Merge pull request galacean#2464 from cptbtptpbcptdtptp/feat/transform

Replace `Transform`

Author: GuoLei1990

packages/core/src/ComponentsDependencies.ts

@@ -39,7 +39,13 @@ export class ComponentsDependencies {
    * @internal
    */
   static _removeCheck(entity: Entity, type: ComponentConstructor): void {
+    const components = entity._components;
+    const n = components.length;
     while (type !== Component) {
+      let count = 0;
+      for (let i = 0; i < n; i++) {
+        if (components[i] instanceof type && ++count > 1) return;
+      }
       const invDependencies = ComponentsDependencies._invDependenciesMap.get(type);
       if (invDependencies) {
         for (let i = 0, len = invDependencies.length; i < len; i++) {

packages/core/src/Entity.ts

@@ -97,9 +97,8 @@ export class Entity extends EngineObject {
   _isTemplate: boolean = false;
   /** @internal */
   _updateFlagManager: UpdateFlagManager = new UpdateFlagManager();
-  /** @internal */
-  _transform: Transform;
 
+  private _transform: Transform;
   private _templateResource: ReferResource;
   private _parent: Entity = null;
   private _activeChangedComponents: Component[];
@@ -227,6 +226,13 @@ export class Entity extends EngineObject {
     ComponentsDependencies._addCheck(this, type);
     const component = new type(this, ...args) as InstanceType<T>;
     this._components.push(component);
+
+    // @todo: temporary solution
+    if (component instanceof Transform) {
+      const transform = this._transform;
+      this._transform = component;
+      transform?.destroy();
+    }
     component._setActive(true, ActiveChangeFlag.All);
     return component;
   }

packages/core/src/Transform.ts

@@ -3,6 +3,7 @@ import { BoolUpdateFlag } from "./BoolUpdateFlag";
 import { Component } from "./Component";
 import { Entity } from "./Entity";
 import { assignmentClone, deepClone, ignoreClone } from "./clone/CloneManager";
+import { Logger } from "./base";
 
 /**
  * Used to implement transformation related functions.
@@ -340,12 +341,6 @@ export class Transform extends Component {
     this._worldRotationQuaternion._onValueChanged = this._onWorldRotationQuaternionChanged;
     //@ts-ignore
     this._scale._onValueChanged = this._onScaleChanged;
-
-    if (entity._transform) {
-      throw `Entity already has a transform.`;
-    } else {
-      entity._transform = this;
-    }
   }
 
   /**

tests/src/core/Transform.test.ts

@@ -98,12 +98,17 @@ describe("Transform test", function () {
     expect((entity5.transform as SubClassOfTransform).size).to.deep.include({ x: 100, y: 100 });
 
     // Add component
-    expect(() => {
-      entity0.addComponent(SubClassOfTransform);
-    }).to.throw("Entity already has a transform.");
-    expect(() => {
-      entity1.addComponent(Transform);
-    }).to.throw("Entity already has a transform.");
+    const preTransform0 = entity0.transform;
+    entity0.addComponent(SubClassOfTransform);
+    expect(preTransform0.destroyed).to.equal(true);
+    expect(entity0.transform instanceof Transform).to.equal(true);
+    expect(entity0.transform instanceof SubClassOfTransform).to.equal(true);
+
+    const preTransform1 = entity1.transform;
+    entity1.addComponent(Transform);
+    expect(preTransform1.destroyed).to.equal(true);
+    expect(entity1.transform instanceof Transform).to.equal(true);
+    expect(entity1.transform instanceof SubClassOfTransform).to.equal(false);
   });
 });