Blender Documentation: Last modified September 01 2003 S68
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# ObjectMode

The geometry of a Blender scene is constructed from one or more Objects, including, but not limited to, the basic objects described in the Section called Basic objects. Each object can be moved, rotated and scaled; these operations are performed in ObjectMode. For more detailed changes to the geometry, you can work on the mesh of an Object in EditMode (see the Section called EditMode).

After adding a basic object via SPACE->Add menu, Blender changes into EditMode by default. You can change to ObjectMode by pressing TAB. The object's wireframe should now appear pink: That means this object is currently selected and active.

## Selecting objects

Select an object by clicking it with the RMB. Multiple objects can be selected by holding down Shift and clicking with the RMB. Generally, the last object to be selected becomes the active object: It appears in a lighter pink, whereas the non-active selected objects appear purple. The definition of the active object is important for various issues, including parenting.

If you click the active object while Shift is pressed, it is deselected. Pressing AKEY selects all objects in the scene (if none are selected previously) or deselects all (if one or more is selected previously).

BKEY activates Border select: This allows you to draw a rectangle by holding down LMB and then selects all objects that lie within or touch this rectangle. Note that Border select adds to the previous selection, so if you want to be sure to select only the contents of the rectangle, deselect all with AKEY first. Holding down Shift while you draw the border inverts the operation: all objects within the rectangle are deselected.

## Moving (translating) objects

Pressing GKEY activates Grab mode for all selected objects. These are now displayed as white wireframes and can be moved by using the mouse (without pressing any mouse button). To confirm the new position, click LMB or press Enter; to cancel Grab mode, click RMB or press ESC. The distance of your movement is displayed in the header of your 3D window.

You can lock movement to an axis of the global coordinate system. To do this, enter Grab mode, move the object roughly along the desired axis, and press MMB. Deactivate locking by pressing MMB again.

An alternative way to enter Grab mode is to draw a straight line while holding down LMB. The location of selected objects can be reset to the default value by pressing Alt-GKEY.

## Rotating objects

To rotate objects, activate Rotate mode by pressing RKEY. As in Grab mode, you can now change the rotation by moving the mouse, confirm with LMB or Enter and cancel with RMB or ESC.

Rotation in 3D space occurs around an axis, and there are various ways to define this axis. Blender defines an axis via its direction and a point that it passes through. By default, the direction of the axis is orthogonal to your screen. If you are viewing the scene precisely from the front, side or top, the rotation axis will be parallel to one of the global coordinate system axes. If you are viewing from an angle, the rotation axis is angled too, which can easily lead to a very odd rotation of your object. In this case, you may want to keep the rotation axis parallel to the coordinate system axes. Toggle this behaviour by pressing MMB during Rotate mode and watch the angle display in the window header.

The point that the rotation axis should pass through can be selected with four buttons in the header of the 3D window (Figure 2).

Figure 2. The rotation point selection buttons

- If the first button is pushed, the axis passes through the center of the selection's bounding box. (If only one object is selected, the point used is the center point of the object, which must not necessarily be in the geometric center: in Figure 2 it is on the middle of the rightmost edge, marked by a purple dot. For more on this point, see the Section called EditMode.)

- If the second button is pushed, the axis passes through the median point of the selection. This difference is actually relevant only in EditMode and the 'Median' point is the barycentrum of all vertices.

- If the third button is pushed, the axis passes through the 3D cursor. The cursor can be placed anywhere you wish before rotating. Using this tool you can easily perform certain translations in the same working step as the rotation.

- If the fourth button is pushed, each selected object receives its own rotation axis; they are all parallel and pass through the center point of each object, respectively. If you select only one object, you will obviously get the same effect as with the first button.

All these details are very theoretical and not necessary if you are getting started; just play around with Blender's tools and you'll get a feeling for it.

An alternative way to enter Rotate mode is to draw a circular line while holding down LMB. The rotation of selected objects can be reset to the default value by pressing Alt-RKEY.

| Discrete changes
| Remember that by holding CTRL pressed during all these operations you attain discrete changes: translations go in integer numbers, rotation by 5° in 5°, scaling by 0.1.

## Scaling/mirroring objects

To change the size of objects, press SKEY. As in grab mode and rotate mode, scale the objects by moving the mouse, confirm with LMB or Enter and cancel with RMB or ESC.

Scaling in 3D space requires a center point. This point is defined with the same buttons as the axis' supporting point for rotation (Figure 2 in the Section called Rotating objects). If you increase the size of the object, all points are moved away from the selected center point; if you decrease it, all points move towards this point.

By default, the selected objects are scaled uniformly in all directions. To change the proportions (make the object longer, broader, etc.), the scaling process can be locked to one of the global coordinate axes, in the same way as when moving objects: Enter scale mode, move the mouse a bit in the direction of the axis you want to scale, and press MMB. To change back to uniform scaling, press MMB again. You will see the scaling factors in the header of the 3D window.

A different application of the scale tool is mirroring objects, which is effectively nothing but a scaling with a negative factor in one direction. To mirror in the direction of the global X or Y axes, press XKEY or YKEY, respectively, during scale mode. If you want a precise mirroring, make sure you don't move the mouse before confirming the scaling with LMB or Enter.

An alternative way to enter scale mode is to draw a V-shaped line while holding down LMB. The scaling of selected objects can be reset to the default value by pressing Alt-SKEY.

## The number dialog

At some point, you may want to display the effect of your object editing in numbers. Or, if you know the location, rotation and scaling values for an object, you may want to enter them directly instead of having to create them with the mouse. To do this, select the object you want to edit and press NKEY. The number dialog (Figure 3) is displayed; Shift-LMB-click a number to enter a value, press OK to confirm the changes or move the mouse outside the window to cancel.

Figure 3. The number dialog

## Other common object editing tools

The following (incomplete) list gives an overview on Blender's tools for editing in ObjectMode.

Duplicate

  Press Shift-DKEY to create an identical copy of the selected objects. The copy is created at the same position, but is automatically in Grab mode.

Linked duplicate

  Press Alt-DKEY to create new instances of the selected objects. These will link to the original objects' meshes: if you modify one of the linked objects in EditMode, all linked copies will be modified too. The duplicate is created at the same position as the original objects, but is automatically in Grab mode.

Join objects

  Press Ctrl-JKEY to join all selected objects to one single mesh. The center point of the resulting object is obtained from the previously active object (generally the last selected).

Select links

  Press Shift-LKEY to select all linked duplicates of the currently selected objects.

Make parent

  Select several objects, with one of them active, and press Ctrl-PKEY to make the active object the parent of all others selected. This has various uses, the simplest being to create groups of objects: When you move the parent, all children will be moved with it. Use Alt-PKEY to unlink the parent/child connection.

Erase

  Press XKEY or Delete to erase the selected objects. Using XKEY is more practical for most people, because it can easily be reached with the left hand on the keyboard.

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