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diff --git a/glew/auto/EGL-Registry/sdk/docs/man/html/eglIntro.xhtml b/glew/auto/EGL-Registry/sdk/docs/man/html/eglIntro.xhtml new file mode 100644 index 0000000..b82eade --- /dev/null +++ b/glew/auto/EGL-Registry/sdk/docs/man/html/eglIntro.xhtml @@ -0,0 +1,304 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml"> + <head> + <title xmlns:xlink="http://www.w3.org/1999/xlink">eglIntro - EGL Reference Pages</title> + <link rel="stylesheet" type="text/css" href="khronos-man.css"/> + <meta name="generator" content="DocBook XSL Stylesheets V1.79.1"/> + </head> + <body> + <header/> + <div class="refentry" id="eglIntro"> + <div class="titlepage"/> + <div class="refnamediv"> + <h2>Name</h2> + <p>eglIntro — + introduction to managing client API rendering through the + <abbr class="acronym">EGL</abbr> API. + </p> + </div> + <div class="refsect1" id="overview"> + <h2>Overview</h2> + <p> + The <em class="firstterm">Khronos Native Platform Graphics + Interface</em> (EGL) provides a means for rendering + using a <em class="firstterm">client API</em> such as OpenGL ES + (a 3D renderer for embedded systems), OpenGL (a functional + superset of OpenGL ES for desktop systems), and OpenVG (a 2D + vector graphics renderer) together with a + <em class="firstterm">platform</em>, such as Microsoft Windows or + the X Window System. + </p> + <p> + Depending on its implementation EGL might be more or less + tightly integrated into the platform. Most EGL + functions require an EGL display connection, which can be + obtained by calling + <a class="citerefentry" href="eglGetPlatformDisplay.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetPlatformDisplay</span></span></a> + or + <a class="citerefentry" href="eglGetDisplay.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetDisplay</span></span></a>. + To initialize and + query what EGL version is supported on the display + connection, call + <a class="citerefentry" href="eglInitialize.xhtml"><span class="citerefentry"><span class="refentrytitle">eglInitialize</span></span></a>. + </p> + <p> + The EGL specification does not define the set of platforms that + may be supported by an EGL implementation, nor does it specify + behavior specific to any platform. The set of supported + platforms and their behavior is defined by platform-specific + extensions. To detect if a particular platform is supported, + clients should query the <code class="constant">EGL_EXTENSIONS</code> + string of <code class="constant">EGL_NO_DISPLAY</code> using + <a class="citerefentry" href="eglQueryString.xhtml"><span class="citerefentry"><span class="refentrytitle">eglQueryString</span></span></a>. + </p> + <p> + Platforms supporting EGL make a subset of their + visuals (which may also referred to as pixel formats, frame + buffer configurations, or other similar terms) available for + client API rendering. Windows and pixmaps created with these + visuals may also be rendered into using the platform APIs. + </p> + <p> + An EGL <em class="firstterm">surface</em> extends a native + window or pixmap with additional <em class="firstterm">auxillary + buffers</em>. These buffers include a color buffer, a + depth buffer, a stencil buffer, and an alpha mask buffer. + Some or all of the buffers listed are included in each EGL + frame buffer configuration. + </p> + <p> + EGL supports rendering into three types of surfaces: + windows, pixmaps and pixel buffers (pbuffers). EGL window + and pixmap surfaces are associated with corresponding + resources of the platform. EGL pixel buffers are + EGL-only resources, and do not accept rendering through the + platform APIs. + </p> + <p> + To render using a client API into an EGL surface, you must + determine the appropriate EGL frame buffer configuration, + which supports the rendering features the application + requires. + <a class="citerefentry" href="eglChooseConfig.xhtml"><span class="citerefentry"><span class="refentrytitle">eglChooseConfig</span></span></a> + returns an <span class="type">EGLConfig</span> matching the required + attributes, if any. A complete list of EGL frame buffer + configurations can be obtained by calling + <a class="citerefentry" href="eglGetConfigs.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetConfigs</span></span></a>. + Attributes of a particular EGL frame buffer configuration + can be queried by calling + <a class="citerefentry" href="eglGetConfigAttrib.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetConfigAttrib</span></span></a>. + </p> + <p> + For EGL window and pixmap surfaces, a suitable native window + or pixmap with a matching native visual must be created + first. For a given EGL frame buffer configuration, the + native visual type and ID can be retrieved with a call to + <a class="citerefentry" href="eglGetConfigAttrib.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetConfigAttrib</span></span></a>. + For pixel buffers, no underlying native resource is + required. + </p> + <p> + To create an EGL window surface from a native window, call + <a class="citerefentry" href="eglCreateWindowSurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreateWindowSurface</span></span></a>. + To create an EGL pixmap surface from a native pixmap, call + <a class="citerefentry" href="eglCreatePixmapSurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreatePixmapSurface</span></span></a>. + To create a pixel buffer (pbuffer) surface (which has no + associated native buffer), call + <a class="citerefentry" href="eglCreatePbufferSurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreatePbufferSurface</span></span></a> + To create a pixel buffer (pbuffer) surface whose color + buffer is provided by an OpenVG <span class="type">VGImage</span>, call + <a class="citerefentry" href="eglCreatePbufferFromClientBuffer.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreatePbufferFromClientBuffer</span></span></a>. + Use + <a class="citerefentry" href="eglDestroySurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglDestroySurface</span></span></a> + to release previously allocated resources. + </p> + <p> + An EGL rendering context is required to bind client API + rendering to an EGL surface. An EGL surface and an EGL + rendering context must have compatible EGL frame buffer + configurations. To create an EGL rendering context, call + <a class="citerefentry" href="eglCreateContext.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreateContext</span></span></a>. + The type of client API context created (OpenGL ES, OpenVG, + etc.) can be changed by first calling + <a class="citerefentry" href="eglBindAPI.xhtml"><span class="citerefentry"><span class="refentrytitle">eglBindAPI</span></span></a>. + </p> + <p> + An EGL rendering context may be bound to one or two EGL + surfaces by calling + <a class="citerefentry" href="eglMakeCurrent.xhtml"><span class="citerefentry"><span class="refentrytitle">eglMakeCurrent</span></span></a>. + This context/surface(s) association specifies the + <em class="firstterm">current context</em> and + <em class="firstterm">current surface</em>, and is used by all + client API rendering commands for the bound context until + <a class="citerefentry" href="eglMakeCurrent.xhtml"><span class="citerefentry"><span class="refentrytitle">eglMakeCurrent</span></span></a> + is called with different arguments. + </p> + <p> + Both platform and client API commands may be used to operate + on certain surfaces. However, the two command streams are + not synchronized. Synchronization can be explicitly + specified using by calling + <a class="citerefentry" href="eglWaitClient.xhtml"><span class="citerefentry"><span class="refentrytitle">eglWaitClient</span></span></a>, + <a class="citerefentry" href="eglWaitNative.xhtml"><span class="citerefentry"><span class="refentrytitle">eglWaitNative</span></span></a>, + and possibly by calling other platform APIs. + </p> + </div> + <div class="refsect1" id="examples"> + <h2>Examples</h2> + <p> + Below is a minimal example of creating an RGBA-format window that + allows rendering with OpenGL ES. + The window is cleared to yellow when the program runs. For simplicity, + the program does not check for any errors. + </p> + <pre class="programlisting"> +#include <stdlib.h> +#include <unistd.h> +#include <EGL/egl.h> +#include <GLES/gl.h> +typedef ... NativeWindowType; +extern NativeWindowType createNativeWindow(void); +static EGLint const attribute_list[] = { + EGL_RED_SIZE, 1, + EGL_GREEN_SIZE, 1, + EGL_BLUE_SIZE, 1, + EGL_NONE +}; +int main(int argc, char ** argv) +{ + EGLDisplay display; + EGLConfig config; + EGLContext context; + EGLSurface surface; + NativeWindowType native_window; + EGLint num_config; + + /* get an EGL display connection */ + display = eglGetDisplay(EGL_DEFAULT_DISPLAY); + + /* initialize the EGL display connection */ + eglInitialize(display, NULL, NULL); + + /* get an appropriate EGL frame buffer configuration */ + eglChooseConfig(display, attribute_list, &config, 1, &num_config); + + /* create an EGL rendering context */ + context = eglCreateContext(display, config, EGL_NO_CONTEXT, NULL); + + /* create a native window */ + native_window = createNativeWindow(); + + /* create an EGL window surface */ + surface = eglCreateWindowSurface(display, config, native_window, NULL); + + /* connect the context to the surface */ + eglMakeCurrent(display, surface, surface, context); + + /* clear the color buffer */ + glClearColor(1.0, 1.0, 0.0, 1.0); + glClear(GL_COLOR_BUFFER_BIT); + glFlush(); + + eglSwapBuffers(display, surface); + + sleep(10); + return EXIT_SUCCESS; +} +</pre> + </div> + <div class="refsect1" id="notes"> + <h2>Notes</h2> + <p> + Prior to EGL 1.5, platforms were referred to as the + <em class="firstterm">native window system</em>, and + platform-specific queries and APIs were not available. Only a + single native window system was supported. + </p> + </div> + <div class="refsect1" id="usingeglextensions"> + <h2>Using EGL Extensions</h2> + <p> + All supported EGL extensions will have a corresponding definition in + <code class="filename">egl.h</code> and a token in the extension strings returned + by + <a class="citerefentry" href="eglQueryString.xhtml"><span class="citerefentry"><span class="refentrytitle">eglQueryString</span></span></a>. + </p> + </div> + <div class="refsect1" id="futureeglversions"> + <h2>Future EGL Versions</h2> + <p> + <a class="citerefentry" href="eglInitialize.xhtml"><span class="citerefentry"><span class="refentrytitle">eglInitialize</span></span></a> + and + <a class="citerefentry" href="eglQueryString.xhtml"><span class="citerefentry"><span class="refentrytitle">eglQueryString</span></span></a> + can be used to determine at run-time what version of EGL is available. + To check the EGL version at compile-time, test whether + <code class="constant">EGL_VERSION_<em class="replaceable"><code>x</code></em>_<em class="replaceable"><code>y</code></em></code> + is defined, where <em class="replaceable"><code>x</code></em> and + <em class="replaceable"><code>y</code></em> are the major and minor version + numbers. + </p> + </div> + <div class="refsect1" id="files"> + <h2>Files</h2> + <div class="variablelist"> + <dl class="variablelist"> + <dt> + <span class="term"> + <code class="filename">GLES/egl.h</code> + </span> + </dt> + <dd> + <p> + EGL header file + </p> + </dd> + </dl> + </div> + </div> + <div class="refsect1" id="seealso"> + <h2>See Also</h2> + <p> + + <a class="citerefentry" href="eglBindAPI.xhtml"><span class="citerefentry"><span class="refentrytitle">eglBindAPI</span></span></a>, + <a class="citerefentry" href="eglChooseConfig.xhtml"><span class="citerefentry"><span class="refentrytitle">eglChooseConfig</span></span></a>, + <a class="citerefentry" href="eglCreateContext.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreateContext</span></span></a>, + <a class="citerefentry" href="eglCreatePbufferFromClientBuffer.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreatePbufferFromClientBuffer</span></span></a>, + <a class="citerefentry" href="eglCreatePbufferSurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreatePbufferSurface</span></span></a>, + <a class="citerefentry" href="eglCreatePixmapSurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreatePixmapSurface</span></span></a>, + <a class="citerefentry" href="eglCreateWindowSurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglCreateWindowSurface</span></span></a>, + <a class="citerefentry" href="eglDestroyContext.xhtml"><span class="citerefentry"><span class="refentrytitle">eglDestroyContext</span></span></a>, + <a class="citerefentry" href="eglDestroySurface.xhtml"><span class="citerefentry"><span class="refentrytitle">eglDestroySurface</span></span></a>, + <a class="citerefentry" href="eglGetConfigs.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetConfigs</span></span></a>, + <a class="citerefentry" href="eglGetDisplay.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetDisplay</span></span></a>, + <a class="citerefentry" href="eglGetPlatformDisplay.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetPlatformDisplay</span></span></a>, + <a class="citerefentry" href="eglInitialize.xhtml"><span class="citerefentry"><span class="refentrytitle">eglInitialize</span></span></a>, + <a class="citerefentry" href="eglMakeCurrent.xhtml"><span class="citerefentry"><span class="refentrytitle">eglMakeCurrent</span></span></a>, + <a class="citerefentry" href="eglQueryString.xhtml"><span class="citerefentry"><span class="refentrytitle">eglQueryString</span></span></a>, + <a class="citerefentry" href="eglSwapBuffers.xhtml"><span class="citerefentry"><span class="refentrytitle">eglSwapBuffers</span></span></a>, + <a class="citerefentry" href="eglTerminate.xhtml"><span class="citerefentry"><span class="refentrytitle">eglTerminate</span></span></a>, + <a class="citerefentry" href="eglWaitGL.xhtml"><span class="citerefentry"><span class="refentrytitle">eglWaitGL</span></span></a>, + <a class="citerefentry" href="eglWaitNative.xhtml"><span class="citerefentry"><span class="refentrytitle">eglWaitNative</span></span></a> + </p> + </div> + <p> + </p> + <div class="refsect3" id="copyright"> + <img src="KhronosLogo.jpg"/> + <p> + Copyright © 2003-2014 The Khronos Group Inc. + Permission is hereby granted, free of charge, to any person obtaining a + copy of this software and/or associated documentation files (the + "Materials"), to deal in the Materials without restriction, including + without limitation the rights to use, copy, modify, merge, publish, + distribute, sublicense, and/or sell copies of the Materials, and to + permit persons to whom the Materials are furnished to do so, subject to + the condition that this copyright notice and permission notice shall be included + in all copies or substantial portions of the Materials. + </p> + </div> + <p> +</p> + </div> + <footer/> + </body> +</html> |