HitReactionController

HitReactionController Inspector

HitReactionController is the per-character hub that receives React() calls and routes them to the matching BodyPartReactor. You’ll usually have one controller per rig—placed on the same GameObject that holds the Animator.

Add via: Component ▸ Hit Reactions ▸ Hit Reaction Controller or automatically when you use the Quick-Start prefab helper.

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Inspector Reference

1. Animator Settings

Field	Default	Description
Animator	(auto-assigned)	Reference to the character’s Animator. Left blank? The component grabs GetComponent<Animator>() at runtime.
Reaction Layer	1	Index of the override layer that carries the additive pose. Must match the layer you created in the Animator Controller (weight is driven automatically).

Tip: Keep the layer type set to Override and weight = 1 in the Animator Controller. The controller sets the weight back to 0 when no hit is active.

2. Body Part Reactors

Drag every BodyPartReactor on the character into this list once. The order does not matter—lookup is done by name.

Column	Description
Element [ ]	Reference to a BodyPartReactor.

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How It Works

1. React() is called by a HitReactionTrigger (or your own code). Parameters:

   React(string partName, Vector3 hitDir, Vector3 hitPoint);

2. The controller loops through reactors[]; when part.name matches partName (case-insensitive) it calls part.React(hitDir, hitPoint).

3. Each frame during a hit, the controller copies the reactor’s weight to the configured Animator layer, keeping additive blending in sync.

Because all per-bone math is isolated in the reactor, the controller stays tiny—just a router.

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Public API Cheatsheet

// Send a generic hit to the chest using projectile velocity
controller.React("Chest", bulletDir, contactPoint);

// Manual melee example using sword swing vector
var dir = swordTip.velocity.normalized;
controller.React("Head", dir, hitPos);

Performance: React() is O(n) over the reactors list, but n is usually < 10. Call sites are event-based (collisions) so overhead is negligible.

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Best Practices

• One controller per rig – placing multiples on child props will double-blend the same bones.

• Animator Controller setup – dedicate a fresh layer; do not reuse your IK or upper-body layers.

• Naming convention – keep bone GameObject names unique per rig (e.g., "Chest", "Chest_1"), or you’ll trigger the wrong reactor.

• Pooling bullets? Make sure pooled projectiles reset their HitReactionTrigger state so they don’t forward stale collisions.

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Next Up

Finish the component set with HitReactionTrigger Inspector, or jump ahead to Recipes & Workflows to see this controller in action across projectiles, swords, and explosions.