2003-2014
The Khronos Group Inc.
eglCreateWindowSurface
3G
eglCreateWindowSurface
create a new EGL window surface
C Specification
EGLSurface eglCreateWindowSurface
EGLDisplay display
EGLConfig config
NativeWindowType native_window
EGLint const * attrib_list
Parameters
display
Specifies the EGL display connection.
config
Specifies the EGL frame buffer configuration that defines the
frame buffer resource available to the surface.
native_window
Specifies the native window.
attrib_list
Specifies window surface attributes.
May be NULL or empty
(first attribute is EGL_NONE).
Description
eglCreateWindowSurface creates an EGL
window surface and returns its handle. If
eglCreateWindowSurface fails to create
a window surface, EGL_NO_SURFACE is
returned.
Surface attributes are specified as a list of
attribute-value pairs, terminated with
EGL_NONE. Accepted attributes
are:
EGL_RENDER_BUFFER
Specifies which buffer should be used for client API
rendering to the window. If its value is
EGL_SINGLE_BUFFER, then client
APIs should render directly into the visible window.
If its value is
EGL_BACK_BUFFER, then client
APIs should render into the back buffer. The default
value of EGL_RENDER_BUFFER is
EGL_BACK_BUFFER.
Client APIs may not be able to respect the requested
rendering buffer. To determine the actual buffer
being rendered to by a context, call
eglQueryContext.
EGL_VG_ALPHA_FORMAT
Specifies how alpha values are interpreted by OpenVG
when rendering to the surface. If its value is
EGL_VG_ALPHA_FORMAT_NONPRE,
then alpha values are not premultipled. If its value
is EGL_VG_ALPHA_FORMAT_PRE,
then alpha values are premultiplied. The default
value of EGL_VG_ALPHA_FORMAT is
EGL_VG_ALPHA_FORMAT_NONPRE.
EGL_VG_COLORSPACE
Specifies the color space used by OpenVG when
rendering to the surface. If its value is
EGL_VG_COLORSPACE_sRGB, then a
non-linear, perceptually uniform color space is
assumed, with a corresponding
VGImageFormat of form
VG_s*. If its value is
EGL_VG_COLORSPACE_LINEAR, then
a linear color space is assumed, with a
corresponding VGImageFormat of form
VG_l*. The default value of
EGL_VG_COLORSPACE is
EGL_VG_COLORSPACE_sRGB.
Any EGL rendering context that was created with respect to
config can be used to render into the
surface. Use
eglMakeCurrent
to attach an EGL rendering context to the surface.
Use
eglQuerySurface
to retrieve the ID of config.
Use
eglDestroySurface
to destroy the surface.
Notes
Attributes EGL_RENDER_BUFFER,
EGL_VG_ALPHA_FORMAT, and
EGL_VG_COLORSPACE, and the
corresponding attribute values, are supported only if the
EGL version is 1.2 or greater.
The EGL_VG_ALPHA_FORMAT and
EGL_VG_COLORSPACE attributes are used
only by OpenVG. EGL itself, and other client APIs such as
OpenGL and OpenGL ES , do not distinguish multiple
colorspace models. Refer to section 11.2 of the OpenVG 1.0
specification for more information. The native window
system's use and interpretation of alpha values is outside
the scope of EGL, although the preferred behavior is for the
window system to ignore the value of
EGL_VG_ALPHA_FORMAT when compositing
window surfaces.
Errors
EGL_NO_SURFACE is returned if creation of
the context fails.
EGL_BAD_DISPLAY is generated if
display is not an EGL display connection.
EGL_NOT_INITIALIZED is generated if
display has not been initialized.
EGL_BAD_CONFIG is generated if
config is not an EGL frame buffer configuration.
EGL_BAD_NATIVE_WINDOW may be generated if
native_window is not a valid native window.
EGL_BAD_ATTRIBUTE is generated if
attrib_list contains an invalid window attribute
or if an attribute value is not recognized or is out of range.
EGL_BAD_ALLOC is generated if there are not
enough resources to allocate the new surface.
EGL_BAD_MATCH is generated if the attributes of
native_window do not correspond to
config or if
config does not support rendering to windows
(the EGL_SURFACE_TYPE attribute does not contain
EGL_WINDOW_BIT).
EGL_BAD_MATCH is generated if
config does not support the specified
OpenVG alpha format attribute (the value of
EGL_VG_ALPHA_FORMAT is
EGL_VG_ALPHA_FORMAT_PRE and the
EGL_VG_ALPHA_FORMAT_PRE_BIT is not set
in the EGL_SURFACE_TYPE attribute of
config) or colorspace attribute (the
value of EGL_VG_COLORSPACE is
EGL_VG_COLORSPACE_LINEAR and the
EGL_VG_COLORSPACE_LINEAR_IT is not set
in the EGL_SURFACE_TYPE attribute of
config).
See Also
eglDestroySurface,
eglChooseConfig,
eglGetConfigs,
eglMakeCurrent,
eglQuerySurface