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import Qt3D.Core 2.0
import Qt3D.Render 2.0
import Qt3D.Input 2.0
import Qardboard 1.0

Entity {
    id: root
    property alias fieldOfView: stereoCamera.fieldOfView
    property alias cameraPosition: stereoCamera.position
    property alias cameraDirection: stereoCamera.viewDirection
    property alias headlightDirection: headLight.worldDirection

    components: [
        RenderSettings {
            activeFrameGraph: QardboardFrameGraph {
                id: stereoFrameGraph
                leftCamera: stereoCamera.leftCamera
                rightCamera: stereoCamera.rightCamera
            }
        },
        InputSettings { },
        DirectionalLight {
            id: headLight
            worldDirection: stereoCamera.viewDirection.times(-1)
        }
    ]

    DeviceOrientation {
        id: orientation
        enabled: true
    }

    QardboardCamera {
        id: stereoCamera
        viewMatrix: computeMatrix(orientation.roll, orientation.pitch, orientation.yaw)

        property vector3d vc
        property vector3d vd
        property vector3d vu

        function computeMatrix(roll, pitch, yaw) {
            var m = Qt.matrix4x4()
            m.rotate(-roll, Qt.vector3d(1, 0, 0))
            m.rotate(yaw, Qt.vector3d(0, 1, 0))
            vd = m.times(stereoCamera.viewDirection)
            vu = m.times(stereoCamera.viewUp)
            var r = Qt.matrix4x4()
            vc = stereoCamera.position.minus(vd)
            r.lookAt(stereoCamera.position, vc, vu)
//            console.log(roll.toFixed(2), pitch.toFixed(2), yaw.toFixed(2), stereoCamera.position, vd, vc, vu)
//            console.log(r)
            return r
        }
    }
}
