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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/mesa/glapi/ 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
 159 <h2>Marking a commit as a candidate for a stable branch</h2>
 160
 161 <p>
 162 If you want a commit to be applied to a stable branch,
 163 you should add an appropriate note to the commit message.
 164 </p>
 165
 166 <p>
 167 Here are some examples of such a note:
 168 </p>
 169 <ul>
 170   <li>NOTE: This is a candidate for the 9.0 branch.</li>
 171   <li>NOTE: This is a candidate for the 8.0 and 9.0 branches.</li>
 172   <li>NOTE: This is a candidate for the stable branches.</li>
 173 </ul>
 174
 175
 176 <h2>Cherry-picking candidates for a stable branch</h2>
 177
 178 <p>
 179 Please use <code>git cherry-pick -x &lt;commit&gt;</code> for cherry-picking a commit
 180 from master to a stable branch.
 181 </p>
 182
 183 <h2>Making a New Mesa Release</h2>
 184
 185 <p>
 186 These are the instructions for making a new Mesa release.
 187 </p>
 188
 189 <h3>Get latest source files</h3>
 190 <p>
 191 Use git to get the latest Mesa files from the git repository, from whatever
 192 branch is relevant.
 193 </p>
 194
 195
 196 <h3>Verify and update version info</h3>
 197
 198 <dl>
 199   <dt>SConstruct</dt>
 200   <dt>Android.common.mk</dt>
 201   <dd>PACKAGE_VERSION</dd>
 202   <dt>configure.ac</dt>
 203   <dd>AC_INIT</dd>
 204 </dl>
 205
 206 <p>
 207 Create a docs/relnotes/x.y.z.html file.
 208 The bin/bugzilla_mesa.sh and bin/shortlog_mesa.sh scripts can be used to
 209 create the HTML-formatted lists of bugfixes and changes to include in the file.
 210 Link the new docs/relnotes/x.y.z.html file into the main <a href="relnotes.html">relnotes.html</a> file.
 211 </p>
 212
 213 <p>
 214 Update <a href="index.html">docs/index.html</a>.
 215 </p>
 216
 217 <p>
 218 Tag the files with the release name (in the form <b>mesa-x.y</b>)
 219 with: <code>git tag -s mesa-x.y -m "Mesa x.y Release"</code>
 220 Then: <code>git push origin mesa-x.y</code>
 221 </p>
 222
 223
 224 <h3>Make the tarballs</h3>
 225 <p>
 226 Make the distribution files.  From inside the Mesa directory:
 227 <pre>
 228         ./autogen.sh
 229         make tarballs
 230 </pre>
 231
 232 <p>
 233 After the tarballs are created, the md5 checksums for the files will
 234 be computed.
 235 Add them to the docs/relnotes/x.y.html file.
 236 </p>
 237
 238 <p>
 239 Copy the distribution files to a temporary directory, unpack them,
 240 compile everything, and run some demos to be sure everything works.
 241 </p>
 242
 243 <h3>Update the website and announce the release</h3>
 244 <p>
 245 Make a new directory for the release on annarchy.freedesktop.org with:
 246 <br>
 247 <code>
 248 mkdir /srv/ftp.freedesktop.org/pub/mesa/x.y
 249 </code>
 250 </p>
 251
 252 <p>
 253 Basically, to upload the tarball files with:
 254 <br>
 255 <code>
 256 rsync -avP -e ssh MesaLib-x.y.* USERNAME@annarchy.freedesktop.org:/srv/ftp.freedesktop.org/pub/mesa/x.y/
 257 </code>
 258 </p>
 259
 260 <p>
 261 Update the web site by copying the docs/ directory's files to
 262 /home/users/b/br/brianp/mesa-www/htdocs/ with:
 263 <br>
 264 <code>
 265 sftp USERNAME,mesa3d@web.sourceforge.net
 266 </code>
 267 </p>
 268
 269 <p>
 270 Make an announcement on the mailing lists:
 271
 272 <em>mesa-dev@lists.freedesktop.org</em>,
 273 <em>mesa-users@lists.freedesktop.org</em>
 274 and
 275 <em>mesa-announce@lists.freedesktop.org</em>
 276 </p>
 277
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