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GLGETVERTEXATTRIB(3G)                            OpenGL 3.3                            GLGETVERTEXATTRIB(3G)



NAME
       glGetVertexAttribdv, glGetVertexAttribfv, glGetVertexAttribiv - Return a generic vertex attribute
       parameter

C SPECIFICATION
       void glGetVertexAttribdv(GLuint index, GLenum pname, GLdouble *params);

       void glGetVertexAttribfv(GLuint index, GLenum pname, GLfloat *params);

       void glGetVertexAttribiv(GLuint index, GLenum pname, GLint *params);

       void glGetVertexAttribIiv(GLuint index, GLenum pname, GLint *params);

       void glGetVertexAttribIuiv(GLuint index, GLenum pname, GLuint *params);

PARAMETERS
       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_DIVISOR, 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_DIVISOR


           params returns a single value that is the frequency divisor used for instanced rendering. See
           glVertexAttribDivisor(). 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).

       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

SEE ALSO
       glBindAttribLocation(), glBindBuffer(), glDisableVertexAttribArray(), glEnableVertexAttribArray(),
       glVertexAttrib(), glVertexAttribDivisor(), glVertexAttribPointer()


COPYRIGHT
       Copyright (C) 2003-2005 3Dlabs Inc. Ltd. Copyright (C) 2010 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/.



OpenGL 3.3                                       03/08/2011                            GLGETVERTEXATTRIB(3G)