glGetFramebufferParameter

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Query a named parameter of a framebuffer object.

C Specification[edit]

void glGetFramebufferParameteriv( GLenum target, GLenum pname, GLint * params );
void glGetNamedFramebufferParameteriv( GLuint framebuffer, GLenum pname, GLint * param );


Parameters[edit]

target - Specifies the target to which the framebuffer object is bound for glGetFramebufferParameteriv .
framebuffer - Specifies the name of the framebuffer object for glGetNamedFramebufferParameteriv .
pname - Specifies the parameter of the framebuffer object to query.
params - Returns the value of parameter pname for the framebuffer object.


Description[edit]

 glGetFramebufferParameteriv and glGetNamedFramebufferParameteriv query parameters of a specified framebuffer object.

For glGetFramebufferParameteriv , 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 . Default framebuffers may also be queried if bound to target .

For glGetNamedFramebufferParameteriv , framebuffer is the name of the framebuffer object. If framebuffer is zero, the default draw framebuffer is queried.

Upon successful return, param will contain the value of the framebuffer parameter specified by pname , as described below.

The following parameters can only be queried for framebuffer objects:


GL_FRAMEBUFFER_DEFAULT_WIDTH  -  params returns the value of GL_FRAMEBUFFER_DEFAULT_WIDTH for the framebuffer object.
GL_FRAMEBUFFER_DEFAULT_HEIGHT  -  params returns the value of GL_FRAMEBUFFER_DEFAULT_HEIGHT for the framebuffer object.
GL_FRAMEBUFFER_DEFAULT_LAYERS  -  params returns the value of GL_FRAMEBUFFER_DEFAULT_LAYERS for the framebuffer object.
GL_FRAMEBUFFER_DEFAULT_SAMPLES  -  params returns the value of GL_FRAMEBUFFER_DEFAULT_SAMPLES for the framebuffer object.
GL_FRAMEBUFFER_DEFAULT_FIXED_SAMPLE_LOCATIONS  -  params returns the boolean value of GL_FRAMEBUFFER_DEFAULT_FIXED_SAMPLE_LOCATIONS .

The following parameters can be queried for both default framebuffers and framebuffer objects:


GL_DOUBLEBUFFER  -  param returns a boolean value indicating whether double buffering is supported for the framebuffer object.
GL_IMPLEMENTATION_COLOR_READ_FORMAT  -  param returns a GLenum value indicating the preferred pixel data format for the framebuffer object. See glReadPixels .
GL_IMPLEMENTATION_COLOR_READ_TYPE  -  param returns a GLenum value indicating the implementation's preferred pixel data type for the framebuffer object. See glReadPixels .
GL_SAMPLES  -  param returns an integer value indicating the coverage mask size for the framebuffer object. See glSampleCoverage .
GL_SAMPLE_BUFFERS  -  param returns an integer value indicating the number of sample buffers associated with the framebuffer object. See glSampleCoverage .
GL_STEREO  -  param returns a boolean value indicating whether stereo buffers (left and right) are supported for the framebuffer object.


Notes[edit]

Queries of default framebuffers are supported only if the GL version is 4.5 or higher. Otherwise, an GL_INVALID_OPERATION error is generated.

Queries of the framebuffer-dependent parameters GL_DOUBLEBUFFER , GL_IMPLEMENTATION_COLOR_READ_FORMAT , GL_IMPLEMENTATION_COLOR_READ_TYPE , GL_SAMPLES , GL_SAMPLE_BUFFERS and GL_STEREO are supported only if the GL version is 4.5 or higher.

The framebuffer-dependent state GL_SAMPLE_POSITION cannot be queried with these commands.


Errors[edit]

 GL_INVALID_ENUM is generated by glGetFramebufferParameteriv 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 one of the accepted parameter names.

 GL_INVALID_OPERATION is generated if a default framebuffer is queried, and pname is not one of GL_DOUBLEBUFFER , GL_IMPLEMENTATION_COLOR_READ_FORMAT , GL_IMPLEMENTATION_COLOR_READ_TYPE , GL_SAMPLES , GL_SAMPLE_BUFFERS or GL_STEREO .


Associated Gets[edit]

 glGetFramebufferAttachmentParameter 


Version Support[edit]

 glGetFramebufferParameteriv  4.3+
 glGetNamedFramebufferParameteriv  4.5+

See Also[edit]

 glFramebufferParameteri , glGetFramebufferAttachmentParameter 


Copyright[edit]

Copyright© 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/.