移动相机时在模型上绘制文本

Question

我希望能够在模型之上绘制文字。

我有一个像下面这样的场景;

我希望能够在绿线顶部添加文字。但是，我无法使用正确的投影显示2d文本。我有一个移动的摄像头，中间的车也在移动。

spriteBatch.setProjectionMatrix(camera.combined);

这使文本出现在相机的背面（意味着较小的z值）。我把所有的车都放在了Vector3。我有侧面代码的以下代码;

public class SideCar extends Car {

  public enum Side {
    LEFT, RIGHT
  }

  protected Side side;
  protected String plate;
  protected ShapeRenderer shapeRenderer;
  protected Vector3 sideCarV3;
  protected Texture texture;

  public SideCar(AssetManager assetManager, Side side, String plate) {

    super(assetManager);
    this.id = "side_car";
    this.side = side;
    this.plate = plate;

    if (side == Side.LEFT) {
      instance.transform.translate(-35f, 0f, 10f);
    } else { // right
      instance.transform.translate(35f, 0f, 10f);
    }

    shapeRenderer = new ShapeRenderer();
    shapeRenderer.setColor(Color.GREEN);

    sideCarV3 = new Vector3();

    texture = new Texture(Gdx.files.internal("data/font/avenir.png"), true); // true enables mipmaps
    texture.setFilter(Texture.TextureFilter.MipMapLinearNearest, Texture.TextureFilter.Linear);
  }

  @Override
  public void renderModel(float deltaTime, Scene scene) {

    super.renderModel(deltaTime, scene);
    scene.modelBatch().render(instance, scene.environment());
    //scene.modelBatch().render(texture, scene.environment());

    // public final void line (float x, float y, float z, float x2, float y2, float z2)
    sideCarV3 = instance.transform.getTranslation(sideCarV3);

    shapeRenderer.begin(ShapeRenderer.ShapeType.Line);
    shapeRenderer.setProjectionMatrix(scene.camera().combined);
    shapeRenderer.identity();

    if (side == Side.LEFT) {
      shapeRenderer.line(2.5f, 0f, sideCarV3.z, 2.5f, 1.5f, sideCarV3.z);
      shapeRenderer.line(2.5f, 1.5f, sideCarV3.z, 2.4f, 1.5f, sideCarV3.z);
    } else {
      shapeRenderer.line(-2.5f, 0f, sideCarV3.z, -2.5f, 1.5f, sideCarV3.z);
      shapeRenderer.line(-2.5f, 1.5f, sideCarV3.z, -2.4f, 1.5f, sideCarV3.z);
    }

    shapeRenderer.end();

  }

  @Override
  public void renderSprite(float deltaTime, Scene scene) {

    instance.transform.getTranslation(sideCarV3);

    if (side == Side.LEFT) {

    } else {
      infoFont.draw(
          scene.spriteBatch(),
          String.format(Locale.US, "%d km/h", (int) (speed * 100)), sideCarV3.x, sideCarV3.y + 5f
      );
    }
  }
}

任何想法将文本放在绿线顶部的想法？