Mutex);
 866    ctx->Shared = shared;
 867    shared->RefCount++;
 868    _glthread_UNLOCK_MUTEX(shared->Mutex);
 869
 870    if (!init_attrib_groups( ctx )) {
 871       _mesa_free_shared_state(ctx, ctx->Shared);
 872       return GL_FALSE;
 873    }
 874
 875    /* setup the API dispatch tables */
 876    ctx->Exec = alloc_dispatch_table();
 877    ctx->Save = alloc_dispatch_table();
 878    if (!ctx->Exec || !ctx->Save) {
 879       _mesa_free_shared_state(ctx, ctx->Shared);
 880       if (ctx->Exec)
 881          _mesa_free(ctx->Exec);
 882    }
 883 #if FEATURE_dispatch
 884    _mesa_init_exec_table(ctx->Exec);
 885 #endif
 886    ctx->CurrentDispatch = ctx->Exec;
 887 #if FEATURE_dlist
 888    _mesa_init_dlist_table(ctx->Save);
 889    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
 890 #endif
 891    /* Neutral tnl module stuff */
 892    _mesa_init_exec_vtxfmt( ctx );
 893    ctx->TnlModule.Current = NULL;
 894    ctx->TnlModule.SwapCount = 0;
 895
 896    ctx->FragmentProgram._MaintainTexEnvProgram
 897       = (_mesa_getenv("MESA_TEX_PROG") != NULL);
 898
 899    ctx->VertexProgram._MaintainTnlProgram
 900       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
 901    if (ctx->VertexProgram._MaintainTnlProgram) {
 902       /* this is required... */
 903       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
 904    }
 905
 906 #ifdef FEATURE_extra_context_init
 907    _mesa_initialize_context_extra(ctx);
 908 #endif
 909
 910    ctx->FirstTimeCurrent = GL_TRUE;
 911
 912    return GL_TRUE;
 913 }
 914
 915
 916 /**
 917  * Allocate and initialize a GLcontext structure.
 918  * Note that the driver needs to pass in its dd_function_table here since
 919  * we need to at least call driverFunctions->NewTextureObject to initialize
 920  * the rendering context.
 921  *
 922  * \param visual a GLvisual pointer (we copy the struct contents)
 923  * \param share_list another context to share display lists with or NULL
 924  * \param driverFunctions points to the dd_function_table into which the
 925  *        driver has plugged in all its special functions.
 926  * \param driverContext points to the device driver's private context state
 927  *
 928  * \return pointer to a new __GLcontextRec or NULL if error.
 929  */
 930 GLcontext *
 931 _mesa_create_context(const GLvisual *visual,
 932                      GLcontext *share_list,
 933                      const struct dd_function_table *driverFunctions,
 934                      void *driverContext)
 935 {
 936    GLcontext *ctx;
 937
 938    ASSERT(visual);
 939    /*ASSERT(driverContext);*/
 940
 941    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
 942    if (!ctx)
 943       return NULL;
 944
 945    if (_mesa_initialize_context(ctx, visual, share_list,
 946                                 driverFunctions, driverContext)) {
 947       return ctx;
 948    }
 949    else {
 950       _mesa_free(ctx);
 951       return NULL;
 952    }
 953 }
 954
 955
 956 /**
 957  * Free the data associated with the given context.
 958  *
 959  * But doesn't free the GLcontext struct itself.
 960  *
 961  * \sa _mesa_initialize_context() and init_attrib_groups().
 962  */
 963 void
 964 _mesa_free_context_data( GLcontext *ctx )
 965 {
 966    GLint RefCount;
 967
 968    if (!_mesa_get_current_context()){
 969       /* No current context, but we may need one in order to delete
 970        * texture objs, etc.  So temporarily bind the context now.
 971        */
 972       _mesa_make_current(ctx, NULL, NULL);
 973    }
 974
 975    /* unreference WinSysDraw/Read buffers */
 976    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
 977    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
 978    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
 979    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
 980
 981    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
 982    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 983    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
 984
 985    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
 986    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 987    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
 988
 989 #if FEATURE_attrib_stack
 990    _mesa_free_attrib_data(ctx);
 991 #endif
 992    _mesa_free_lighting_data( ctx );
 993 #if FEATURE_evaluators
 994    _mesa_free_eval_data( ctx );
 995 #endif
 996    _mesa_free_texture_data( ctx );
 997    _mesa_free_matrix_data( ctx );
 998    _mesa_free_viewport_data( ctx );
 999 #if FEATURE_colortable
1000    _mesa_free_colortables_data( ctx );
1001 #endif
1002    _mesa_free_program_data(ctx);
1003    _mesa_free_shader_state(ctx);
1004 #if FEATURE_ARB_occlusion_query
1005    _mesa_free_query_data(ctx);
1006 #endif
1007
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       GLint RefCount;
1398
1399       ctx->Shared = ctxToShare->Shared;
1400
1401       _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1402       ctx->Shared->RefCount++;
1403       _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1404
1405       update_default_objects(ctx);
1406
1407       _glthread_LOCK_MUTEX(oldSharedState->Mutex);
1408       RefCount = --oldSharedState->RefCount;
1409       _glthread_UNLOCK_MUTEX(oldSharedState->Mutex);
1410
1411       if (RefCount == 0) {
1412          _mesa_free_shared_state(ctx, oldSharedState);
1413       }
1414
1415       return GL_TRUE;
1416    }
1417    else {
1418       return GL_FALSE;
1419    }
1420 }
1421
1422
1423
1424 /**
1425  * \return pointer to the current GL context for this thread.
1426  *
1427  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1428  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1429  * context.h.
1430  */
1431 GLcontext *
1432 _mesa_get_current_context( void )
1433 {
1434    return (GLcontext *) _glapi_get_context();
1435 }
1436
1437
1438 /**
1439  * Get context's current API dispatch table.
1440  *
1441  * It'll either be the immediate-mode execute dispatcher or the display list
1442  * compile dispatcher.
1443  *
1444  * \param ctx GL context.
1445  *
1446  * \return pointer to dispatch_table.
1447  *
1448  * Simply returns __GLcontextRec::CurrentDispatch.
1449  */
1450 struct _glapi_table *
1451 _mesa_get_dispatch(GLcontext *ctx)
1452 {
1453    return ctx->CurrentDispatch;
1454 }
1455
1456 /*@}*/
1457
1458
1459 /**********************************************************************/
1460 /** \name Miscellaneous functions                                     */
1461 /**********************************************************************/
1462 /*@{*/
1463
1464 /**
1465  * Record an error.
1466  *
1467  * \param ctx GL context.
1468  * \param error error code.
1469  *
1470  * Records the given error code and call the driver's dd_function_table::Error
1471  * function if defined.
1472  *
1473  * \sa
1474  * This is called via _mesa_error().
1475  */
1476 void
1477 _mesa_record_error(GLcontext *ctx, GLenum error)
1478 {
1479    if (!ctx)
1480       return;
1481
1482    if (ctx->ErrorValue == GL_NO_ERROR) {
1483       ctx->ErrorValue = error;
1484    }
1485
1486    /* Call device driver's error handler, if any.  This is used on the Mac. */
1487    if (ctx->Driver.Error) {
1488       ctx->Driver.Error(ctx);
1489    }
1490 }
1491
1492
1493 /**
1494  * Execute glFinish().
1495  *
1496  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1497  * dd_function_table::Finish driver callback, if not NULL.
1498  */
1499 void GLAPIENTRY
1500 _mesa_Finish(void)
1501 {
1502    GET_CURRENT_CONTEXT(ctx);
1503    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1504    FLUSH_CURRENT( ctx, 0 );
1505    if (ctx->Driver.Finish) {
1506       ctx->Driver.Finish(ctx);
1507    }
1508 }
1509
1510
1511 /**
1512  * Execute glFlush().
1513  *
1514  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1515  * dd_function_table::Flush driver callback, if not NULL.
1516  */
1517 void GLAPIENTRY
1518 _mesa_Flush(void)
1519 {
1520    GET_CURRENT_CONTEXT(ctx);
1521    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1522    FLUSH_CURRENT( ctx, 0 );
1523    if (ctx->Driver.Flush) {
1524       ctx->Driver.Flush(ctx);
1525    }
1526 }
1527
1528
1529 /**
1530  * Set mvp_with_dp4 flag.  If a driver has a preference for DP4 over
1531  * MUL/MAD, or vice versa, call this function to register that.
1532  * Otherwise we default to MUL/MAD.
1533  */
1534 void
1535 _mesa_set_mvp_with_dp4( GLcontext *ctx,
1536                         GLboolean flag )
1537 {
1538    ctx->mvp_with_dp4 = flag;
1539 }
1540
1541
1542 /*@}*/