How to zoom in/out or resize a 3D model rendered in QML from a .obj file

[rahulch_pp]

I am trying to implement a basic QML application that loads a 3D model from a .obj file and just display it on the screen. For now I am able to do so, but the object displayed is far too small. Is there a way to stretch/resize the model while rendering to fit its parent window's size or something?

Here is the code -

import Qt3D.Core 2.12
import Qt3D.Render 2.12
import Qt3D.Extras 2.12
import Qt3D.Input 2.12
import QtQuick.Scene3D 2.12
import QtQuick 2.12 as QQ2

Scene3D {
    id: scene3d
    anchors.fill: parent
    focus: true
    aspects: ["input", "logic"]
    height: parent.height
    width: parent.width
    cameraAspectRatioMode: Scene3D.AutomaticAspectRatio
    Entity {
        id: sceneRoot

        Camera {
            id: camera
            projectionType: CameraLens.PerspectiveProjection
            fieldOfView: 45
            nearPlane: 0.1
            farPlane: 1000.0
            position: Qt.vector3d(0.0, 0.0, 40.0)
            upVector: Qt.vector3d(0.0, 1.0, 0.0)
            viewCenter: Qt.vector3d(0.0, 0.0, 0.0)
        }

        FirstPersonCameraController {
            camera: camera
        }

        components: [
            RenderSettings {
                activeFrameGraph: ForwardRenderer {
                    camera: camera
                    clearColor: "transparent"
                }
            },
            InputSettings {
                id: inputSettings
            }
        ]

        PhongMaterial {
            id: material
        }

        Mesh {
            id: sphereMesh
//             source: "images/face3d/face_bse_mesh.obj"
            source: "images/robo-obj-pose4/source/d2f0cff60afc40f5afe79156ec7db657.obj"
        }

        Transform {
            id: modelTransform
            property real userAngle: 0.0
            matrix: {
                var m = Qt.matrix4x4()
                m.rotate(userAngle, Qt.vector3d(0, 1, 0))
//                 m.translate(Qt.vector3d(20, 0, 0))
                return m
            }
        }
        
        QQ2.NumberAnimation {
            target: modelTransform
            property: "userAngle"
            duration: 10000
            from: 0
            to: 360
            
            loops: QQ2.Animation.Infinite
            running: true
        }
        
        Entity {
            id: sphereEntity
            components: [sphereMesh, material, modelTransform]
        }
    
        OrbitCameraController{
            id: orbitCamera
            camera: camera
        }
    }
}