2017-05

http://blog.qt.io/blog/2017/05/24/qt3d/

Qt3D future

    5.9

        Use Qt Quick or QPainter to render into a texture

        Embed Qt Quick into Qt3D, including input handling

        Level of Detail support for meshes

        Text support - 2D and 3D

        Additional materials such as PBR materials

    others

        Generating and filling buffers out of QAbstractItemModels

        Billboards - camera facing entities

        Particle systems

        VR support

    new aspects:

        碰撞检测

        动画：关键帧动画；骨骼动画；Morph target animation; Removes animation workload from main thread

        物理：刚体／柔体物理模拟

        AI:

        三维位置音效：如喇叭，越近越响

    工具

        设计时工具：场景设计器

        Qt 3D Studio

        编译时工具：资产状态监控

    More

        贴图控制

        可yizhi算法（OpenGL）

        各种3d模型的加载

2d ui嵌入到 3d里面用Scene2D

    Scene2D {

        id: qmlTexture

        output: RenderTargetOutput {

            attachmentPoint: RenderTargetOutput.Color0

            texture: Texture2D { id: offscreenTexture }

        }

        entities: [ cube ]

        Item {

            id: customQtQuickStuff

        }

    }

纹理加载器

    TextureLoader {

        source: "qrc:/assets/textures/pbr-default/pbr-default-metallic.png"

        minificationFilter: Texture.LinearMipMapLinear

        magnificationFilter: Texture.Linear

        wrapMode {

            x: WrapMode.ClampToEdge

            y: WrapMode.ClampToEdge

        }

        generateMipMaps: true

    }

新增材质

    粗糙金属材质

        MetalRoughMaterial

    粗糙金属纹理材质

        TexturedMetalRoughMaterial {

            baseColor: TextureLoader {

                format: Texture.SRGB8_Alpha8

                source: "qrc:/assets/powerup/basecolor.png"

            }

            metalness: TextureLoader { source: "qrc:/assets/powerup/metalness.png" }

            roughness: TextureLoader { source: "qrc:/assets/powerup/roughness.png" }

            normal: TextureLoader { source: "qrc:/assets/powerup/normal.png" }

            ambientOcclusion: TextureLoader { source: "qrc:/assets/powerup/ambientocclusion.png" }

        }

新增环境光

    EnvironmentLight {

        id: envLight

        irradiance: TextureLoader {

            source: "qrc:/assets/envmaps/wobbly-bridge/wobbly_bridge_4k" + _envmapFormat + "_cube_irradiance.dds"

            minificationFilter: Texture.LinearMipMapLinear

            magnificationFilter: Texture.Linear

            wrapMode {

                x: WrapMode.ClampToEdge

                y: WrapMode.ClampToEdge

            }

            generateMipMaps: false

        }

        specular: TextureLoader {

            source: "qrc:/assets/envmaps/wobbly-bridge/wobbly_bridge_4k" + _envmapFormat + "_cube_specular.dds"

            minificationFilter: Texture.LinearMipMapLinear

            magnificationFilter: Texture.Linear

            wrapMode {

                x: WrapMode.ClampToEdge

                y: WrapMode.ClampToEdge

            }

            generateMipMaps: false

        }

    }

天空盒实体

    SkyboxEntity {

        baseName: "qrc:/assets/envmaps/wobbly-bridge/wobbly_bridge_4k" + _envmapFormat + "_cube_radiance"

        extension: ".dds"

        gammaCorrect: true

    }            

相机增加曝光度属性

    Camera {

        id: mainCamera

        position: Qt.vector3d(-10, 0, 0)

        viewCenter: Qt.vector3d(0, 0, 0)

        exposure: 1.4  // 曝光度

    }

加载预设的动画

    import Qt3D.Animation 2.9

    ClipAnimator {

        id: animator

        loops: 3

        clip: AnimationClipLoader { source: "qrc:/jumpinganimation.json" }

        channelMapper: ChannelMapper {

            mappings: [

                ChannelMapping { channelName: "Location"; target: cubeTransform; property: "translation" },

                ChannelMapping { channelName: "Rotation"; target: cubeTransform; property: "rotation" },

                ChannelMapping { channelName: "Scale"; target: cubeTransform; property: "scale3D" }

            ]

        }

    }

对象选择器

    ObjectPicker { onClicked: animator.running = true;}

根据远近来动态调整场景（volumeOverride）

    LevelOfDetail

        Entity {

            components: [

                CylinderMesh {

                    radius: 1

                    length: 3

                    rings: 2

                    slices: sliceValues[lod.currentIndex]

                    property var sliceValues: [20, 10, 6, 4]

                },

                Transform {

                    rotation: fromAxisAndAngle(Qt.vector3d(1, 0, 0), 45)

                },

                PhongMaterial {

                    diffuse: "lightgreen"

                },

                LevelOfDetail {

                    id: lod

                    camera: camera

                    thresholds: [1000, 600, 300, 180]

                    thresholdType: LevelOfDetail.ProjectedScreenPixelSizeThreshold

                    volumeOverride: lod.createBoundingSphere(Qt.vector3d(0, 0, 0), 2.0)

                }

            ]

        }

    LevelOfDetailSwitch

        Entity {

            components: [

                LevelOfDetailSwitch {

                    camera: camera

                    thresholds: [20, 35, 50]

                    thresholdType: LevelOfDetail.DistanceToCameraThreshold

                }

            ]

            HighDetailEntity { enabled: false }

            MediumDetailEntity { enabled: false }

            LowDetailEntity { enabled: false }

        }

    LevelOfDetailLoader

        LevelOfDetailLoader {

            id: lodLoader

            camera: camera

            thresholds: [20, 35, 50]

            thresholdType: LevelOfDetail.DistanceToCameraThreshold

            volumeOverride: lodLoader.createBoundingSphere(Qt.vector3d(0, 0, 0), -1)

            sources: ["qrc:/HighDetailEntity.qml", "qrc:/MediumDetailEntity.qml", "qrc:/LowDetailEntity.qml"]

        }

渲染文本

    Text2DEntity

        Text2DEntity {

            id: text

            text: "Hello World"

            width: 20

            height: 10

        }

    ExtrudedTextMesh

        auto *text = new Qt3DCore::QEntity(root);

        auto *textTransform = new Qt3DCore::QTransform();

        auto *textMesh = new Qt3DExtras::QExtrudedTextMesh();

        textMesh->setDepth(.45f);

        QFont font(family, 32, -1, false);

        textMesh->setFont(font);

        textMesh->setText(QString(family));

        auto *textMaterial = new Qt3DExtras::QPhongMaterial(root);

        textMaterial->setDiffuse(QColor(111, 150, 255));

        text->addComponent(textTransform);

        text->addComponent(textMesh);

        text->addComponent(textMaterial);