Name

glRotate — multiply the current matrix by a rotation matrix

C Specification

void glRotatef(GLfloat angle,
 GLfloat x,
 GLfloat y,
 GLfloat z);
 
void glRotatex(GLfixed angle,
 GLfixed x,
 GLfixed y,
 GLfixed 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

glRotate produces a rotation of angle degrees around the vector xyz . 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:

( x2 (1-c) +c xy (1-c) -zs xz (1-c) +ys 0 xy (1-c) +zs y2 (1-c) +c yz (1-c) -xs 0 xz (1-c) -ys yz (1-c) +xs z2 (1-c) +c 0 0 0 0 1 )

Where c=cosangle , s=sinangle , and ||xyz|| =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 xyz points toward the user, the rotation will be counterclockwise.

Associated Gets

glGet with argument GL_MATRIX_MODE

glGet with argument GL_MODELVIEW_MATRIX

glGet with argument GL_PROJECTION_MATRIX

glGet with argument GL_TEXTURE_MATRIX

See Also

glMatrixMode, glMultMatrix, glPushMatrix, glScale, glTranslate

Copyright

Copyright © 2003-2004 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.