Qt Quick 3D - Custom Effect Example

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 import QtQuick
 import QtQuick3D
 import QtQuick3D.Helpers
 import QtQuick3D.Effects
 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 on uRed {
                 running: radioEff2.checked || radioEff3.checked
                 loops: -1
                 NumberAnimation { from: 0; to: 1; duration: 2000 }
                 NumberAnimation { 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 on uGreen {
                 running: radioEff4.checked
                 loops: -1
                 NumberAnimation { from: 0; to: 1; duration: 2000 }
                 NumberAnimation { 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 ]
         }
         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 = [];
             }
         }
     }
 }