[LayaAir 2.0]Laya.BlinnPhongMaterial.RENDERMODE_TRANSPARENT设置透明度不行了？

var box: Laya.MeshSprite3D = scene.addChild(new Laya.MeshSprite3D(Laya.PrimitiveMesh.createBox(1, 1, 1))) as Laya.MeshSprite3D;
        box.transform.rotate(new Laya.Vector3(0, 45, 0), false, false);
        var material: Laya.BlinnPhongMaterial = new Laya.BlinnPhongMaterial();
        Laya.Texture2D.load("res/layabox.png", Laya.Handler.create(null, function (tex: Laya.Texture2D) {
            material.albedoTexture = tex;
        }));
        material.albedoColor = new Laya.Vector4(1.0, 1.0, 1.0, 0.5);
        material.renderMode = Laya.BlinnPhongMaterial.RENDERMODE_TRANSPARENT;
        box.meshRenderer.material = material;