Mechanic Animations. Mecanim is Unity's animation state machine system.

Transcription

1 Mechanic Animations Mecanim is Unity's animation state machine system. It essentially allows you to create 'states' that play animations and define transition logic. Create new project Animation demo.

2 Assets Drag and drop provided folders (Animations, Characters) as well as Tile.jpg into Assets.

3 Animations Select animation folder, animation of your choice and observe behaviour in Inspector panel.

4 Character Setup From Assets > Characters select and in Inspector set Rig tab, Animation Type: Humanoid

5 Character Setup In Project panel, Assets right-click create new Animation Controller. Similarly, create new C# script, name ControllerScript. Save scene as Scene_0.

6 Character Setup Add character to the scene (0, 0, 0)

7 Character Setup With the character in the scene selected, use the Inspector to assign the animator controller. Simply drag it from assets into Animator Controller field.

8 Creating Prefab Create prefab by adding a new empty game object (Player Prefab) in Hierarchy. Drag character Beta@Beta into Player Prefab. For the basic follow add Main Camera to Prefab as well (0, 1.4, -2), (13, 0, 0). Also add plane to the scene

9 Creating Prefab Set plane position to (0, 0, 0) and scale to (10, 1, 10). Drag tile from assets into the plane and set tiling to (100, 100) in Inspector, Tile, Main Maps.

10 Creating Prefab Select character (Beta) and copy Animator component (settings icon on the right, copy component). Select prefab and paste component as new. Back to character and remove Animator Controller.

11 Creating Prefab Add Controller Script to prefab (Add Component, New Script, ControllerScript - one we created earlier). Select prefab, in Inspector, Add Component > Physics > Character Controller. Transformation values might need adjustment. Also, make sure that Apply Root Motion is checked.

12 Creating Prefab Character and prefab are positioned at (0, 0, 0). Set Character Controller s parameters as:

13 Creating Prefab Finally, to create prefab, drag Player Prefab from Hierarchy to Project

14 Animations Creating an Idle/Walk with a Blendtree In the Animator window right-click anywhere on the grid and select "Create > From New Blendtree"

15 Animations This creates a new state and assigns it to be the default state. The default state is always in orange and will be the state that your animation starts out in. Double click on the state to view the blend tree.

16 Animations In order to control this blend tree, we'll need a new parameter. In the top-left of the Animator Window select the + button in the Parameters tab and create a new Float parameter and name it VSpeed

17 Animations Back in the Animator, double click IdleWalk state. Set Parameter to VSpeed. Click the plus button and from Assets, Animations folder, drag Idle animation into the Motion field.

18 Animations Repeat the process and drag walking animation into the second Animation field. Blend tree and associated inspector should look like:

19 Scripting In order to control switching from one state to the other we need to write C# script. Up arrow key down will switch from idle to walking state and up arrow key up will switch from walking to idle state. Open ControllerScript.cs from Assets panel or Player Prefab.

20 Scripting using UnityEngine; using System.Collections; public class BehaviourScript : MonoBehaviour { private Animator myanimator; void Start () { myanimator = GetComponent<Animator>(); } } void Update () { myanimator.setfloat ("VSpeed", Input.GetAxis ("Vertical")); }

21 It s alive!

22 Transitions between states based on parameter Left/Right strafe animations Transitions between animations can be based on parameter. In animator/parameters add another parameter - HSpeed

23 Transitions between states based on parameter Animations can be dragged directly from our project window onto the animator grid to create a new state:

24 Transitions between states based on parameter To create the actual transition right-click on IdleWalk state (make transition) and connect it to left_strafe state:

25 Transitions between states based on parameter Each transition has rules for when it is allowed to occur. The default transition is 'exit time'. That means that as soon as the current animation is done playing, it will transition into the next. We don't want to automatically transition, so instead we're going to transition based on our HSpeed parameter.

26 Transitions between states based on parameter Click on the transition arrow and the inspector will show some additional information. Towards the bottom you'll see an area called Conditions. Change the condition from Blend time to "HSpeed".

27 Transitions between states based on parameter For this particular transition we want HSpeed to be less than -0.1 because GetAxis uses -1 as Left, 0 as neutral and 1 as right. Also uncheck Has Exit Time and Fixed Duration. In order to return to IdleWalk state we need a transition from left_strafe to IdleWalk

28 Transitions between states based on parameter For this particular transition we want HSpeed to be less than -0.1 because GetAxis uses -1 as Left, 0 as neutral and 1 as right. Also uncheck Has Exit Time and Fixed Duration. In order to return to IdleWalk state we need a transition from left_strafe to IdleWalk

29 Transitions between states based on parameter As before, add new condition based on HSpeed being greater than -0.1 and uncheck Has Exit Time and Fixed Duration Transitions to/from right_strafe are similar: IdleWalk to right_strafe: HSpeed > 0.1 right_strafe to IdleWalk: HSpeed < 0.1

30 Script In order to with from IdleWalk/left-right strafe we need a single line of code in our existing script: myanimator.setfloat("hspeed", Input.GetAxis("Horizontal"));

31 It s alive!

32 Any State Any animation that transitions from Any State is essentially transitioning from ALL states. We'll create a jump animation that lets the character jump whether idling, walking or strafing.

33 Any State First, drag the jump animation onto the Animator grid to create a new jump state. We also need a new parameter. This time we'll use a boolean called "Jumping".

34 Any State

35 Any State We want to transition from Any State when Jumping is true. Create a transition between Any State and jump and use the Inspector to change the condition from "Blend" to "Jumping" is true. Uncheck Has Exit Time, but leave Fixed duration.

36 Any State We also need to transition out of jumping back to the IdleWalk blendtree. Create a transition from jump to IdleWalk and leave the condition to exit time. This is because we want to exit jump as soon as the jump animation is over.

37 Any State

38 Script The last thing to do is add the jump controls to our script. This is done in a few steps. First, we need to listen for input (spacebar): if(input.getbuttondown ("Jump")){ myanimator.setbool ("Jumping", true); Invoke ("StopJumping", 0.1f); }

39 Script StopJumping() method simply sets boolean variable Jumping to false: void StopJumping(){ myanimator.setbool ("Jumping", false); }

40 It s alive and jumping!

41 Conditions to Input You can combine conditions in your script with conditions in your animator to create animations that will fire only under very specific conditions. For example, we have some turning animations but they are 'in place' turning, so we only want to use it if the character is standing still.

42 Conditions to Input First, let's add the animations to the animator as two new states - left_turn and right_turn and add two new conditions. We'll make these boolean parameters, called TurningLeft and TurningRight.

43 Conditions to Input

44 Conditions to Input Next, let's create our transitions. We want to transition to turn left only if we are currently standing still (so it has to be from IdleWalk) and only if turning left is true. When it's false, we'll go back to IdleWalk. Same for turning right.

45 Conditions to Input

46 IdleWalk -> left_turn Condition: TurningLeft = true Has Exit Time: unchecked Fixed Duration: unchecked

47 left_turn -> IdleWalk Condition: TurningLeft = false Has Exit Time: unchecked Fixed Duration: unchecked

48 IdleWalk -> right_turn Condition: TurningRight = true Has Exit Time: unchecked Fixed Duration: unchecked

49 IdleWalk -> right_turn Condition: TurningRight = false Has Exit Time: unchecked Fixed Duration: unchecked

50 Conditions to Input Back in our script, we now need to listen for some additional input. We are going to manually assign the Input to be the Q and E keys. When those buttons are pressed and released, we'll toggle TurningLeft and TurningRight respectively to be true and false.

51 Script if(input.getkey( q")) { if((input.getaxis ("Vertical") == 0f) && (Input.GetAxis ("Horizontal") == 0)){ myanimator.setbool ("TurningLeft", true); } } else { myanimator.setbool ("TurningLeft", false); } if(input.getkey("e")){ if((input.getaxis ("Vertical") == 0f) && (Input.GetAxis ("Horizontal") == 0)){ myanimator.setbool ("TurningRight", true); } } else { myanimator.setbool ("TurningRight", false); }

52 Procedural Motion Our player is really NOT turning around when we press Q or E keys. These particular turns don't include 'root motion. So far all of our character movement has been handled completely by the animations driving the game object.

53 Procedural Motion There may be times our animation doesn't have root motion or we specifically want to control the motion of the character through code. We're going to add a procedural turn to our character that will let them actually turn while the turn animation is playing AND allow them to turn while walking/running.

54 Script if(input.getkey("q")){ transform.rotate (Vector3.down * Time.deltaTime * 100.0f); if((input.getaxis ("Vertical") == 0f) && (Input.GetAxis ("Horizontal") == 0)){ myanimator.setbool ("TurningLeft", true); } } else { myanimator.setbool ("TurningLeft", false); }

55 Script if(input.getkey("e")){ transform.rotate (Vector3.up * Time.deltaTime * 100.0f); if((input.getaxis ("Vertical") == 0f) && (Input.GetAxis ("Horizontal") == 0)){ myanimator.setbool ("TurningRight", true); } } else { myanimator.setbool ("TurningRight", false); }

56 It s alive!

57 Sub state machines Sometimes we may have completely separate animation sets that we want to have their own animation logic. Sub State Machines let us create a new grid area with it's own logic. We're going to use a sub state machine to add a few actions to our character (Kneel down, kneel up, dance)

58 Sub state machines To create a sub state machine right-click anywhere on the animator grid and select "Create Sub State Machine". In the inspector, give the sub state machine a name ( Actions ). Sub State machines are represented by a hexagonal state.

59 Sub state machines

60 Sub state machines We also want to create a new parameter - CurrentAction of type int each action in the actions state machine.

61 Sub state machines Double click on the Sub State Machine to enter the sub state. Here, we're going to create a new state by dragging our gangnam style dance into the grid.

62 Sub state machines

63 Sub state machines To create a transition to a state inside a Sub State Machine, right-click on the state you want to transition from, select Make Transition and then click on the Sub State Machine. From the list, select the state you want to transition into.

64 Sub state machines

65 Sub state machines In order to transition OUT of the dance state, we have to set CurrentAction to 0. Uncheck Has Exit Time and Fixed Duration.

66 Sub state machines In order to transition TO dance state, go back to Animator Base Layer, right-click IdleWalk, Make Transition, connect to Actions. Here select state gangnam_style_24.

67 Sub state machines

68 Sub state machines In order to transition INTO the dance state, we have to set CurrentAction to 1. Uncheck Has Exit Time and Fixed Duration.

69 Script if(input.getkeydown ("1")) { if(myanimator.getinteger("currentaction") == 0) { myanimator.setinteger("currentaction", 1); } else if (myanimator.getinteger ("CurrentAction") == 1) { myanimator.setinteger ("CurrentAction", 0); } }

70 It s alive and dancing!

71 Combining techniques We're going to combine several of the previous ideas to create a kneeling toggle. This will use a 3 part animation, the idea of toggles, conditional transitions, exit time transitions, and the integer based index of actions.

72 Combining techniques First, let's add all three animations to the Actions Sub State Machine as three new states. These are kneeling_down, kneeling idle and kneeling_stand.

73 Combining techniques

74 Combining techniques We're going to transition from IdleWalk on the base layer into kneeling_down when CurrentAction is equal to 2.

75 Combining techniques Back in Actions, we need the following transitions: kneeling_down to kneeling_idle on Exit Time kneeling_idle to kneeling_stand if CurrentAction is 0 kneeling_stand to IdleWalk on Exit Time

76 Combining techniques

77 Transitions

78 Script if(input.getkeydown ("2")){ if(myanimator.getinteger ("CurrentAction") == 0) { myanimator.setinteger ("CurrentAction", 2); } else if (myanimator.getinteger ("CurrentAction") == 2) { myanimator.setinteger ("CurrentAction", 0); } }

79 It s alive!

80 Animation Layers It is possible to have multiple layers of animation that affect the layers beneath them. We're going to use a layer to create a wave animation that only plays on the upper body and can be played any time, overriding any animation on the base layer.

81 Animation Layers The first thing we'll need is an avatar mask. You can create an avatar mask using "Assets > Create > Avatar Mask Call it UpperBodyMask

82 Animation Layers Select avatar mask and using inspector deselect legs, left arm and hand. Select ground and four IKs.

83 Animation Layers Back in the Animator, create a new Layer - UpperBody. In UpperBody Layer s settings, set mask to UpperBodyMask and blending to Override.

84 Animation Layers The new layer has an empty state machine. Let's create an empty state by right-clicking the grid and selecting "Create State > Empty" and name it Empty. Let's also drag our wave animation into the grid.

85 Animation Layers The reason for having an empty animation is because sometimes we need a way for this layer to not be playing the wave animation.

86 Animation Layers We'll use our actions indexing integer so we want to transition to the wave animation when CurrentAction is 3. The wave isn't looping, so we'll transition out based on exit time. From Empty to wave if CurrentAction is 3 From wave to Empty on Exit Time

87 Animation Layers

88 Transitions

89 Script if(input.getkeydown ("3")){ myanimator.setlayerweight (1, 1f); myanimator.setinteger("currentaction", 3); } if(input.getkeyup ("3")){ myanimator.setinteger ("CurrentAction", 0); }

90 It s alive!

91 Physics Now that we have our character rigged, let s see how it interacts with the environment. Create a new scene, add plane (scale 10, 1, 10 at 0, 0, 0, grass textured tiling 50, 50) Add cube ((0, 0, 5), (45, 0, 0), (3, 3, 3), stone texture tiling 2, 2) Finally, add Player prefab at 0, 0, 0.

92 Physics

93 Physics So, we can climb slope, assuming angle is less than or equal to 45. How about moving things around? Add couple of more cubes (scale 0.25, 1.5, 0.25). Place the second one on top of the first one.

94 Physics

95 Physics We can t move newly added blocks - we need to add rigid bodies to them. No luck. In order to have our player interact with the environment we need to create a Ragdoll.

96 Physics From the hierarchy, unfold character as shown:

97 Physics Now, create new game object, 3D object, Ragdoll and character s bones from hierarchy into appropriate slots:

98 Physics This process turns each part of character s body into a rigid object. By selecting each part from the hierarchy, you can change default parameters in Inspector.

99 Physics If you play now, you should be able to move rigid objects around.

100 Shoot We can interact with the environment directly, but not yet indirectly. In our next example, we ll shoot cannonballs (or flower bouquets if you prefer) at objects. Create new project Shoot. Create several objects and assign rigid bodies to them.

101 Shoot

102 Camera The shooter will be our camera ((0, 3, 8), (0, 180, 0)) In order to orbit as well as tilt our camera, we need a C# script Cannon.cs

103 Cannon.cs using UnityEngine; using System.Collections; public class Cannon : MonoBehaviour { void Start () {} void Update () { float x = Input.GetAxis("Mouse X") * 2; float y = -Input.GetAxis("Mouse Y"); // vertical tilting float yclamped = transform.eulerangles.x + y; transform.rotation = Quaternion.Euler(yClamped, transform.eulerangles.y, transform.eulerangles.z); } } // horizontal orbiting transform.rotatearound(new Vector3(0, 3, 0), Vector3.up, x);

104 Cannonball Select camera, add component C# script and attach Cannon.cs In order to shoot cannonballs, we need a cannonball. Create a sphere scaled to (0.5, 0.5, 0.5), assign rigid body and drag it from Hierarchy to Assets.

105 Cannonball Back to our Cannon.cs, declare GameObject: public GameObject Cannonball; In order to shoot cannonballs, we need a method: void FixedUpdate () { if (Input.GetButtonDown("Fire1")) { GameObject projectile = Instantiate(Cannonball, transform.position, transform.rotation) as GameObject; projectile.getcomponent<rigidbody>(). AddRelativeForce(new Vector3(20, 20, 2000)); } }

106 Shoot

107 Cannonball Observe, in Hierarchy, the number of cloned cannonballs as we shoot: Even if the cannonball falls of the edge, it will continue to exist as long as the game keeps running and its physics will continue to be calculated, eventually slowing things down.

108 Boundary In order to prevent this, we need to create a boundary and destroy cannonball when it collides with it. Create new Game Object, Empty, rename it to Boundary, position at (0, 0, 0). Add Component, physics, Box Collider. Set it as trigger and position it at:

109 Boundary

110 Boundary Now we have to write a script, Boundary.cs, that will destroy any object colliding with the boundary. using UnityEngine; using System.Collections; public class Boundary : MonoBehaviour { void Start () {} void Update () {} } void OnTriggerExit(Collider other) { Destroy(other.gameObject); }

111 Boundary If you only want to destroy cannonballs, modify ontriggerexit method: void OnTriggerExit(Collider other) { if(other.gameobject.name == "Cannonball(Clone)") { Destroy(other.gameObject); } }

112 Shooting at characters First of all, let s import our character with animations from the asset store: content/5330 Or in asset store, Animation > Bipedal > Raw Mobcap Data for Mecanim

113 Shooting at characters

114 Shooting at characters Import asset and drag avatar into the scene.

115 Shooting at characters Recall that we have to turn character into a rag doll in order to interact with objects. Drag appropriate bones into Ragdoll s dialogue.

116 Shooting at characters If you play the game now, observe that ragdoll collapses instantly. It does respond to cannonballs, but we want it to stand initially and only when hit to turn into a ragdoll.

117 Shooting at characters For that, we need an animator. So, in project, create new animator controller. Open controller, and from Assets > Raw Mocap Data > Animations > Idle, drag Idle_Ready into Animator.

118 Shooting at characters If you play it now, Avatar want collapse, cannonballs bounce of it when hit. How to have the character collapse when hit? Before we proceed, in Project panel, create prefab named Ragdoll and drag DefaultAvatar into it.

119 Shooting at characters You can now delete DefaultAvatar from the Hierarchy and add Ragdoll prefab to the scene. Collision can occur between two colliders, one of them being a cannonball. In order to detect collision between cannonball and anything else we need a script.

120 CannonballCollider.cs using UnityEngine; using System.Collections; public class CannonballCollider : MonoBehaviour { void Start () {} void Update () {} } void OnCollisionEnter (Collision col) { Debug.Log ("Cannonball hit something" + col.gameobject.name); }

121 Shooting at characters Script, of course, needs to be attached to a Cannonball prefab. Rather than detecting collision with each and every bone in our ragdoll, we can add the tag. Select Ragdoll and in Inspector create a new tag ragdollbones

122 Shooting at characters Now, to each and every bone that constitutes our Ragdoll, assign this new tag ragdollbones. We need to modify our script as well: void OnCollisionEnter (Collision col) { if(col.gameobject.tag == "ragdollbones") Debug.Log("Ragdoll hit"); }

123 Shooting at characters The last thing required is for the cannonball to send message to ragdoll prefab, in order to collapse. For this, first of all, we need a new script RagdollController.cs

124 RagdollController.cs using UnityEngine; using System.Collections; public class RagdollController : MonoBehaviour { private Animator anim; void Start () { anim = GetComponent<Animator> (); } void Update () {} } void killragdoll () { anim.enabled = false; }

125 Shooting at characters What remains is to send message killragdoll from CannonballController on collision: void OnCollisionEnter (Collision col) { if(col.gameobject.tag == "ragdollbones") { GameObject.Find( Ragdoll"). SendMessage("killRagdoll"); } }

126 Joints Physics joints in Unity are used to connect (join) two rigid bodies. Here, we ll take a look at fixed, hinge and spring joints.

127 Fixed Joint Fixed Joints restricts an object s movement to be dependent upon another object. This is somewhat similar to Parenting but is implemented through physics rather than Transform hierarchy.

128 Fixed Joint Property Connected body Break force Break torque Enable Collision Enable Description Optional reference to the Rigidbody that the joint is dependent upon. If not set, the joint connects to the world. The force that needs to be applied for this joint to break. The torque that needs to be applied for this joint to break. When checked, this enables collisions between bodies connected with a joint. Disabling preprocessing helps to stabilize impossible-to-fulfil configurations.

129 Hinge Joint The Hinge Joint groups together two Rigidbodies, constraining them to move like they are connected by a hinge. It is perfect for doors, but can also be used to model chains, pendulums, etc.

130 Hinge Joint

131 Hinge Joint Property Connected body Anchor Axis Auto Configure Connected Anchor Connected Anchor Description Optional reference to the Rigidbody that the joint is dependent upon. If not set, the joint connects to the world. The position of the axis around which the body swings. The position is defined in local space. The direction of the axis around which the body swings. The direction is defined in local space. If this is enabled, then the Connected Anchor position will be calculated automatically to match the global position of the anchor property. Manual configuration of the connected anchor position.

132 Hinge Joint Property Spring Description Properties of the Spring that are used if Use Spring is enabled. Spring The force the object asserts to move into the position. Demper Target position Use motor The higher this value, the more the object will slow down. Target angle of the spring. The spring pulls towards this angle measured in degrees. The motor makes the object spin around.

133 Hinge Joint Property Motor Description Properties of the Motor that are used if Use Motor is enabled. Target velocity The speed the object tries to attain. Force The force applied in order to attain the speed. Free Spin Use limits If enabled, the motor is never used to brake the spinning, only accelerate it. If enabled, the angle of the hinge will be restricted within the Min & Max values.

134 Hinge Joint Property Limits Description Properties of the Limits that are used if Use Limits is enabled. Min The lowest angle the rotation can go. Max Bounciness Contact Distance The highest angle the rotation can go. How much the object bounces when it hits the minimum or maximum stop limit. Within the contact distance from the limit contacts will persist in order to avoid jitter.

135 Hinge Joint Property Break force Description The force that needs to be applied for this joint to break. Break torque Enable Collision Enable The torque that needs to be applied for this joint to break. When checked, this enables collisions between bodies connected with a joint. Disabling preprocessing helps to stabilize impossible-to-fulfil configurations.

136 Spring Joint The Spring Joint joins two Rigidbodies together but allows the distance between them to change as though they were connected by a spring.

137 Spring Joint

138 Spring Joint Property Connected body Anchor Auto Configure Connected Anchor Connected Anchor Description Optional reference to the Rigidbody that the joint is dependent upon. If not set, the joint connects to the world. The point in the object s local space at which the joint is attached. Should Unity calculate the position of the connected anchor point automatically? The point in the connected object s local space at which the joint is attached. Spring Strength of the spring. Demper Amount that the spring is reduced when active.

139 Spring Joint Property Min distance Max distance Tolerance Break force Break torque Enable Collision Enable Description Lower limit of the distance range over which the spring will not apply any force. Upper limit of the distance range over which the spring will not apply any force. Changes error tolerance. Allows the spring to have a different rest length. The force that needs to be applied for this joint to break. The torque that needs to be applied for this joint to break. Should the two connected objects register collisions with each other? Disabling preprocessing helps to stabilize impossible-to-fulfil configurations.

140 Example We ll continue with our previous project (Shoot). Let s create a wracking ball first it consists of a sphere and 4 scaled capsules (0.15, 0.25, 0.15) appropriately positioned. All of the objects must have RigidBody component.

141 Example Select the sphere, add component HingeJoint and drag the first link from Hierarchy into the Connected Body component.

142 Example Continue this process: connect link1 to link2, link2 to link3 and link3 to link4 using Hinge Joint. In order to have our wracking ball hanging in the air, we need to add Fixed Joint to the last link - no need to connect it to anything.

143 Shoot!

144 Example Similarly, create five spheres and connect them in bottom-up fashion using Spring Joint. The sphere on top should have the Fixed Joint component.

145 Shoot!