GLROTATE

Section: Misc. Reference Manual Pages (3G)
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NAME

glRotated, glRotatef - multiply the current matrix by a rotation matrix

C SPECIFICATION

void glRotated( GLdouble angle,


                  GLdouble x,
                  GLdouble y,
                  GLdouble z )

void glRotatef( GLfloat angle,


                  GLfloat x,
                  GLfloat y,
                  GLfloat z )

delim $$

PARAMETERS

angle: Specifies the angle of rotation, in degrees.
x, y, z: Specify the x, y, and z coordinates of a vector, respectively.

DESCRIPTION

glRotate produces a rotation of angle degrees around the vector $("x", "y", "z")$. The current matrix (see glMatrixMode) is multiplied by a rotation matrix with the product replacing the current matrix, as if glMultMatrix were called with the following matrix as its argument:

left ( ~ down 20 matrix {
ccol {
   "x" sup 2 (1 ^-^ c)~+~ c above
   "y" "x" (1 ^-^ c)~+~ "z" s above
   "x" "z" (1 ^-^ c)~-~"y" s above
   ~0
}
ccol {
   ~~ "x" "y" (1 ^-^ c)~-~"z" s above
   ~~ "y" sup 2 (1 ^-^ c)~+~ c above
   ~~ "y" "z" (1 ^-^ c)~+~ "x" s above
   ~~ ~0
}
ccol {
   ~~ "x" "z" (1 ^-^ c)~+~ "y" s above
   ~~ "y" "z" (1 ^-^ c)~-~ "x" s above
   ~~ "z" sup 2 (1 ^-^ c) ~+~  c above
   ~~ ~0
}
ccol { ~0 above ~0 above ~0 above ~1} } ~~ right )

Where $c ~=~ cos ("angle")$, $s ~=~ sin ("angle")$, 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 glRotate is called are rotated. Use glPushMatrix and glPopMatrix 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 glRotate is executed between the execution of glBegin and the corresponding execution of glEnd.

ASSOCIATED GETS

glGet with argument GL_MATRIX_MODE
glGet with argument GL_COLOR_MATRIX
glGet with argument GL_MODELVIEW_MATRIX
glGet with argument GL_PROJECTION_MATRIX
glGet with argument GL_TEXTURE_MATRIX