reactos/dll/opengl/mesa/main/texgetimage.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.7
   4  *
   5  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   6  * Copyright (c) 2009 VMware, Inc.
   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 /**
  28  * Code for glGetTexImage() and glGetCompressedTexImage().
  29  */
  30
  31
  32 #include "glheader.h"
  33 #include "bufferobj.h"
  34 #include "enums.h"
  35 #include "context.h"
  36 #include "formats.h"
  37 #include "format_unpack.h"
  38 #include "image.h"
  39 #include "mfeatures.h"
  40 #include "mtypes.h"
  41 #include "pack.h"
  42 #include "pbo.h"
  43 #include "texgetimage.h"
  44 #include "teximage.h"
  45
  46
  47
  48 /**
  49  * Can the given type represent negative values?
  50  */
  51 static inline GLboolean
  52 type_needs_clamping(GLenum type)
  53 {
  54    switch (type) {
  55    case GL_BYTE:
  56    case GL_SHORT:
  57    case GL_INT:
  58    case GL_FLOAT:
  59    case GL_HALF_FLOAT_ARB:
  60    case GL_UNSIGNED_INT_10F_11F_11F_REV:
  61    case GL_UNSIGNED_INT_5_9_9_9_REV:
  62       return GL_FALSE;
  63    default:
  64       return GL_TRUE;
  65    }
  66 }
  67
  68
  69 /**
  70  * glGetTexImage for depth/Z pixels.
  71  */
  72 static void
  73 get_tex_depth(struct gl_context *ctx, GLuint dimensions,
  74               GLenum format, GLenum type, GLvoid *pixels,
  75               struct gl_texture_image *texImage)
  76 {
  77    const GLint width = texImage->Width;
  78    const GLint height = texImage->Height;
  79    const GLint depth = texImage->Depth;
  80    GLint img, row;
  81    GLfloat *depthRow = (GLfloat *) malloc(width * sizeof(GLfloat));
  82
  83    if (!depthRow) {
  84       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
  85       return;
  86    }
  87
  88    for (img = 0; img < depth; img++) {
  89       GLubyte *srcMap;
  90       GLint srcRowStride;
  91
  92       /* map src texture buffer */
  93       ctx->Driver.MapTextureImage(ctx, texImage, img,
  94                                   0, 0, width, height, GL_MAP_READ_BIT,
  95                                   &srcMap, &srcRowStride);
  96
  97       if (srcMap) {
  98          for (row = 0; row < height; row++) {
  99             void *dest = _mesa_image_address(dimensions, &ctx->Pack, pixels,
 100                                              width, height, format, type,
 101                                              img, row, 0);
 102             const GLubyte *src = srcMap + row * srcRowStride;
 103             _mesa_unpack_float_z_row(texImage->TexFormat, width, src, depthRow);
 104             _mesa_pack_depth_span(ctx, width, dest, type, depthRow, &ctx->Pack);
 105          }
 106
 107          ctx->Driver.UnmapTextureImage(ctx, texImage, img);
 108       }
 109       else {
 110          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
 111          break;
 112       }
 113    }
 114
 115    free(depthRow);
 116 }
 117
 118 /**
 119  * glGetTexImage for YCbCr pixels.
 120  */
 121 static void
 122 get_tex_ycbcr(struct gl_context *ctx, GLuint dimensions,
 123               GLenum format, GLenum type, GLvoid *pixels,
 124               struct gl_texture_image *texImage)
 125 {
 126    const GLint width = texImage->Width;
 127    const GLint height = texImage->Height;
 128    const GLint depth = texImage->Depth;
 129    GLint img, row;
 130
 131    for (img = 0; img < depth; img++) {
 132       GLubyte *srcMap;
 133       GLint rowstride;
 134
 135       /* map src texture buffer */
 136       ctx->Driver.MapTextureImage(ctx, texImage, img,
 137                                   0, 0, width, height, GL_MAP_READ_BIT,
 138                                   &srcMap, &rowstride);
 139
 140       if (srcMap) {
 141          for (row = 0; row < height; row++) {
 142             const GLubyte *src = srcMap + row * rowstride;
 143             void *dest = _mesa_image_address(dimensions, &ctx->Pack, pixels,
 144                                              width, height, format, type,
 145                                              img, row, 0);
 146             memcpy(dest, src, width * sizeof(GLushort));
 147
 148             /* check for byte swapping */
 149             if ((texImage->TexFormat == MESA_FORMAT_YCBCR
 150                  && type == GL_UNSIGNED_SHORT_8_8_REV_MESA) ||
 151                 (texImage->TexFormat == MESA_FORMAT_YCBCR_REV
 152                  && type == GL_UNSIGNED_SHORT_8_8_MESA)) {
 153                if (!ctx->Pack.SwapBytes)
 154                   _mesa_swap2((GLushort *) dest, width);
 155             }
 156             else if (ctx->Pack.SwapBytes) {
 157                _mesa_swap2((GLushort *) dest, width);
 158             }
 159          }
 160
 161          ctx->Driver.UnmapTextureImage(ctx, texImage, img);
 162       }
 163       else {
 164          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
 165          break;
 166       }
 167    }
 168 }
 169
 170 /**
 171  * Get an uncompressed color texture image.
 172  */
 173 static void
 174 get_tex_rgba_uncompressed(struct gl_context *ctx, GLuint dimensions,
 175                           GLenum format, GLenum type, GLvoid *pixels,
 176                           struct gl_texture_image *texImage,
 177                           GLbitfield transferOps)
 178 {
 179    const gl_format texFormat = texImage->TexFormat;
 180    const GLuint width = texImage->Width;
 181    const GLenum destBaseFormat = _mesa_base_tex_format(ctx, format);
 182    GLenum rebaseFormat = GL_NONE;
 183    GLuint height = texImage->Height;
 184    GLuint depth = texImage->Depth;
 185    GLuint img, row;
 186    GLfloat (*rgba)[4];
 187    GLuint (*rgba_uint)[4];
 188    GLboolean is_integer = _mesa_is_format_integer_color(texImage->TexFormat);
 189
 190    /* Allocate buffer for one row of texels */
 191    rgba = (GLfloat (*)[4]) malloc(4 * width * sizeof(GLfloat));
 192    rgba_uint = (GLuint (*)[4]) rgba;
 193    if (!rgba) {
 194       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage()");
 195       return;
 196    }
 197
 198    if (texImage->_BaseFormat == GL_LUMINANCE ||
 199        texImage->_BaseFormat == GL_INTENSITY ||
 200        texImage->_BaseFormat == GL_LUMINANCE_ALPHA) {
 201       /* If a luminance (or intensity) texture is read back as RGB(A), the
 202        * returned value should be (L,0,0,1), not (L,L,L,1).  Set rebaseFormat
 203        * here to get G=B=0.
 204        */
 205       rebaseFormat = texImage->_BaseFormat;
 206    }
 207    else if ((texImage->_BaseFormat == GL_RGBA ||
 208              texImage->_BaseFormat == GL_RGB) &&
 209             (destBaseFormat == GL_LUMINANCE ||
 210              destBaseFormat == GL_LUMINANCE_ALPHA ||
 211              destBaseFormat == GL_LUMINANCE_INTEGER_EXT ||
 212              destBaseFormat == GL_LUMINANCE_ALPHA_INTEGER_EXT)) {
 213       /* If we're reading back an RGB(A) texture as luminance then we need
 214        * to return L=tex(R).  Note, that's different from glReadPixels which
 215        * returns L=R+G+B.
 216        */
 217       rebaseFormat = GL_LUMINANCE_ALPHA; /* this covers GL_LUMINANCE too */
 218    }
 219
 220    for (img = 0; img < depth; img++) {
 221       GLubyte *srcMap;
 222       GLint rowstride;
 223
 224       /* map src texture buffer */
 225       ctx->Driver.MapTextureImage(ctx, texImage, img,
 226                                   0, 0, width, height, GL_MAP_READ_BIT,
 227                                   &srcMap, &rowstride);
 228       if (srcMap) {
 229          for (row = 0; row < height; row++) {
 230             const GLubyte *src = srcMap + row * rowstride;
 231             void *dest = _mesa_image_address(dimensions, &ctx->Pack, pixels,
 232                                              width, height, format, type,
 233                                              img, row, 0);
 234
 235             if (is_integer) {
 236                _mesa_unpack_uint_rgba_row(texFormat, width, src, rgba_uint);
 237                if (rebaseFormat)
 238                   _mesa_rebase_rgba_uint(width, rgba_uint, rebaseFormat);
 239                _mesa_pack_rgba_span_int(ctx, width, rgba_uint,
 240                                         format, type, dest);
 241             } else {
 242                _mesa_unpack_rgba_row(texFormat, width, src, rgba);
 243                if (rebaseFormat)
 244                   _mesa_rebase_rgba_float(width, rgba, rebaseFormat);
 245                _mesa_pack_rgba_span_float(ctx, width, (GLfloat (*)[4]) rgba,
 246                                           format, type, dest,
 247                                           &ctx->Pack, transferOps);
 248             }
 249          }
 250
 251          /* Unmap the src texture buffer */
 252          ctx->Driver.UnmapTextureImage(ctx, texImage, img);
 253       }
 254       else {
 255          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
 256          break;
 257       }
 258    }
 259
 260    free(rgba);
 261 }
 262
 263
 264 /**
 265  * glGetTexImage for color formats (RGBA, RGB, alpha, LA, etc).
 266  * Compressed textures are handled here as well.
 267  */
 268 static void
 269 get_tex_rgba(struct gl_context *ctx, GLuint dimensions,
 270              GLenum format, GLenum type, GLvoid *pixels,
 271              struct gl_texture_image *texImage)
 272 {
 273    const GLenum dataType = _mesa_get_format_datatype(texImage->TexFormat);
 274    GLbitfield transferOps = 0x0;
 275
 276    /* In general, clamping does not apply to glGetTexImage, except when
 277     * the returned type of the image can't hold negative values.
 278     */
 279    if (type_needs_clamping(type)) {
 280       /* the returned image type can't have negative values */
 281       if (dataType == GL_FLOAT ||
 282           dataType == GL_SIGNED_NORMALIZED ||
 283           format == GL_LUMINANCE ||
 284           format == GL_LUMINANCE_ALPHA) {
 285          transferOps |= IMAGE_CLAMP_BIT;
 286       }
 287    }
 288    /* This applies to RGB, RGBA textures. if the format is either LUMINANCE
 289     * or LUMINANCE ALPHA, luminance (L) is computed as L=R+G+B .we need to
 290     * clamp the sum to [0,1].
 291     */
 292    else if ((format == GL_LUMINANCE ||
 293             format == GL_LUMINANCE_ALPHA) &&
 294             dataType == GL_UNSIGNED_NORMALIZED) {
 295       transferOps |= IMAGE_CLAMP_BIT;
 296    }
 297    get_tex_rgba_uncompressed(ctx, dimensions, format, type,
 298                              pixels, texImage, transferOps);
 299 }
 300
 301
 302 /**
 303  * Try to do glGetTexImage() with simple memcpy().
 304  * \return GL_TRUE if done, GL_FALSE otherwise
 305  */
 306 static GLboolean
 307 get_tex_memcpy(struct gl_context *ctx, GLenum format, GLenum type,
 308                GLvoid *pixels,
 309                struct gl_texture_image *texImage)
 310 {
 311    const GLenum target = texImage->TexObject->Target;
 312    GLboolean memCopy = GL_FALSE;
 313
 314    /*
 315     * Check if the src/dst formats are compatible.
 316     * Also note that GL's pixel transfer ops don't apply to glGetTexImage()
 317     * so we don't have to worry about those.
 318     * XXX more format combinations could be supported here.
 319     */
 320    if (target == GL_TEXTURE_1D ||
 321        target == GL_TEXTURE_2D ||
 322        _mesa_is_cube_face(target)) {
 323       if ((texImage->TexFormat == MESA_FORMAT_ARGB8888) &&
 324           format == GL_BGRA &&
 325           (type == GL_UNSIGNED_BYTE || type == GL_UNSIGNED_INT_8_8_8_8_REV) &&
 326           !ctx->Pack.SwapBytes &&
 327           _mesa_little_endian()) {
 328          memCopy = GL_TRUE;
 329       }
 330       else if ((texImage->TexFormat == MESA_FORMAT_AL88) &&
 331                format == GL_LUMINANCE_ALPHA &&
 332                type == GL_UNSIGNED_BYTE &&
 333                !ctx->Pack.SwapBytes &&
 334                _mesa_little_endian()) {
 335          memCopy = GL_TRUE;
 336       }
 337       else if ((texImage->TexFormat == MESA_FORMAT_L8) &&
 338                format == GL_LUMINANCE &&
 339                type == GL_UNSIGNED_BYTE) {
 340          memCopy = GL_TRUE;
 341       }
 342       else if (texImage->TexFormat == MESA_FORMAT_L16 &&
 343                format == GL_LUMINANCE &&
 344                type == GL_UNSIGNED_SHORT) {
 345          memCopy = GL_TRUE;
 346       }
 347       else if (texImage->TexFormat == MESA_FORMAT_A8 &&
 348                format == GL_ALPHA &&
 349                type == GL_UNSIGNED_BYTE) {
 350          memCopy = GL_TRUE;
 351       }
 352       else if (texImage->TexFormat == MESA_FORMAT_A16 &&
 353                format == GL_ALPHA &&
 354                type == GL_UNSIGNED_SHORT) {
 355          memCopy = GL_TRUE;
 356       }
 357    }
 358
 359    if (memCopy) {
 360       const GLuint bpp = _mesa_get_format_bytes(texImage->TexFormat);
 361       const GLuint bytesPerRow = texImage->Width * bpp;
 362       GLubyte *dst =
 363          _mesa_image_address2d(&ctx->Pack, pixels, texImage->Width,
 364                                texImage->Height, format, type, 0, 0);
 365       const GLint dstRowStride =
 366          _mesa_image_row_stride(&ctx->Pack, texImage->Width, format, type);
 367       GLubyte *src;
 368       GLint srcRowStride;
 369
 370       /* map src texture buffer */
 371       ctx->Driver.MapTextureImage(ctx, texImage, 0,
 372                                   0, 0, texImage->Width, texImage->Height,
 373                                   GL_MAP_READ_BIT, &src, &srcRowStride);
 374
 375       if (src) {
 376          if (bytesPerRow == dstRowStride && bytesPerRow == srcRowStride) {
 377             memcpy(dst, src, bytesPerRow * texImage->Height);
 378          }
 379          else {
 380             GLuint row;
 381             for (row = 0; row < texImage->Height; row++) {
 382                memcpy(dst, src, bytesPerRow);
 383                dst += dstRowStride;
 384                src += srcRowStride;
 385             }
 386          }
 387
 388          /* unmap src texture buffer */
 389          ctx->Driver.UnmapTextureImage(ctx, texImage, 0);
 390       }
 391       else {
 392          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage");
 393       }
 394    }
 395
 396    return memCopy;
 397 }
 398
 399
 400 /**
 401  * This is the software fallback for Driver.GetTexImage().
 402  * All error checking will have been done before this routine is called.
 403  * We'll call ctx->Driver.MapTextureImage() to access the data, then
 404  * unmap with ctx->Driver.UnmapTextureImage().
 405  */
 406 void
 407 _mesa_get_teximage(struct gl_context *ctx,
 408                    GLenum format, GLenum type, GLvoid *pixels,
 409                    struct gl_texture_image *texImage)
 410 {
 411    GLuint dimensions;
 412
 413    switch (texImage->TexObject->Target) {
 414    case GL_TEXTURE_1D:
 415       dimensions = 1;
 416       break;
 417    case GL_TEXTURE_3D:
 418       dimensions = 3;
 419       break;
 420    default:
 421       dimensions = 2;
 422    }
 423
 424    /* map dest buffer, if PBO */
 425    if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 426       /* Packing texture image into a PBO.
 427        * Map the (potentially) VRAM-based buffer into our process space so
 428        * we can write into it with the code below.
 429        * A hardware driver might use a sophisticated blit to move the
 430        * texture data to the PBO if the PBO is in VRAM along with the texture.
 431        */
 432       GLubyte *buf = (GLubyte *)
 433          ctx->Driver.MapBufferRange(ctx, 0, ctx->Pack.BufferObj->Size,
 434                                     GL_MAP_WRITE_BIT, ctx->Pack.BufferObj);
 435       if (!buf) {
 436          /* out of memory or other unexpected error */
 437          _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGetTexImage(map PBO failed)");
 438          return;
 439       }
 440       /* <pixels> was an offset into the PBO.
 441        * Now make it a real, client-side pointer inside the mapped region.
 442        */
 443       pixels = ADD_POINTERS(buf, pixels);
 444    }
 445
 446    if (get_tex_memcpy(ctx, format, type, pixels, texImage)) {
 447       /* all done */
 448    }
 449    else if (format == GL_DEPTH_COMPONENT) {
 450       get_tex_depth(ctx, dimensions, format, type, pixels, texImage);
 451    }
 452    else if (format == GL_YCBCR_MESA) {
 453       get_tex_ycbcr(ctx, dimensions, format, type, pixels, texImage);
 454    }
 455    else {
 456       get_tex_rgba(ctx, dimensions, format, type, pixels, texImage);
 457    }
 458
 459    if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 460       ctx->Driver.UnmapBuffer(ctx, ctx->Pack.BufferObj);
 461    }
 462 }
 463
 464 /**
 465  * Do error checking for a glGetTexImage() call.
 466  * \return GL_TRUE if any error, GL_FALSE if no errors.
 467  */
 468 static GLboolean
 469 getteximage_error_check(struct gl_context *ctx, GLenum target, GLint level,
 470                         GLenum format, GLenum type, GLsizei clientMemSize,
 471                         GLvoid *pixels )
 472 {
 473    struct gl_texture_object *texObj;
 474    struct gl_texture_image *texImage;
 475    const GLint maxLevels = _mesa_max_texture_levels(ctx, target);
 476    const GLuint dimensions = (target == GL_TEXTURE_3D) ? 3 : 2;
 477    GLenum baseFormat, err;
 478
 479    if (maxLevels == 0) {
 480       _mesa_error(ctx, GL_INVALID_ENUM, "glGetTexImage(target=0x%x)", target);
 481       return GL_TRUE;
 482    }
 483
 484    if (level < 0 || level >= maxLevels) {
 485       _mesa_error( ctx, GL_INVALID_VALUE, "glGetTexImage(level)" );
 486       return GL_TRUE;
 487    }
 488
 489    if (_mesa_sizeof_packed_type(type) <= 0) {
 490       _mesa_error( ctx, GL_INVALID_ENUM, "glGetTexImage(type)" );
 491       return GL_TRUE;
 492    }
 493
 494    if (_mesa_components_in_format(format) <= 0 ||
 495        format == GL_STENCIL_INDEX ||
 496        format == GL_COLOR_INDEX) {
 497       _mesa_error( ctx, GL_INVALID_ENUM, "glGetTexImage(format)" );
 498       return GL_TRUE;
 499    }
 500
 501    if (_mesa_is_depth_format(format)) {
 502       _mesa_error(ctx, GL_INVALID_ENUM, "glGetTexImage(format)");
 503       return GL_TRUE;
 504    }
 505
 506    if (!ctx->Extensions.MESA_ycbcr_texture && _mesa_is_ycbcr_format(format)) {
 507       _mesa_error(ctx, GL_INVALID_ENUM, "glGetTexImage(format)");
 508       return GL_TRUE;
 509    }
 510
 511    err = _mesa_error_check_format_and_type(ctx, format, type);
 512    if (err != GL_NO_ERROR) {
 513       _mesa_error(ctx, err, "glGetTexImage(format/type)");
 514       return GL_TRUE;
 515    }
 516
 517    texObj = _mesa_select_tex_object(ctx, target);
 518
 519    if (!texObj || _mesa_is_proxy_texture(target)) {
 520       _mesa_error(ctx, GL_INVALID_ENUM, "glGetTexImage(target)");
 521       return GL_TRUE;
 522    }
 523
 524    texImage = _mesa_select_tex_image(ctx, texObj, target, level);
 525    if (!texImage) {
 526       /* non-existant texture image */
 527       return GL_TRUE;
 528    }
 529
 530    baseFormat = _mesa_get_format_base_format(texImage->TexFormat);
 531
 532    /* Make sure the requested image format is compatible with the
 533     * texture's format.
 534     */
 535    if (_mesa_is_color_format(format)
 536        && !_mesa_is_color_format(baseFormat)) {
 537       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetTexImage(format mismatch)");
 538       return GL_TRUE;
 539    }
 540    else if (_mesa_is_depth_format(format)
 541             && !_mesa_is_depth_format(baseFormat)) {
 542       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetTexImage(format mismatch)");
 543       return GL_TRUE;
 544    }
 545    else if (_mesa_is_ycbcr_format(format)
 546             && !_mesa_is_ycbcr_format(baseFormat)) {
 547       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetTexImage(format mismatch)");
 548       return GL_TRUE;
 549    }
 550
 551    if (!_mesa_validate_pbo_access(dimensions, &ctx->Pack, texImage->Width,
 552                                   texImage->Height, texImage->Depth,
 553                                   format, type, clientMemSize, pixels)) {
 554       if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 555          _mesa_error(ctx, GL_INVALID_OPERATION,
 556                      "glGetTexImage(out of bounds PBO access)");
 557       } else {
 558          _mesa_error(ctx, GL_INVALID_OPERATION,
 559                      "glGetnTexImageARB(out of bounds access:"
 560                      " bufSize (%d) is too small)", clientMemSize);
 561       }
 562       return GL_TRUE;
 563    }
 564
 565    if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 566       /* PBO should not be mapped */
 567       if (_mesa_bufferobj_mapped(ctx->Pack.BufferObj)) {
 568          _mesa_error(ctx, GL_INVALID_OPERATION,
 569                      "glGetTexImage(PBO is mapped)");
 570          return GL_TRUE;
 571       }
 572    }
 573
 574    return GL_FALSE;
 575 }
 576
 577
 578
 579 /**
 580  * Get texture image.  Called by glGetTexImage.
 581  *
 582  * \param target texture target.
 583  * \param level image level.
 584  * \param format pixel data format for returned image.
 585  * \param type pixel data type for returned image.
 586  * \param bufSize size of the pixels data buffer.
 587  * \param pixels returned pixel data.
 588  */
 589 void GLAPIENTRY
 590 _mesa_GetnTexImageARB( GLenum target, GLint level, GLenum format,
 591                        GLenum type, GLsizei bufSize, GLvoid *pixels )
 592 {
 593    struct gl_texture_object *texObj;
 594    struct gl_texture_image *texImage;
 595    GET_CURRENT_CONTEXT(ctx);
 596    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 597
 598    if (getteximage_error_check(ctx, target, level, format, type,
 599                                bufSize, pixels)) {
 600       return;
 601    }
 602
 603    if (!_mesa_is_bufferobj(ctx->Pack.BufferObj) && !pixels) {
 604       /* not an error, do nothing */
 605       return;
 606    }
 607
 608    texObj = _mesa_select_tex_object(ctx, target);
 609    texImage = _mesa_select_tex_image(ctx, texObj, target, level);
 610
 611    if (_mesa_is_zero_size_texture(texImage))
 612       return;
 613
 614    if (MESA_VERBOSE & (VERBOSE_API | VERBOSE_TEXTURE)) {
 615       _mesa_debug(ctx, "glGetTexImage(tex %u) format = %s, w=%d, h=%d,"
 616                   " dstFmt=0x%x, dstType=0x%x\n",
 617                   texObj->Name,
 618                   _mesa_get_format_name(texImage->TexFormat),
 619                   texImage->Width, texImage->Height,
 620                   format, type);
 621    }
 622
 623    _mesa_lock_texture(ctx, texObj);
 624    {
 625       ctx->Driver.GetTexImage(ctx, format, type, pixels, texImage);
 626    }
 627    _mesa_unlock_texture(ctx, texObj);
 628 }
 629
 630
 631 void GLAPIENTRY
 632 _mesa_GetTexImage( GLenum target, GLint level, GLenum format,
 633                    GLenum type, GLvoid *pixels )
 634 {
 635    _mesa_GetnTexImageARB(target, level, format, type, INT_MAX, pixels);
 636 }