- Qt 6.7
- Qt Quick 3D
- Qt Quick 3D Examples and Tutorials
- Qt Quick 3D - Custom Effect Example
- Qt Quick 3D | Commercial or GPLv3

# Qt Quick 3D - Custom Effect Example

     // Copyright (C) 2019 The Qt Company Ltd.
     // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

     import QtQuick
     import QtQuick3D
     import QtQuick3D.Helpers
     import QtQuick.Controls
     import QtQuick.Layouts

     Window {
         id: window
         width: 1280
         height: 720
         visible: true
         title: "Custom Post-Processing Effect Example"
         color: "#848895"

         View3D {
             id: view3d

             Effect {
                 id: eff1
                 property TextureInput tex: TextureInput {
                     id: qtLogo
                     texture: Texture { source: "qt_logo_rect.png" }
                 }
                 passes: Pass {
                     shaders: Shader {
                         id: fs1
                         stage: Shader.Fragment
                         shader: "effect.frag"
                     }
                 }
             }

             Effect {
                 id: eff2
                 property real uRed: 0.0
                 SequentialAnimation {
                     running: radioEff2.checked || radioEff3.checked
                     loops: Animation.Infinite
                     NumberAnimation { target: eff2; property: "uRed"; from: 0; to: 1; duration: 2000 }
                     NumberAnimation { target: eff2; property: "uRed"; from: 1; to: 0; duration: 2000 }
                 }
                 property real uGreen: 1.0
                 Shader {
                     id: vs2
                     stage: Shader.Vertex
                     shader: "effect2.vert"
                 }
                 Shader {
                     id: fs2
                     stage: Shader.Fragment
                     shader: "effect2.frag"
                 }
                 passes: Pass {
                     shaders: [ vs2, fs2 ]
                 }
             }

             Effect {
                 id: eff3

                 property TextureInput tex: qtLogo
                 property real uRed: 1.0
                 property real uGreen: 0.0
                 SequentialAnimation {
                     running: radioEff4.checked
                     loops: Animation.Infinite
                     NumberAnimation { target: eff3; property: "uGreen"; from: 0; to: 1; duration: 2000 }
                     NumberAnimation { target: eff3; property: "uGreen"; from: 1; to: 0; duration: 2000 }
                 }

                 Buffer {
                     id: intermediateTexture
                     name: "intermediateTexture"
                     format: Buffer.RGBA8
                     textureFilterOperation: Buffer.Linear
                     textureCoordOperation: Buffer.ClampToEdge
                     sizeMultiplier: 2 // just for fun upscale and then downscale
                 }

                 passes: [
                     Pass {
                         shaders: [ fs1 ]
                         output: intermediateTexture
                     },
                     Pass {
                         shaders: [ vs2, fs2 ]
                         commands: [
                             BufferInput {
                                 buffer: intermediateTexture
                             }
                         ]
                     }
                 ]
             }

             anchors.fill: parent
             renderMode: View3D.Offscreen

             environment: SceneEnvironment {
                 id: env
                 clearColor: "skyblue"
                 backgroundMode: SceneEnvironment.Color
                 effects: [ eff1 ]
             }

             PerspectiveCamera {
                 id: camera
                 position: Qt.vector3d(0, 200, 300)
                 eulerRotation.x: -20
             }

             DirectionalLight {
                 eulerRotation.x: -20
                 eulerRotation.y: 20
                 ambientColor: Qt.rgba(0.8, 0.8, 0.8, 1.0);
             }

             Texture {
                 id: checkers
                 source: "checkers2.png"
                 scaleU: 20
                 scaleV: 20
                 tilingModeHorizontal: Texture.Repeat
                 tilingModeVertical: Texture.Repeat
             }

             Model {
                 source: "#Rectangle"
                 scale.x: 10
                 scale.y: 10
                 eulerRotation.x: -90
                 materials: [ DefaultMaterial { diffuseMap: checkers } ]
             }

             Model {
                 source: "#Cone"
                 position: Qt.vector3d(100, 0, -200)
                 scale.y: 3
                 materials: [ DefaultMaterial { diffuseColor: "green" } ]
             }

             Model {
                 id: sphere
                 source: "#Sphere"
                 position: Qt.vector3d(-100, 200, -200)
                 materials: [ DefaultMaterial { diffuseColor: "#808000" } ]
             }

             Model {
                 source: "#Cube"
                 position.y: 50
                 eulerRotation.y: 20
                 materials: [ DefaultMaterial { diffuseColor: "gray" } ]
             }
         }

         WasdController {
             controlledObject: camera
         }

         ColumnLayout {
             Label {
                 text: "Use WASD and mouse to navigate"
                 font.bold: true
             }
             ButtonGroup {
                 buttons: [ radioEff1, radioEff2, radioEff3, radioEff4, radioEff5 ]
             }
             // qmllint disable read-only-property
             // QTBUG-114144
             RadioButton {
                 id: radioEff1
                 text: "Custom effect with fragment shader only"
                 checked: true
                 focusPolicy: Qt.NoFocus
                 onCheckedChanged: {
                     if (checked)
                         env.effects = [ eff1 ];
                 }
             }
             RadioButton {
                 id: radioEff2
                 text: "Custom effect with vertex and fragment shaders"
                 checked: false
                 focusPolicy: Qt.NoFocus
                 onCheckedChanged: {
                     if (checked)
                         env.effects = [ eff2 ];
                 }
             }
             RadioButton {
                 id: radioEff3
                 text: "Both effects chained"
                 checked: false
                 focusPolicy: Qt.NoFocus
                 onCheckedChanged: {
                     if (checked)
                         env.effects = [ eff1, eff2 ];
                 }
             }
             RadioButton {
                 id: radioEff4
                 text: "As one single, multi-pass effect"
                 checked: false
                 focusPolicy: Qt.NoFocus
                 onCheckedChanged: {
                     if (checked)
                         env.effects = [ eff3 ];
                 }
             }
             RadioButton {
                 id: radioEff5
                 text: "No effects"
                 checked: false
                 focusPolicy: Qt.NoFocus
                 onCheckedChanged: {
                     if (checked)
                         env.effects = [];
                 }
             }
             // qmllint disable read-only-property
         }
     }