Last modified on 15 May 2014, at 06:42

Blender 3D: Noob to Pro/Object Mode

IntroductionEdit

In this module, you will learn some basics about operating in Object mode. This is normally the initial mode that Blender is in when you open a new document; it is the mode where you operate on whole objects, rather than on their parts.

Many of the conventions involving selection and manipulation of objects or parts of objects apply to other modes as well, so this is a good place to start getting familiar with these conventions.

Blender-2.5 mode menu.png
Cube selected in Object mode.

Open a new document, and confirm that you are in Object mode by checking the mode menu.

Select the default cube by clicking on it with  RMB . You will see it framed in an orangey-yellow outline.

Object OriginEdit

When you select an object, you will notice a fat spot appears, normally in the middle of the object, the same orangey-yellow as the rest of the selection.

This is the object’s origin, and it is the reference point for the object’s local coordinate system. Certain kinds of edits to the object can cause this origin to end up at a position well outside the object, in which case operations like transformations applied with reference to the origin may end up not behaving as you expect. But Blender has capabilities to deal with this, which will be explained when you need them.

Multiple SelectionsEdit

You can select more than one object at a time. With the cube still selected, change your view until you can see both it and the default lamp; select the latter by clicking on it with  SHIFT + RMB , so both it and the cube are selected. You will notice that the lamp takes on the orangey-yellow colour, but the cube now has a more reddish highlight.

The active object is the last one selected; other objects can be part of the selection, but the reddish-orange highlight indicates that they are not active. The Properties window shows properties for the active object, not for the entire selection, while operations in the 3D view like moving and deleting objects will affect the entire selection. Some operations (like parenting, which you will learn about later) set up a special relationship between the active object and the rest of the selection, so for these the order of selection of objects becomes important.

You can remove an already-selected object from the selection with  SHIFT + RMB . If you do this, it does not change which object is active (even if it is no longer selected); the little spot indicating the origin of the object’s geometry stays highlighted in the yellow-orange colour, even though the rest of the object loses the selection highlight. Edit by new user to Blender: Version 2.69  SHIFT + RMB  does not necessarily deselect object. It now cycles between selecting as active, deselects or sets as inactive. Toggles through each state in turn. I request confirmation by someone more skilled than I! I can confirm  SHIFT + RMB  in Version 2.69 will deselect an active object, or make an inactive object active.

Pressing  CTRL + I  inverts the selection—it deselects what was previously selected, and selects everything else instead. It does not change the active object.

Selecting Obscured ObjectsEdit

If multiple objects lie under the mouse, you can choose which one to select by clicking  ALT + RMB : this will bring up a menu listing the names of the objects, and you can choose from this menu which one to select.

Alternatively, you can add an object to the current selection, or remove it from the current selection, by clicking  ALT + SHIFT + RMB  and selecting it from the menu.

Selecting Everything and NothingEdit

Pressing  A  does one of two things: if anything is selected, it clears the selection (i.e. selected objects are no longer selected). But if nothing is selected, then it selects everything. You will often see instructions to press  A  either once or twice, to ensure that either nothing is selected, or everything is selected.

Hiding ThingsEdit

When working on a complex model or scene, things are liable to get cluttered, making it hard to see the specific part you’re working on. It is possible to hide objects, so they no longer appear in the 3D view. Just select the object(s) you want to hide, and press  H . This is purely a convenience for working in the 3D view; hidden objects still appear unchanged when you do a render.

Pressing  SHIFT + H  hides everything but the current selection. This is a quick way to banish all the clutter and just narrow the view down to a small number of objects of interest.

Pressing  ALT + H  brings back all hidden objects, and sets the selection to them. If you lose track of what is hidden and what is visible, press this to bring everything back.

Local Versus Global ViewEdit

Local view is another way of selectively hiding parts of the scene: pressing  NUM/  hides everything that is not part of the selection, and automatically zooms in or out as necessary so the selected objects fill the 3D view. Pressing  NUM/  (no substitute key provided for emulated numpad) again restores things as they were before, to the normal global view.

This differs from simple hiding with  H  in that a render done in local view only shows the objects currently visible in that view. In particular, if your lights are excluded from the local view, you are liable to see black blobs in place of your objects.

How do I tell I’m in Local View? Look at the upper-left corner of the 3D view, at the words that describe your current view orientation and perspective settings (e.g. “User Persp”). If the word “(Local)” appears on the end, then you are in local view, otherwise you are in global view.

Border Select (Box Selection)Edit

A quick way to select lots of objects at once is with the Border Select (box selection). Press  B  to activate this, and you will see a pair of dotted crosshairs appear centred at the current mouse position. Drag diagonally with  LMB  to mark out a selection rectangle, then let go, and everything within the rectangle will be added to the selection. Or if you didn’t mean to engage box-selection mode, then as usual pressing  ESC  will get you out of it.

Alternatively, to remove things from the current selection, after pressing  B , drag out the selection rectangle with  MMB , and when you let go, everything in it will be deselected.

Circle Select (Brush Selection)Edit

Another way to select several objects at once is with the Circle Select (brush selection), engaged by pressing  C . In this mode, clicking or dragging on objects with  LMB  adds them to the selection, while  MMB  removes them from the selection. Thus the mouse becomes a brush that you can use to “paint” objects in or out of the selection.

The circle showing the size of the brush can be adjusted with the mouse wheel. This allows you to use a broad brush for selection of lots of objects at once, or a finer one for better control.

Clicking  RMB  or pressing  ESC  terminates Circle Select mode.

The ManipulatorEdit

Manipulator transformation buttons & orientation menu
Manipulator—translations
Manipulator—rotations
Manipulator—scaling

The manipulator appears in the middle of the selection; this is the “click-and-drag” way of applying transformations to objects. You can toggle its visibility with  CTRL + SPACE , or by clicking the little button with the red, green and blue arrows. It can be used to apply translations (changes of position), rotations and scalings (changes of size) to objects, and its appearance changes according to which of these functions are enabled. You can click on any of the transformation buttons that appear when the manipulator is visible to enable just that transformation, or shift-click to enable more than one.

Transform orientations: the “Orientation” menu governs how the axes of the manipulator are aligned, with the default “Global” corresponding to the global coordinate system. Other useful options are “Local”, which corresponds to the local coordinates system of each object, and “View”, which is always aligned to your view.

Click with  RMB  on the camera, so it is the only object selected. Set the manipulator to do only translations, and ensure the orientation is set to “Global”. Drag on any of the coloured lines of the manipulator with  LMB  to move the camera in the corresponding direction.

Now switch the orientation to “Local”. You will see the manipulator lines re-orient themselves. Note that the Z-direction (blue arrow) is now in the direction of the camera view.

With the manipulator orientation still set to Local, add the cube to the selection with  SHIFT + RMB . You will see the manipulator move so it is now in-between the two selected objects. Now if you drag a manipulator arrow with  LMB , each object will move along its own version of that axis.

Switch the orientation to “Global”, and try dragging a manipulator arrow again. This time, both objects will move in the same direction, along the same (global) axis.

Transformation HotkeysEdit

The manipulator is not the only way to apply transformations to objects: this can also be done via keyboard shortcuts.

Hide the manipulator to reduce clutter. Select the cube, and only the cube, again with  RMB . Now press  G . The selection outline around the object turns white, as it did when you were dragging with the manipulator, except this time you haven’t pressed any mouse buttons. Now move the mouse without pressing any buttons, and you will see the object move along with it. Press  LMB  or  ENTER  to terminate the movement and leave the selected object at the new position, or  RMB  or  ESC  to cancel the operation and leave the object at its original location.

Similarly, use  R  to rotate the object, and  S  to scale it.

You can constrain the movement to particular axes by pressing the appropriate keys after the axis key. For example, press  G  to start moving the cube again, and then press  X  and you will see a bright colored line appear parallel to the global X-axis; now when you move the mouse, the cube will only move along that colored line. Similarly  Y  and  Z  constrain movement to the Y- and Z-axes respectively. The colored lines that appear are a brighter reddish, green or blue that correspond to the red, green or blue lines for the X, Y or Z axes, respectively.

Transform orientations: to constrain the transformation to a different set of axes, press the constraint key twice. The coordinate system used depends on the selection in the Transform Orientation menu:

  • Local or Global — the transformation happens in the object’s local coordinate system.
  • View — the transformation is aligned to view coordinates.

For example, with the default “Global” selection from this menu, select the camera with  RMB , press  G  to move it, then press  Z  twice, and you will see the coloured line orient itself along the direction of view of the camera.

These axis constraints also work with scaling, and with rotation (which only happens around the specified axis).

You can also constrain movement and scaling to happen along two axes, but not the third one, by holding down  SHIFT  when typing the axis constraint. For example,  G  followed by  SHIFT + Z  will constrain movement to the global X-Y plane (i.e. any direction except along the Z-axis). To constrain movement to the local X-Y plane, type the contraint twice:  G   SHIFT + Z   SHIFT + Z .

Here’s a summary of what the transformation hotkeys do, with and without constraints:

Key without constraint followed by axis followed by  SHIFT -axis
 G  moves in plane perpendicular to view direction moves along axis moves in plane perpendicular to axis
 R  rotates about view direction rotates about axis
 S  scales uniformly along all axes scales along axis scales uniformly in plane perpendicular to axis

In addition, the hotkey sequence  R   R  enables free rotate, where the object can rotate around all three axes as you move the mouse.

Transforming by NumbersEdit

Blender263TransformPanel.png

Sometimes you need to position things accurately, using calculated numbers, instead of estimating by eye. Blender can do that too; simply type the number after the transformation hotkeys before pressing  ENTER  to confirm the operation. For example,  G   X   1KEY   ENTER  will move the selection by 1 unit in the positive X direction, while  G   X   −KEY   1KEY   ENTER  will move by 1 unit along negative X. Decimal points are also allowed; thus  S   0KEY   .KEY   5KEY   ENTER  will scale the selection by a factor of 0.5, or 50%.

And yet another way is shown at right, in the Transform panel that appears at the top of the Properties shelf (press  N  to toggle its visibility at the right side of the 3D view). Here you can see the existing transformations as numbers, and drag the sliders to change them or click and type to enter new values.

Choosing the Pivot PointEdit

Blender263PivotPointMenu.png

When you do a scaling or rotation operation, you can choose the pivot point, which is the central origin point that remains unaffected by the operation. By default this is the “Median Point”, or centre point of the selection, but the Pivot Point menu lets you choose some other options. For example, select both the cube and the camera, and rotate them ( R ). By default they will rotate around their common centre. Now go to the Pivot Point menu and choose “Individual Origins”; and rotate your two selected objects with  R  again, and you will see each one now rotates about its own centre, rather than the common one.

Another useful pivot option is “3D Cursor”, which means the transformation origin is now the location of the 3D cursor.

Finally, the little button with the three dots and double-headed arrow just to the right of the one that pops up the Pivot Point menu is titled “Manipulate center points”; this means the transformations do not affect the actual objects themselves, only their positions. To see the effect of this, you need to choose a pivot point that is not the object’s origin. Now try a rotation of the object, and you will see that it describes an arc around the pivot point, without changing its orientation; try scaling, and that will change the distance between the object’s origin and the pivot point, without affecting the size of the object itself.

Why can’t I rotate or scale objects? One pitfall you might encounter is that you select an object, try rotating with  R  or scaling with  S , and nothing happens, though moving with  G  still works. It’s quite likely you have the “Manipulate center points” button active when you didn’t mean to. Check if it’s active, and click it to deactivate if so.

Hotkeys — there are keyboard shortcuts for all the above options:

Pivot Option Key
Active Element  ALT + .KEY 
Median Point  CTRL + ,KEY 
Individual Origins  CTRL + .KEY 
3D Cursor  .KEY 
Bounding Box Center  ,KEY 
Toggle Manipulate Center Points  ALT + ,KEY 


Basic Camera TechniqueEdit

The camera view  NUM0  is very useful for making adjustments to your camera while getting continuous feedback on how the render will look. This view shows a framing rectangle covering the area that will appear in the render, surrounded by a passepartout which gives a darkened view of the surrounding part of the scene. You can use the mouse wheel as usual to zoom in and out, adjusting how much of your view is the rendered area and how much is passepartout.

In this view, use  RMB  on the framing rectangle to select the camera, and it will show the usual orange-yellow highlight. The manipulator will not appear even if enabled, so you must use the transformation hotkeys to perform camera transformations.

Use  G  to move the camera around parallel to the view plane. Since the view stays locked to the camera, you will see the actual scene move in the opposite direction to what you might expect.

The camera’s local Z-axis lies along its direction of view. This allows useful operations like  G   Z   Z  to move the camera in or out without affecting the direction in which it’s pointing. Also  R   X   X  to adjust the up-and-down pitch angle,  R   Y   Y  to change the yaw (left-right) angle, and  R   Z   Z  to roll the view around the view direction.

Another useful technique is to position the 3D cursor at a point of interest, set the pivot point to the 3D cursor, then rotate the camera about a global axis, like the global Z-axis ( R   Z ), to adjust the angle of view while keeping the same objects in view, and without altering the distance of the camera from the point of interest.

Scaling the camera object changes its size as shown in the 3D view, but has no effect on the actual render. Regardless of what axis constraints you try to apply, the camera object will always scale uniformly along all axes.

You can also use Fly mode  SHIFT + F  in camera-view mode to fly around the scene, taking the camera with you.

Another choice for moving your camera in Camera View is to bring up the Properties panel ( N ) and, in the View section, tick the box next to Lock Camera to View. Now you will be able to use the  MMB  to "move objects" just as you move things around in other views such as the 3D view. Holding down the  MMB  and dragging will rotate,  Shift + MMB  will allow you to "move the object" around in the view (panning), and the scroll wheel will allow you to "move the object" closer or farther from the camera. You are actually moving the camera with these manipulations and not the object(s) themselves.

Note:

Sizing the Camera: You can scale the camera object with  S  as you can most other objects. However, this has no effect on what is seen with that camera: think of it as a cosmetic thing you can do to make the camera object easier to spot (if it’s too small relative to other objects in the scene), or scale it down to keep it more in proportion when working with smaller objects. However, note a Blender bug: if you scale the camera down from its default size, you will find you can no longer select it with  RMB  on the framing rectangle in camera view.

A better way of changing the displayed size of the camera is to look in the Camera Blender267CameraDataContextButton.png data context in the Properties window, in the Display panel. Here there is a Size field that you can increase or reduce without incurring the above selection bug.

 

Adding/Removing Objects, Undo/Redo, RepeatEdit

Select the cube with  RMB  again. Press either  X  or  DEL  and, after confirming the popup, the cube disappears! It has been deleted from your scene. And unlike mere hiding, it really has disappeared. Press  CTRL + Z  to undo your last operation, and it comes back.

Click with  LMB  to position the 3D cursor somewhere away from the default cube. Press  SHIFT + A  to bring up the Add menu, go to its Mesh submenu, and add another cube to the scene. Again, undo with  CTRL + Z , and you are back to a single cube again.

Now press  CTRL + SHIFT + Z : this will undo the undo, and redo the last operation you undid, bringing back the second cube.

Try adding a third cube; now  CTRL + Z  should undo that and take you back to two cubes, and pressing  CTRL + Z  again should undo the addition of the second cube, taking you back to one. Try  CTRL + SHIFT + Z  at this point to restore the second cube, then  CTRL + SHIFT + Z  again to restore the third one.

Blender remembers up to the last 32 things you did (depending on the limit set in your user preferences) in its undo stack, and you can go back and forth through this with  CTRL + Z  and  CTRL + SHIFT + Z .

Sometimes you want to perform an action repeatedly. To repeat the last action, type  SHIFT + R .

Assigning LayersEdit

You previously learned about showing and hiding layers in the 3D view. To assign the layers for selected objects, press  M . The same keyboard shortcuts apply here as when choosing which layers to display:  1KEY  for only the first layer,  2KEY  for only the second etc,  SHIFT + 1KEY  to include/exclude the first layer and so on.

After assigning an object to a different layer, it disappears! If this happens to you, it’s because the layer(s) you assigned to the object, and the layer(s) you currently have visible in the 3D view, have nothing in common. Simply change the visible layers to include at least one of those you assigned to the object, and it will reappear. For example, if currently only layer 1 is visible, and you assign an object only to layer 2, it will disappear, but reappear when you change the visible layer to layer 2.

Object, Action, SettingsEdit

Bring up the Add menu again ( SHIFT + A ), and this time add a new cylinder mesh to the scene. Look to the left of the 3D view, in the Tool Shelf (toggle its visibility with  T  if it’s not visible); at the bottom you should see a new panel has appeared, titled “Add Cylinder”. Near the top of it is the “Vertices” number, initially defaulting to 32, which gives a fairly round-looking cylinder. Reduce it to 6, and adjust the view as necessary to get a good view of your “cylinder”, and you will see it is now a hexagonal prism. Change the number of vertices to 3, and it becomes a triangular prism.

This is an example of an important user-interface convention that runs right through Blender: first you select the object you want to perform an operation on as appropriate (not applicable here because we are creating a new object), then you perform the specified action with some default settings, and finally you adjust the settings to give the exact result you want. This way, instead of getting a popup before the action is performed, into which you have to put the right settings and hope they will give the right result, you get to interactively adjust the settings and immediately see the results, without having to continually redo the operation and deal with popups.