2003-2018
The Khronos Group Inc.
eglCreatePlatformWindowSurface
3G
eglCreatePlatformWindowSurface
create a new EGL on-screen rendering surface
C Specification
EGLSurface eglCreatePlatformWindowSurface
EGLDisplay display
EGLConfig config
void * native_window
EGLAttrib 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 a list of attributes for the window surface.
May be NULL or empty
(first attribute is EGL_NONE).
Description
eglCreatePlatformWindowSurface creates an
on-screen EGL window surface and returns a handle to it. Any EGL
context created with a compatible EGLConfig can be
used to render into this surface.
If eglCreatePlatformWindowSurface fails to
create a window surface, EGL_NO_SURFACE is
returned.
native_window must belong to the same
platform as display, and EGL considers
the returned EGLSurface as belonging to that same
platform. The EGL extension that defines the platform to which
display belongs also defines the
requirements for the native_window
parameter.
Surface attributes are specified as a list of
attribute-value pairs, terminated with
EGL_NONE. Accepted attributes
are:
EGL_GL_COLORSPACE
Specifies the color space used by OpenGL and OpenGL ES
when rendering to the surface. If its value is
EGL_GL_COLORSPACE_SRGB, then a
non-linear, perceptually uniform color space is assumed,
with a corresponding
GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING
value of GL_SRGB. If its value is
EGL_GL_COLORSPACE_LINEAR, then a
linear color space is assumed, with a corresponding
GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING
value of GL_LINEAR. The default
value of EGL_GL_COLORSPACE is
EGL_GL_COLORSPACE_LINEAR.
Note that the EGL_GL_COLORSPACE
attribute is used only by OpenGL and OpenGL ES contexts
supporting sRGB framebuffers. EGL itself does not
distinguish multiple colorspace models. Refer to the
``sRGB Conversion'' sections of the OpenGL 4.6 and
OpenGL ES 3.2 Specifications for more information.
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
Attribute EGL_GL_COLORSPACE is supported
only if the EGL version is 1.5 or greater.
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 and EGL itself. Refer to section 11.2 of the OpenVG
1.0 specification for more information. The platform's use and
interpretation of alpha values is outside the scope of EGL.
However, the preferred behavior is for platforms to ignore the
value of EGL_VG_ALPHA_FORMAT when
compositing window surfaces.
Errors
If display and
native_window do not belong to the same
platform, then undefined behavior occurs.
EGL_NO_SURFACE is returned if creation of
the surface 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 a valid EGL frame buffer
configuration.
EGL_BAD_NATIVE_WINDOW may be generated if
native_window is not a valid native
window for the same platform as display.
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 is
already an EGLSurface associated with
native_window (as a result of a previous
eglCreatePlatformWindowSurface call).
EGL_BAD_ALLOC is generated if the
implementation cannot allocate resources for the new EGL window.
EGL_BAD_MATCH is generated if the pixel
format of native_window does not
correspond to the format, type, and size of the color buffers
required by config.
EGL_BAD_MATCH is generated if the pixel
EGL_BAD_MATCH is generated 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
eglCreateWindowSurface,
eglDestroySurface,
eglChooseConfig,
eglGetConfigs,
eglMakeCurrent,
eglQuerySurface