src/mesa/main/formatquery.c

   1 /*
   2  * Copyright © 2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 #include "mtypes.h"
  25 #include "context.h"
  26 #include "glformats.h"
  27 #include "macros.h"
  28 #include "enums.h"
  29 #include "fbobject.h"
  30 #include "formatquery.h"
  31 #include "teximage.h"
  32
  33 /* Handles the cases where either ARB_internalformat_query or
  34  * ARB_internalformat_query2 have to return an error.
  35  */
  36 static bool
  37 _legal_parameters(struct gl_context *ctx, GLenum target, GLenum internalformat,
  38                   GLenum pname, GLsizei bufSize, GLint *params)
  39
  40 {
  41    bool query2 = _mesa_has_ARB_internalformat_query2(ctx);
  42
  43    /* The ARB_internalformat_query2 spec says:
  44     *
  45     *    "The INVALID_ENUM error is generated if the <target> parameter to
  46     *    GetInternalformati*v is not one of the targets listed in Table 6.xx.
  47     */
  48    switch(target){
  49    case GL_TEXTURE_1D:
  50    case GL_TEXTURE_1D_ARRAY:
  51    case GL_TEXTURE_2D:
  52    case GL_TEXTURE_2D_ARRAY:
  53    case GL_TEXTURE_3D:
  54    case GL_TEXTURE_CUBE_MAP:
  55    case GL_TEXTURE_CUBE_MAP_ARRAY:
  56    case GL_TEXTURE_RECTANGLE:
  57    case GL_TEXTURE_BUFFER:
  58       if (!query2) {
  59          /* The ARB_internalformat_query spec says:
  60           *
  61           *     "If the <target> parameter to GetInternalformativ is not one of
  62           *      TEXTURE_2D_MULTISAMPLE, TEXTURE_2D_MULTISAMPLE_ARRAY
  63           *      or RENDERBUFFER then an INVALID_ENUM error is generated.
  64           */
  65          _mesa_error(ctx, GL_INVALID_ENUM,
  66                      "glGetInternalformativ(target=%s)",
  67                      _mesa_enum_to_string(target));
  68
  69          return false;
  70       }
  71       break;
  72
  73    case GL_RENDERBUFFER:
  74       break;
  75
  76    case GL_TEXTURE_2D_MULTISAMPLE:
  77    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
  78       /* The non-existence of ARB_texture_multisample is treated in
  79        * ARB_internalformat_query implementation like an error.
  80        */
  81       if (!query2 &&
  82           !(_mesa_has_ARB_texture_multisample(ctx) || _mesa_is_gles31(ctx))) {
  83          _mesa_error(ctx, GL_INVALID_ENUM,
  84                      "glGetInternalformativ(target=%s)",
  85                      _mesa_enum_to_string(target));
  86
  87          return false;
  88       }
  89       break;
  90
  91    default:
  92       _mesa_error(ctx, GL_INVALID_ENUM,
  93                   "glGetInternalformativ(target=%s)",
  94                   _mesa_enum_to_string(target));
  95       return false;
  96    }
  97
  98
  99    /* The ARB_internalformat_query2 spec says:
 100     *
 101     *     "The INVALID_ENUM error is generated if the <pname> parameter is
 102     *     not one of the listed possibilities.
 103     */
 104    switch(pname){
 105    case GL_SAMPLES:
 106    case GL_NUM_SAMPLE_COUNTS:
 107       break;
 108
 109    case GL_SRGB_DECODE_ARB:
 110       /* The ARB_internalformat_query2 spec says:
 111        *
 112        *     "If ARB_texture_sRGB_decode or EXT_texture_sRGB_decode or
 113        *     equivalent functionality is not supported, queries for the
 114        *     SRGB_DECODE_ARB <pname> set the INVALID_ENUM error.
 115        */
 116       if (!_mesa_has_EXT_texture_sRGB_decode(ctx)) {
 117          _mesa_error(ctx, GL_INVALID_ENUM,
 118                      "glGetInternalformativ(pname=%s)",
 119                      _mesa_enum_to_string(pname));
 120          return false;
 121       }
 122       /* fallthrough */
 123    case GL_INTERNALFORMAT_SUPPORTED:
 124    case GL_INTERNALFORMAT_PREFERRED:
 125    case GL_INTERNALFORMAT_RED_SIZE:
 126    case GL_INTERNALFORMAT_GREEN_SIZE:
 127    case GL_INTERNALFORMAT_BLUE_SIZE:
 128    case GL_INTERNALFORMAT_ALPHA_SIZE:
 129    case GL_INTERNALFORMAT_DEPTH_SIZE:
 130    case GL_INTERNALFORMAT_STENCIL_SIZE:
 131    case GL_INTERNALFORMAT_SHARED_SIZE:
 132    case GL_INTERNALFORMAT_RED_TYPE:
 133    case GL_INTERNALFORMAT_GREEN_TYPE:
 134    case GL_INTERNALFORMAT_BLUE_TYPE:
 135    case GL_INTERNALFORMAT_ALPHA_TYPE:
 136    case GL_INTERNALFORMAT_DEPTH_TYPE:
 137    case GL_INTERNALFORMAT_STENCIL_TYPE:
 138    case GL_MAX_WIDTH:
 139    case GL_MAX_HEIGHT:
 140    case GL_MAX_DEPTH:
 141    case GL_MAX_LAYERS:
 142    case GL_MAX_COMBINED_DIMENSIONS:
 143    case GL_COLOR_COMPONENTS:
 144    case GL_DEPTH_COMPONENTS:
 145    case GL_STENCIL_COMPONENTS:
 146    case GL_COLOR_RENDERABLE:
 147    case GL_DEPTH_RENDERABLE:
 148    case GL_STENCIL_RENDERABLE:
 149    case GL_FRAMEBUFFER_RENDERABLE:
 150    case GL_FRAMEBUFFER_RENDERABLE_LAYERED:
 151    case GL_FRAMEBUFFER_BLEND:
 152    case GL_READ_PIXELS:
 153    case GL_READ_PIXELS_FORMAT:
 154    case GL_READ_PIXELS_TYPE:
 155    case GL_TEXTURE_IMAGE_FORMAT:
 156    case GL_TEXTURE_IMAGE_TYPE:
 157    case GL_GET_TEXTURE_IMAGE_FORMAT:
 158    case GL_GET_TEXTURE_IMAGE_TYPE:
 159    case GL_MIPMAP:
 160    case GL_MANUAL_GENERATE_MIPMAP:
 161    case GL_AUTO_GENERATE_MIPMAP:
 162    case GL_COLOR_ENCODING:
 163    case GL_SRGB_READ:
 164    case GL_SRGB_WRITE:
 165    case GL_FILTER:
 166    case GL_VERTEX_TEXTURE:
 167    case GL_TESS_CONTROL_TEXTURE:
 168    case GL_TESS_EVALUATION_TEXTURE:
 169    case GL_GEOMETRY_TEXTURE:
 170    case GL_FRAGMENT_TEXTURE:
 171    case GL_COMPUTE_TEXTURE:
 172    case GL_TEXTURE_SHADOW:
 173    case GL_TEXTURE_GATHER:
 174    case GL_TEXTURE_GATHER_SHADOW:
 175    case GL_SHADER_IMAGE_LOAD:
 176    case GL_SHADER_IMAGE_STORE:
 177    case GL_SHADER_IMAGE_ATOMIC:
 178    case GL_IMAGE_TEXEL_SIZE:
 179    case GL_IMAGE_COMPATIBILITY_CLASS:
 180    case GL_IMAGE_PIXEL_FORMAT:
 181    case GL_IMAGE_PIXEL_TYPE:
 182    case GL_IMAGE_FORMAT_COMPATIBILITY_TYPE:
 183    case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST:
 184    case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST:
 185    case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE:
 186    case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE:
 187    case GL_TEXTURE_COMPRESSED:
 188    case GL_TEXTURE_COMPRESSED_BLOCK_WIDTH:
 189    case GL_TEXTURE_COMPRESSED_BLOCK_HEIGHT:
 190    case GL_TEXTURE_COMPRESSED_BLOCK_SIZE:
 191    case GL_CLEAR_BUFFER:
 192    case GL_TEXTURE_VIEW:
 193    case GL_VIEW_COMPATIBILITY_CLASS:
 194       /* The ARB_internalformat_query spec says:
 195        *
 196        *     "If the <pname> parameter to GetInternalformativ is not SAMPLES
 197        *     or NUM_SAMPLE_COUNTS, then an INVALID_ENUM error is generated."
 198        */
 199       if (!query2) {
 200          _mesa_error(ctx, GL_INVALID_ENUM,
 201                      "glGetInternalformativ(pname=%s)",
 202                      _mesa_enum_to_string(pname));
 203
 204          return false;
 205       }
 206       break;
 207
 208    default:
 209       _mesa_error(ctx, GL_INVALID_ENUM,
 210                   "glGetInternalformativ(pname=%s)",
 211                   _mesa_enum_to_string(pname));
 212       return false;
 213    }
 214
 215    /* The ARB_internalformat_query spec says:
 216     *
 217     *     "If the <bufSize> parameter to GetInternalformativ is negative, then
 218     *     an INVALID_VALUE error is generated."
 219     *
 220     * Nothing is said in ARB_internalformat_query2 but we assume the same.
 221     */
 222    if (bufSize < 0) {
 223       _mesa_error(ctx, GL_INVALID_VALUE,
 224                   "glGetInternalformativ(target=%s)",
 225                   _mesa_enum_to_string(target));
 226       return false;
 227    }
 228
 229    /* The ARB_internalformat_query spec says:
 230     *
 231     *     "If the <internalformat> parameter to GetInternalformativ is not
 232     *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
 233     *     generated."
 234     *
 235     * Page 243 of the GLES 3.0.4 spec says this for GetInternalformativ:
 236     *
 237     *     "internalformat must be color-renderable, depth-renderable or
 238     *     stencilrenderable (as defined in section 4.4.4)."
 239     *
 240     * Section 4.4.4 on page 212 of the same spec says:
 241     *
 242     *     "An internal format is color-renderable if it is one of the
 243     *     formats from table 3.13 noted as color-renderable or if it
 244     *     is unsized format RGBA or RGB."
 245     *
 246     * Therefore, we must accept GL_RGB and GL_RGBA here.
 247     */
 248    if (!query2 &&
 249        internalformat != GL_RGB && internalformat != GL_RGBA &&
 250        _mesa_base_fbo_format(ctx, internalformat) == 0) {
 251       _mesa_error(ctx, GL_INVALID_ENUM,
 252                   "glGetInternalformativ(internalformat=%s)",
 253                   _mesa_enum_to_string(internalformat));
 254       return false;
 255    }
 256
 257    return true;
 258 }
 259
 260 /* Sets the appropriate "unsupported" response as defined by the
 261  * ARB_internalformat_query2 spec for each each <pname>.
 262  */
 263 static void
 264 _set_default_response(GLenum pname, GLint buffer[16])
 265 {
 266    /* The ARB_internalformat_query2 defines which is the reponse best
 267     * representing "not supported" or "not applicable" for each <pname>.
 268     *
 269     *     " In general:
 270     *          - size- or count-based queries will return zero,
 271     *          - support-, format- or type-based queries will return NONE,
 272     *          - boolean-based queries will return FALSE, and
 273     *          - list-based queries return no entries."
 274     */
 275    switch(pname) {
 276    case GL_SAMPLES:
 277       break;
 278
 279    case GL_MAX_COMBINED_DIMENSIONS:
 280    case GL_NUM_SAMPLE_COUNTS:
 281    case GL_INTERNALFORMAT_RED_SIZE:
 282    case GL_INTERNALFORMAT_GREEN_SIZE:
 283    case GL_INTERNALFORMAT_BLUE_SIZE:
 284    case GL_INTERNALFORMAT_ALPHA_SIZE:
 285    case GL_INTERNALFORMAT_DEPTH_SIZE:
 286    case GL_INTERNALFORMAT_STENCIL_SIZE:
 287    case GL_INTERNALFORMAT_SHARED_SIZE:
 288    case GL_MAX_WIDTH:
 289    case GL_MAX_HEIGHT:
 290    case GL_MAX_DEPTH:
 291    case GL_MAX_LAYERS:
 292    case GL_IMAGE_TEXEL_SIZE:
 293    case GL_TEXTURE_COMPRESSED_BLOCK_WIDTH:
 294    case GL_TEXTURE_COMPRESSED_BLOCK_HEIGHT:
 295    case GL_TEXTURE_COMPRESSED_BLOCK_SIZE:
 296       buffer[0] = 0;
 297       break;
 298
 299    case GL_INTERNALFORMAT_PREFERRED:
 300    case GL_INTERNALFORMAT_RED_TYPE:
 301    case GL_INTERNALFORMAT_GREEN_TYPE:
 302    case GL_INTERNALFORMAT_BLUE_TYPE:
 303    case GL_INTERNALFORMAT_ALPHA_TYPE:
 304    case GL_INTERNALFORMAT_DEPTH_TYPE:
 305    case GL_INTERNALFORMAT_STENCIL_TYPE:
 306    case GL_FRAMEBUFFER_RENDERABLE:
 307    case GL_FRAMEBUFFER_RENDERABLE_LAYERED:
 308    case GL_FRAMEBUFFER_BLEND:
 309    case GL_READ_PIXELS:
 310    case GL_READ_PIXELS_FORMAT:
 311    case GL_READ_PIXELS_TYPE:
 312    case GL_TEXTURE_IMAGE_FORMAT:
 313    case GL_TEXTURE_IMAGE_TYPE:
 314    case GL_GET_TEXTURE_IMAGE_FORMAT:
 315    case GL_GET_TEXTURE_IMAGE_TYPE:
 316    case GL_MANUAL_GENERATE_MIPMAP:
 317    case GL_AUTO_GENERATE_MIPMAP:
 318    case GL_COLOR_ENCODING:
 319    case GL_SRGB_READ:
 320    case GL_SRGB_WRITE:
 321    case GL_SRGB_DECODE_ARB:
 322    case GL_FILTER:
 323    case GL_VERTEX_TEXTURE:
 324    case GL_TESS_CONTROL_TEXTURE:
 325    case GL_TESS_EVALUATION_TEXTURE:
 326    case GL_GEOMETRY_TEXTURE:
 327    case GL_FRAGMENT_TEXTURE:
 328    case GL_COMPUTE_TEXTURE:
 329    case GL_TEXTURE_SHADOW:
 330    case GL_TEXTURE_GATHER:
 331    case GL_TEXTURE_GATHER_SHADOW:
 332    case GL_SHADER_IMAGE_LOAD:
 333    case GL_SHADER_IMAGE_STORE:
 334    case GL_SHADER_IMAGE_ATOMIC:
 335    case GL_IMAGE_COMPATIBILITY_CLASS:
 336    case GL_IMAGE_PIXEL_FORMAT:
 337    case GL_IMAGE_PIXEL_TYPE:
 338    case GL_IMAGE_FORMAT_COMPATIBILITY_TYPE:
 339    case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST:
 340    case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST:
 341    case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE:
 342    case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE:
 343    case GL_CLEAR_BUFFER:
 344    case GL_TEXTURE_VIEW:
 345    case GL_VIEW_COMPATIBILITY_CLASS:
 346       buffer[0] = GL_NONE;
 347       break;
 348
 349    case GL_INTERNALFORMAT_SUPPORTED:
 350    case GL_COLOR_COMPONENTS:
 351    case GL_DEPTH_COMPONENTS:
 352    case GL_STENCIL_COMPONENTS:
 353    case GL_COLOR_RENDERABLE:
 354    case GL_DEPTH_RENDERABLE:
 355    case GL_STENCIL_RENDERABLE:
 356    case GL_MIPMAP:
 357    case GL_TEXTURE_COMPRESSED:
 358       buffer[0] = GL_FALSE;
 359       break;
 360
 361    default:
 362       unreachable("invalid 'pname'");
 363    }
 364 }
 365
 366 static bool
 367 _is_target_supported(struct gl_context *ctx, GLenum target)
 368 {
 369    /* The ARB_internalformat_query2 spec says:
 370     *
 371     *     "if a particular type of <target> is not supported by the
 372     *     implementation the "unsupported" answer should be given.
 373     *     This is not an error."
 374     */
 375    switch(target){
 376    case GL_TEXTURE_2D:
 377    case GL_TEXTURE_3D:
 378       break;
 379
 380    case GL_TEXTURE_1D:
 381       if (!_mesa_is_desktop_gl(ctx))
 382          return false;
 383       break;
 384
 385    case GL_TEXTURE_1D_ARRAY:
 386       if (!_mesa_has_EXT_texture_array(ctx))
 387          return false;
 388       break;
 389
 390    case GL_TEXTURE_2D_ARRAY:
 391       if (!(_mesa_has_EXT_texture_array(ctx) || _mesa_is_gles3(ctx)))
 392          return false;
 393       break;
 394
 395    case GL_TEXTURE_CUBE_MAP:
 396       if (!_mesa_has_ARB_texture_cube_map(ctx))
 397          return false;
 398       break;
 399
 400    case GL_TEXTURE_CUBE_MAP_ARRAY:
 401       if (!_mesa_has_ARB_texture_cube_map_array(ctx))
 402          return false;
 403       break;
 404
 405    case GL_TEXTURE_RECTANGLE:
 406       if (!_mesa_has_NV_texture_rectangle(ctx))
 407           return false;
 408       break;
 409
 410    case GL_TEXTURE_BUFFER:
 411       if (!_mesa_has_ARB_texture_buffer_object(ctx))
 412          return false;
 413       break;
 414
 415    case GL_RENDERBUFFER:
 416       if (!(_mesa_has_ARB_framebuffer_object(ctx) ||
 417             _mesa_is_gles3(ctx)))
 418          return false;
 419       break;
 420
 421    case GL_TEXTURE_2D_MULTISAMPLE:
 422    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
 423       if (!(_mesa_has_ARB_texture_multisample(ctx) ||
 424             _mesa_is_gles31(ctx)))
 425          return false;
 426       break;
 427
 428    default:
 429       unreachable("invalid target");
 430    }
 431
 432    return true;
 433 }
 434
 435 /* default implementation of QueryInternalFormat driverfunc, for
 436  * drivers not implementing ARB_internalformat_query2.
 437  */
 438 void
 439 _mesa_query_internal_format_default(struct gl_context *ctx, GLenum target,
 440                                     GLenum internalFormat, GLenum pname,
 441                                     GLint *params)
 442 {
 443    (void) ctx;
 444    (void) target;
 445    (void) internalFormat;
 446
 447    switch (pname) {
 448    case GL_SAMPLES:
 449    case GL_NUM_SAMPLE_COUNTS:
 450       params[0] = 1;
 451       break;
 452    default:
 453       /* @TODO: handle default values for all the different pnames. */
 454       break;
 455    }
 456 }
 457
 458 void GLAPIENTRY
 459 _mesa_GetInternalformativ(GLenum target, GLenum internalformat, GLenum pname,
 460                           GLsizei bufSize, GLint *params)
 461 {
 462    GLint buffer[16];
 463    GET_CURRENT_CONTEXT(ctx);
 464
 465    ASSERT_OUTSIDE_BEGIN_END(ctx);
 466
 467    if (!ctx->Extensions.ARB_internalformat_query) {
 468       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetInternalformativ");
 469       return;
 470    }
 471
 472    assert(ctx->Driver.QueryInternalFormat != NULL);
 473
 474    /* The ARB_internalformat_query spec says:
 475     *
 476     *     "If the <target> parameter to GetInternalformativ is not one of
 477     *     TEXTURE_2D_MULTISAMPLE, TEXTURE_2D_MULTISAMPLE_ARRAY or RENDERBUFFER
 478     *     then an INVALID_ENUM error is generated."
 479     */
 480    switch (target) {
 481    case GL_RENDERBUFFER:
 482       break;
 483
 484    case GL_TEXTURE_2D_MULTISAMPLE:
 485    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
 486       /* These enums are only valid if ARB_texture_multisample is supported */
 487       if ((_mesa_is_desktop_gl(ctx) &&
 488            ctx->Extensions.ARB_texture_multisample) ||
 489           _mesa_is_gles31(ctx))
 490          break;
 491
 492    default:
 493       _mesa_error(ctx, GL_INVALID_ENUM,
 494                   "glGetInternalformativ(target=%s)",
 495                   _mesa_enum_to_string(target));
 496       return;
 497    }
 498
 499    /* The ARB_internalformat_query spec says:
 500     *
 501     *     "If the <internalformat> parameter to GetInternalformativ is not
 502     *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
 503     *     generated."
 504     *
 505     * Page 243 of the GLES 3.0.4 spec says this for GetInternalformativ:
 506     *
 507     *     "internalformat must be color-renderable, depth-renderable or
 508     *     stencilrenderable (as defined in section 4.4.4)."
 509     *
 510     * Section 4.4.4 on page 212 of the same spec says:
 511     *
 512     *     "An internal format is color-renderable if it is one of the
 513     *     formats from table 3.13 noted as color-renderable or if it
 514     *     is unsized format RGBA or RGB."
 515     *
 516     * Therefore, we must accept GL_RGB and GL_RGBA here.
 517     */
 518    if (internalformat != GL_RGB && internalformat != GL_RGBA &&
 519        _mesa_base_fbo_format(ctx, internalformat) == 0) {
 520       _mesa_error(ctx, GL_INVALID_ENUM,
 521                   "glGetInternalformativ(internalformat=%s)",
 522                   _mesa_enum_to_string(internalformat));
 523       return;
 524    }
 525
 526    /* The ARB_internalformat_query spec says:
 527     *
 528     *     "If the <bufSize> parameter to GetInternalformativ is negative, then
 529     *     an INVALID_VALUE error is generated."
 530     */
 531    if (bufSize < 0) {
 532       _mesa_error(ctx, GL_INVALID_VALUE,
 533                   "glGetInternalformativ(target=%s)",
 534                   _mesa_enum_to_string(target));
 535       return;
 536    }
 537
 538    /* initialize the contents of the temporary buffer */
 539    memcpy(buffer, params, MIN2(bufSize, 16) * sizeof(GLint));
 540
 541    switch (pname) {
 542    case GL_SAMPLES:
 543       ctx->Driver.QueryInternalFormat(ctx, target, internalformat, pname,
 544                                       buffer);
 545       break;
 546    case GL_NUM_SAMPLE_COUNTS: {
 547       if ((ctx->API == API_OPENGLES2 && ctx->Version == 30) &&
 548           _mesa_is_enum_format_integer(internalformat)) {
 549          /* From GL ES 3.0 specification, section 6.1.15 page 236: "Since
 550           * multisampling is not supported for signed and unsigned integer
 551           * internal formats, the value of NUM_SAMPLE_COUNTS will be zero
 552           * for such formats.
 553           *
 554           * Such a restriction no longer exists in GL ES 3.1.
 555           */
 556          buffer[0] = 0;
 557       } else {
 558          ctx->Driver.QueryInternalFormat(ctx, target, internalformat, pname,
 559                                          buffer);
 560       }
 561       break;
 562    }
 563    default:
 564       _mesa_error(ctx, GL_INVALID_ENUM,
 565                   "glGetInternalformativ(pname=%s)",
 566                   _mesa_enum_to_string(pname));
 567       return;
 568    }
 569
 570    if (bufSize != 0 && params == NULL) {
 571       /* Emit a warning to aid application debugging, but go ahead and do the
 572        * memcpy (and probably crash) anyway.
 573        */
 574       _mesa_warning(ctx,
 575                     "glGetInternalformativ(bufSize = %d, but params = NULL)",
 576                     bufSize);
 577    }
 578
 579    /* Copy the data from the temporary buffer to the buffer supplied by the
 580     * application.  Clamp the size of the copy to the size supplied by the
 581     * application.
 582     */
 583    memcpy(params, buffer, MIN2(bufSize, 16) * sizeof(GLint));
 584
 585    return;
 586 }