docs/application-issues.html

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  11   <h1>The Mesa 3D Graphics Library</h1>
  12 </div>
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  16
  17 <h1>Application Issues</h1>
  18
  19 <p>
  20 This page documents known issues with some OpenGL applications.
  21 </p>
  22
  23
  24 <h2>Topogun</h2>
  25
  26 <p>
  27 <a href="http://www.topogun.com/">Topogun</a> for Linux (version 2, at least)
  28 creates a GLX visual without requesting a depth buffer.
  29 This causes bad rendering if the OpenGL driver happens to choose a visual
  30 without a depth buffer.
  31 </p>
  32
  33 <p>
  34 Mesa 9.1.2 and later (will) support a DRI configuration option to work around
  35 this issue.
  36 Using the <a href="https://dri.freedesktop.org/wiki/DriConf">driconf</a> tool,
  37 set the "Create all visuals with a depth buffer" option before running Topogun.
  38 Then, all GLX visuals will be created with a depth buffer.
  39 </p>
  40
  41
  42 <h2>Old OpenGL games</h2>
  43
  44 <p>
  45 Some old OpenGL games (approx. ten years or older) may crash during
  46 start-up because of an extension string buffer-overflow problem.
  47 </p>
  48
  49 <p>
  50 The problem is a modern OpenGL driver will return a very long string
  51 for the glGetString(GL_EXTENSIONS) query and if the application
  52 naively copies the string into a fixed-size buffer it can overflow the
  53 buffer and crash the application.
  54 </p>
  55
  56 <p>
  57 The work-around is to set the MESA_EXTENSION_MAX_YEAR environment variable
  58 to the approximate release year of the game.
  59 This will cause the glGetString(GL_EXTENSIONS) query to only report extensions
  60 older than the given year.
  61 </p>
  62
  63 <p>
  64 For example, if the game was released in 2001, do
  65 <pre>
  66 export MESA_EXTENSION_MAX_YEAR=2001
  67 </pre>
  68 before running the game.
  69 </p>
  70
  71
  72
  73 <h2>Viewperf</h2>
  74
  75 <p>
  76 See the <a href="viewperf.html">Viewperf issues</a> page for a detailed list
  77 of Viewperf issues.
  78 </p>
  79
  80
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