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EDIT TRANSLATE(nged)

NAME

edit translate, edit tra - Translate (move) one or more objects in the database.

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SYNOPSIS

edit [options] geometry translate [-a|-r] [-x|-y|-z] [-k FROM] TO
edit [options] geometry translate [-a|-r] [-x|-y|-z] [-k FROM]
    {x [y [z]]} | {OBJECT}
edit [options] geometry tra X Y Z

where a TO or FROM argument has the form:

{x [y [z]]} | OBJECT_NAME | "."

DESCRIPTION

Used to move one or more instances of primitive or combination objects to a new position. OBJECTs are translated by a vector from FROM to TO.

OFFSET_DIST is always a relative distance from the object’s current position. TO_POS may be either an absolute position (-a) or a relative distance (-r) from FROM. When no -k FROM is given, the relative mode operates directly on the object’s current keypoint (bounding-box center by default).

Any *_OBJECT argument may be set to ., which causes each individual OBJECT to be used in its place (a batch operation if there is more than one OBJECT is supplied on the command line).

The alias tra is a shorthand for translate -r and accepts exactly three coordinate values X Y Z with no flags.

Global options (-S, -f, -F, -i) are described in edit(nged).

OPTIONS

-a

Interpret TO as an absolute position in model space. Required if TO is an object name rather than a coordinate vector. This is the default when -k FROM_OBJECT is given (i.e., the object is moved so that its FROM keypoint coincides with the TO position).

-r

Interpret TO as a relative delta from the current keypoint or FROM position. This is the default when no -k is given.

-x, -y, -z

Restrict the translation to the specified axis only. Only the nominated axis coordinate of TO is applied; the remaining axes stay at their current values. Multiple axis flags may be combined.

-k FROM_COORDS | FROM_OBJECT

Set the reference keypoint (FROM position). FROM accepts:

  • A numeric coordinate triple x y z (1 or 2 values are broadcast to a 3-vector).

  • An object name — its bounding-box center is used.

  • The batch marker . — causes each target object to use its own current keypoint as FROM. Useful for per-object relative moves: translate -k . -a target.s aligns each object individually.

    When `-k` is supplied together with a TO reference, the delta
FROM→TO is applied to the target object (rather than moving it to
an absolute position directly).
-n

Use the natural origin of *_FROM_OBJECT or *_TO_OBJECT rather than the default bounding-box center.

TO

The destination. May be:

  • A coordinate triple x y z (absolute if -a, relative if -r).

  • A single scalar combined with an axis flag (e.g., -a -z 7.8).

  • An object name (moves to that object’s keypoint; use -a for clarity).

  • The batch marker . — each target object uses its own current keypoint as TO. Combined with -k FROM_COORDS, this computes a per-object delta of (own_keypoint − FROM_COORDS), enabling an explosion-from-point effect.

EXAMPLES

Example 1. Translate sph.s to absolute position (15, 0, 0)
mged> **edit sph.s translate -a 15 0 0**
Example 2. Move sph.s by a relative delta of (+5, 0, 0)
mged> **edit sph.s translate -r 5 0 0**

Using the tra alias (always relative):

mged> **edit sph.s tra 5 0 0**
Example 3. Move sph.s from its center to other.s’s center (object-name form)

The -k sph.s -a other.s form computes the delta between the two keypoints and applies it:

mged> **edit sph.s translate -k sph.s -a other.s**

The same delta can also be specified with coordinate positions for -k:

mged> **edit sph.s translate -k 10 0 0 -a other.s**

Or with an explicit coordinate destination:

mged> **edit sph.s translate -k 10 0 0 -a 20 0 0**
Example 4. Align only the Z coordinate of obj to a target elevation of 7.8
mged> **edit obj translate -a -z 7.8**
Example 5. Align several objects to the same Z elevation — using a reference object

Set the Z coordinate of obj1 and obj2 to ref.s’s Z elevation while leaving X and Y unchanged:

mged> **edit obj1 translate -a -z ref.s**
mged> **edit obj2 translate -a -z ref.s**

The -a -z OBJ form extracts the Z component of ref.s’s keypoint (its bounding-box center) and applies it absolutely, keeping the target’s own X and Y. Multiple axis flags can be combined:

mged> **edit obj1 translate -a -x -z ref.s**

This copies both the X and Z of ref.s into obj1, leaving Y unchanged.

Example 6. Move a pair of objects away from the origin (explosion effect)

Each object is moved by a delta equal to its own current position vector, doubling its distance from the origin. Use the . batch marker as TO and 0 0 0 as FROM:

mged> **edit sph.s translate -k 0 0 0 .**
mged> **edit other.s translate -k 0 0 0 .**

For sph.s at (10,0,0): FROM=(0,0,0), TO=own_keypoint=(10,0,0), delta=(10,0,0), result=(20,0,0) — doubled distance from origin.

Equivalently with explicit deltas (when positions are known):

mged> **edit sph.s translate -r 10 0 0**
mged> **edit other.s translate -r 20 0 0**
Example 7. Move a set of objects so that the assembly origin aligns with target.s
mged> **edit assembly translate -k assembly -a target.s**
Example 8. Translate along a path (move a subpart without disturbing the parent)

Using a slash-separated path to name the instance:

mged> **edit assembly/subpart/sph.s translate -r 0 0 10**
Example 9. Use the intermediate buffer: translate tentatively, then revert if unsatisfied

Create a checkpoint (snapshot to revert to):

mged> **edit tor.s checkpoint**

Apply a tentative translation (stays in buffer only):

mged> **edit -i tor.s translate -r 5 0 0**

If satisfied, write to disk:

mged> **edit tor.s translate -r 0 0 0**

If not satisfied, roll back to the checkpoint:

mged> **edit tor.s revert**
Example 10. Operate on the active selection instead of naming objects explicitly

With objects already selected in the viewer:

mged> **edit translate -a 10 0 0**

Force the command-line specifier to override the selection:

mged> **edit -f sph.s translate -a 10 0 0**

SEE ALSO

edit(nged), edit rotate(nged), edit scale(nged), translate(nged), ptranslate(nged)

AUTHOR

BRL-CAD Team

BUG REPORTS

Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org