Name
glGetAttribLocation — возвращает место в памяти, отведённое под attribute переменную.
C Specification
GLint glGetAttribLocation( |
GLuint |
program, |
| |
const GLchar * |
name); |
Parameters
program
-
Specifies the program object to be queried.
name
-
Points to a null terminated string containing the name of the attribute
variable whose location is to be queried.
Description
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.
Notes
Функция glGetAttribLocation доступна только для OpenGL 2.0 или лучше.
Errors
GL_INVALID_OPERATION будет сгенерировано, если program не сгенерированное OpenGL значение.
GL_INVALID_OPERATION будет сгенерировано, если program не программный объект.
GL_INVALID_OPERATION iбудет сгенерировано, если program has not been successfully linked.
GL_INVALID_OPERATION будет сгенерировано, если glGetAttribLocation вызывается между
glBegin и glEnd.
Copyright
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/.
