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); |
programSpecifies the program object to be queried.
uniformCountSpecifies both the number of elements in the array of indices uniformIndices and the
number of parameters written to params upon successful return.
uniformIndicesSpecifies the address of an array of uniformCount integers containing the indices of
uniforms within program whose parameter pname pname.
pnameSpecifies the property of the each uniform in uniformIndices that should be
written into the corresponding element of params.
paramsSpecifies 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,
GL_MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS,
GL_MAX_COMBINED_GEOMETRY_UNIFORM_COMPONENTS,
GL_MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS.
glGetProgram
with argument GL_ACTIVE_UNIFORMS or
GL_ACTIVE_UNIFORM_MAX_LENGTH.
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/.