NAME
fglRotated, fglRotatef - multiply the current matrix by a
rotation matrix
FORTRAN SPECIFICATION
SUBROUTINE fglRotated( REAL*8 angle,
REAL*8 x,
REAL*8 y,
REAL*8 z )
SUBROUTINE fglRotatef( REAL*4 angle,
REAL*4 x,
REAL*4 y,
REAL*4 z )
PARAMETERS
angle Specifies the angle of rotation, in degrees.
x, y, z
Specify the x, y, and z coordinates of a vector,
respectively.
DESCRIPTION
fglRotate produces a rotation of angle degrees around the
vector (x,y,z). The current matrix (see fglMatrixMode) is
multiplied by a rotation matrix with the product replacing
the current matrix, as if fglMultMatrix were called with the
following matrix as its argument:
( xx(1-c)+c xy(1-c)-zs xz(1-c)+ys 0 )
| |
| yx(1-c)+zs yy(1-c)+c yz(1-c)-xs 0 |
| xz(1-c)-ys yz(1-c)+xs zz(1-c)+c 0 |
| |
( 0 0 0 1 )
Where c = cos(angle), s = sine(angle), and ||( x,y,z )|| = 1
(if not, the GL will normalize this vector).
If the matrix mode is either GL_MODELVIEW or GL_PROJECTION,
all objects drawn after fglRotate is called are rotated.
Use fglPushMatrix and fglPopMatrix to save and restore the
unrotated coordinate system.
NOTES
This rotation follows the right-hand rule, so if the vector
(x,y,z) points toward the user, the rotation will be
counterclockwise.
ERRORS
GL_INVALID_OPERATION is generated if fglRotate is executed
between the execution of fglBegin and the corresponding
execution of fglEnd.
ASSOCIATED GETS
fglGet with argument GL_MATRIX_MODE
fglGet with argument GL_MODELVIEW_MATRIX
fglGet with argument GL_PROJECTION_MATRIX
fglGet with argument GL_TEXTURE_MATRIX
SEE ALSO
fglMatrixMode, fglMultMatrix, fglPushMatrix, fglScale,
fglTranslate