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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 <h2>Making a New Mesa Release</h2>
 176
 177 <p>
 178 These are the instructions for making a new Mesa release.
 179 </p>
 180
 181 <h3>Get latest source files</h3>
 182 <p>
 183 Use git to get the latest Mesa files from the git repository, from whatever
 184 branch is relevant.
 185 </p>
 186
 187
 188 <h3>Verify and update version info</h3>
 189
 190 <dl>
 191   <dt>configs/default</dt>
 192   <dd>MESA_MAJOR, MESA_MINOR and MESA_TINY</dd>
 193   <dt>Makefile.am</dt>
 194   <dd>PACKAGE_VERSION</dd>
 195   <dt>configure.ac</dt>
 196   <dd>AC_INIT</dd>
 197   <dt>src/mesa/main/version.h</dt>
 198   <dd>MESA_MAJOR, MESA_MINOR, MESA_PATCH and MESA_VERSION_STRING</dd>
 199 </dl>
 200
 201 <p>
 202 Create a docs/relnotes-x.y.z.html file.
 203 The bin/shortlog_mesa.sh script can be used to create a HTML-formatted list
 204 of changes to include in the file.
 205 Link the new docs/relnotes-x.y.z.html file into the main <a href="relnotes.html">relnotes.html</a> file.
 206 </p>
 207
 208 <p>
 209 Update <a href="index.html">docs/index.html</a>.
 210 </p>
 211
 212 <p>
 213 Tag the files with the release name (in the form <b>mesa-x.y</b>)
 214 with: <code>git tag -a mesa-x.y</code>
 215 Then: <code>git push origin mesa-x.y</code>
 216 </p>
 217
 218
 219 <h3>Make the tarballs</h3>
 220 <p>
 221 Make the distribution files.  From inside the Mesa directory:
 222 <pre>
 223         make tarballs
 224 </pre>
 225
 226 <p>
 227 After the tarballs are created, the md5 checksums for the files will
 228 be computed.
 229 Add them to the docs/relnotes-x.y.html file.
 230 </p>
 231
 232 <p>
 233 Copy the distribution files to a temporary directory, unpack them,
 234 compile everything, and run some demos to be sure everything works.
 235 </p>
 236
 237 <h3>Update the website and announce the release</h3>
 238 <p>
 239 Follow the directions on SourceForge for creating a new "release" and
 240 uploading the tarballs.
 241 </p>
 242
 243 <p>
 244 Basically, to upload the tarball files with:
 245 <br>
 246 <code>
 247 rsync -avP ssh Mesa*-X.Y.* USERNAME@frs.sourceforge.net:uploads/
 248 </code>
 249 </p>
 250
 251 <p>
 252 Update the web site by copying the docs/ directory's files to
 253 /home/users/b/br/brianp/mesa-www/htdocs/ with:
 254 <br>
 255 <code>
 256 sftp USERNAME,mesa3d@web.sourceforge.net
 257 </code>
 258 </p>
 259
 260 <p>
 261 Make an announcement on the mailing lists:
 262
 263 <em>m</em><em>e</em><em>s</em><em>a</em><em>-</em><em>d</em><em>e</em><em>v</em><em>@</em><em>l</em><em>i</em><em>s</em><em>t</em><em>s</em><em>.</em><em>f</em><em>r</em><em>e</em><em>e</em><em>d</em><em>e</em><em>s</em><em>k</em><em>t</em><em>o</em><em>p</em><em>.</em><em>o</em><em>r</em><em>g</em>,
 264 <em>m</em><em>e</em><em>s</em><em>a</em><em>-</em><em>u</em><em>s</em><em>e</em><em>r</em><em>s</em><em>@</em><em>l</em><em>i</em><em>s</em><em>t</em><em>s</em><em>.</em><em>f</em><em>r</em><em>e</em><em>e</em><em>d</em><em>e</em><em>s</em><em>k</em><em>t</em><em>o</em><em>p</em><em>.</em><em>o</em><em>r</em><em>g</em>
 265 and
 266 <em>m</em><em>e</em><em>s</em><em>a</em><em>-</em><em>a</em><em>n</em><em>n</em><em>o</em><em>u</em><em>n</em><em>c</em><em>e</em><em>@</em><em>l</em><em>i</em><em>s</em><em>t</em><em>s</em><em>.</em><em>f</em><em>r</em><em>e</em><em>e</em><em>d</em><em>e</em><em>s</em><em>k</em><em>t</em><em>o</em><em>p</em><em>.</em><em>o</em><em>r</em><em>g</em>
 267 </p>
 268
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