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>OpenGL ES</title> 6 <link rel="stylesheet" type="text/css" href="mesa.css"> 7</head> 8<body> 9 10<h1>OpenGL ES</h1> 11 12<p>Mesa implements OpenGL ES 1.1 and OpenGL ES 2.0. More informations about 13OpenGL ES can be found at <a href="http://www.khronos.org/opengles/" 14target="_parent"> http://www.khronos.org/opengles/</a>.</p> 15 16<p>OpenGL ES depends on a working EGL implementation. Please refer to 17<a href="egl.html">Mesa EGL</a> for more information about EGL.</p> 18 19<h2>Build the Libraries</h2> 20<ol> 21<li>Run <code>configure</code> with <code>--enable-gles1 --enable-gles2</code> and enable the Gallium driver for your hardware.</li> 22<li>Build and install Mesa as usual.</li> 23</ol> 24 25Alternatively, if XCB-DRI2 is installed on the system, one can use 26<code>egl_dri2</code> EGL driver with OpenGL|ES-enabled DRI drivers 27 28<ol> 29<li>Run <code>configure</code> with <code>--enable-gles1 --enable-gles2</code>.</li> 30<li>Build and install Mesa as usual.</li> 31</ol> 32 33<p>Both methods will install libGLESv1_CM, libGLESv2, libEGL, and one or more 34EGL drivers for your hardware.</p> 35 36<h2>Run the Demos</h2> 37 38<p>There are some demos in <code>mesa/demos</code> repository.</p> 39 40<h2>Developers</h2> 41 42<h3>Dispatch Table</h3> 43 44<p>OpenGL ES has an additional indirection when dispatching fucntions</p> 45 46<pre> 47 Mesa: glFoo() --> _mesa_Foo() 48 OpenGL ES: glFoo() --> _es_Foo() --> _mesa_Foo() 49</pre> 50 51<p>The indirection serves several purposes</p> 52 53<ul> 54<li>When a function is in Mesa and the type matches, it checks the arguments and calls the Mesa function.</li> 55<li>When a function is in Mesa but the type mismatches, it checks and converts the arguments before calling the Mesa function.</li> 56<li>When a function is not available in Mesa, or accepts arguments that are not available in OpenGL, it provides its own implementation.</li> 57</ul> 58 59<p>Other than the last case, OpenGL ES uses <code>APIspec.xml</code> to generate functions to check and/or converts the arguments.</p> 60 61</body> 62</html> 63