glGetProgram
3G
glGetProgramiv
Returns a parameter from a program object
C Specification
void glGetProgramiv
GLuint program
GLenum pname
GLint *params
Parameters
program
Specifies the program object to be
queried.
pname
Specifies the object parameter. Accepted
symbolic names are
GL_DELETE_STATUS,
GL_LINK_STATUS,
GL_VALIDATE_STATUS,
GL_INFO_LOG_LENGTH,
GL_ATTACHED_SHADERS,
GL_ACTIVE_ATTRIBUTES,
GL_ACTIVE_ATTRIBUTE_MAX_LENGTH,
GL_ACTIVE_UNIFORMS,
GL_ACTIVE_UNIFORM_BLOCKS,
GL_ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH,
GL_ACTIVE_UNIFORM_MAX_LENGTH,
GL_PROGRAM_BINARY_LENGTH,
GL_TRANSFORM_FEEDBACK_BUFFER_MODE,
GL_TRANSFORM_FEEDBACK_VARYINGS,
GL_TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH,
GL_GEOMETRY_VERTICES_OUT,
GL_GEOMETRY_INPUT_TYPE, and
GL_GEOMETRY_OUTPUT_TYPE.
params
Returns the requested object parameter.
Description
glGetProgram
returns in params
the value of a parameter for a specific program object. The following parameters are defined:
GL_DELETE_STATUS
params returns
GL_TRUE if
program is currently flagged
for deletion, and GL_FALSE
otherwise.
GL_LINK_STATUS
params returns
GL_TRUE if the last link
operation on program was
successful, and GL_FALSE
otherwise.
GL_VALIDATE_STATUS
params returns
GL_TRUE or if the last
validation operation on
program was successful, and
GL_FALSE
otherwise.
GL_INFO_LOG_LENGTH
params returns the
number of characters in the information log for
program including the null
termination character (i.e., the size of the
character buffer required to store the information
log). If program has no
information log, a value of 0 is
returned.
GL_ATTACHED_SHADERS
params returns the
number of shader objects attached to
program.
GL_ACTIVE_ATTRIBUTES
params returns the
number of active attribute variables for
program.
GL_ACTIVE_ATTRIBUTE_MAX_LENGTH
params returns the
length of the longest active attribute name for
program, including the null
termination character (i.e., the size of the
character buffer required to store the longest
attribute name). If no active attributes exist, 0 is
returned.
GL_ACTIVE_UNIFORMS
params returns the
number of active uniform variables for
program.
GL_ACTIVE_UNIFORM_MAX_LENGTH
params returns the
length of the longest active uniform variable name
for program, including the
null termination character (i.e., the size of the
character buffer required to store the longest
uniform variable name). If no active uniform
variables exist, 0 is returned.
GL_PROGRAM_BINARY_LENGTH
params returns the
length of the program binary, in bytes that will be returned by
a call to glGetProgramBinary.
When a progam's GL_LINK_STATUS is GL_FALSE,
its program binary length is zero.
GL_TRANSFORM_FEEDBACK_BUFFER_MODE
params returns a symbolic constant
indicating the buffer mode used when transform feedback is active.
This may be GL_SEPARATE_ATTRIBS or
GL_INTERLEAVED_ATTRIBS.
GL_TRANSFORM_FEEDBACK_VARYINGS
params returns the number of varying
variables to capture in transform feedback mode for the program.
GL_TRANSFORM_FEEDBACK_VARYING_MAX_LENGTH
params returns the length of the longest
variable name to be used for transform feedback, including the null-terminator.
GL_GEOMETRY_VERTICES_OUT
params returns the maximum number of vertices
that the geometry shader in program will output.
GL_GEOMETRY_INPUT_TYPE
params returns a symbolic constant indicating
the primitive type accepted as input to the geometry shader contained in
program.
GL_GEOMETRY_OUTPUT_TYPE
params returns a symbolic constant indicating
the primitive type that will be output by the geometry shader contained
in program.
Notes
GL_ACTIVE_UNIFORM_BLOCKS and
GL_ACTIVE_UNIFORM_BLOCK_MAX_NAME_LENGTH
are available only if the GL version 3.1 or greater.
GL_GEOMETRY_VERTICES_OUT, GL_GEOMETRY_INPUT_TYPE
and GL_GEOMETRY_OUTPUT_TYPE are accepted only if the GL
version is 3.2 or greater.
If an error is generated, no change is made to the
contents of params.
Errors
GL_INVALID_VALUE
is generated if program
is not a value generated by OpenGL.
GL_INVALID_OPERATION
is generated if program
does not refer to a program object.
GL_INVALID_OPERATION is generated if
pname is GL_GEOMETRY_VERTICES_OUT,
GL_GEOMETRY_INPUT_TYPE, or GL_GEOMETRY_OUTPUT_TYPE,
and program does not contain a geometry shader.
GL_INVALID_ENUM
is generated if pname
is not an accepted value.
Associated Gets
glGetActiveAttrib
with argument program
glGetActiveUniform
with argument program
glGetAttachedShaders
with argument program
glGetProgramInfoLog
with argument program
glIsProgram
See Also
glAttachShader,
glCreateProgram,
glDeleteProgram,
glGetShader,
glLinkProgram,
glValidateProgram
Copyright
Copyright 2003-2005 3Dlabs Inc. Ltd.
Copyright 2010 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/.