orient x y z w
orient "x y z w"ORIENT(nged)
NAME
orient, orientation - set the view rotation from a quaternion
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SYNOPSIS
DESCRIPTION
The orient command (also available as orientation) sets the current view’s rotation matrix directly from a unit quaternion. The quaternion components are ordered (x, y, z, w) where (x, y, z) is the vector part and w is the scalar part.
The quaternion may be provided in two forms:
-
Four separate arguments:
orient x y z w— each component as a separate number. -
A single quoted string:
orient "x y z w"— all four components space-separated in one argument, decoded bybn_decode_quat.
Internally, the quaternion is converted to a 4×4 rotation matrix using quat_quat2mat and stored in the view’s gv_rotation field. The view is then updated via bv_update.
This command directly sets the absolute view orientation. It does not apply a relative rotation — to rotate the view by an angle about an axis, use ae (azimuth/elevation) instead.
EXAMPLES
Example 1. Set the view to look straight down the -Z axis (top view)
mged> orient 0.707107 0 0 0.707107
Sets the view orientation to a 90° rotation about the X axis (unit quaternion for a top-down view). The w scalar is approximately cos(45°) and the X vector component is sin(45°).
Example 2. Use the orientation alias
mged> orientation 0 0 0 1
Sets the view to the identity quaternion — the default front-facing orientation with no rotation. orient and orientation are equivalent.
Example 3. Set orientation from a quoted quaternion string
mged> orient "0 0 1 0"
Sets the view using a 180° rotation about the Z axis (quaternion (0, 0, 1, 0)).
SEE ALSO
view(nged)
AUTHOR
BRL-CAD Team
BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org