X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=docs%2Fegl.html;h=5b750070ca1ff4e9503240066546a177c1aabf8b;hb=f496d8b86da63f43239457a2f44920401d872bd6;hp=9eba402411d9f1a420173d96f9ada800e831d1f7;hpb=c036d13d7d2cc905226fe53ebd86a18da808963f;p=mesa.git diff --git a/docs/egl.html b/docs/egl.html index 9eba402411d..5b750070ca1 100644 --- a/docs/egl.html +++ b/docs/egl.html @@ -19,35 +19,33 @@ API entry points and helper functions for use by the drivers. Drivers are dynamically loaded by the main library and most of the EGL API calls are directly dispatched to the drivers.

-

The driver in use decides the window system to support. For drivers that -support hardware rendering, there are usually multiple drivers supporting the -same window system. Each one of of them supports a certain range of graphics -cards.

+

The driver in use decides the window system to support.

Build EGL

  1. -

    Run configure with the desired state trackers and and enable -the Gallium driver for your hardware. For example

    +

    Run configure with the desired client APIs and enable +the driver for your hardware. For example

    -  $ ./configure --with-state-trackers=egl,es,vega --enable-gallium-{swrast,intel}
+  $ ./configure --enable-gles1 --enable-gles2 \
+                --with-dri-drivers=... \
+                --with-gallium-drivers=...
    -

    The main library will be enabled by default. The egl state -tracker is needed by a number of EGL drivers. EGL drivers will be covered -later. The es state tracker provides OpenGL ES 1.x -and 2.x and the vega state tracker provides OpenVG -1.x.

    +

    The main library and OpenGL is enabled by default. The first two options +above enables OpenGL ES 1.x and 2.x. The last two +options enables the listed classic and and Gallium drivers respectively.

    +
  2. Build and install Mesa as usual.

In the given example, it will build and install libEGL, -libGLESv1_CM, libGLESv2, libOpenVG, and -one or more EGL drivers.

+libGL, libGLESv1_CM, libGLESv2, and one +or more EGL drivers.

Configure Options

@@ -69,56 +67,57 @@ drivers will be installed to ${libdir}/egl.

-
  • --with-egl-displays +
  • --enable-gallium-egl -

    List the window system(s) to support. It is by default x11, -which supports the X Window System. Its argument is a comma separated string -like, for example, --with-egl-displays=x11,kms. Because an EGL -driver decides which window system to support, this example will enable two -(sets of) EGL drivers. One supports the X window system and the other supports -bare KMS (kernel modesetting).

    +

    Enable the optional egl_gallium driver.

    • -
  • --with-state-trackers +
  • --with-egl-platforms + +

    List the platforms (window systems) to support. Its argument is a comma +seprated string such as --with-egl-platforms=x11,drm. It decides +the platforms a driver may support. The first listed platform is also used by +the main library to decide the native platform: the platform the EGL native +types such as EGLNativeDisplayType or +EGLNativeWindowType defined for.

    -

    The argument is a comma separated string. It is usually used to specify the -rendering APIs, like OpenGL ES or OpenVG, to build. But it should be noted -that a number of EGL drivers depend on the egl state tracker. -They will not be built without the egl state tracker.

    +

    The available platforms are x11, drm, +fbdev, and gdi. The gdi platform can +only be built with SCons. Unless for special needs, the build system should +select the right platforms automatically.

    • -
  • --enable-gallium-swrast +
  • --enable-gles1 and --enable-gles2 -

    This option is not specific to EGL. But if there is no driver for your -hardware, or you are experiencing problems with the hardware driver, you can -enable the swrast DRM driver. It is a dummy driver and EGL will fallback to -software rendering automatically.

    +

    These options enable OpenGL ES support in OpenGL. The result is one big +internal library that supports multiple APIs.

    • - -

    OpenGL

    +
  • --enable-shared-glapi + +

    By default, libGL has its own copy of libglapi. +This options makes libGL use the shared libglapi. This +is required if applications mix OpenGL and OpenGL ES.

    + +
    • -

    The OpenGL state tracker is not built in the above example. It should be -noted that the classic libGL is not a state tracker and cannot be -used with EGL (unless the EGL driver in use is egl_glx). To build -the OpenGL state tracker, one may append glx to ---with-state-trackers and manually build -src/gallium/winsys/xlib/.

    +
  • --enable-openvg + +

    OpenVG must be explicitly enabled by this option.

    + +
    • + +

    Use EGL

    -

    The demos for OpenGL ES and OpenVG can be found in progs/es1/, -progs/es2/ and progs/openvg/. You can use them to -test your build. For example,

    +

    Demos

    -
    -  $ cd progs/es1/xegl
-  $ make
-  $ ./torus
-
    +

    There are demos for the client APIs supported by EGL. They can be found in +mesa/demos repository.

    Environment Variables

    @@ -134,24 +133,38 @@ colon-separated directories where the main library will look for drivers, in addition to the default directory. This variable is ignored for setuid/setgid binaries.

    +

    This variable is usually set to test an uninstalled build. For example, one +may set

    + +
    +  $ export LD_LIBRARY_PATH=$mesa/lib
+  $ export EGL_DRIVERS_PATH=$mesa/lib/egl
+
    + +

    to test a build without installation

    +
  • EGL_DRIVER -

    This variable specifies a full path to an EGL driver and it forces the -specified EGL driver to be loaded. It comes in handy when one wants to test a -specific driver. This variable is ignored for setuid/setgid binaries.

    +

    This variable specifies a full path to or the name of an EGL driver. It +forces the specified EGL driver to be loaded. It comes in handy when one wants +to test a specific driver. This variable is ignored for setuid/setgid +binaries.

    • -
  • EGL_DISPLAY +
  • EGL_PLATFORM -

    When EGL_DRIVER is not set, the main library loads all -EGL drivers that support a certain window system. EGL_DISPLAY can -be used to specify the window system and the valid values are, for example, -x11 or kms. When the variable is not set, the main -library defaults the value to the first window system listed in ---with-egl-displays at configuration time. +

    This variable specifies the native platform. The valid values are the same +as those for --with-egl-platforms. When the variable is not set, +the main library uses the first platform listed in +--with-egl-platforms as the native platform.

    + +

    Extensions like EGL_MESA_drm_display define new functions to +create displays for non-native platforms. These extensions are usually used by +applications that support non-native platforms. Setting this variable is +probably required only for some of the demos found in mesa/demo repository.

    • @@ -173,31 +186,29 @@ variable to true forces the use of software rendering.

    EGL Drivers

    -

    There are two categories of EGL drivers: Gallium and classic.

    + +

    The ABI between the main library and its drivers are not stable. Nor is +there a plan to stabilize it at the moment. Of the EGL drivers, +egl_gallium has its own hardware drivers and client API modules. +They are considered internal to egl_gallium and there is also no +stable ABI between them. These should be kept in mind when packaging for +distribution.

    -

    To use the classic drivers, one must manually set EGL_DRIVER at -runtime.

    +

    Generally, egl_dri2 is preferred over egl_gallium +when the system already has DRI drivers. As egl_gallium is loaded +before egl_dri2 when both are available, egl_gallium +is disabled by default.

    Developers

    @@ -302,16 +307,14 @@ pbuffer surfaces. Therefore, the driver is responsible to guarantee that the client API renders to the specified render buffer for pixmap and pbuffer surfaces.

    -

    TODOs

    +

    EGLDisplay Mutex

    - +The EGLDisplay will be locked before calling any of the dispatch +functions (well, except for GetProcAddress which does not take an +EGLDisplay). This guarantees that the same dispatch function will +not be called with the sample display at the same time. If a driver has access +to an EGLDisplay without going through the EGL APIs, the driver +should as well lock the display before using it.