glGetFramebufferAttachmentParameteriv, glGetNamedFramebufferAttachmentParameteriv — retrieve information about attachments of a framebuffer object
void glGetFramebufferAttachmentParameteriv(
|
GLenum target, |
GLenum attachment, | |
GLenum pname, | |
GLint *params) ; |
void glGetNamedFramebufferAttachmentParameteriv(
|
GLuint framebuffer, |
GLenum attachment, | |
GLenum pname, | |
GLint *params) ; |
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
.
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_ATTACHMENT
i,
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.
The GL_FRAMEBUFFER_ATTACHMENT_LAYERED
query
is supported only if the GL version is 3.2 or greater.
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
.
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
|
- | - | - | - | - | - | - | - | - | - | - | ✔ |
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. http://opencontent.org/openpub/.