glGetAttribLocation — Returns the location of an attribute variable
GLint glGetAttribLocation( | GLuint | program, |
| const GLchar * | name); |
programSpecifies the program object to be queried.
namePoints to a null terminated string containing the name of the attribute variable whose location is to be queried.
glGetAttribLocation queries the
previously linked program object specified by
program for the attribute variable
specified by name and returns the index
of the generic vertex attribute that is bound to that attribute
variable. If name is a matrix attribute
variable, the index of the first column of the matrix is
returned. If the named attribute variable is not an active
attribute in the specified program object or if
name starts with the reserved prefix
"gl_", a value of -1 is returned.
The association between an attribute variable name and a
generic attribute index can be specified at any time by calling
glBindAttribLocation.
Attribute bindings do not go into effect until
glLinkProgram
is called. After a program object has been linked successfully,
the index values for attribute variables remain fixed until the
next link command occurs. The attribute values can only be
queried after a link if the link was successful.
glGetAttribLocation returns the binding
that actually went into effect the last time
glLinkProgram
was called for the specified program object. Attribute bindings
that have been specified since the last link operation are not
returned by glGetAttribLocation.
GL_INVALID_OPERATION 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_OPERATION is generated if
program has not been successfully
linked.
Copyright © 2003-2005 3Dlabs Inc. Ltd. 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/.