1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html lang="en"> 3<head> 4 <meta http-equiv="content-type" content="text/html; charset=utf-8"> 5 <title>Application Issues</title> 6 <link rel="stylesheet" type="text/css" href="mesa.css"> 7</head> 8<body> 9 10<div class="header"> 11 <h1>The Mesa 3D Graphics Library</h1> 12</div> 13 14<iframe src="contents.html"></iframe> 15<div class="content"> 16 17<h1>Application Issues</h1> 18 19<p> 20This 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) 28creates a GLX visual without requesting a depth buffer. 29This causes bad rendering if the OpenGL driver happens to choose a visual 30without a depth buffer. 31</p> 32 33<p> 34Mesa 9.1.2 and later (will) support a DRI configuration option to work around 35this issue. 36Using the <a href="http://dri.freedesktop.org/wiki/DriConf">driconf</a> tool, 37set the "Create all visuals with a depth buffer" option before running Topogun. 38Then, all GLX visuals will be created with a depth buffer. 39</p> 40 41 42<h2>Old OpenGL games</h2> 43 44<p> 45Some old OpenGL games (approx. ten years or older) may crash during 46start-up because of an extension string buffer-overflow problem. 47</p> 48 49<p> 50The problem is a modern OpenGL driver will return a very long string 51for the glGetString(GL_EXTENSIONS) query and if the application 52naively copies the string into a fixed-size buffer it can overflow the 53buffer and crash the application. 54</p> 55 56<p> 57The work-around is to set the MESA_EXTENSION_MAX_YEAR environment variable 58to the approximate release year of the game. 59This will cause the glGetString(GL_EXTENSIONS) query to only report extensions 60older than the given year. 61</p> 62 63<p> 64For example, if the game was released in 2001, do 65<pre> 66export MESA_EXTENSION_MAX_YEAR=2001 67</pre> 68before running the game. 69</p> 70 71 72 73<h2>Viewperf</h2> 74 75<p> 76See the <a href="viewperf.html">Viewperf issues</a> page for a detailed list 77of Viewperf issues. 78</p> 79 80 81</div> 82</body> 83</html> 84