physics2d supports joint2d apply

cocos/physics-2d/box2d-wasm/joints/joint-2d.ts

@@ -62,6 +62,13 @@ export class B2Joint implements IJoint2D {
         PhysicsSystem2D.instance._callAfterStep(this, this._init);
     }
 
+    apply (): void {
+        PhysicsSystem2D.instance._callAfterStep(this, this.destroy);
+        if (this.comp!.enabledInHierarchy) {
+            PhysicsSystem2D.instance._callAfterStep(this, this._init);
+        }
+    }
+
     _init (): void {
         if (this._inited) return;
 

cocos/physics-2d/box2d/joints/joint-2d.ts

@@ -62,6 +62,13 @@ export class b2Joint implements IJoint2D {
         PhysicsSystem2D.instance._callAfterStep(this, this._init);
     }
 
+    apply (): void {
+        PhysicsSystem2D.instance._callAfterStep(this, this._destroy);
+        if (this.comp!.enabledInHierarchy) {
+            PhysicsSystem2D.instance._callAfterStep(this, this._init);
+        }
+    }
+
     _init (): void {
         if (this._inited) return;
 

cocos/physics-2d/framework/components/joints/joint-2d.ts

@@ -81,7 +81,7 @@ export class Joint2D extends Component {
      * @zh
      * 关节所绑定的刚体组件。
      */
-    _body: RigidBody2D | null = null
+    _body: RigidBody2D | null = null;
     get body (): RigidBody2D | null {
         return this._body;
     }
@@ -132,4 +132,16 @@ export class Joint2D extends Component {
             this._joint.onDestroy();
         }
     }
+
+    /**
+     * @en
+     * If the physics engine is box2d, need to call this function to apply current changes to joint, this will regenerate inner box2d joint.
+     * @zh
+     * 如果物理引擎是 box2d, 需要调用此函数来应用当前 joint 中的修改。
+     */
+    apply (): void {
+        if (this._joint && this._joint.apply) {
+            this._joint.apply();
+        }
+    }
 }

cocos/physics-2d/framework/physics-selector.ts

@@ -297,6 +297,7 @@ const ENTIRE_JOINT: IEntireJoint = {
     impl: null,
 
     initialize: FUNC,
+    apply: FUNC,
 
     setDampingRatio: FUNC,
     setFrequency: FUNC,

cocos/physics-2d/spec/i-physics-joint.ts

@@ -22,15 +22,13 @@
  THE SOFTWARE.
 */
 
-
-
 import { IVec2Like } from '../../core';
 import { ILifecycle } from '../../physics/spec/i-lifecycle';
 import { Joint2D, RigidBody2D } from '../framework';
 
 export interface IJoint2D extends ILifecycle {
     readonly impl: any;
-
+    apply (): void;
     initialize (v: Joint2D): void;
 }