GLGETACTIVEUNIFORMSI(3G) | OpenGL 3.3 | GLGETACTIVEUNIFORMSI(3G) |

glGetActiveUniformsiv - Returns information about several active uniform variables for the specified program object

**void
glGetActiveUniformsiv(GLuint ***program***,
GLsizei ***uniformCount***,
const GLuint ****uniformIndices***,
GLenum ***pname***,
GLint ****params***);**

*program*

Specifies the program object to be queried.

*uniformCount*

Specifies both the number of elements in the array of
indices *uniformIndices* and the number of parameters written to
*params* upon successful return.

*uniformIndices*

Specifies the address of an array of *uniformCount*
integers containing the indices of uniforms within *program* whose
parameter *pname* pname.

*pname*

Specifies the property of the each uniform in
*uniformIndices* that should be written into the corresponding element of
*params*.

*params*

Specifies the address of an array of *uniformCount*
integers which are to receive the value of *pname* for each uniform in
*uniformIndices*.

**glGetActiveUniformsiv** queries the value of the parameter
named *pname* for each of the uniforms within *program* whose
indices are specified in the array of *uniformCount* unsigned integers
*uniformIndices*. Upon success, the value of the parameter for each
uniform is written into the corresponding entry in the array whose address
is given in *params*. If an error is generated, nothing is written into
*params*.

If *pname* is **GL_UNIFORM_TYPE**, then an array
identifying the types of uniforms specified by the corresponding array of
*uniformIndices* is returned. The returned types can be any of the
values from the following table:

Returned Symbolic Contant |
Shader Uniform Type |

GL_FLOAT |
float |

GL_FLOAT_VEC2 |
vec2 |

GL_FLOAT_VEC3 |
vec3 |

GL_FLOAT_VEC4 |
vec4 |

GL_INT |
int |

GL_INT_VEC2 |
ivec2 |

GL_INT_VEC3 |
ivec3 |

GL_INT_VEC4 |
ivec4 |

GL_UNSIGNED_INT |
unsigned int |

GL_UNSIGNED_INT_VEC2 |
uvec2 |

GL_UNSIGNED_INT_VEC3 |
uvec3 |

GL_UNSIGNED_INT_VEC4 |
uvec4 |

GL_BOOL |
bool |

GL_BOOL_VEC2 |
bvec2 |

GL_BOOL_VEC3 |
bvec3 |

GL_BOOL_VEC4 |
bvec4 |

GL_FLOAT_MAT2 |
mat2 |

GL_FLOAT_MAT3 |
mat3 |

GL_FLOAT_MAT4 |
mat4 |

GL_FLOAT_MAT2x3 |
mat2x3 |

GL_FLOAT_MAT2x4 |
mat2x4 |

GL_FLOAT_MAT3x2 |
mat3x2 |

GL_FLOAT_MAT3x4 |
mat3x4 |

GL_FLOAT_MAT4x2 |
mat4x2 |

GL_FLOAT_MAT4x3 |
mat4x3 |

GL_SAMPLER_1D |
sampler1D |

GL_SAMPLER_2D |
sampler2D |

GL_SAMPLER_3D |
sampler3D |

GL_SAMPLER_CUBE |
samplerCube |

GL_SAMPLER_1D_SHADOW |
sampler1DShadow |

GL_SAMPLER_2D_SHADOW |
sampler2DShadow |

GL_SAMPLER_1D_ARRAY |
sampler1DArray |

GL_SAMPLER_2D_ARRAY |
sampler2DArray |

GL_SAMPLER_1D_ARRAY_SHADOW |
sampler1DArrayShadow |

GL_SAMPLER_2D_ARRAY_SHADOW |
sampler2DArrayShadow |

GL_SAMPLER_2D_MULTISAMPLE |
sampler2DMS |

GL_SAMPLER_2D_MULTISAMPLE_ARRAY |
sampler2DMSArray |

GL_SAMPLER_CUBE_SHADOW |
samplerCubeShadow |

GL_SAMPLER_BUFFER |
samplerBuffer |

GL_SAMPLER_2D_RECT |
sampler2DRect |

GL_SAMPLER_2D_RECT_SHADOW |
sampler2DRectShadow |

GL_INT_SAMPLER_1D |
isampler1D |

GL_INT_SAMPLER_2D |
isampler2D |

GL_INT_SAMPLER_3D |
isampler3D |

GL_INT_SAMPLER_CUBE |
isamplerCube |

GL_INT_SAMPLER_1D_ARRAY |
isampler1DArray |

GL_INT_SAMPLER_2D_ARRAY |
isampler2DArray |

GL_INT_SAMPLER_2D_MULTISAMPLE |
isampler2DMS |

GL_INT_SAMPLER_2D_MULTISAMPLE_ARRAY |
isampler2DMSArray |

GL_INT_SAMPLER_BUFFER |
isamplerBuffer |

GL_INT_SAMPLER_2D_RECT |
isampler2DRect |

GL_UNSIGNED_INT_SAMPLER_1D |
usampler1D |

GL_UNSIGNED_INT_SAMPLER_2D |
usampler2D |

GL_UNSIGNED_INT_SAMPLER_3D |
usampler3D |

GL_UNSIGNED_INT_SAMPLER_CUBE |
usamplerCube |

GL_UNSIGNED_INT_SAMPLER_1D_ARRAY |
usampler2DArray |

GL_UNSIGNED_INT_SAMPLER_2D_ARRAY |
usampler2DArray |

GL_UNSIGNED_INT_SAMPLER_2D_MULTISAMPLE |
usampler2DMS |

GL_UNSIGNED_INT_SAMPLER_2D_MULTISAMPLE_ARRAY |
usampler2DMSArray |

GL_UNSIGNED_INT_SAMPLER_BUFFER |
usamplerBuffer |

GL_UNSIGNED_INT_SAMPLER_2D_RECT |
usampler2DRect |

If *pname* is **GL_UNIFORM_SIZE**, then an array
identifying the size of the uniforms specified by the corresponding array of
*uniformIndices* is returned. The sizes returned are in units of the
type returned by a query of **GL_UNIFORM_TYPE**. For active uniforms that
are arrays, the size is the number of active elements in the array; for all
other uniforms, the size is one.

If *pname* is **GL_UNIFORM_NAME_LENGTH**, then an array
identifying the length, including the terminating null character, of the
uniform name strings specified by the corresponding array of
*uniformIndices* is returned.

If *pname* is **GL_UNIFORM_BLOCK_INDEX**, then an array
identifying the the uniform block index of each of the uniforms specified by
the corresponding array of *uniformIndices* is returned. The uniform
block index of a uniform associated with the default uniform block is
-1.

If *pname* is **GL_UNIFORM_OFFSET**, then an array of
uniform buffer offsets is returned. For uniforms in a named uniform block,
the returned value will be its offset, in basic machine units, relative to
the beginning of the uniform block in the buffer object data store. For
uniforms in the default uniform block, -1 will be returned.

If *pname* is **GL_UNIFORM_ARRAY_STRIDE**, then an array
identifying the stride between elements, in basic machine units, of each of
the uniforms specified by the corresponding array of *uniformIndices*
is returned. The stride of a uniform associated with the default uniform
block is -1. Note that this information only makes sense for uniforms that
are arrays. For uniforms that are not arrays, but are declared in a named
uniform block, an array stride of zero is returned.

If *pname* is **GL_UNIFORM_MATRIX_STRIDE**, then an array
identifying the stride between columns of a column-major matrix or rows of a
row-major matrix, in basic machine units, of each of the uniforms specified
by the corresponding array of *uniformIndices* is returned. The matrix
stride of a uniform associated with the default uniform block is -1. Note
that this information only makes sense for uniforms that are matrices. For
uniforms that are not matrices, but are declared in a named uniform block, a
matrix stride of zero is returned.

If *pname* is **GL_UNIFORM_IS_ROW_MAJOR**, then an array
identifying whether each of the uniforms specified by the corresponding
array of *uniformIndices* is a row-major matrix or not is returned. A
value of one indicates a row-major matrix, and a value of zero indicates a
column-major matrix, a matrix in the default uniform block, or a
non-matrix.

**GL_INVALID_VALUE** is generated if *program* is not a
value generated by OpenGL.

**GL_INVALID_OPERATION** is generated if *program* is not
a program object.

**GL_INVALID_VALUE** is generated if *uniformCount* is
greater than or equal to the value of **GL_ACTIVE_UNIFORMS** for
*program*.

**GL_INVALID_ENUM** is generated if *pname* is not an
accepted token.

**glGet**() with argument
**GL_MAX_VERTEX_UNIFORM_COMPONENTS**,
**GL_MAX_GEOMETRY_UNIFORM_COMPONENTS**,
**GL_MAX_FRAGMENT_UNIFORM_COMPONENTS**, or
**GL_MAX_COMBINED_UNIFORM_COMPONENTS**.

**glGetProgram**() with argument **GL_ACTIVE_UNIFORMS** or
**GL_ACTIVE_UNIFORM_MAX_LENGTH**.

**glIsProgram**()

**glGetUniform**(), **glGetActiveUniform**(),
**glGetUniformLocation**(), **glLinkProgram**(), **glUniform**(),
**glUseProgram**()

Copyright © 2011 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/**.

03/08/2011 | OpenGL 3.3 |