third_party_mesa3d/docs/application-issues.html
Erik Faye-Lund 392c083377 docs: add more more code-tags
It's easier to read function-names, file-names and other
"machine"-related strings if they are formatted in a monospace font. So
let's mark these up with code-tags.

Signed-off-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>
2019-06-05 23:48:44 +02:00

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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<title>Application Issues</title>
<link rel="stylesheet" type="text/css" href="mesa.css">
</head>
<body>
<div class="header">
The Mesa 3D Graphics Library
</div>
<iframe src="contents.html"></iframe>
<div class="content">
<h1>Application Issues</h1>
<p>
This page documents known issues with some OpenGL applications.
</p>
<h2>Topogun</h2>
<p>
<a href="http://www.topogun.com/">Topogun</a> for Linux (version 2, at least)
creates a GLX visual without requesting a depth buffer.
This causes bad rendering if the OpenGL driver happens to choose a visual
without a depth buffer.
</p>
<p>
Mesa 9.1.2 and later (will) support a DRI configuration option to work around
this issue.
Using the <a href="https://dri.freedesktop.org/wiki/DriConf">driconf</a> tool,
set the "Create all visuals with a depth buffer" option before running Topogun.
Then, all GLX visuals will be created with a depth buffer.
</p>
<h2>Old OpenGL games</h2>
<p>
Some old OpenGL games (approx. ten years or older) may crash during
start-up because of an extension string buffer-overflow problem.
</p>
<p>
The problem is a modern OpenGL driver will return a very long string
for the <code>glGetString(GL_EXTENSIONS)</code> query and if the application
naively copies the string into a fixed-size buffer it can overflow the
buffer and crash the application.
</p>
<p>
The work-around is to set the <code>MESA_EXTENSION_MAX_YEAR</code>
environment variable to the approximate release year of the game.
This will cause the <code>glGetString(GL_EXTENSIONS)</code> query to only report
extensions older than the given year.
</p>
<p>
For example, if the game was released in 2001, do
</p>
<pre>
export MESA_EXTENSION_MAX_YEAR=2001
</pre>
<p>
before running the game.
</p>
<h2>Viewperf</h2>
<p>
See the <a href="viewperf.html">Viewperf issues</a> page for a detailed list
of Viewperf issues.
</p>
</div>
</body>
</html>