From BlenderWiki

Jump to: navigation, search
Blender3D FreeTip.gif
IMPORTANT! Do not update this page!
We have moved the Blender User Manual to a new location. Please do not update this page, as it will be locked soon.

Using Constraints in Animation

Constraints are a way to control an object’s properties (its location/rotation/scale), using either plain static values (like the “limit” ones), or (an)other object(s), called “targets” (like e.g. the “copy” ones).

Even though these constraints might be useful in static projects, their main usage is obviously in animation. There are two different aspects in constraints’ animation:

  • You can control an object’s animation through the targets used by its constraints (this is a form of indirect animation).
  • You can animate constraints’ settings

Controlling Animation with Constraints

This applies only to constraints using target(s). Indeed, these targets can then control the constraint’s owner’s properties, and hence, animating the targets will indirectly animate the owner.

This indirect “constraint” animation can be very simple, like for example with the Copy Location constraint, where the owner object will simply copy the location of its target (with an optional constant offset). But you can also have very complex behaviors, like when using the Action constraint, which is a sort of Animation Driver for actions!

We should also mention the classical Child Of constraint, which creates parent/child relationship. These relationships indeed imply indirect animation (as transforming the parent affects by default all its children). But the Child Of constraint is also very important, as it allows you to parent your objects to bones, and hence use Armatures to animate them!

Back to our simple Copy Location example, you can have two different behaviors of this constraint:

  • When its Offset button is disabled (the default), the location of the owner is “absolutely” controlled by the constraint’s target, which means nothing (except other constraints below in the stack…) will be able to control the owner’s position. Not even the object’s animation curves.
  • However, when the Offset button is enabled, the location of the owner is “relatively” controlled by the constraint’s target. This means that location’s properties of the owner are offset from the location of the target. And these owner’s location properties can be controlled e.g. by its Loc… curves (or actions, or NLA…)!


Let’s use the Copy Location constraint and its Offset button. For example, you can make your owner (let’s call it moon) describe perfect circles centered on the (0.0, 0.0, 0.0) point (using e.g. pydriven LocX/LocY animation curves, see this page), and then make it copy the location of a target (called, I don’t know… earth, for example) – with the Offset button enabled. Congratulation, you just modeled a satellite in a (simplified) orbit around its planet… Just do the same thing with its planet around its star (which you might call sun, what do you think?), and why not, for the star around its galaxy…

Here is a small animation of a “solar” system created using (among a few others) the technique described above:

Note that the this “solar” system is not realistic at all (wrong scale, the “earth” is rotating in the wrong direction around the “sun”, …).

You can download the the .blend file (File:ManAnimationTechsUsingConstraintsExSolarSys.blend) used to create this animation.

Animating Constraints Influence

More “classically”, you can also animate a few properties of each constraint using animation curves.

You only have two animation curves (see also this page):

  • You can animate the Influence of a constraint. For example, in the “solar system” example above, I used it to first stick the camera to the “moon”, then to the “earth”, and finally to nothing, using two Copy Location constraints with Offset set, and their Influence cross-fading together…
  • More anecdotal, you can also, for some constraints using an armature’s bone as target, animate where along this bone (between root and tip) lays the real target point (0.0 means “full-root”, and 1.0, “full-tip”).

Blender3D FreeTip.gif
This is the old manual!
For the current 2.7x manual see

User Manual

World and Ambient Effects


World Background

Ambient Effects

Stars (2.69)

Game Engine


Introduction to the Game Engine
Game Logic Screen Layout


Logic Properties and States
The Logic Editor


Introduction to Sensors
Sensor Editing
Common Options
-Actuator Sensor
-Always Sensor
-Collision Sensor
-Delay Sensor
-Joystick Sensor
-Keyboard Sensor
-Message Sensor
-Mouse Sensor
-Near Sensor
-Property Sensor
-Radar Sensor
-Random Sensor
-Ray Sensor
-Touch Sensor


Controller Editing
-AND Controller
-OR Controller
-NAND Controller
-NOR Controller
-XOR Controller
-XNOR Controller
-Expression Controller
-Python Controller


Actuator Editing
Common Options
-2D Filters Actuator
-Action Actuator
-Camera Actuator
-Constraint Actuator
-Edit Object Actuator
-Game Actuator
-Message Actuator
-Motion Actuator
-Parent Actuator
-Property Actuator
-Random Actuator
-Scene Actuator
-Sound Actuator
-State Actuator
-Steering Actuator
-Visibility Actuator

Game Properties

Property Editing

Game States



Camera Editing
Stereo Camera
Dome Camera




Material Physics
No Collision Object
Static Object
Dynamic Object
Rigid Body Object
Soft Body Object
Vehicle Controller
Sensor Object
Occluder Object

Path Finding

Navigation Mesh Modifier

Game Performance

Framerate and Profile
Level of Detail

Python API

Bullet physics


Standalone Player
Licensing of Blender Game

Android Support

Android Game development