Qt Quick 3D - Lights Example

Image non disponible

This example demonstrates using three different light types in an application.

Setting the Scene Lights

 

Directional Light

The directional light emits light in one direction from an unidentifiable source located infinitely far away. This is similar to the way sunlight works in real life. A directional light has infinite range and does not diminish.

We setup directional light to emit red color and animate its rotation around x-axis.

 
Sélectionnez
DirectionalLight {
    id: light1
    color: Qt.rgba(1.0, 0.1, 0.1, 1.0)
    ambientColor: Qt.rgba(0.1, 0.1, 0.1, 1.0)
    position: Qt.vector3d(0, 200, 0)
    rotation: Quaternion.fromEulerAngles(-135, -90, 0)
    shadowMapQuality: Light.ShadowMapQualityHigh
    visible: checkBox1.checked
    castsShadow: checkBoxShadows.checked
    brightness: slider1.sliderValue
    SequentialAnimation on rotation {
        loops: Animation.Infinite
        QuaternionAnimation {
            to: Quaternion.fromEulerAngles(-45, -90, 0)
            duration: 2000
            easing.type: Easing.InOutQuad
        }
        QuaternionAnimation {
            to: Quaternion.fromEulerAngles(-135, -90, 0)
            duration: 2000
            easing.type: Easing.InOutQuad
        }
    }
}

Point Light

The point light can be described as a sphere, emitting light with equal strength in all directions from the center of the light. This is similar to the way a light bulb emits light.

We setup point light to emit green color and animate its position in x-coordinate.

 
Sélectionnez
PointLight {
    id: light2
    color: Qt.rgba(0.1, 1.0, 0.1, 1.0)
    ambientColor: Qt.rgba(0.1, 0.1, 0.1, 1.0)
    position: Qt.vector3d(0, 300, 0)
    shadowMapFar: 2000
    shadowMapQuality: Light.ShadowMapQualityHigh
    visible: checkBox2.checked
    castsShadow: checkBoxShadows.checked
    brightness: slider2.sliderValue
    SequentialAnimation on x {
        loops: Animation.Infinite
        NumberAnimation {
            to: 400
            duration: 2000
            easing.type: Easing.InOutQuad
        }
        NumberAnimation {
            to: 0
            duration: 2000
            easing.type: Easing.InOutQuad
        }
    }
}

Spot Light

The spot light is similar to the point light, except that it emits light in a cone shape towards one direction instead of all directions. Aside from the cone angle, a spot light has the same characteristics and properties as the point light.

We setup spot light to emit a warm color and animate its rotation in y-coordinate.

 
Sélectionnez
SpotLight {
    id: light4
    color: Qt.rgba(1.0, 0.9, 0.7, 1.0)
    ambientColor: Qt.rgba(0.0, 0.0, 0.0, 0.0)
    position: Qt.vector3d(0, 250, 0)
    eulerRotation.x: -45
    shadowMapFar: 2000
    shadowMapQuality: Light.ShadowMapQualityHigh
    visible: checkBox4.checked
    castsShadow: checkBoxShadows.checked
    brightness: slider4.sliderValue
    coneAngle: 50
    innerConeAngle: 30
    PropertyAnimation on eulerRotation.y {
        loops: Animation.Infinite
        from: 0
        to: -360
        duration: 10000
    }
}

Setting the Scene Models

First we add two rectangle models to act as the floor and the back wall for our scene. These are useful for seeing light shadows.

 
Sélectionnez
Model {
    source: "#Rectangle"
    y: -200
    scale: Qt.vector3d(15, 15, 15)
    eulerRotation.x: -90
    materials: [
        DefaultMaterial {
            diffuseColor: Qt.rgba(0.8, 0.6, 0.4, 1.0)
        }
    ]
}
Model {
    source: "#Rectangle"
    z: -400
    scale: Qt.vector3d(15, 15, 15)
    materials: [
        DefaultMaterial {
            diffuseColor: Qt.rgba(0.8, 0.8, 0.9, 1.0)
        }
    ]
}

Then we add our main teapot model which is rotated around y-axis.

 
Sélectionnez
Model {
    id: teapotDefault
    source: "teapot.mesh"
    y: -100
    scale: Qt.vector3d(75, 75, 75)

    property variant material
    materials: [ material ]

    property bool animate: true
    NumberAnimation on eulerRotation.y {
        running: animate
        loops: Animation.Infinite
        duration: 5000
        from: 0
        to: -360
    }
}

We also add small cube models to demonstrate position & rotation of each light type. These cubes scale bigger when user is accessing related sliders.

 
Sélectionnez
Model {
    source: "#Cube"
    position: light1.position
    rota