从Matrix4转换为Vec3，Quaternion，Vec3，然后再返回

Question

Libgdx使用Matrix4来表示对象的世界空间位置，旋转和缩放。

当我在我的代码中动画这些对象时，我希望将它们转换为保持位置，旋转和缩放分离的格式。 这样可以更容易地进行正确插值，以便为它们设置动画。

我将Scale和Position存储为Vector3s。 而旋转为四元数。

这是我的类，它存储这3个并转换为2和Matrix4;

public class PosRotScale {

	private static String logstag="ME.PosRotScale";
	
	Vector3 position = new Vector3();
	Quaternion rotation = new Quaternion();		
	Vector3 scale = new Vector3(1f,1f,1f);
	
	public PosRotScale(Vector3 position, Quaternion rotation, Vector3 scale) {
		super();
		
		this.position = position;
		this.rotation = rotation;
		this.scale = scale;
		
	}

    public PosRotScale(Matrix4 setToThis) {
		
		this.setToMatrix(setToThis);		
		
	}

	@Override
	public String toString(){
		
		Vector3 axis = new Vector3();
		float angle = rotation.getAxisAngle(axis);
		
		
		String stateAsString = "["+position.x+","+position.y+","+position.z+"]"
				             + "["+axis.x+","+axis.y+","+axis.z+","+angle+"]"
				             + "["+scale.x+","+scale.y+","+scale.z+"]";
		
		return stateAsString;
		
		
	}

	
	public void setToMatrix(Matrix4 lastLocation) {
		
		lastLocation.getTranslation(position); 
		lastLocation.getRotation(rotation);
		lastLocation.getScale(scale); 
		
	}


    public PosRotScale setToRotation(float i, float j, float k, float angleInDeg) {
		rotation.set(new Vector3(i,j,k), angleInDeg);    		
		
		return this;
	}

	
	public PosRotScale setToPosition(Vector3 newposition) {
		position = newposition.cpy();

		return this;
	}

	
	public PosRotScale setToScaling(Vector3 newscale) {
		scale = newscale.cpy();
		
		return this;
	}

	public Matrix4 createMatrix() {
		return  new Matrix4(position,rotation.nor(),scale);
	}
	
	
	
}

（我为上面的代码段“道歉”并被解释为javascript道歉 - 我没有在Java的代码片段框中看到一个选项）

无论如何，为了测试这是否有效，我创建了一个测试状态并转换为它。 不幸的是，这些价值显然不匹配。 我预计旋转会稍微偏离（似乎是旋转的性质），但是规模显然是谨慎的。关于我做错了什么的指示？

测试代码;

    PosRotScale startScaleAndRotation = new PosRotScale();
    startScaleAndRotation.setToPosition(new Vector3(30f, 40f, 50f));
    startScaleAndRotation.setToRotation(0f, 0f, 1f, 45);
    startScaleAndRotation.setToScaling(new Vector3(0.5f, 2.5f,0.5f));
    Gdx.app.log(logstag, " setting to: "+startScaleAndRotation.toString()); 
    Matrix4 test = startScaleAndRotation.createMatrix();
    PosRotScale test2 = new PosRotScale(test);
    Gdx.app.log(logstag, " check after conversion: "+test2.toString()); 

结果：

setting to: [30.0,40.0,50.0][0.0,0.0,0.99999994,45.000004][0.5,2.5,0.5]
check after conversion: [30.0,40.0,50.0][0.0,0.0,1.811493,35.83953][1.8027757,1.8027754,0.5]