- Qt 6.5
- Qt Quick 3D
- Qt Quick 3D Examples and Tutorials
- Qt Quick 3D - Principled Material Example
- Qt Quick 3D | Commercial or GPLv3

# Qt Quick 3D - Principled Material Example

     // Copyright (C) 2022 The Qt Company Ltd.
     // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

     import QtQuick
     import QtQuick.Controls
     import QtQuick.Layouts
     import QtQuick3D
     import QtQuick.Dialogs

     import Example

     RowLayout {
         id: root
         property Texture targetTexture: null
         property bool stampMode: false
         required property url defaultTexture
         property url stampSource: ""
         property alias defaultClearColor: drawer.clearColor
         property bool envMapMode: false

         GroupBox {
             title: "Image Source Mode"
             ColumnLayout {
                 RadioButton {
                     id: noTextureChoice
                     text: "None"
                     checked: true
                     onCheckedChanged: {
                         targetTexture = null
                     }
                 }
                 RadioButton {
                     id: selectTextureChoice
                     text: "Texture"
                     checked: false
                     onCheckedChanged: targetTexture = selectedTexture
                 }
                 RadioButton {
                     id: loadImageChoice
                     text: "Load Image"
                     onCheckedChanged: targetTexture = loadTextureTexture
                 }
                 RadioButton {
                     id: drawerChoice
                     text: "Draw Texture"
                     onCheckedChanged: targetTexture = drawerTexture
                 }
             }
         }
         Item {
             visible: selectTextureChoice.checked
             width: 256
             height: 256
             Image {
                 id: previewImage
                 anchors.fill: parent
                 sourceSize.width: width
                 sourceSize.height: height
                 fillMode: Image.PreserveAspectFit
                 source: root.defaultTexture
                 Texture {
                     id: selectedTexture
                     source: root.defaultTexture
                     mappingMode: envMapMode ? Texture.Environment : Texture.UV
                 }
             }
         }

         Rectangle {
             id: loadTextureFrame
             width: 256
             height: 256
             color: "transparent"
             border.color: "black"
             visible: loadImageChoice.checked
             property url textureSource: ""
             Text {
                 anchors.centerIn: parent
                 text: "[Load Image]"
             }
             Image {
                 anchors.fill: parent
                 sourceSize.width: width
                 sourceSize.height: height
                 fillMode: Image.PreserveAspectFit
                 visible: loadTextureFrame.textureSource !== null
                 source: loadTextureFrame.textureSource
             }

             MouseArea {
                 anchors.fill: parent
                 onClicked: {
                     textureSourceDialog.open()
                 }
             }

             Texture {
                 id: loadTextureTexture
                 source: loadTextureFrame.textureSource
                 mappingMode: envMapMode ? Texture.Environment : Texture.UV
             }

             ImageHelper {
                 id: imageHelper
             }

             FileDialog {
                 id: textureSourceDialog
                 title: "Open an Image File"
                 nameFilters: [ imageHelper.getSupportedImageFormatsFilter()]
                 onAccepted: {
                     if (textureSourceDialog.selectedFile !== null) {
                         loadTextureFrame.textureSource = textureSourceDialog.selectedFile
                     }
                 }
             }

         }
         ColumnLayout {
             visible: drawerChoice.checked
             Rectangle {
                 width: 260
                 height: 260
                 color: "transparent"
                 border.color: "black"
                 Canvas {
                     id: drawer
                     width: 256
                     height: 256
                     x: 2
                     y: 2

                     property color penColor: "blue"
                     property real penWidth: penWidthSlider.value
                     property bool needsClear: true
                     property color clearColor: "white"
                     property var commands: []
                     property var stampCommands: []
                     property bool stampMode: root.stampMode
                     //property point prevPoint : Qt.point(0, 0)

                     onPaint: {
                         let ctx = getContext('2d');
                         if (needsClear) {
                             ctx.fillStyle = Qt.rgba(clearColor.r, clearColor.g, clearColor.b, clearColor.a);
                             ctx.fillRect(0, 0, width, height)
                             needsClear = false;
                         }
                         if (!stampMode) {
                             ctx.strokeStyle = Qt.rgba(penColor.r, penColor.g, penColor.b, penColor.a)
                             ctx.lineCap = "round"
                             ctx.lineWidth = penWidth;

                             for (let i = 0; i < commands.length; ++i) {
                                 let command = commands[i];
                                 ctx.beginPath()
                                 ctx.moveTo(command.start.x, command.start.y);
                                 ctx.lineTo(command.end.x, command.end.y);
                                 ctx.stroke();
                             }
                             commands = [];
                         } else {
                             for (let i = 0; i < stampCommands.length; ++i) {
                                 let stampCommand = stampCommands[i]
                                 // get offset
                                 let dX = stampCommand.x - stampcursor.width * 0.5
                                 let dY = stampCommand.y - stampcursor.height * 0.5
                                 ctx.drawImage(stampcursor, dX, dY)
                             }
                             stampCommands = [];
                         }
                     }
                 }

                 MouseArea {
                     id: mouseArea
                     anchors.fill: drawer
                     enabled: drawerChoice.checked
                     hoverEnabled: true
                     //acceptedButtons: Qt.LeftButton
                     property bool isDrawing: false
                     property var lastPosition: Qt.point(0, 0)
                     preventStealing: true
                     clip: true

                     Item {
                         id: cursor
                         Rectangle {
                             anchors.centerIn: parent
                             visible: !root.stampMode
                             width: drawer.penWidth
                             height: drawer.penWidth
                             radius: width * 0.5
                             color: drawer.penColor
                         }

                         Image {
                            id: stampcursor
                            anchors.centerIn: parent
                            visible: root.stampMode
                            source: root.stampSource
                         }
                     }

                     onEntered: cursor.visible = true
                     onExited: cursor.visible = false

                     onPressed: (mouse)=> {
                                    if (mouse.button === Qt.LeftButton && !root.stampMode) {
                                        lastPosition = Qt.point(mouse.x, mouse.y)
                                        isDrawing = true
                                    }
                                }
                     onPositionChanged: (mouse)=> {
                                            if (isDrawing) {
                                                let pos = Qt.point(mouse.x, mouse.y);
                                                let command = {"start": lastPosition, "end": pos}
                                                drawer.commands.push(command)
                                                lastPosition = pos;
                                                drawer.requestPaint();
                                            }
                                            cursor.x = mouse.x
                                            cursor.y = mouse.y
                                        }
                     onReleased: (mouse)=> {
                                     if (mouse.button === Qt.LeftButton && isDrawing) {
                                         let pos = Qt.point(mouse.x, mouse.y);
                                         let command = {"start": lastPosition, "end": pos}
                                         drawer.commands.push(command)
                                         isDrawing = false;
                                         drawer.requestPaint();
                                     } else if (stampMode) {
                                         drawer.stampCommands.push(Qt.point(mouse.x, mouse.y));
                                         drawer.requestPaint();
                                     }
                                 }
                 }

             }
             RowLayout {
                 visible: !root.stampMode
                 spacing: 0
                 Rectangle {
                     id: whiteBrush
                     width: 25
                     height: 25
                     color: "white"
                     border.color: "black"
                     MouseArea {
                         anchors.fill: parent
                         onClicked: {
                             drawer.penColor = parent.color;
                         }
                     }
                 }
                 Rectangle {
                     id: blackBrush
                     width: 25
                     height: 25
                     color: "black"
                     border.color: "black"
                     MouseArea {
                         anchors.fill: parent
                         onClicked: {
                             drawer.penColor = parent.color;
                         }
                     }
                 }
                 Rectangle {
                     id: redBrush
                     width: 25
                     height: 25
                     color: "red"
                     border.color: "black"
                     MouseArea {
                         anchors.fill: parent
                         onClicked: {
                             drawer.penColor = parent.color;
                         }
                     }
                 }
                 Rectangle {
                     id: greenBrush
                     width: 25
                     height: 25
                     color: "green"
                     border.color: "black"
                     MouseArea {
                         anchors.fill: parent
                         onClicked: {
                             drawer.penColor = parent.color;
                         }
                     }
                 }
                 Rectangle {
                     id: blueBrush
                     width: 25
                     height: 25
                     color: "blue"
                     border.color: "black"
                     MouseArea {
                         anchors.fill: parent
                         onClicked: {
                             drawer.penColor = parent.color;
                         }
                     }
                 }
                 Label {
                     text: " "

                 }

                 Button {
                     text: "Clear"
                     onClicked: {

                         drawer.needsClear = true
                         drawer.requestPaint()
                     }
                 }

             }
             RowLayout {
                 visible: !root.stampMode
                 Slider {
                     id: penWidthSlider
                     from: 1
                     to: 50
                     value: 5
                 }
                 Label {
                     Layout.fillWidth: true
                     text: "Pen Width"
                 }
             }

         }

         Texture {
             id: drawerTexture
             sourceItem: drawerChoice.checked ? drawer : null
             mappingMode: envMapMode ? Texture.Environment : Texture.UV
         }

     }