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GLVERTEXATTRIBPOINTE(3G)                         OpenGL 3.3                         GLVERTEXATTRIBPOINTE(3G)



NAME
       glVertexAttribPointer - define an array of generic vertex attribute data

C SPECIFICATION
       void glVertexAttribPointer(GLuint index, GLint size, GLenum type, GLboolean normalized,
                                  GLsizei stride, const GLvoid * pointer);

       void glVertexAttribIPointer(GLuint index, GLint size, GLenum type, GLsizei stride,
                                   const GLvoid * pointer);

PARAMETERS
       index
           Specifies the index of the generic vertex attribute to be modified.

       size
           Specifies the number of components per generic vertex attribute. Must be 1, 2, 3, 4.
           Additionally, the symbolic constant GL_BGRA is accepted by glVertexAttribPointer. The initial
           value is 4.

       type
           Specifies the data type of each component in the array. The symbolic constants GL_BYTE,
           GL_UNSIGNED_BYTE, GL_SHORT, GL_UNSIGNED_SHORT, GL_INT, and GL_UNSIGNED_INT are accepted by both
           functions. Additionally GL_HALF_FLOAT, GL_FLOAT, GL_DOUBLE, GL_INT_2_10_10_10_REV, and
           GL_UNSIGNED_INT_2_10_10_10_REV are accepted by glVertexAttribPointer. The initial value is
           GL_FLOAT.

       normalized
           For glVertexAttribPointer, specifies whether fixed-point data values should be normalized
           (GL_TRUE) or converted directly as fixed-point values (GL_FALSE) when they are accessed.

       stride
           Specifies the byte offset between consecutive generic vertex attributes. If stride is 0, the
           generic vertex attributes are understood to be tightly packed in the array. The initial value is
           0.

       pointer
           Specifies a offset of the first component of the first generic vertex attribute in the array in
           the data store of the buffer currently bound to the GL_ARRAY_BUFFER target. The initial value is
           0.

DESCRIPTION
       glVertexAttribPointer and glVertexAttribIPointer specify the location and data format of the array of
       generic vertex attributes at index index to use when rendering.  size specifies the number of
       components per attribute and must be 1, 2, 3, 4, or GL_BGRA.  type specifies the data type of each
       component, and stride specifies the byte stride from one attribute to the next, allowing vertices and
       attributes to be packed into a single array or stored in separate arrays.

       For glVertexAttribPointer, if normalized is set to GL_TRUE, it indicates that values stored in an
       integer format are to be mapped to the range [-1,1] (for signed values) or [0,1] (for unsigned
       values) when they are accessed and converted to floating point. Otherwise, values will be converted
       to floats directly without normalization.

       For glVertexAttribIPointer, only the integer types GL_BYTE, GL_UNSIGNED_BYTE, GL_SHORT,
       GL_UNSIGNED_SHORT, GL_INT, GL_UNSIGNED_INT are accepted. Values are always left as integer values.

       If pointer is not NULL, a non-zero named buffer object must be bound to the GL_ARRAY_BUFFER target
       (see glBindBuffer()), otherwise an error is generated.  pointer is treated as a byte offset into the
       buffer object's data store. The buffer object binding (GL_ARRAY_BUFFER_BINDING) is saved as generic
       vertex attribute array state (GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING) for index index.

       When a generic vertex attribute array is specified, size, type, normalized, stride, and pointer are
       saved as vertex array state, in addition to the current vertex array buffer object binding.

       To enable and disable a generic vertex attribute array, call glEnableVertexAttribArray() and
       glDisableVertexAttribArray() with index. If enabled, the generic vertex attribute array is used when
       glDrawArrays(), glMultiDrawArrays(), glDrawElements(), glMultiDrawElements(), or
       glDrawRangeElements() is called.

NOTES
       Each generic vertex attribute array is initially disabled and isn't accessed when glDrawElements(),
       glDrawRangeElements(), glDrawArrays(), glMultiDrawArrays(), or glMultiDrawElements() is called.


       glVertexAttribIPointer is available only if the GL version is 3.0 or higher.

ERRORS
       GL_INVALID_VALUE is generated if index is greater than or equal to GL_MAX_VERTEX_ATTRIBS.

       GL_INVALID_VALUE is generated if size is not 1, 2, 3, 4 or (for glVertexAttribPointer), GL_BGRA.

       GL_INVALID_ENUM is generated if type is not an accepted value.

       GL_INVALID_VALUE is generated if stride is negative.

       GL_INVALID_OPERATION is generated if size is GL_BGRA and type is not GL_INT_2_10_10_10_REV or
       GL_UNSIGNED_INT_2_10_10_10_REV.

       GL_INVALID_OPERATION is generated if type is GL_INT_2_10_10_10_REV or GL_UNSIGNED_INT_2_10_10_10_REV
       and size is not 4 or GL_BGRA.

       GL_INVALID_OPERATION is generated by glVertexAttribPointer if size is GL_BGRA and noramlized is
       GL_FALSE.

       GL_INVALID_OPERATION is generated if zero is bound to the GL_ARRAY_BUFFER buffer object binding point
       and the pointer argument is not NULL.

ASSOCIATED GETS
       glGet() with argument GL_MAX_VERTEX_ATTRIBS

       glGetVertexAttrib() with arguments index and GL_VERTEX_ATTRIB_ARRAY_ENABLED

       glGetVertexAttrib() with arguments index and GL_VERTEX_ATTRIB_ARRAY_SIZE

       glGetVertexAttrib() with arguments index and GL_VERTEX_ATTRIB_ARRAY_TYPE

       glGetVertexAttrib() with arguments index and GL_VERTEX_ATTRIB_ARRAY_NORMALIZED

       glGetVertexAttrib() with arguments index and GL_VERTEX_ATTRIB_ARRAY_STRIDE

       glGetVertexAttrib() with arguments index and GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING

       glGet() with argument GL_ARRAY_BUFFER_BINDING

       glGetVertexAttribPointerv() with arguments index and GL_VERTEX_ATTRIB_ARRAY_POINTER

SEE ALSO
       glBindAttribLocation(), glBindBuffer(), glDisableVertexAttribArray(), glDrawArrays(),
       glDrawElements(), glDrawRangeElements(), glEnableVertexAttribArray(), glMultiDrawArrays(),
       glMultiDrawElements(), glVertexAttrib()


COPYRIGHT
       Copyright (C) 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/.



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