feat(physics): add linear and angular velocity to components

.changeset/funny-coats-joke.md

@@ -0,0 +1,5 @@
+---
+'@tedengine/ted': minor
+---
+
+Add linear and angular velocity to scene components

packages/ted/src/actor-components/scene-component.ts

@@ -9,6 +9,7 @@ import type {
 } from '../renderer/frame-params';
 import TActorComponent from './actor-component';
 import type {
+  TPhysicsBody,
   TPhysicsBodyOptions,
   TPhysicsBodyType,
 } from '../physics/physics-world';
@@ -147,4 +148,21 @@ export default class TSceneComponent extends TActorComponent {
   public applyTransform() {
     this.actor?.world?.updateTransform(this);
   }
+
+  private _physicsBody: TPhysicsBody | undefined;
+
+  /**
+   * Set physics body for this component, this is automatically called by the physics world.
+   * Changing this will not update the physics world, use the various `set` methods instead.
+   */
+  public updatePhysicsBody(body: TPhysicsBody | undefined) {
+    this._physicsBody = body;
+  }
+  public get angularVelocity(): vec3 | undefined {
+    return this._physicsBody?.angularVelocity;
+  }
+
+  public get linearVelocity(): vec3 | undefined {
+    return this._physicsBody?.linearVelocity;
+  }
 }

packages/ted/src/cameras/fixed-axis-camera-controller.ts

@@ -30,7 +30,6 @@ export default class TFixedAxisCameraController
 
   public bounds?: { min: vec3; max: vec3 };
 
-  private lastPosition?: vec3;
   public leadFactor = 0; // Adjustable lead factor
   public maxLead = 0; // Maximum lead distance
 
@@ -107,13 +106,8 @@ export default class TFixedAxisCameraController
 
     const currentPosition = this.component.getWorldTransform().translation;
 
-    // Calculate velocity locally
-    const velocity = vec3.create();
-    if (this.lastPosition && this.leadFactor > 0) {
-      vec3.subtract(velocity, currentPosition, this.lastPosition);
-      vec3.scale(velocity, velocity, 1 / delta);
-    }
-    this.lastPosition = vec3.clone(currentPosition);
+    const velocity = this.component.linearVelocity ?? [0, 0, 0];
+    vec3.scale(velocity, velocity, 1 / delta);
 
     // Calculate lead position with maximum lead
     const leadPosition = vec3.create();

packages/ted/src/core/world.ts

@@ -313,6 +313,9 @@ export default class TWorld {
             ...obj.rotation,
           );
 
+          // @todo should we just update the linear and angular velocity here?
+          actor.rootComponent.updatePhysicsBody(obj);
+
           break;
         }
       }

packages/ted/src/physics/physics-world.ts

@@ -66,6 +66,8 @@ export interface TPhysicsBody {
   uuid: string;
   translation: [number, number, number];
   rotation: [number, number, number, number];
+  angularVelocity: [number, number, number];
+  linearVelocity: [number, number, number];
 }
 
 export interface TPhysicsCollision {

packages/ted/src/physics/rapier3d-world.ts

@@ -163,6 +163,16 @@ export default class TRapier3DWorld implements TPhysicsWorld {
           obj.body.rotation().z,
           obj.body.rotation().w,
         ],
+        angularVelocity: [
+          obj.body.angvel().x,
+          obj.body.angvel().y,
+          obj.body.angvel().z,
+        ],
+        linearVelocity: [
+          obj.body.linvel().x,
+          obj.body.linvel().y,
+          obj.body.linvel().z,
+        ],
       });
     }