# GLROTATE

Section: Misc. Reference Manual Pages (3G)
Page Index

## 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

glMatrixMode(3G), glMultMatrix(3G), glPushMatrix(3G), glScale(3G), glTranslate(3G)

NAME
C SPECIFICATION
PARAMETERS
DESCRIPTION
NOTES
ERRORS
ASSOCIATED GETS