feat: add rotateAxisAngle for Quaternion (galacean#480)

* feat: add rotateAxisAngle for Quaternion
luzhuang · Sep 7, 2021 · b317f3b · b317f3b
1 parent 9d8feae
commit b317f3b
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Showing 2 changed files with 23 additions and 1 deletion.
diff --git a/packages/math/src/Quaternion.ts b/packages/math/src/Quaternion.ts
@@ -9,6 +9,8 @@ import { Vector3 } from "./Vector3";
 export class Quaternion implements IClone {
   /** @internal */
   static readonly _tempVector3 = new Vector3();
+  /** @internal */
+  static readonly _tempQuat1 = new Quaternion();
 
   /**
    * Determines the sum of two quaternions.
@@ -697,4 +699,16 @@ export class Quaternion implements IClone {
     Quaternion.lerp(this, quat, t, this);
     return this;
   }
+
+  /**
+   * Calculate this quaternion rotation around an arbitrary axis.
+   * @param axis - The axis
+   * @param rad - The rotation angle in radians
+   * @returns This quaternion
+   */
+  rotateAxisAngle(axis: Vector3, rad: number): Quaternion {
+    Quaternion._tempQuat1.rotationAxisAngle(axis, rad);
+    this.multiply(Quaternion._tempQuat1);
+    return this;
+  }
 }
diff --git a/packages/math/tests/Quaternion.test.ts b/packages/math/tests/Quaternion.test.ts
@@ -177,6 +177,14 @@ describe("Quaternion test", () => {
     expect(Quaternion.equals(out, b)).toEqual(true);
   });
 
+  it("static rotatAxisAngle", () => {
+    const a = new Vector3(0, 5, 0);
+    const b = 0.5 * Math.PI;
+    const out = new Quaternion(0, 0, 0, 1);
+    out.rotateAxisAngle(a, b);
+    expect(Quaternion.equals(out, new Quaternion(0, 0.7071067811865475, 0, 0.7071067811865476))).toEqual(true);
+  });
+
   it("static scale", () => {
     const a = new Quaternion(3, 4, 5, 0);
     const out = new Quaternion();
@@ -200,7 +208,7 @@ describe("Quaternion test", () => {
     const b = new Quaternion();
     b.setValueByArray([1, 1, 1, 1]);
     expect(Quaternion.equals(a, b)).toEqual(true);
-    
+
     const c = [];
     b.toArray(c);
     const d = new Quaternion();