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 < Elements(ctx->Current.Attrib); 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    /* GL_EXT_provoking_vertex */
 596    ctx->Const.QuadsFollowProvokingVertexConvention = GL_TRUE;
 597
 598    /* sanity checks */
 599    ASSERT(ctx->Const.MaxTextureUnits == MIN2(ctx->Const.MaxTextureImageUnits,
 600                                              ctx->Const.MaxTextureCoordUnits));
 601    ASSERT(ctx->Const.FragmentProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 602    ASSERT(ctx->Const.VertexProgram.MaxLocalParams <= MAX_PROGRAM_LOCAL_PARAMS);
 603
 604    ASSERT(MAX_NV_FRAGMENT_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 605    ASSERT(MAX_NV_VERTEX_PROGRAM_TEMPS <= MAX_PROGRAM_TEMPS);
 606    ASSERT(MAX_NV_VERTEX_PROGRAM_INPUTS <= VERT_ATTRIB_MAX);
 607    ASSERT(MAX_NV_VERTEX_PROGRAM_OUTPUTS <= VERT_RESULT_MAX);
 608
 609    /* check that we don't exceed various 32-bit bitfields */
 610    ASSERT(VERT_RESULT_MAX <= 32);
 611    ASSERT(FRAG_ATTRIB_MAX <= 32);
 612 }
 613
 614
 615 /**
 616  * Do some sanity checks on the limits/constants for the given context.
 617  * Only called the first time a context is bound.
 618  */
 619 static void
 620 check_context_limits(GLcontext *ctx)
 621 {
 622    /* Many context limits/constants are limited by the size of
 623     * internal arrays.
 624     */
 625    assert(ctx->Const.MaxTextureImageUnits <= MAX_TEXTURE_IMAGE_UNITS);
 626    assert(ctx->Const.MaxTextureCoordUnits <= MAX_TEXTURE_COORD_UNITS);
 627    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_IMAGE_UNITS);
 628    assert(ctx->Const.MaxTextureUnits <= MAX_TEXTURE_COORD_UNITS);
 629
 630    /* number of coord units cannot be greater than number of image units */
 631    assert(ctx->Const.MaxTextureCoordUnits <= ctx->Const.MaxTextureImageUnits);
 632
 633    assert(ctx->Const.MaxTextureLevels <= MAX_TEXTURE_LEVELS);
 634    assert(ctx->Const.Max3DTextureLevels <= MAX_3D_TEXTURE_LEVELS);
 635    assert(ctx->Const.MaxCubeTextureLevels <= MAX_CUBE_TEXTURE_LEVELS);
 636    assert(ctx->Const.MaxTextureRectSize <= MAX_TEXTURE_RECT_SIZE);
 637
 638    /* make sure largest texture image is <= MAX_WIDTH in size */
 639    assert((1 << (ctx->Const.MaxTextureLevels - 1)) <= MAX_WIDTH);
 640    assert((1 << (ctx->Const.MaxCubeTextureLevels - 1)) <= MAX_WIDTH);
 641    assert((1 << (ctx->Const.Max3DTextureLevels - 1)) <= MAX_WIDTH);
 642
 643    assert(ctx->Const.MaxViewportWidth <= MAX_WIDTH);
 644    assert(ctx->Const.MaxViewportHeight <= MAX_WIDTH);
 645
 646    assert(ctx->Const.MaxDrawBuffers <= MAX_DRAW_BUFFERS);
 647
 648    /* XXX probably add more tests */
 649 }
 650
 651
 652 /**
 653  * Initialize the attribute groups in a GL context.
 654  *
 655  * \param ctx GL context.
 656  *
 657  * Initializes all the attributes, calling the respective <tt>init*</tt>
 658  * functions for the more complex data structures.
 659  */
 660 static GLboolean
 661 init_attrib_groups(GLcontext *ctx)
 662 {
 663    assert(ctx);
 664
 665    /* Constants */
 666    _mesa_init_constants( ctx );
 667
 668    /* Extensions */
 669    _mesa_init_extensions( ctx );
 670
 671    /* Attribute Groups */
 672 #if FEATURE_accum
 673    _mesa_init_accum( ctx );
 674 #endif
 675 #if FEATURE_attrib_stack
 676    _mesa_init_attrib( ctx );
 677 #endif
 678    _mesa_init_buffer_objects( ctx );
 679    _mesa_init_color( ctx );
 680 #if FEATURE_colortable
 681    _mesa_init_colortables( ctx );
 682 #endif
 683    _mesa_init_current( ctx );
 684    _mesa_init_depth( ctx );
 685    _mesa_init_debug( ctx );
 686 #if FEATURE_dlist
 687    _mesa_init_display_list( ctx );
 688 #endif
 689 #if FEATURE_evaluators
 690    _mesa_init_eval( ctx );
 691 #endif
 692    _mesa_init_fbobjects( ctx );
 693 #if FEATURE_feedback
 694    _mesa_init_feedback( ctx );
 695 #else
 696    ctx->RenderMode = GL_RENDER;
 697 #endif
 698    _mesa_init_fog( ctx );
 699 #if FEATURE_histogram
 700    _mesa_init_histogram( ctx );
 701 #endif
 702    _mesa_init_hint( ctx );
 703    _mesa_init_line( ctx );
 704    _mesa_init_lighting( ctx );
 705    _mesa_init_matrix( ctx );
 706    _mesa_init_multisample( ctx );
 707    _mesa_init_pixel( ctx );
 708    _mesa_init_pixelstore( ctx );
 709    _mesa_init_point( ctx );
 710    _mesa_init_polygon( ctx );
 711    _mesa_init_program( ctx );
 712 #if FEATURE_ARB_occlusion_query
 713    _mesa_init_query( ctx );
 714 #endif
 715 #if FEATURE_drawpix
 716    _mesa_init_rastpos( ctx );
 717 #endif
 718    _mesa_init_scissor( ctx );
 719    _mesa_init_shader_state( ctx );
 720    _mesa_init_stencil( ctx );
 721    _mesa_init_transform( ctx );
 722    _mesa_init_varray( ctx );
 723    _mesa_init_viewport( ctx );
 724
 725    if (!_mesa_init_texture( ctx ))
 726       return GL_FALSE;
 727
 728 #if FEATURE_texture_s3tc
 729    _mesa_init_texture_s3tc( ctx );
 730 #endif
 731 #if FEATURE_texture_fxt1
 732    _mesa_init_texture_fxt1( ctx );
 733 #endif
 734
 735    /* Miscellaneous */
 736    ctx->NewState = _NEW_ALL;
 737    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
 738    ctx->varying_vp_inputs = ~0;
 739
 740    return GL_TRUE;
 741 }
 742
 743
 744 /**
 745  * Update default objects in a GL context with respect to shared state.
 746  *
 747  * \param ctx GL context.
 748  *
 749  * Removes references to old default objects, (texture objects, program
 750  * objects, etc.) and changes to reference those from the current shared
 751  * state.
 752  */
 753 static GLboolean
 754 update_default_objects(GLcontext *ctx)
 755 {
 756    assert(ctx);
 757
 758    _mesa_update_default_objects_program(ctx);
 759    _mesa_update_default_objects_texture(ctx);
 760    _mesa_update_default_objects_buffer_objects(ctx);
 761
 762    return GL_TRUE;
 763 }
 764
 765
 766 /**
 767  * This is the default function we plug into all dispatch table slots
 768  * This helps prevents a segfault when someone calls a GL function without
 769  * first checking if the extension's supported.
 770  */
 771 static int
 772 generic_nop(void)
 773 {
 774    _mesa_warning(NULL, "User called no-op dispatch function (an unsupported extension function?)");
 775    return 0;
 776 }
 777
 778
 779 /**
 780  * Allocate and initialize a new dispatch table.
 781  */
 782 static struct _glapi_table *
 783 alloc_dispatch_table(void)
 784 {
 785    /* Find the larger of Mesa's dispatch table and libGL's dispatch table.
 786     * In practice, this'll be the same for stand-alone Mesa.  But for DRI
 787     * Mesa we do this to accomodate different versions of libGL and various
 788     * DRI drivers.
 789     */
 790    GLint numEntries = MAX2(_glapi_get_dispatch_table_size(),
 791                            sizeof(struct _glapi_table) / sizeof(_glapi_proc));
 792    struct _glapi_table *table =
 793       (struct _glapi_table *) _mesa_malloc(numEntries * sizeof(_glapi_proc));
 794    if (table) {
 795       _glapi_proc *entry = (_glapi_proc *) table;
 796       GLint i;
 797       for (i = 0; i < numEntries; i++) {
 798          entry[i] = (_glapi_proc) generic_nop;
 799       }
 800    }
 801    return table;
 802 }
 803
 804
 805 /**
 806  * Initialize a GLcontext struct (rendering context).
 807  *
 808  * This includes allocating all the other structs and arrays which hang off of
 809  * the context by pointers.
 810  * Note that the driver needs to pass in its dd_function_table here since
 811  * we need to at least call driverFunctions->NewTextureObject to create the
 812  * default texture objects.
 813  *
 814  * Called by _mesa_create_context().
 815  *
 816  * Performs the imports and exports callback tables initialization, and
 817  * miscellaneous one-time initializations. If no shared context is supplied one
 818  * is allocated, and increase its reference count.  Setups the GL API dispatch
 819  * tables.  Initialize the TNL module. Sets the maximum Z buffer depth.
 820  * Finally queries the \c MESA_DEBUG and \c MESA_VERBOSE environment variables
 821  * for debug flags.
 822  *
 823  * \param ctx the context to initialize
 824  * \param visual describes the visual attributes for this context
 825  * \param share_list points to context to share textures, display lists,
 826  *        etc with, or NULL
 827  * \param driverFunctions table of device driver functions for this context
 828  *        to use
 829  * \param driverContext pointer to driver-specific context data
 830  */
 831 GLboolean
 832 _mesa_initialize_context(GLcontext *ctx,
 833                          const GLvisual *visual,
 834                          GLcontext *share_list,
 835                          const struct dd_function_table *driverFunctions,
 836                          void *driverContext)
 837 {
 838    struct gl_shared_state *shared;
 839
 840    /*ASSERT(driverContext);*/
 841    assert(driverFunctions->NewTextureObject);
 842    assert(driverFunctions->FreeTexImageData);
 843
 844    /* misc one-time initializations */
 845    one_time_init(ctx);
 846
 847    ctx->Visual = *visual;
 848    ctx->DrawBuffer = NULL;
 849    ctx->ReadBuffer = NULL;
 850    ctx->WinSysDrawBuffer = NULL;
 851    ctx->WinSysReadBuffer = NULL;
 852
 853    /* Plug in driver functions and context pointer here.
 854     * This is important because when we call alloc_shared_state() below
 855     * we'll call ctx->Driver.NewTextureObject() to create the default
 856     * textures.
 857     */
 858    ctx->Driver = *driverFunctions;
 859    ctx->DriverCtx = driverContext;
 860
 861    if (share_list) {
 862       /* share state with another context */
 863       shared = share_list->Shared;
 864    }
 865    else {
 866       /* allocate new, unshared state */
 867       shared = _mesa_alloc_shared_state(ctx);
 868       if (!shared)
 869          return GL_FALSE;
 870    }
 871
 872    _glthread_LOCK_MUTEX(shared->Mutex);
 873    ctx->Shared = shared;
 874    shared->RefCount++;
 875    _glthread_UNLOCK_MUTEX(shared->Mutex);
 876
 877    if (!init_attrib_groups( ctx )) {
 878       _mesa_free_shared_state(ctx, ctx->Shared);
 879       return GL_FALSE;
 880    }
 881
 882    /* setup the API dispatch tables */
 883    ctx->Exec = alloc_dispatch_table();
 884    ctx->Save = alloc_dispatch_table();
 885    if (!ctx->Exec || !ctx->Save) {
 886       _mesa_free_shared_state(ctx, ctx->Shared);
 887       if (ctx->Exec)
 888          _mesa_free(ctx->Exec);
 889    }
 890 #if FEATURE_dispatch
 891    _mesa_init_exec_table(ctx->Exec);
 892 #endif
 893    ctx->CurrentDispatch = ctx->Exec;
 894 #if FEATURE_dlist
 895    _mesa_init_dlist_table(ctx->Save);
 896    _mesa_install_save_vtxfmt( ctx, &ctx->ListState.ListVtxfmt );
 897 #endif
 898    /* Neutral tnl module stuff */
 899    _mesa_init_exec_vtxfmt( ctx );
 900    ctx->TnlModule.Current = NULL;
 901    ctx->TnlModule.SwapCount = 0;
 902
 903    ctx->FragmentProgram._MaintainTexEnvProgram
 904       = (_mesa_getenv("MESA_TEX_PROG") != NULL);
 905
 906    ctx->VertexProgram._MaintainTnlProgram
 907       = (_mesa_getenv("MESA_TNL_PROG") != NULL);
 908    if (ctx->VertexProgram._MaintainTnlProgram) {
 909       /* this is required... */
 910       ctx->FragmentProgram._MaintainTexEnvProgram = GL_TRUE;
 911    }
 912
 913 #ifdef FEATURE_extra_context_init
 914    _mesa_initialize_context_extra(ctx);
 915 #endif
 916
 917    ctx->FirstTimeCurrent = GL_TRUE;
 918
 919    return GL_TRUE;
 920 }
 921
 922
 923 /**
 924  * Allocate and initialize a GLcontext structure.
 925  * Note that the driver needs to pass in its dd_function_table here since
 926  * we need to at least call driverFunctions->NewTextureObject to initialize
 927  * the rendering context.
 928  *
 929  * \param visual a GLvisual pointer (we copy the struct contents)
 930  * \param share_list another context to share display lists with or NULL
 931  * \param driverFunctions points to the dd_function_table into which the
 932  *        driver has plugged in all its special functions.
 933  * \param driverContext points to the device driver's private context state
 934  *
 935  * \return pointer to a new __GLcontextRec or NULL if error.
 936  */
 937 GLcontext *
 938 _mesa_create_context(const GLvisual *visual,
 939                      GLcontext *share_list,
 940                      const struct dd_function_table *driverFunctions,
 941                      void *driverContext)
 942 {
 943    GLcontext *ctx;
 944
 945    ASSERT(visual);
 946    /*ASSERT(driverContext);*/
 947
 948    ctx = (GLcontext *) _mesa_calloc(sizeof(GLcontext));
 949    if (!ctx)
 950       return NULL;
 951
 952    if (_mesa_initialize_context(ctx, visual, share_list,
 953                                 driverFunctions, driverContext)) {
 954       return ctx;
 955    }
 956    else {
 957       _mesa_free(ctx);
 958       return NULL;
 959    }
 960 }
 961
 962
 963 /**
 964  * Free the data associated with the given context.
 965  *
 966  * But doesn't free the GLcontext struct itself.
 967  *
 968  * \sa _mesa_initialize_context() and init_attrib_groups().
 969  */
 970 void
 971 _mesa_free_context_data( GLcontext *ctx )
 972 {
 973    GLint RefCount;
 974
 975    if (!_mesa_get_current_context()){
 976       /* No current context, but we may need one in order to delete
 977        * texture objs, etc.  So temporarily bind the context now.
 978        */
 979       _mesa_make_current(ctx, NULL, NULL);
 980    }
 981
 982    /* unreference WinSysDraw/Read buffers */
 983    _mesa_reference_framebuffer(&ctx->WinSysDrawBuffer, NULL);
 984    _mesa_reference_framebuffer(&ctx->WinSysReadBuffer, NULL);
 985    _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
 986    _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
 987
 988    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
 989    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._Current, NULL);
 990    _mesa_reference_vertprog(ctx, &ctx->VertexProgram._TnlProgram, NULL);
 991
 992    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
 993    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._Current, NULL);
 994    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram._TexEnvProgram, NULL);
 995
 996 #if FEATURE_attrib_stack
 997    _mesa_free_attrib_data(ctx);
 998 #endif
 999    _mesa_free_lighting_data( ctx );
1000 #if FEATURE_evaluators
1001    _mesa_free_eval_data( ctx );
1002 #endif
1003    _mesa_free_texture_data( ctx );
1004    _mesa_free_matrix_data( ctx );
1005    _mesa_free_viewport_data( ctx );
1006 #if FEATURE_colortable
1007    _mesa_free_colortables_data( ctx );
1008 #endif
1009    _mesa_free_program_data(ctx);
1010    _mesa_free_shader_state(ctx);
1011 #if FEATURE_ARB_occlusion_query
1012    _mesa_free_query_data(ctx);
1013 #endif
1014    _mesa_free_varray_data(ctx);
1015
1016    _mesa_delete_array_object(ctx, ctx->Array.DefaultArrayObj);
1017
1018 #if FEATURE_ARB_pixel_buffer_object
1019    _mesa_reference_buffer_object(ctx, &ctx->Pack.BufferObj, NULL);
1020    _mesa_reference_buffer_object(ctx, &ctx->Unpack.BufferObj, NULL);
1021 #endif
1022
1023 #if FEATURE_ARB_vertex_buffer_object
1024    _mesa_reference_buffer_object(ctx, &ctx->Array.ArrayBufferObj, NULL);
1025    _mesa_reference_buffer_object(ctx, &ctx->Array.ElementArrayBufferObj, NULL);
1026 #endif
1027
1028    /* free dispatch tables */
1029    _mesa_free(ctx->Exec);
1030    _mesa_free(ctx->Save);
1031
1032    /* Shared context state (display lists, textures, etc) */
1033    _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1034    RefCount = --ctx->Shared->RefCount;
1035    _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1036    assert(RefCount >= 0);
1037    if (RefCount == 0) {
1038       /* free shared state */
1039       _mesa_free_shared_state( ctx, ctx->Shared );
1040    }
1041
1042    if (ctx->Extensions.String)
1043       _mesa_free((void *) ctx->Extensions.String);
1044
1045    /* unbind the context if it's currently bound */
1046    if (ctx == _mesa_get_current_context()) {
1047       _mesa_make_current(NULL, NULL, NULL);
1048    }
1049 }
1050
1051
1052 /**
1053  * Destroy a GLcontext structure.
1054  *
1055  * \param ctx GL context.
1056  *
1057  * Calls _mesa_free_context_data() and frees the GLcontext structure itself.
1058  */
1059 void
1060 _mesa_destroy_context( GLcontext *ctx )
1061 {
1062    if (ctx) {
1063       _mesa_free_context_data(ctx);
1064       _mesa_free( (void *) ctx );
1065    }
1066 }
1067
1068
1069 #if _HAVE_FULL_GL
1070 /**
1071  * Copy attribute groups from one context to another.
1072  *
1073  * \param src source context
1074  * \param dst destination context
1075  * \param mask bitwise OR of GL_*_BIT flags
1076  *
1077  * According to the bits specified in \p mask, copies the corresponding
1078  * attributes from \p src into \p dst.  For many of the attributes a simple \c
1079  * memcpy is not enough due to the existence of internal pointers in their data
1080  * structures.
1081  */
1082 void
1083 _mesa_copy_context( const GLcontext *src, GLcontext *dst, GLuint mask )
1084 {
1085    if (mask & GL_ACCUM_BUFFER_BIT) {
1086       /* OK to memcpy */
1087       dst->Accum = src->Accum;
1088    }
1089    if (mask & GL_COLOR_BUFFER_BIT) {
1090       /* OK to memcpy */
1091       dst->Color = src->Color;
1092    }
1093    if (mask & GL_CURRENT_BIT) {
1094       /* OK to memcpy */
1095       dst->Current = src->Current;
1096    }
1097    if (mask & GL_DEPTH_BUFFER_BIT) {
1098       /* OK to memcpy */
1099       dst->Depth = src->Depth;
1100    }
1101    if (mask & GL_ENABLE_BIT) {
1102       /* no op */
1103    }
1104    if (mask & GL_EVAL_BIT) {
1105       /* OK to memcpy */
1106       dst->Eval = src->Eval;
1107    }
1108    if (mask & GL_FOG_BIT) {
1109       /* OK to memcpy */
1110       dst->Fog = src->Fog;
1111    }
1112    if (mask & GL_HINT_BIT) {
1113       /* OK to memcpy */
1114       dst->Hint = src->Hint;
1115    }
1116    if (mask & GL_LIGHTING_BIT) {
1117       GLuint i;
1118       /* begin with memcpy */
1119       dst->Light = src->Light;
1120       /* fixup linked lists to prevent pointer insanity */
1121       make_empty_list( &(dst->Light.EnabledList) );
1122       for (i = 0; i < MAX_LIGHTS; i++) {
1123          if (dst->Light.Light[i].Enabled) {
1124             insert_at_tail(&(dst->Light.EnabledList), &(dst->Light.Light[i]));
1125          }
1126       }
1127    }
1128    if (mask & GL_LINE_BIT) {
1129       /* OK to memcpy */
1130       dst->Line = src->Line;
1131    }
1132    if (mask & GL_LIST_BIT) {
1133       /* OK to memcpy */
1134       dst->List = src->List;
1135    }
1136    if (mask & GL_PIXEL_MODE_BIT) {
1137       /* OK to memcpy */
1138       dst->Pixel = src->Pixel;
1139    }
1140    if (mask & GL_POINT_BIT) {
1141       /* OK to memcpy */
1142       dst->Point = src->Point;
1143    }
1144    if (mask & GL_POLYGON_BIT) {
1145       /* OK to memcpy */
1146       dst->Polygon = src->Polygon;
1147    }
1148    if (mask & GL_POLYGON_STIPPLE_BIT) {
1149       /* Use loop instead of MEMCPY due to problem with Portland Group's
1150        * C compiler.  Reported by John Stone.
1151        */
1152       GLuint i;
1153       for (i = 0; i < 32; i++) {
1154          dst->PolygonStipple[i] = src->PolygonStipple[i];
1155       }
1156    }
1157    if (mask & GL_SCISSOR_BIT) {
1158       /* OK to memcpy */
1159       dst->Scissor = src->Scissor;
1160    }
1161    if (mask & GL_STENCIL_BUFFER_BIT) {
1162       /* OK to memcpy */
1163       dst->Stencil = src->Stencil;
1164    }
1165    if (mask & GL_TEXTURE_BIT) {
1166       /* Cannot memcpy because of pointers */
1167       _mesa_copy_texture_state(src, dst);
1168    }
1169    if (mask & GL_TRANSFORM_BIT) {
1170       /* OK to memcpy */
1171       dst->Transform = src->Transform;
1172    }
1173    if (mask & GL_VIEWPORT_BIT) {
1174       /* Cannot use memcpy, because of pointers in GLmatrix _WindowMap */
1175       dst->Viewport.X = src->Viewport.X;
1176       dst->Viewport.Y = src->Viewport.Y;
1177       dst->Viewport.Width = src->Viewport.Width;
1178       dst->Viewport.Height = src->Viewport.Height;
1179       dst->Viewport.Near = src->Viewport.Near;
1180       dst->Viewport.Far = src->Viewport.Far;
1181       _math_matrix_copy(&dst->Viewport._WindowMap, &src->Viewport._WindowMap);
1182    }
1183
1184    /* XXX FIXME:  Call callbacks?
1185     */
1186    dst->NewState = _NEW_ALL;
1187 }
1188 #endif
1189
1190
1191 /**
1192  * Check if the given context can render into the given framebuffer
1193  * by checking visual attributes.
1194  *
1195  * Most of these tests could go away because Mesa is now pretty flexible
1196  * in terms of mixing rendering contexts with framebuffers.  As long
1197  * as RGB vs. CI mode agree, we're probably good.
1198  *
1199  * \return GL_TRUE if compatible, GL_FALSE otherwise.
1200  */
1201 static GLboolean
1202 check_compatible(const GLcontext *ctx, const GLframebuffer *buffer)
1203 {
1204    const GLvisual *ctxvis = &ctx->Visual;
1205    const GLvisual *bufvis = &buffer->Visual;
1206
1207    if (ctxvis == bufvis)
1208       return GL_TRUE;
1209
1210    if (ctxvis->rgbMode != bufvis->rgbMode)
1211       return GL_FALSE;
1212 #if 0
1213    /* disabling this fixes the fgl_glxgears pbuffer demo */
1214    if (ctxvis->doubleBufferMode && !bufvis->doubleBufferMode)
1215       return GL_FALSE;
1216 #endif
1217    if (ctxvis->stereoMode && !bufvis->stereoMode)
1218       return GL_FALSE;
1219    if (ctxvis->haveAccumBuffer && !bufvis->haveAccumBuffer)
1220       return GL_FALSE;
1221    if (ctxvis->haveDepthBuffer && !bufvis->haveDepthBuffer)
1222       return GL_FALSE;
1223    if (ctxvis->haveStencilBuffer && !bufvis->haveStencilBuffer)
1224       return GL_FALSE;
1225    if (ctxvis->redMask && ctxvis->redMask != bufvis->redMask)
1226       return GL_FALSE;
1227    if (ctxvis->greenMask && ctxvis->greenMask != bufvis->greenMask)
1228       return GL_FALSE;
1229    if (ctxvis->blueMask && ctxvis->blueMask != bufvis->blueMask)
1230       return GL_FALSE;
1231 #if 0
1232    /* disabled (see bug 11161) */
1233    if (ctxvis->depthBits && ctxvis->depthBits != bufvis->depthBits)
1234       return GL_FALSE;
1235 #endif
1236    if (ctxvis->stencilBits && ctxvis->stencilBits != bufvis->stencilBits)
1237       return GL_FALSE;
1238
1239    return GL_TRUE;
1240 }
1241
1242
1243 /**
1244  * Do one-time initialization for the given framebuffer.  Specifically,
1245  * ask the driver for the window's current size and update the framebuffer
1246  * object to match.
1247  * Really, the device driver should totally take care of this.
1248  */
1249 static void
1250 initialize_framebuffer_size(GLcontext *ctx, GLframebuffer *fb)
1251 {
1252    GLuint width, height;
1253    if (ctx->Driver.GetBufferSize) {
1254       ctx->Driver.GetBufferSize(fb, &width, &height);
1255       if (ctx->Driver.ResizeBuffers)
1256          ctx->Driver.ResizeBuffers(ctx, fb, width, height);
1257       fb->Initialized = GL_TRUE;
1258    }
1259 }
1260
1261
1262 /**
1263  * Check if the viewport/scissor size has not yet been initialized.
1264  * Initialize the size if the given width and height are non-zero.
1265  */
1266 void
1267 _mesa_check_init_viewport(GLcontext *ctx, GLuint width, GLuint height)
1268 {
1269    if (!ctx->ViewportInitialized && width > 0 && height > 0) {
1270       /* Note: set flag here, before calling _mesa_set_viewport(), to prevent
1271        * potential infinite recursion.
1272        */
1273       ctx->ViewportInitialized = GL_TRUE;
1274       _mesa_set_viewport(ctx, 0, 0, width, height);
1275       _mesa_set_scissor(ctx, 0, 0, width, height);
1276    }
1277 }
1278
1279
1280 /**
1281  * Bind the given context to the given drawBuffer and readBuffer and
1282  * make it the current context for the calling thread.
1283  * We'll render into the drawBuffer and read pixels from the
1284  * readBuffer (i.e. glRead/CopyPixels, glCopyTexImage, etc).
1285  *
1286  * We check that the context's and framebuffer's visuals are compatible
1287  * and return immediately if they're not.
1288  *
1289  * \param newCtx  the new GL context. If NULL then there will be no current GL
1290  *                context.
1291  * \param drawBuffer  the drawing framebuffer
1292  * \param readBuffer  the reading framebuffer
1293  */
1294 GLboolean
1295 _mesa_make_current( GLcontext *newCtx, GLframebuffer *drawBuffer,
1296                     GLframebuffer *readBuffer )
1297 {
1298    if (MESA_VERBOSE & VERBOSE_API)
1299       _mesa_debug(newCtx, "_mesa_make_current()\n");
1300
1301    /* Check that the context's and framebuffer's visuals are compatible.
1302     */
1303    if (newCtx && drawBuffer && newCtx->WinSysDrawBuffer != drawBuffer) {
1304       if (!check_compatible(newCtx, drawBuffer)) {
1305          _mesa_warning(newCtx,
1306               "MakeCurrent: incompatible visuals for context and drawbuffer");
1307          return GL_FALSE;
1308       }
1309    }
1310    if (newCtx && readBuffer && newCtx->WinSysReadBuffer != readBuffer) {
1311       if (!check_compatible(newCtx, readBuffer)) {
1312          _mesa_warning(newCtx,
1313               "MakeCurrent: incompatible visuals for context and readbuffer");
1314          return GL_FALSE;
1315       }
1316    }
1317
1318    /* We used to call _glapi_check_multithread() here.  Now do it in drivers */
1319    _glapi_set_context((void *) newCtx);
1320    ASSERT(_mesa_get_current_context() == newCtx);
1321
1322    if (!newCtx) {
1323       _glapi_set_dispatch(NULL);  /* none current */
1324    }
1325    else {
1326       _glapi_set_dispatch(newCtx->CurrentDispatch);
1327
1328       if (drawBuffer && readBuffer) {
1329          /* TODO: check if newCtx and buffer's visual match??? */
1330
1331          ASSERT(drawBuffer->Name == 0);
1332          ASSERT(readBuffer->Name == 0);
1333          _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, drawBuffer);
1334          _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, readBuffer);
1335
1336          /*
1337           * Only set the context's Draw/ReadBuffer fields if they're NULL
1338           * or not bound to a user-created FBO.
1339           */
1340          if (!newCtx->DrawBuffer || newCtx->DrawBuffer->Name == 0) {
1341             /* KW: merge conflict here, revisit.
1342              */
1343             /* fix up the fb fields - these will end up wrong otherwise
1344              * if the DRIdrawable changes, and everything relies on them.
1345              * This is a bit messy (same as needed in _mesa_BindFramebufferEXT)
1346              */
1347             unsigned int i;
1348             GLenum buffers[MAX_DRAW_BUFFERS];
1349
1350             _mesa_reference_framebuffer(&newCtx->DrawBuffer, drawBuffer);
1351
1352             for(i = 0; i < newCtx->Const.MaxDrawBuffers; i++) {
1353                buffers[i] = newCtx->Color.DrawBuffer[i];
1354             }
1355
1356             _mesa_drawbuffers(newCtx, newCtx->Const.MaxDrawBuffers, buffers, NULL);
1357          }
1358          if (!newCtx->ReadBuffer || newCtx->ReadBuffer->Name == 0) {
1359             _mesa_reference_framebuffer(&newCtx->ReadBuffer, readBuffer);
1360          }
1361
1362          /* XXX only set this flag if we're really changing the draw/read
1363           * framebuffer bindings.
1364           */
1365          newCtx->NewState |= _NEW_BUFFERS;
1366
1367 #if 1
1368          /* We want to get rid of these lines: */
1369
1370 #if _HAVE_FULL_GL
1371          if (!drawBuffer->Initialized) {
1372             initialize_framebuffer_size(newCtx, drawBuffer);
1373          }
1374          if (readBuffer != drawBuffer && !readBuffer->Initialized) {
1375             initialize_framebuffer_size(newCtx, readBuffer);
1376          }
1377
1378          _mesa_resizebuffers(newCtx);
1379 #endif
1380
1381 #else
1382          /* We want the drawBuffer and readBuffer to be initialized by
1383           * the driver.
1384           * This generally means the Width and Height match the actual
1385           * window size and the renderbuffers (both hardware and software
1386           * based) are allocated to match.  The later can generally be
1387           * done with a call to _mesa_resize_framebuffer().
1388           *
1389           * It's theoretically possible for a buffer to have zero width
1390           * or height, but for now, assert check that the driver did what's
1391           * expected of it.
1392           */
1393          ASSERT(drawBuffer->Width > 0);
1394          ASSERT(drawBuffer->Height > 0);
1395 #endif
1396
1397          if (drawBuffer) {
1398             _mesa_check_init_viewport(newCtx,
1399                                       drawBuffer->Width, drawBuffer->Height);
1400          }
1401       }
1402
1403       if (newCtx->FirstTimeCurrent) {
1404          check_context_limits(newCtx);
1405
1406          /* We can use this to help debug user's problems.  Tell them to set
1407           * the MESA_INFO env variable before running their app.  Then the
1408           * first time each context is made current we'll print some useful
1409           * information.
1410           */
1411          if (_mesa_getenv("MESA_INFO")) {
1412             _mesa_print_info();
1413          }
1414
1415          newCtx->FirstTimeCurrent = GL_FALSE;
1416       }
1417    }
1418
1419    return GL_TRUE;
1420 }
1421
1422
1423 /**
1424  * Make context 'ctx' share the display lists, textures and programs
1425  * that are associated with 'ctxToShare'.
1426  * Any display lists, textures or programs associated with 'ctx' will
1427  * be deleted if nobody else is sharing them.
1428  */
1429 GLboolean
1430 _mesa_share_state(GLcontext *ctx, GLcontext *ctxToShare)
1431 {
1432    if (ctx && ctxToShare && ctx->Shared && ctxToShare->Shared) {
1433       struct gl_shared_state *oldSharedState = ctx->Shared;
1434       GLint RefCount;
1435
1436       ctx->Shared = ctxToShare->Shared;
1437
1438       _glthread_LOCK_MUTEX(ctx->Shared->Mutex);
1439       ctx->Shared->RefCount++;
1440       _glthread_UNLOCK_MUTEX(ctx->Shared->Mutex);
1441
1442       update_default_objects(ctx);
1443
1444       _glthread_LOCK_MUTEX(oldSharedState->Mutex);
1445       RefCount = --oldSharedState->RefCount;
1446       _glthread_UNLOCK_MUTEX(oldSharedState->Mutex);
1447
1448       if (RefCount == 0) {
1449          _mesa_free_shared_state(ctx, oldSharedState);
1450       }
1451
1452       return GL_TRUE;
1453    }
1454    else {
1455       return GL_FALSE;
1456    }
1457 }
1458
1459
1460
1461 /**
1462  * \return pointer to the current GL context for this thread.
1463  *
1464  * Calls _glapi_get_context(). This isn't the fastest way to get the current
1465  * context.  If you need speed, see the #GET_CURRENT_CONTEXT macro in
1466  * context.h.
1467  */
1468 GLcontext *
1469 _mesa_get_current_context( void )
1470 {
1471    return (GLcontext *) _glapi_get_context();
1472 }
1473
1474
1475 /**
1476  * Get context's current API dispatch table.
1477  *
1478  * It'll either be the immediate-mode execute dispatcher or the display list
1479  * compile dispatcher.
1480  *
1481  * \param ctx GL context.
1482  *
1483  * \return pointer to dispatch_table.
1484  *
1485  * Simply returns __GLcontextRec::CurrentDispatch.
1486  */
1487 struct _glapi_table *
1488 _mesa_get_dispatch(GLcontext *ctx)
1489 {
1490    return ctx->CurrentDispatch;
1491 }
1492
1493 /*@}*/
1494
1495
1496 /**********************************************************************/
1497 /** \name Miscellaneous functions                                     */
1498 /**********************************************************************/
1499 /*@{*/
1500
1501 /**
1502  * Record an error.
1503  *
1504  * \param ctx GL context.
1505  * \param error error code.
1506  *
1507  * Records the given error code and call the driver's dd_function_table::Error
1508  * function if defined.
1509  *
1510  * \sa
1511  * This is called via _mesa_error().
1512  */
1513 void
1514 _mesa_record_error(GLcontext *ctx, GLenum error)
1515 {
1516    if (!ctx)
1517       return;
1518
1519    if (ctx->ErrorValue == GL_NO_ERROR) {
1520       ctx->ErrorValue = error;
1521    }
1522
1523    /* Call device driver's error handler, if any.  This is used on the Mac. */
1524    if (ctx->Driver.Error) {
1525       ctx->Driver.Error(ctx);
1526    }
1527 }
1528
1529
1530 /**
1531  * Execute glFinish().
1532  *
1533  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1534  * dd_function_table::Finish driver callback, if not NULL.
1535  */
1536 void GLAPIENTRY
1537 _mesa_Finish(void)
1538 {
1539    GET_CURRENT_CONTEXT(ctx);
1540    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1541    FLUSH_CURRENT( ctx, 0 );
1542    if (ctx->Driver.Finish) {
1543       ctx->Driver.Finish(ctx);
1544    }
1545 }
1546
1547
1548 /**
1549  * Execute glFlush().
1550  *
1551  * Calls the #ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH macro and the
1552  * dd_function_table::Flush driver callback, if not NULL.
1553  */
1554 void GLAPIENTRY
1555 _mesa_Flush(void)
1556 {
1557    GET_CURRENT_CONTEXT(ctx);
1558    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
1559    FLUSH_CURRENT( ctx, 0 );
1560    if (ctx->Driver.Flush) {
1561       ctx->Driver.Flush(ctx);
1562    }
1563 }
1564
1565
1566 /**
1567  * Set mvp_with_dp4 flag.  If a driver has a preference for DP4 over
1568  * MUL/MAD, or vice versa, call this function to register that.
1569  * Otherwise we default to MUL/MAD.
1570  */
1571 void
1572 _mesa_set_mvp_with_dp4( GLcontext *ctx,
1573                         GLboolean flag )
1574 {
1575    ctx->mvp_with_dp4 = flag;
1576 }
1577
1578
1579 /*@}*/