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  10 <div class="header">
  11   <h1>The Mesa 3D Graphics Library</h1>
  12 </div>
  13
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  15 <div class="content">
  16
  17 <h1>Development Notes</h1>
  18
  19
  20 <h2>Adding Extentions</h2>
  21
  22 <p>
  23 To add a new GL extension to Mesa you have to do at least the following.
  24
  25 <ul>
  26 <li>
  27    If glext.h doesn't define the extension, edit include/GL/gl.h and add
  28    code like this:
  29    <pre>
  30      #ifndef GL_EXT_the_extension_name
  31      #define GL_EXT_the_extension_name 1
  32      /* declare the new enum tokens */
  33      /* prototype the new functions */
  34      /* TYPEDEFS for the new functions */
  35      #endif
  36    </pre>
  37 </li>
  38 <li>
  39    In the src/mapi/glapi/gen/ directory, add the new extension functions and
  40    enums to the gl_API.xml file.
  41    Then, a bunch of source files must be regenerated by executing the
  42    corresponding Python scripts.
  43 </li>
  44 <li>
  45    Add a new entry to the <code>gl_extensions</code> struct in mtypes.h
  46 </li>
  47 <li>
  48    Update the <code>extensions.c</code> file.
  49 </li>
  50 <li>
  51    From this point, the best way to proceed is to find another extension,
  52    similar to the new one, that's already implemented in Mesa and use it
  53    as an example.
  54 </li>
  55 <li>
  56    If the new extension adds new GL state, the functions in get.c, enable.c
  57    and attrib.c will most likely require new code.
  58 </li>
  59 </ul>
  60
  61
  62
  63 <h2>Coding Style</h2>
  64
  65 <p>
  66 Mesa's code style has changed over the years.  Here's the latest.
  67 </p>
  68
  69 <p>
  70 Comment your code!  It's extremely important that open-source code be
  71 well documented.  Also, strive to write clean, easily understandable code.
  72 </p>
  73
  74 <p>
  75 3-space indentation
  76 </p>
  77
  78 <p>
  79 If you use tabs, set them to 8 columns
  80 </p>
  81
  82 <p>
  83 Line width: the preferred width to fill comments and code in Mesa is 78
  84 columns.  Exceptions are sometimes made for clarity (e.g. tabular data is
  85 sometimes filled to a much larger width so that extraneous carriage returns
  86 don't obscure the table).
  87 </p>
  88
  89 <p>
  90 Brace example:
  91 </p>
  92 <pre>
  93         if (condition) {
  94            foo;
  95         }
  96         else {
  97            bar;
  98         }
  99
 100         switch (condition) {
 101         case 0:
 102            foo();
 103            break;
 104
 105         case 1: {
 106            ...
 107            break;
 108         }
 109
 110         default:
 111            ...
 112            break;
 113         }
 114 </pre>
 115
 116 <p>
 117 Here's the GNU indent command which will best approximate my preferred style:
 118 (Note that it won't format switch statements in the preferred way)
 119 </p>
 120 <pre>
 121         indent -br -i3 -npcs --no-tabs infile.c -o outfile.c
 122 </pre>
 123
 124
 125 <p>
 126 Local variable name example:  localVarName (no underscores)
 127 </p>
 128
 129 <p>
 130 Constants and macros are ALL_UPPERCASE, with _ between words
 131 </p>
 132
 133 <p>
 134 Global variables are not allowed.
 135 </p>
 136
 137 <p>
 138 Function name examples:
 139 </p>
 140 <pre>
 141         glFooBar()       - a public GL entry point (in glapi_dispatch.c)
 142         _mesa_FooBar()   - the internal immediate mode function
 143         save_FooBar()    - retained mode (display list) function in dlist.c
 144         foo_bar()        - a static (private) function
 145         _mesa_foo_bar()  - an internal non-static Mesa function
 146 </pre>
 147
 148 <p>
 149 Places that are not directly visible to the GL API should prefer the use
 150 of <tt>bool</tt>, <tt>true</tt>, and
 151 <tt>false</tt> over <tt>GLboolean</tt>, <tt>GL_TRUE</tt>, and
 152 <tt>GL_FALSE</tt>.  In C code, this may mean that
 153 <tt>#include &lt;stdbool.h&gt;</tt> needs to be added.  The
 154 <tt>try_emit_</tt>* methods in src/mesa/program/ir_to_mesa.cpp and
 155 src/mesa/state_tracker/st_glsl_to_tgsi.cpp can serve as examples.
 156 </p>
 157
 158 <h2>Submitting patches</h2>
 159
 160 <p>
 161 You should always run the Mesa Testsuite before submitting patches.
 162 The Testsuite can be run using the 'make check' command. All tests
 163 must pass before patches will be accepted, this may mean you have
 164 to update the tests themselves.
 165 </p>
 166
 167 <p>
 168 Patches should be sent to the Mesa mailing list for review.
 169 When submitting a patch make sure to use git send-email rather than attaching
 170 patches to emails. Sending patches as attachments prevents people from being
 171 able to provide in-line review comments.
 172 </p>
 173
 174 <p>
 175 When submitting follow-up patches you can use --in-reply-to to make v2, v3,
 176 etc patches show up as replies to the originals. This usually works well
 177 when you're sending out updates to individual patches (as opposed to
 178 re-sending the whole series). Using --in-reply-to makes
 179 it harder for reviewers to accidentally review old patches.
 180 </p>
 181
 182 <h2>Marking a commit as a candidate for a stable branch</h2>
 183
 184 <p>
 185 If you want a commit to be applied to a stable branch,
 186 you should add an appropriate note to the commit message.
 187 </p>
 188
 189 <p>
 190 Here are some examples of such a note:
 191 </p>
 192 <ul>
 193   <li>NOTE: This is a candidate for the 9.0 branch.</li>
 194   <li>NOTE: This is a candidate for the 8.0 and 9.0 branches.</li>
 195   <li>NOTE: This is a candidate for the stable branches.</li>
 196 </ul>
 197
 198
 199 <h2>Cherry-picking candidates for a stable branch</h2>
 200
 201 <p>
 202 Please use <code>git cherry-pick -x &lt;commit&gt;</code> for cherry-picking a commit
 203 from master to a stable branch.
 204 </p>
 205
 206 <h2>Making a New Mesa Release</h2>
 207
 208 <p>
 209 These are the instructions for making a new Mesa release.
 210 </p>
 211
 212 <h3>Get latest source files</h3>
 213 <p>
 214 Use git to get the latest Mesa files from the git repository, from whatever
 215 branch is relevant.
 216 </p>
 217
 218
 219 <h3>Verify and update version info in VERSION</h3>
 220
 221 <p>
 222 Create a docs/relnotes/x.y.z.html file.
 223 The bin/bugzilla_mesa.sh and bin/shortlog_mesa.sh scripts can be used to
 224 create the HTML-formatted lists of bugfixes and changes to include in the file.
 225 Link the new docs/relnotes/x.y.z.html file into the main <a href="relnotes.html">relnotes.html</a> file.
 226 </p>
 227
 228 <p>
 229 Update <a href="index.html">docs/index.html</a>.
 230 </p>
 231
 232 <p>
 233 Tag the files with the release name (in the form <b>mesa-x.y</b>)
 234 with: <code>git tag -s mesa-x.y -m "Mesa x.y Release"</code>
 235 Then: <code>git push origin mesa-x.y</code>
 236 </p>
 237
 238
 239 <h3>Make the tarballs</h3>
 240 <p>
 241 Make the distribution files.  From inside the Mesa directory:
 242 <pre>
 243         ./autogen.sh
 244         make tarballs
 245 </pre>
 246
 247 <p>
 248 After the tarballs are created, the md5 checksums for the files will
 249 be computed.
 250 Add them to the docs/relnotes/x.y.html file.
 251 </p>
 252
 253 <p>
 254 Copy the distribution files to a temporary directory, unpack them,
 255 compile everything, and run some demos to be sure everything works.
 256 </p>
 257
 258 <h3>Update the website and announce the release</h3>
 259 <p>
 260 Make a new directory for the release on annarchy.freedesktop.org with:
 261 <br>
 262 <code>
 263 mkdir /srv/ftp.freedesktop.org/pub/mesa/x.y
 264 </code>
 265 </p>
 266
 267 <p>
 268 Basically, to upload the tarball files with:
 269 <br>
 270 <code>
 271 rsync -avP -e ssh MesaLib-x.y.* USERNAME@annarchy.freedesktop.org:/srv/ftp.freedesktop.org/pub/mesa/x.y/
 272 </code>
 273 </p>
 274
 275 <p>
 276 Update the web site by copying the docs/ directory's files to
 277 /home/users/b/br/brianp/mesa-www/htdocs/ with:
 278 <br>
 279 <code>
 280 sftp USERNAME,mesa3d@web.sourceforge.net
 281 </code>
 282 </p>
 283
 284 <p>
 285 Make an announcement on the mailing lists:
 286
 287 <em>mesa-dev@lists.freedesktop.org</em>,
 288 <em>mesa-users@lists.freedesktop.org</em>
 289 and
 290 <em>mesa-announce@lists.freedesktop.org</em>
 291 </p>
 292
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