_C_ License Applicability. Except to the extent portions of this file are
_C_ made subject to an alternative license as permitted in the SGI Free
_C_ Software License B, Version 1.1 (the "License"), the contents of this
_C_ file are subject only to the provisions of the License. You may not use
_C_ this file except in compliance with the License. You may obtain a copy
_C_ of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
_C_ Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
_C_ 
_C_ http://oss.sgi.com/projects/FreeB
_C_ 
_C_ Note that, as provided in the License, the Software is distributed on an
_C_ "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
_C_ DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
_C_ CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
_C_ PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
_C_ 
_C_ Original Code. The Original Code is: OpenGL Sample Implementation,
_C_ Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
_C_ Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
_C_ Copyright in any portions created by third parties is as indicated
_C_ elsewhere herein. All Rights Reserved.
_C_ 
_C_ Additional Notice Provisions: The application programming interfaces
_C_ established by SGI in conjunction with the Original Code are The
_C_ OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
_C_ April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
_C_ 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
_C_ Window System(R) (Version 1.3), released October 19, 1998. This software
_C_ was created using the OpenGL(R) version 1.2.1 Sample Implementation
_C_ published by SGI, but has not been independently verified as being
_C_ compliant with the OpenGL(R) version 1.2.1 Specification.
_C_
_C_ The first character in this file must be an '_'!
_C_ Anything on a line after _C_ is ignored
_define(_filters,eqn)_C_
_C_      eqn is automatically replaced with neqn for nroff
_header(Rotate,multiply the current matrix by a rotation matrix)
_names(Rotate,[df])
.EQ
delim $$
.EN
.SH PARAMETERS
_phead(_param1)
Specifies the angle of rotation, in degrees.
_phead(_param2 _param3 _param4)
Specify the \f2x\fP, \f2y\fP, and \f2z\fP coordinates of a vector, respectively. 
.SH DESCRIPTION
_cmnd produces a rotation of _param1 degrees around 
the vector $(_eqnparam2, _eqnparam3, _eqnparam4)$.
The current matrix (see _cmnd(MatrixMode)) is multiplied by a rotation 
matrix with the product
replacing the current matrix, as if _cmnd(MultMatrix) were called
with the following matrix as its argument:
.P
.ce
.EQ 
left ( ~ down 20 matrix {
 ccol { 
   _eqnparam2 sup 2 (1 ^-^ c)~+~ c above
   _eqnparam3 _eqnparam2 (1 ^-^ c)~+~ _eqnparam4 s above
   _eqnparam2 _eqnparam4 (1 ^-^ c)~-~_eqnparam3 s above
   ~0 
 } 
 ccol {
   ~~ _eqnparam2 _eqnparam3 (1 ^-^ c)~-~_eqnparam4 s above
   ~~ _eqnparam3 sup 2 (1 ^-^ c)~+~ c above
   ~~ _eqnparam3 _eqnparam4 (1 ^-^ c)~+~ _eqnparam2 s above
   ~~ ~0
 } 
 ccol {
   ~~ _eqnparam2 _eqnparam4 (1 ^-^ c)~+~ _eqnparam3 s above
   ~~ _eqnparam3 _eqnparam4 (1 ^-^ c)~-~ _eqnparam2 s above
   ~~ _eqnparam4 sup 2 (1 ^-^ c) ~+~  c above
   ~~ ~0
 } 
 ccol { ~0 above ~0 above ~0 above ~1}
} ~~ right )
.EN
.P
.sp
Where $c ~=~ cos (_eqnparam1)$, $s ~=~ sin (_eqnparam1)$, and 
$||(~_eqnparam2, _eqnparam3, _eqnparam4~)|| ~=~ 1$ (if not, the GL 
will normalize this vector).
.sp
.sp
.P
If the matrix mode is either _const(MODELVIEW) or _const(PROJECTION),
all objects drawn after _cmnd is called are rotated.
Use _cmnd(PushMatrix) and _cmnd(PopMatrix) to save and restore
the unrotated coordinate system.
.SH NOTES
This rotation follows the right-hand rule, so
if the vector $(_eqnparam2, _eqnparam3, _eqnparam4)$ points toward the
user, the rotation will be counterclockwise.
.SH ERRORS
_const(INVALID_OPERATION) is generated if _cmnd
is executed between the execution of _cmnd(Begin)
and the corresponding execution of _cmnd(End).
.SH ASSOCIATED GETS
_cmnd(Get) with argument _const(MATRIX_MODE)
.br
_cmnd(Get) with argument _const(COLOR_MATRIX)
.br
_cmnd(Get) with argument _const(MODELVIEW_MATRIX)
.br
_cmnd(Get) with argument _const(PROJECTION_MATRIX)
.br
_cmnd(Get) with argument _const(TEXTURE_MATRIX)
.SH SEE ALSO
_cmnd(MatrixMode),
_cmnd(MultMatrix),
_cmnd(PushMatrix),
_cmnd(Scale),
_cmnd(Translate)
