Why object not shown up in my Qt3D test

[ajee]

Hi all, I am new to Qt3D and want to have a trail for fun.

I get an example and it works with mesh load from toyplane.obj, then I tried with a more complex model building_04.obj, it won't show up although I tried to tune camera with aspectRatio, near or farPlane, position ,etc ( I have to admit I am not familiar with what it means. ). toyplane.obj is got from the official example, building_04.obj is from https://free3d.com/3d-model/buildinghouse-04-40137.html ( I hope to upload files but it said I don't have privilege ).

Thanks for your help.

main.cpp:

#include <Qt3DQuickExtras/qt3dquickwindow.h>
#include <QGuiApplication>

int main(int argc, char* argv[])
{
    QGuiApplication app(argc, argv);
    Qt3DExtras::Quick::Qt3DQuickWindow view;
    view.setSource(QUrl("qrc:/main.qml"));
    view.show();

    return app.exec();
}

main.qml:

import QtQuick 2.2 as QQ2
import Qt3D.Core 2.0
import Qt3D.Render 2.0
import Qt3D.Input 2.0
import Qt3D.Extras 2.0

Entity {
    id: sceneRoot

    Camera {
        id: camera
        projectionType: CameraLens.PerspectiveProjection
        fieldOfView: 100
        aspectRatio: 16/9
        nearPlane : 0.1
        farPlane : 1000.0
        position: Qt.vector3d( 0.0, 0.0, -50.0 )
        upVector: Qt.vector3d( 0.0, 1.0, 0.0 )
        viewCenter: Qt.vector3d( 0.0, 0.0, 0.0 )
    }

    OrbitCameraController {
        camera: camera
    }

    components: [
        RenderSettings {
            activeFrameGraph: ForwardRenderer {
                clearColor: Qt.rgba(0, 0.5, 0.5, 0)
                camera: camera
            }
        },
        // Event Source will be set by the Qt3DQuickWindow
        InputSettings { }
    ]
    PhongMaterial {
        id: material
    }

    Mesh {
        id: myMesh
        //source: "qrc:/toyplane.obj"
        source: "qrc:/building_04.obj"
    }

    Entity {
        id: topplane


        components: [myMesh, material]
    }

}

The result is, with toyplane.obj, it looks like:

With building_o4.obj, nothing but a blank background