glGetVertexAttrib

Return a generic vertex attribute parameter

Signature

glGetVertexAttribIiv( GLuint ( index ) , GLenum ( pname ) , GLint *( params ) )-> void
glGetVertexAttribIiv( index , pname , params )
glGetVertexAttribIuiv( GLuint ( index ) , GLenum ( pname ) , GLuint *( params ) )-> void
glGetVertexAttribIuiv( index , pname , params )
glGetVertexAttribLdv( GLuint ( index ) , GLenum ( pname ) , GLdouble *( params ) )-> void
glGetVertexAttribLdv( index , pname , params )
glGetVertexAttribdv( GLuint ( index ) , GLenum ( pname ) , GLdouble *( params ) )-> void
glGetVertexAttribdv( index , pname , params )
glGetVertexAttribfv( GLuint ( index ) , GLenum ( pname ) , GLfloat *( params ) )-> void
glGetVertexAttribfv( index , pname , params )
glGetVertexAttribiv( GLuint ( index ) , GLenum ( pname ) , GLint *( params ) )-> void
glGetVertexAttribiv( index , pname , params )

Parameters

VariablesDescription
index
Specifies the generic vertex attribute parameter to be queried.
pname
Specifies the symbolic name of the vertex attribute parameter to be queried. Accepted values are GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING , GL_VERTEX_ATTRIB_ARRAY_ENABLED , GL_VERTEX_ATTRIB_ARRAY_SIZE , GL_VERTEX_ATTRIB_ARRAY_STRIDE , GL_VERTEX_ATTRIB_ARRAY_TYPE , GL_VERTEX_ATTRIB_ARRAY_NORMALIZED , GL_VERTEX_ATTRIB_ARRAY_INTEGER , GL_VERTEX_ATTRIB_ARRAY_LONG , GL_VERTEX_ATTRIB_ARRAY_DIVISOR , GL_VERTEX_ATTRIB_BINDING , GL_VERTEX_ATTRIB_RELATIVE_OFFSET or GL_CURRENT_VERTEX_ATTRIB .
params
Returns the requested data.

Description

glGetVertexAttrib returns in params the value of a generic vertex attribute parameter. The generic vertex attribute to be queried is specified by index , and the parameter to be queried is specified by pname .
The accepted parameter names are as follows:
GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING
params returns a single value, the name of the buffer object currently bound to the binding point corresponding to generic vertex attribute array index . If no buffer object is bound, 0 is returned. The initial value is 0.
GL_VERTEX_ATTRIB_ARRAY_ENABLED
params returns a single value that is non-zero (true) if the vertex attribute array for index is enabled and 0 (false) if it is disabled. The initial value is GL_FALSE .
GL_VERTEX_ATTRIB_ARRAY_SIZE
params returns a single value, the size of the vertex attribute array for index . The size is the number of values for each element of the vertex attribute array, and it will be 1, 2, 3, or 4. The initial value is 4.
GL_VERTEX_ATTRIB_ARRAY_STRIDE
params returns a single value, the array stride for (number of bytes between successive elements in) the vertex attribute array for index . A value of 0 indicates that the array elements are stored sequentially in memory. The initial value is 0.
GL_VERTEX_ATTRIB_ARRAY_TYPE
params returns a single value, a symbolic constant indicating the array type for the vertex attribute array for index . Possible values are GL_BYTE , GL_UNSIGNED_BYTE , GL_SHORT , GL_UNSIGNED_SHORT , GL_INT , GL_UNSIGNED_INT , GL_FLOAT , and GL_DOUBLE . The initial value is GL_FLOAT .
GL_VERTEX_ATTRIB_ARRAY_NORMALIZED
params returns a single value that is non-zero (true) if fixed-point data types for the vertex attribute array indicated by index are normalized when they are converted to floating point, and 0 (false) otherwise. The initial value is GL_FALSE .
GL_VERTEX_ATTRIB_ARRAY_INTEGER
params returns a single value that is non-zero (true) if fixed-point data types for the vertex attribute array indicated by index have integer data types, and 0 (false) otherwise. The initial value is 0 ( GL_FALSE ).
GL_VERTEX_ATTRIB_ARRAY_LONG
param returns a single value that is non-zero (true) if a vertex attribute is stored as an unconverted double, and 0 (false) otherwise. The initial value is 0 ( GL_FALSE ).
GL_VERTEX_ATTRIB_ARRAY_DIVISOR
params returns a single value that is the frequency divisor used for instanced rendering. See glVertexAttribDivisor . The initial value is 0.
GL_VERTEX_ATTRIB_BINDING
params returns a single value, the vertex buffer binding of the vertex attribute array index .
GL_VERTEX_ATTRIB_RELATIVE_OFFSET
params returns a single value that is the byte offset of the first element relative to the start of the vertex buffer binding specified attribute fetches from. The initial value is 0.
GL_CURRENT_VERTEX_ATTRIB
params returns four values that represent the current value for the generic vertex attribute specified by index. Generic vertex attribute 0 is unique in that it has no current state, so an error will be generated if index is 0. The initial value for all other generic vertex attributes is (0,0,0,1).
glGetVertexAttribdv and glGetVertexAttribfv return the current attribute values as four single-precision floating-point values; glGetVertexAttribiv reads them as floating-point values and converts them to four integer values; glGetVertexAttribIiv and glGetVertexAttribIuiv read and return them as signed or unsigned integer values, respectively; glGetVertexAttribLdv reads and returns them as four double-precision floating-point values.
All of the parameters except GL_CURRENT_VERTEX_ATTRIB represent state stored in the currently bound vertex array object.

Notes

If an error is generated, no change is made to the contents of params .

Errors

GL_INVALID_OPERATION is generated if pname is not GL_CURRENT_VERTEX_ATTRIB and there is no currently bound vertex array object.
GL_INVALID_VALUE is generated if index is greater than or equal to GL_MAX_VERTEX_ATTRIBS .
GL_INVALID_ENUM is generated if pname is not an accepted value.
GL_INVALID_OPERATION is generated if index is 0 and pname is GL_CURRENT_VERTEX_ATTRIB .

Associated Gets

glGet with argument GL_MAX_VERTEX_ATTRIBS
glGetVertexAttribPointerv with arguments index and GL_VERTEX_ATTRIB_ARRAY_POINTER

Version Support

glGetVertexAttribIiv
glGetVertexAttribIuiv
glGetVertexAttribLdv
glGetVertexAttribdv
glGetVertexAttribfv
glGetVertexAttribiv

See Also

Copyright

Copyright
2003-2005 3Dlabs Inc. Ltd. 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. .