Std Placement

From FreeCAD Documentation
Revision as of 17:48, 15 September 2020 by Mario52 (talk | contribs) (Marked this version for translation)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
Other languages:
Deutsch • ‎English • ‎français • ‎italiano • ‎română • ‎русский

Std Placement.svg Std Placement

Menu location
Edit → Placement...
Workbenches
All
Default shortcut
None
Introduced in version
-
See also
Std Alignment, Tasks Placement, Placement


Description

The Std Placement command displays the Placement task panel for a selected object.

Std Placement taskpanel.png

The Placement task panel


Usage

  1. Select a single object that has a DataPlacement property in the property editor.
  2. Select the Edit → Placement... option from the menu.
  3. Change one or more of the translation and rotation parameters.
  4. Do one of the following:
    • Press the OK button to apply the changes and close the task panel.
    • Press the Apply button to apply the changes, but keep the task panel open for further changes.
  5. Press Esc or the Cancel button to abort the operation. This will undo any changes that have not been applied.

The dialog can also be launched by clicking on the ellipsis button ... that appears in the property editor when you click on the DataPlacement property.

Notes

Scripting

See also: FreeCAD Scripting Basics.

See the Python scripting tutorial.

A placement is internally defined by a matrix; in many cases it is simpler to represent it by means of two components, a Base point (vector), and a Rotation value. The Rotation itself has different representations; it can be entirely defined by the value of a "quaternion" (xi + yj + zk + w), but it can also be described by a rotation Axis (unit vector) and a rotation Angle (radians).

import FreeCAD as App

doc = App.newDocument()
obj = doc.addObject("Part::Cylinder", "Cylinder")

print(obj.Placement)
# Placement [Pos=(0,0,0), Yaw-Pitch-Roll=(0,0,0)]
print(obj.Placement.Base)
# Vector (0.0, 0.0, 0.0)
print(obj.Placement.Rotation)
# Rotation (0.0, 0.0, 0.0, 1.0)

print(obj.Placement.Rotation.Angle)
# 0.0
print(obj.Placement.Rotation.Axis)
# Vector (0.0, 0.0, 1.0)
print(obj.Placement.Rotation.Q)
# (0.0, 0.0, 0.0, 1.0)

Move the base point of the object, then rotate the object 45 degrees around the X axis.

import math

obj.Placement.Base = App.Vector(5, 3, 1)
obj.Placement.Rotation.Axis = App.Vector(1, 0, 0)
obj.Placement.Rotation.Angle = math.radians(45)

print(obj.Placement)
# Placement [Pos=(5,3,1), Yaw-Pitch-Roll=(0,0,45)]
print(obj.Placement.Rotation.Q)
# (0.3826834323650898, 0.0, 0.0, 0.9238795325112867)
print(obj.Placement.Matrix)
# Matrix ((1,0,0,5),(0,0.707107,-0.707107,3),(0,0.707107,0.707107,1),(0,0,0,1))