如何在 Qt3D 中改变光线答案

【问题标题】：How to change light in Qt3D如何在 Qt3D 中改变光线
【发布时间】：2016-09-09 00:22:22
【问题描述】：

如何更改 Qt3D 中的灯光设置？

我认为应该是framegraph的一部分，但是标准的forwardrenderer中没有任何与灯光设置相关的方法。

【问题讨论】：

标签： qt qt3d

【解决方案1】：

其中 rootEntity 是场景中所有其他实体的父级。

Qt3DCore::QEntity *lightEntity = new Qt3DCore::QEntity(rootEntity);
Qt3DRender::QPointLight *light = new Qt3DRender::QPointLight(lightEntity);
light->setColor("white");
light->setIntensity(1.);
lightEntity->addComponent(light);

【讨论】：

【解决方案2】：

据我所知，没有直接的灯光设置。

您要做的是创建一个聚光灯并对其进行调整。

来自 Qt3D 示例：

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import Qt3D 2.0
import Qt3D.Renderer 2.0

Entity {
    id: root

    property vector3d lightPosition: Qt.vector3d(30.0, 30.0, 0.0)
    property vector3d lightIntensity: Qt.vector3d(1.0, 1.0, 1.0)

    readonly property Camera lightCamera: lightCamera
    readonly property matrix4x4 lightViewProjection: lightCamera.projectionMatrix.times(lightCamera.matrix)

    Camera {
        id: lightCamera
        objectName: "lightCameraLens"
        projectionType: CameraLens.PerspectiveProjection
        fieldOfView: 45
        aspectRatio: 1
        nearPlane : 0.1
        farPlane : 200.0
        position: root.lightPosition
        viewCenter: Qt.vector3d(0.0, 0.0, 0.0)
        upVector: Qt.vector3d(0.0, 1.0, 0.0)
    }
}

Full example to light and shadows

除此之外还有QDirectionalLight和QPointLight。

【讨论】：