GLGETFRAMEBUFFERATTA
Section: [FIXME: manual] (3G)
Updated: 01/26/2021
Page Index
NAME
glGetFramebufferAttachmentParameteriv, glGetNamedFramebufferAttachmentParameteriv - retrieve information about attachments of a framebuffer object
C SPECIFICATION
-
void glGetFramebufferAttachmentParameteriv(GLenum target, GLenum attachment, GLenum pname, GLint *params);
-
void glGetNamedFramebufferAttachmentParameteriv(GLuint framebuffer, GLenum attachment, GLenum pname, GLint *params);
PARAMETERS
target
-
- Specifies the target to which the framebuffer object is bound for
glGetFramebufferAttachmentParameteriv.
framebuffer
-
Specifies the name of the framebuffer object for
glGetNamedFramebufferAttachmentParameteriv.
attachment
-
Specifies the attachment of the framebuffer object to query.
pname
-
Specifies the parameter of
attachment
to query.
params
-
Returns the value of parameter
pname
for
attachment.
DESCRIPTION
glGetFramebufferAttachmentParameteriv
and
glGetNamedFramebufferAttachmentParameteriv
return parameters of attachments of a specified framebuffer object.
For
glGetFramebufferAttachmentParameteriv, the framebuffer object is that bound to
target, which must be one of
GL_DRAW_FRAMEBUFFER,
GL_READ_FRAMEBUFFER
or
GL_FRAMEBUFFER.
GL_FRAMEBUFFER
is equivalent to
GL_DRAW_FRAMEBUFFER. Buffers of default framebuffers may also be queried if bound to
target.
For
glGetNamedFramebufferAttachmentParameteriv,
framebuffer
is the name of the framebuffer object. If
framebuffer
is zero, the default draw framebuffer is queried.
If the specified framebuffer is a framebuffer object,
attachment
must be one of
GL_DEPTH_ATTACHMENT,
GL_STENCIL_ATTACHMENT
GL_DEPTH_STENCIL_ATTACHMENT, or
GL_COLOR_ATTACHMENTi, where
i
is between zero and the value of
GL_MAX_COLOR_ATTACHMENTS
minus one.
If the specified framebuffer is a default framebuffer,
target,
attachment
must be one of
GL_FRONT_LEFT,
GL_FRONT_RIGHT,
GL_BACK_LEFT,
GL_BACK_RIGHT,
GL_DEPTH
or
GL_STENCIL, identifying the corresponding buffer.
If
attachment
is
GL_DEPTH_STENCIL_ATTACHMENT, the same object must be bound to both the depth and stencil attachment points of the framebuffer object, and information about that object is returned.
Upon successful return, if
pname
is
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, then
params
will contain one of
GL_NONE,
GL_FRAMEBUFFER_DEFAULT,
GL_TEXTURE, or
GL_RENDERBUFFER, identifying the type of object which contains the attached image. Other values accepted for
pname
depend on the type of object, as described below.
If the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE
is
GL_NONE, then either no framebuffer is bound to
target; or a default framebuffer is queried,
attachment
is
GL_DEPTH
or
GL_STENCIL, and the number of depth or stencil bits, respectively, is zero. In this case querying
pname
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME
will return zero, and all other queries will generate an error.
If the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE
is not
GL_NONE, these queries apply to all other framebuffer types:
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE,
GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE,
GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE,
GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE,
GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE
or
GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE, then
params
will contain the number of bits in the corresponding red, green, blue, alpha, depth, or stencil component of the specified attachment. If the requested component is not present in the attachment, or if no data storage or texture image has been specified for the attachment, then
params
will contain zero.
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE, then
params
will contain the format of components of the specified attachment, one of
GL_FLOAT,
GL_INT,
GL_UNSIGNED_INT,
GL_SIGNED_NORMALIZED, or
GL_UNSIGNED_NORMALIZED
for floating-point, signed integer, unsigned integer, signed normalized fixed-point, or unsigned normalized fixed-point components respectively. Only color buffers may have integer components. If no data storage or texture image has been specified for the attachment, then
params
will contain
GL_NONE. This query cannot be performed for a combined depth+stencil attachment, since it does not have a single format.
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING, then
params
will contain the encoding of components of the specified attachment, one of
GL_LINEAR
or
GL_SRGB
for linear or sRGB-encoded components, respectively. Only color buffer components may be sRGB-encoded; such components are treated as described in the OpenGL Specification. For a default framebuffer, color encoding is determined by the implementation. For framebuffer objects, components are sRGB-encoded if the internal format of a color attachment is one of the color-renderable SRGB formats. If the attachment is not a color attachment, or if no data storage or texture image has been specified for the attachment, then
params
will contain
GL_LINEAR.
If the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE
is
GL_RENDERBUFFER, then
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
params
will contain the name of the renderbuffer object which contains the attached image.
If the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE
is
GL_TEXTURE, then
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, then
params
will contain the name of the texture object which contains the attached image.
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL, then
params
will contain the mipmap level of the texture object which contains the attached image.
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE
and the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME
is the name of a cube map texture object, then
params
will contain the cube map face of the cubemap texture object which contains the attached image. Otherwise
params
will contain zero.
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_LAYERED, then
params
will contain
GL_TRUE
if an entire level of a three-dimensional texture, cube map texture, or one-or two-dimensional array texture is attached. Otherwise,
params
will contain
GL_FALSE.
-
•
If
pname
is
GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER; the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME
is the name of a three-dimensional, or a one- or two-dimensional array texture; and the value of
GL_FRAMEBUFFER_ATTACHMENT_LAYERED
is
GL_FALSE, then
params
will contain the texture layer which contains the attached image. Otherwise
params
will contain zero.
NOTES
The
GL_FRAMEBUFFER_ATTACHMENT_LAYERED
query is supported only if the GL version is 3.2 or greater.
ERRORS
GL_INVALID_ENUM
is generated by
glGetFramebufferAttachmentParameteriv
if
target
is not one of the accepted framebuffer targets.
GL_INVALID_OPERATION
is generated by
glGetNamedFramebufferAttachmentParameteriv
if
framebuffer
is not zero or the name of an existing framebuffer object.
GL_INVALID_ENUM
is generated if
pname
is not valid for the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, as described above.
GL_INVALID_OPERATION
is generated if
attachment
is not one of the accepted framebuffer attachment points, as described above.
GL_INVALID_OPERATION
is generated if the value of
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE
is
GL_NONE
and
pname
is not
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME
or
GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE.
GL_INVALID_OPERATION
is generated if
attachment
is
GL_DEPTH_STENCIL_ATTACHMENT
and different objects are bound to the depth and stencil attachment points of
target.
GL_INVALID_OPERATION
is generated if
attachment
is
GL_DEPTH_STENCIL_ATTACHMENT
and
pname
is
GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE.
VERSION SUPPORT
|
|
OpenGL Version
|
|
Function / Feature Name
|
2.0
|
2.1
|
3.0
|
3.1
|
3.2
|
3.3
|
4.0
|
4.1
|
4.2
|
4.3
|
4.4
|
4.5
|
|
glGetFramebufferAttachmentParameteriv
|
-
|
-
|
✔
|
✔
|
✔
|
✔
|
✔
|
✔
|
✔
|
✔
|
✔
|
✔
|
|
glGetNamedFramebufferAttachmentParameteriv
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
✔
|
SEE ALSO
glGenFramebuffers(),
glBindFramebuffer()
glGetFramebufferParameter()
COPYRIGHT
Copyright
©
2010-2014 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999.
m[blue]http://opencontent.org/openpub/m[].
COPYRIGHT
Copyright © 2010-2014 Khronos Group