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  11   <h1>The Mesa 3D Graphics Library</h1>
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  16
  17 <h1>Development Notes</h1>
  18
  19
  20 <ul>
  21 <li><a href="#style">Coding Style</a>
  22 <li><a href="#submitting">Submitting Patches</a>
  23 <li><a href="#release">Making a New Mesa Release</a>
  24 <li><a href="#extensions">Adding Extensions</a>
  25 </ul>
  26
  27
  28 <h2 id="style">Coding Style</h2>
  29
  30 <p>
  31 Mesa is over 20 years old and the coding style has evolved over time.
  32 Some old parts use a style that's a bit out of date.
  33 If the guidelines below don't cover something, try following the format of
  34 existing, neighboring code.
  35 </p>
  36
  37 <p>
  38 Basic formatting guidelines
  39 </p>
  40
  41 <ul>
  42 <li>3-space indentation, no tabs.
  43 <li>Limit lines to 78 or fewer characters.  The idea is to prevent line
  44 wrapping in 80-column editors and terminals.  There are exceptions, such
  45 as if you're defining a large, static table of information.
  46 <li>Opening braces go on the same line as the if/for/while statement.
  47 For example:
  48 <pre>
  49    if (condition) {
  50       foo;
  51    } else {
  52       bar;
  53    }
  54 </pre>
  55
  56 <li>Put a space before/after operators.  For example, <tt>a = b + c;</tt>
  57 and not <tt>a=b+c;</tt>
  58
  59 <li>This GNU indent command generally does the right thing for formatting:
  60 <pre>
  61    indent -br -i3 -npcs --no-tabs infile.c -o outfile.c
  62 </pre>
  63
  64 <li>Use comments wherever you think it would be helpful for other developers.
  65 Several specific cases and style examples follow.  Note that we roughly
  66 follow <a href="http://www.stack.nl/~dimitri/doxygen/">Doxygen</a> conventions.
  67 <br>
  68 <br>
  69 Single-line comments:
  70 <pre>
  71    /* null-out pointer to prevent dangling reference below */
  72    bufferObj = NULL;
  73 </pre>
  74 Or,
  75 <pre>
  76    bufferObj = NULL;  /* prevent dangling reference below */
  77 </pre>
  78 Multi-line comment:
  79 <pre>
  80    /* If this is a new buffer object id, or one which was generated but
  81     * never used before, allocate a buffer object now.
  82     */
  83 </pre>
  84 We try to quote the OpenGL specification where prudent:
  85 <pre>
  86    /* Page 38 of the PDF of the OpenGL ES 3.0 spec says:
  87     *
  88     *     "An INVALID_OPERATION error is generated for any of the following
  89     *     conditions:
  90     *
  91     *     * <length> is zero."
  92     *
  93     * Additionally, page 94 of the PDF of the OpenGL 4.5 core spec
  94     * (30.10.2014) also says this, so it's no longer allowed for desktop GL,
  95     * either.
  96     */
  97 </pre>
  98 Function comment example:
  99 <pre>
 100    /**
 101     * Create and initialize a new buffer object.  Called via the
 102     * ctx->Driver.CreateObject() driver callback function.
 103     * \param  name  integer name of the object
 104     * \param  type  one of GL_FOO, GL_BAR, etc.
 105     * \return  pointer to new object or NULL if error
 106     */
 107    struct gl_object *
 108    _mesa_create_object(GLuint name, GLenum type)
 109    {
 110       /* function body */
 111    }
 112 </pre>
 113
 114 <li>Put the function return type and qualifiers on one line and the function
 115 name and parameters on the next, as seen above.  This makes it easy to use
 116 <code>grep ^function_name dir/*</code> to find function definitions.  Also,
 117 the opening brace goes on the next line by itself (see above.)
 118
 119 <li>Function names follow various conventions depending on the type of function:
 120 <pre>
 121    glFooBar()       - a public GL entry point (in glapi_dispatch.c)
 122    _mesa_FooBar()   - the internal immediate mode function
 123    save_FooBar()    - retained mode (display list) function in dlist.c
 124    foo_bar()        - a static (private) function
 125    _mesa_foo_bar()  - an internal non-static Mesa function
 126 </pre>
 127
 128 <li>Constants, macros and enumerant names are ALL_UPPERCASE, with _ between
 129 words.
 130 <li>Mesa usually uses camel case for local variables (Ex: "localVarname")
 131 while gallium typically uses underscores (Ex: "local_var_name").
 132 <li>Global variables are almost never used because Mesa should be thread-safe.
 133
 134 <li>Booleans.  Places that are not directly visible to the GL API
 135 should prefer the use of <tt>bool</tt>, <tt>true</tt>, and
 136 <tt>false</tt> over <tt>GLboolean</tt>, <tt>GL_TRUE</tt>, and
 137 <tt>GL_FALSE</tt>.  In C code, this may mean that
 138 <tt>#include &lt;stdbool.h&gt;</tt> needs to be added.  The
 139 <tt>try_emit_</tt>* methods in src/mesa/program/ir_to_mesa.cpp and
 140 src/mesa/state_tracker/st_glsl_to_tgsi.cpp can serve as examples.
 141
 142 </ul>
 143
 144
 145 <h2 id="submitting">Submitting patches</h2>
 146
 147 <p>
 148 The basic guidelines for submitting patches are:
 149 </p>
 150
 151 <ul>
 152 <li>Patches should be sufficiently tested before submitting.
 153 <li>Code patches should follow Mesa coding conventions.
 154 <li>Whenever possible, patches should only effect individual Mesa/Gallium
 155 components.
 156 <li>Patches should never introduce build breaks and should be bisectable (see
 157 <code>git bisect</code>.)
 158 <li>Patches should be properly formatted (see below).
 159 <li>Patches should be submitted to mesa-dev for review using
 160 <code>git send-email</code>.
 161 <li>Patches should not mix code changes with code formatting changes (except,
 162 perhaps, in very trivial cases.)
 163 </ul>
 164
 165 <h3>Patch formatting</h3>
 166
 167 <p>
 168 The basic rules for patch formatting are:
 169 </p>
 170
 171 <ul>
 172 <li>Lines should be limited to 75 characters or less so that git logs
 173 displayed in 80-column terminals avoid line wrapping.  Note that git
 174 log uses 4 spaces of indentation (4 + 75 &lt; 80).
 175 <li>The first line should be a short, concise summary of the change prefixed
 176 with a module name.  Examples:
 177 <pre>
 178     mesa: Add support for querying GL_VERTEX_ATTRIB_ARRAY_LONG
 179
 180     gallium: add PIPE_CAP_DEVICE_RESET_STATUS_QUERY
 181
 182     i965: Fix missing type in local variable declaration.
 183 </pre>
 184 <li>Subsequent patch comments should describe the change in more detail,
 185 if needed.  For example:
 186 <pre>
 187     i965: Remove end-of-thread SEND alignment code.
 188
 189     This was present in Eric's initial implementation of the compaction code
 190     for Sandybridge (commit 077d01b6). There is no documentation saying this
 191     is necessary, and removing it causes no regressions in piglit on any
 192     platform.
 193 </pre>
 194 <li>A "Signed-off-by:" line is not required, but not discouraged either.
 195 <li>If a patch address a bugzilla issue, that should be noted in the
 196 patch comment.  For example:
 197 <pre>
 198    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89689
 199 </pre>
 200 <li>If there have been several revisions to a patch during the review
 201 process, they should be noted such as in this example:
 202 <pre>
 203     st/mesa: add ARB_texture_stencil8 support (v4)
 204
 205     if we support stencil texturing, enable texture_stencil8
 206     there is no requirement to support native S8 for this,
 207     the texture can be converted to x24s8 fine.
 208
 209     v2: fold fixes from Marek in:
 210        a) put S8 last in the list
 211        b) fix renderable to always test for d/s renderable
 212         fixup the texture case to use a stencil only format
 213         for picking the format for the texture view.
 214     v3: hit fallback for getteximage
 215     v4: put s8 back in front, it shouldn't get picked now (Ilia)
 216 </pre>
 217 <li>If someone tested your patch, document it with a line like this:
 218 <pre>
 219     Tested-by: Joe Hacker &lt;jhacker@foo.com&gt;
 220 </pre>
 221 <li>If the patch was reviewed (usually the case) or acked by someone,
 222 that should be documented with:
 223 <pre>
 224     Reviewed-by: Joe Hacker &lt;jhacker@foo.com&gt;
 225     Acked-by: Joe Hacker &lt;jhacker@foo.com&gt;
 226 </pre>
 227 </ul>
 228
 229
 230
 231 <h3>Testing Patches</h3>
 232
 233 <p>
 234 It should go without saying that patches must be tested.  In general,
 235 do whatever testing is prudent.
 236 </p>
 237
 238 <p>
 239 You should always run the Mesa test suite before submitting patches.
 240 The test suite can be run using the 'make check' command. All tests
 241 must pass before patches will be accepted, this may mean you have
 242 to update the tests themselves.
 243 </p>
 244
 245 <p>
 246 Whenever possible and applicable, test the patch with
 247 <a href="http://piglit.freedesktop.org">Piglit</a> to
 248 check for regressions.
 249 </p>
 250
 251
 252 <h3>Mailing Patches</h3>
 253
 254 <p>
 255 Patches should be sent to the Mesa mailing list for review.
 256 When submitting a patch make sure to use git send-email rather than attaching
 257 patches to emails. Sending patches as attachments prevents people from being
 258 able to provide in-line review comments.
 259 </p>
 260
 261 <p>
 262 When submitting follow-up patches you can use --in-reply-to to make v2, v3,
 263 etc patches show up as replies to the originals. This usually works well
 264 when you're sending out updates to individual patches (as opposed to
 265 re-sending the whole series). Using --in-reply-to makes
 266 it harder for reviewers to accidentally review old patches.
 267 </p>
 268
 269 <p>
 270 When submitting follow-up patches you should also login to
 271 <a href="https://patchwork.freedesktop.org">patchwork</a> and change the
 272 state of your old patches to Superseded.
 273 </p>
 274
 275 <h3>Reviewing Patches</h3>
 276
 277 <p>
 278 When you've reviewed a patch on the mailing list, please be unambiguous
 279 about your review.  That is, state either
 280 <pre>
 281     Reviewed-by: Joe Hacker &lt;jhacker@foo.com&gt;
 282 </pre>
 283 or
 284 <pre>
 285     Acked-by: Joe Hacker &lt;jhacker@foo.com&gt;
 286 </pre>
 287 Rather than saying just "LGTM" or "Seems OK".
 288 </p>
 289
 290 <p>
 291 If small changes are suggested, it's OK to say something like:
 292 <pre>
 293    With the above fixes, Reviewed-by: Joe Hacker &lt;jhacker@foo.com&gt;
 294 </pre>
 295 which tells the patch author that the patch can be committed, as long
 296 as the issues are resolved first.
 297 </p>
 298
 299
 300 <h3>Marking a commit as a candidate for a stable branch</h3>
 301
 302 <p>
 303 If you want a commit to be applied to a stable branch,
 304 you should add an appropriate note to the commit message.
 305 </p>
 306
 307 <p>
 308 Here are some examples of such a note:
 309 </p>
 310 <ul>
 311   <li>CC: &lt;mesa-stable@lists.freedesktop.org&gt;</li>
 312   <li>CC: "9.2 10.0" &lt;mesa-stable@lists.freedesktop.org&gt;</li>
 313   <li>CC: "10.0" &lt;mesa-stable@lists.freedesktop.org&gt;</li>
 314 </ul>
 315
 316 Simply adding the CC to the mesa-stable list address is adequate to nominate
 317 the commit for the most-recently-created stable branch. It is only necessary
 318 to specify a specific branch name, (such as "9.2 10.0" or "10.0" in the
 319 examples above), if you want to nominate the commit for an older stable
 320 branch. And, as in these examples, you can nominate the commit for the older
 321 branch in addition to the more recent branch, or nominate the commit
 322 exclusively for the older branch.
 323
 324 This "CC" syntax for patch nomination will cause patches to automatically be
 325 copied to the mesa-stable@ mailing list when you use "git send-email" to send
 326 patches to the mesa-dev@ mailing list. Also, if you realize that a commit
 327 should be nominated for the stable branch after it has already been committed,
 328 you can send a note directly to the mesa-stable@lists.freedesktop.org where
 329 the Mesa stable-branch maintainers will receive it. Be sure to mention the
 330 commit ID of the commit of interest (as it appears in the mesa master branch).
 331
 332 The latest set of patches that have been nominated, accepted, or rejected for
 333 the upcoming stable release can always be seen on the
 334 <a href="http://cworth.org/~cworth/mesa-stable-queue/">Mesa Stable Queue</a>
 335 page.
 336
 337 <h3>Criteria for accepting patches to the stable branch</h3>
 338
 339 Mesa has a designated release manager for each stable branch, and the release
 340 manager is the only developer that should be pushing changes to these
 341 branches. Everyone else should simply nominate patches using the mechanism
 342 described above.
 343
 344 The stable-release manager will work with the list of nominated patches, and
 345 for each patch that meets the crtieria below will cherry-pick the patch with:
 346 <code>git cherry-pick -x &lt;commit&gt;</code>. The <code>-x</code> option is
 347 important so that the picked patch references the comit ID of the original
 348 patch.
 349
 350 The stable-release manager may at times need to force-push changes to the
 351 stable branches, for example, to drop a previously-picked patch that was later
 352 identified as causing a regression). These force-pushes may cause changes to
 353 be lost from the stable branch if developers push things directly. Consider
 354 yourself warned.
 355
 356 The stable-release manager is also given broad discretion in rejecting patches
 357 that have been nominated for the stable branch. The most basic rule is that
 358 the stable branch is for bug fixes only, (no new features, no
 359 regressions). Here is a non-exhaustive list of some reasons that a patch may
 360 be rejected:
 361
 362 <ul>
 363   <li>Patch introduces a regression. Any reported build breakage or other
 364   regression caused by a particular patch, (game no longer work, piglit test
 365   changes from PASS to FAIL), is justification for rejecting a patch.</li>
 366
 367   <li>Patch is too large, (say, larger than 100 lines)</li>
 368
 369   <li>Patch is not a fix. For example, a commit that moves code around with no
 370   functional change should be rejected.</li>
 371
 372   <li>Patch fix is not clearly described. For example, a commit message
 373   of only a single line, no description of the bug, no mention of bugzilla,
 374   etc.</li>
 375
 376   <li>Patch has not obviously been reviewed, For example, the commit message
 377   has no Reviewed-by, Signed-off-by, nor Tested-by tags from anyone but the
 378   author.</li>
 379
 380   <li>Patch has not already been merged to the master branch. As a rule, bug
 381   fixes should never be applied first to a stable branch. Patches should land
 382   first on the master branch and then be cherry-picked to a stable
 383   branch. (This is to avoid future releases causing regressions if the patch
 384   is not also applied to master.) The only things that might look like
 385   exceptions would be backports of patches from master that happen to look
 386   significantly different.</li>
 387
 388   <li>Patch depends on too many other patches. Ideally, all stable-branch
 389   patches should be self-contained. It sometimes occurs that a single, logical
 390   bug-fix occurs as two separate patches on master, (such as an original
 391   patch, then a subsequent fix-up to that patch). In such a case, these two
 392   patches should be squashed into a single, self-contained patch for the
 393   stable branch. (Of course, if the squashing makes the patch too large, then
 394   that could be a reason to reject the patch.)</li>
 395
 396   <li>Patch includes new feature development, not bug fixes. New OpenGL
 397   features, extensions, etc. should be applied to Mesa master and included in
 398   the next major release. Stable releases are intended only for bug fixes.
 399
 400   Note: As an exception to this rule, the stable-release manager may accept
 401   hardware-enabling "features". For example, backports of new code to support
 402   a newly-developed hardware product can be accepted if they can be reasonably
 403   determined to not have effects on other hardware.</li>
 404
 405   <li>Patch is a performance optimization. As a rule, performance patches are
 406   not candidates for the stable branch. The only exception might be a case
 407   where an application's performance was recently severely impacted so as to
 408   become unusable. The fix for this performance regression could then be
 409   considered for a stable branch. The optimization must also be
 410   non-controversial and the patches still need to meet the other criteria of
 411   being simple and self-contained</li>
 412
 413   <li>Patch introduces a new failure mode (such as an assert). While the new
 414   assert might technically be correct, for example to make Mesa more
 415   conformant, this is not the kind of "bug fix" we want in a stable
 416   release. The potential problem here is that an OpenGL program that was
 417   previously working, (even if technically non-compliant with the
 418   specification), could stop working after this patch. So that would be a
 419   regression that is unaacceptable for the stable branch.</li>
 420 </ul>
 421
 422
 423 <h2 id="release">Making a New Mesa Release</h2>
 424
 425 <p>
 426 These are the instructions for making a new Mesa release.
 427 </p>
 428
 429 <h3>Get latest source files</h3>
 430 <p>
 431 Use git to get the latest Mesa files from the git repository, from whatever
 432 branch is relevant. This document uses the convention X.Y.Z for the release
 433 being created, which should be created from a branch named X.Y.
 434 </p>
 435
 436 <h3>Perform basic testing</h3>
 437 <p>
 438 The release manager should, at the very least, test the code by compiling it,
 439 installing it, and running the latest piglit to ensure that no piglit tests
 440 have regressed since the previous release.
 441 </p>
 442
 443 <p>
 444 The release manager should do this testing with at least one hardware driver,
 445 (say, whatever is contained in the local development machine), as well as on
 446 both Gallium and non-Gallium software drivers. The software testing can be
 447 performed by running piglit with the following environment-variable set:
 448 </p>
 449
 450 <pre>
 451 LIBGL_ALWAYS_SOFTWARE=1
 452 </pre>
 453
 454 And Gallium vs. non-Gallium software drivers can be obtained by using the
 455 following configure flags on separate builds:
 456
 457 <pre>
 458 --with-dri-drivers=swrast
 459 --with-gallium-drivers=swrast
 460 </pre>
 461
 462 <p>
 463 Note: If both options are given in one build, both swrast_dri.so drivers will
 464 be compiled, but only one will be installed. The following command can be used
 465 to ensure the correct driver is being tested:
 466 </p>
 467
 468 <pre>
 469 LIBGL_ALWAYS_SOFTWARE=1 glxinfo | grep "renderer string"
 470 </pre>
 471
 472 If any regressions are found in this testing with piglit, stop here, and do
 473 not perform a release until regressions are fixed.
 474
 475 <h3>Update version in file VERSION</h3>
 476
 477 <p>
 478 Increment the version contained in the file VERSION at Mesa's top-level, then
 479 commit this change.
 480 </p>
 481
 482 <h3>Create release notes for the new release</h3>
 483
 484 <p>
 485 Create a new file docs/relnotes/X.Y.Z.html, (follow the style of the previous
 486 release notes). Note that the sha256sums section of the release notes should
 487 be empty at this point.
 488 </p>
 489
 490 <p>
 491 Two scripts are available to help generate portions of the release notes:
 492
 493 <pre>
 494         ./bin/bugzilla_mesa.sh
 495         ./bin/shortlog_mesa.sh
 496 </pre>
 497
 498 <p>
 499 The first script identifies commits that reference bugzilla bugs and obtains
 500 the descriptions of those bugs from bugzilla. The second script generates a
 501 log of all commits. In both cases, HTML-formatted lists are printed to stdout
 502 to be included in the release notes.
 503 </p>
 504
 505 <p>
 506 Commit these changes
 507 </p>
 508
 509 <h3>Make the release archives, signatures, and the release tag</h3>
 510 <p>
 511 From inside the Mesa directory:
 512 <pre>
 513         ./autogen.sh
 514         make -j1 tarballs
 515 </pre>
 516
 517 <p>
 518 After the tarballs are created, the sha256 checksums for the files will
 519 be computed and printed. These will be used in a step below.
 520 </p>
 521
 522 <p>
 523 It's important at this point to also verify that the constructed tar file
 524 actually builds:
 525 </p>
 526
 527 <pre>
 528         tar xjf MesaLib-X.Y.Z.tar.bz2
 529         cd Mesa-X.Y.Z
 530         ./configure --enable-gallium-llvm
 531         make -j6
 532         make install
 533 </pre>
 534
 535 <p>
 536 Some touch testing should also be performed at this point, (run glxgears or
 537 more involved OpenGL programs against the installed Mesa).
 538 </p>
 539
 540 <p>
 541 Create detached GPG signatures for each of the archive files created above:
 542 </p>
 543
 544 <pre>
 545         gpg --sign --detach MesaLib-X.Y.Z.tar.gz
 546         gpg --sign --detach MesaLib-X.Y.Z.tar.bz2
 547         gpg --sign --detach MesaLib-X.Y.Z.zip
 548 </pre>
 549
 550 <p>
 551 Tag the commit used for the build:
 552 </p>
 553
 554 <pre>
 555         git tag -s mesa-X.Y.X -m "Mesa X.Y.Z release"
 556 </pre>
 557
 558 <p>
 559 Note: It would be nice to investigate and fix the issue that causes the
 560 tarballs target to fail with multiple build process, such as with "-j4". It
 561 would also be nice to incorporate all of the above commands into a single
 562 makefile target. And instead of a custom "tarballs" target, we should
 563 incorporate things into the standard "make dist" and "make distcheck" targets.
 564 </p>
 565
 566 <h3>Add the sha256sums to the release notes</h3>
 567
 568 <p>
 569 Edit docs/relnotes/X.Y.Z.html to add the sha256sums printed as part of "make
 570 tarballs" in the previous step. Commit this change.
 571 </p>
 572
 573 <h3>Push all commits and the tag created above</h3>
 574
 575 <p>
 576 This is the first step that cannot easily be undone. The release is going
 577 forward from this point:
 578 </p>
 579
 580 <pre>
 581         git push origin X.Y --tags
 582 </pre>
 583
 584 <h3>Install the release files and signatures on the distribution server</h3>
 585
 586 <p>
 587 The following commands can be used to copy the release archive files and
 588 signatures to the freedesktop.org server:
 589 </p>
 590
 591 <pre>
 592         scp MesaLib-X.Y.Z* people.freedesktop.org:
 593         ssh people.freedesktop.org
 594         cd /srv/ftp.freedesktop.org/pub/mesa
 595         mkdir X.Y.Z
 596         cd X.Y.Z
 597         mv ~/MesaLib-X.Y.Z* .
 598 </pre>
 599
 600 <h3>Back on mesa master, add the new release notes into the tree</h3>
 601
 602 <p>
 603 Something like the following steps will do the trick:
 604 </p>
 605
 606 <pre>
 607         cp docs/relnotes/X.Y.Z.html /tmp
 608         git checkout master
 609         cp /tmp/X.Y.Z.html docs/relnotes
 610         git add docs/relnotes/X.Y.Z.html
 611 </pre>
 612
 613 <p>
 614 Also, edit docs/relnotes.html to add a link to the new release notes, and edit
 615 docs/index.html to add a news entry. Then commit and push:
 616 </p>
 617
 618 <pre>
 619         git commit -a -m "docs: Import X.Y.Z release notes, add news item."
 620         git push origin
 621 </pre>
 622
 623 <h3>Update the mesa3d.org website</h3>
 624
 625 <p>
 626 NOTE: The recent release managers have not been performing this step
 627 themselves, but leaving this to Brian Paul, (who has access to the
 628 sourceforge.net hosting for mesa3d.org). Brian is more than willing to grant
 629 the permission necessary to future release managers to do this step on their
 630 own.
 631 </p>
 632
 633 <p>
 634 Update the web site by copying the docs/ directory's files to
 635 /home/users/b/br/brianp/mesa-www/htdocs/ with:
 636 <br>
 637 <code>
 638 sftp USERNAME,mesa3d@web.sourceforge.net
 639 </code>
 640 </p>
 641
 642
 643 <h3>Announce the release</h3>
 644 <p>
 645 Make an announcement on the mailing lists:
 646
 647 <em>mesa-dev@lists.freedesktop.org</em>,
 648 and
 649 <em>mesa-announce@lists.freedesktop.org</em>
 650
 651 Follow the template of previously-sent release announcements. The following
 652 command can be used to generate the log of changes to be included in the
 653 release announcement:
 654
 655 <pre>
 656         git shortlog mesa-X.Y.Z-1..mesa-X.Y.Z
 657 </pre>
 658 </p>
 659
 660
 661 <h2 id="extensions">Adding Extensions</h2>
 662
 663 <p>
 664 To add a new GL extension to Mesa you have to do at least the following.
 665
 666 <ul>
 667 <li>
 668    If glext.h doesn't define the extension, edit include/GL/gl.h and add
 669    code like this:
 670    <pre>
 671      #ifndef GL_EXT_the_extension_name
 672      #define GL_EXT_the_extension_name 1
 673      /* declare the new enum tokens */
 674      /* prototype the new functions */
 675      /* TYPEDEFS for the new functions */
 676      #endif
 677    </pre>
 678 </li>
 679 <li>
 680    In the src/mapi/glapi/gen/ directory, add the new extension functions and
 681    enums to the gl_API.xml file.
 682    Then, a bunch of source files must be regenerated by executing the
 683    corresponding Python scripts.
 684 </li>
 685 <li>
 686    Add a new entry to the <code>gl_extensions</code> struct in mtypes.h
 687 </li>
 688 <li>
 689    Update the <code>extensions.c</code> file.
 690 </li>
 691 <li>
 692    From this point, the best way to proceed is to find another extension,
 693    similar to the new one, that's already implemented in Mesa and use it
 694    as an example.
 695 </li>
 696 <li>
 697    If the new extension adds new GL state, the functions in get.c, enable.c
 698    and attrib.c will most likely require new code.
 699 </li>
 700 <li>
 701    The dispatch tests check_table.cpp and dispatch_sanity.cpp
 702    should be updated with details about the new extensions functions. These
 703    tests are run using 'make check'
 704 </li>
 705 </ul>
 706
 707
 708
 709
 710 </div>
 711 </body>
 712 </html>