Unreal 4 Animation System overview

Unreal Engine provides a complete set of animation design system, from basic animation import, to the final character animation control, the process is complete and mature, easy to get started. The following first introduced from the macro-UE4 animation system, and then in-depth introduction of several functional modules.

first, the overall introduction
The following image is translated from the official document, which introduces the context of the animation function as a whole and is simple and straightforward.

At its core is the pawn and character Blueprint , which is the equivalent of a gamer, with a visual skeleton, image, which receives input from the user and lets the character perform some kind of behavior (such as running, jumping). It is worth noting that the character's animation and behavior are separate, even if the character's run animation is not specified, the character can be "run". The animation blueprint that specifies when a character plays what animation.

Roles can still "walk" and "jump" when the character blueprint does not specify an animated blueprint.

The Animation Blueprint is a proprietary blueprint that takes the state of the current character (such as the speed of walking and walking, the state of jumping and jumping, etc.) from the pawn and character blueprints and determines the animation of the character's play based on the data obtained. The event diagram in the animation blueprint is specifically used to get the status of the character, animation diagram is specifically used to determine what animation, animation blueprint decision based on the state machine .

You can specify the animation blueprint used by the current role in the Skeleton Grid component details panel of the character blueprint

The state machine organizes the animations into several states , each of which represents an animation. Status opportunity constantly according to the status of the role to determine what the state of animation, the transition between states is called the transformation rule Transition rules. The use of state machine to determine the animation playback can greatly improve the efficiency.

Typical state machine, state, and transformation rules.

Second, the following complete a basic animation blueprint, control character run.
First, in the animation blueprint of the event diagram to continue to get the role of the current state, and stored in the variable (speed).

Then, in the animated chart, right-click the new state machine and connect to the final animation pose. A state machine is similar to a tick event that will continue to execute, and always output animations at the end of the app's persona.

Double-click the state machine, open it, create a new two state, idle and run. Set the idle to the default state, connect the idle and run states, and specify the conversion conditions for speed>10 and speed <10, respectively. Open the idle and run states and drag into the idle and run animation sequences to connect the final animation posture.

Finally, bind the animation blueprint to the role blueprint. The effect is as follows.

third, other concepts
Animationsequence (animation sequence), one of the most basic animation resources, can be used directly as a state machine status.

Animated notifications (animnotifies or notifications) that give notifications at some point in the animation, play other sounds, effects, and more.

Mixed space Blendspaces, which mixes several animation sequences based on multiple values, reduces the transition between animation sequences, and visualizes the conversion of multiple animation sequences. Official example here

Animmontages animation montage, visual animation organization and management, simplifying the process.

Inverse kinematics (IK), which pushes the animation of other joints through the result of the end, as shown below. Official examples

Blend nodes blend nodes, mixed animations in animated charts through nodes, mainly: Apply Additive (Apply overlay posture), blend (blend), blend poses by bool (mixed by Boolean), blend poses by Int (mixed posture by integer value), layered blend per Bone (based on a layered blend of each bone), and so on. Different mixing nodes mix the input animations in different ways. See here for details.

Animation retargeting to share animations with other models, reducing the cost of animation production. There are two main forms, one is to use the same animation between models with the same skeleton, and the other is to make use of the shared animation by using a rig as a model for different bone structures.

Root motion root motion, which is based on the movement of skeleton root bones animation. as shown below.

The above concepts are more, but the official documentation is very detailed and can be learned slowly.

Unreal 4 Animation System overview