- Qt 6.6
- 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) 2023 The Qt Company Ltd.
     // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

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

     // qmllint disable missing-property
     // Disabling missing-property because the targetMaterial property
     // will either be a PrincipaledMaterial or SpecularGlossyMaterial
     // but the shared properties are not part of the common base class
     ScrollView {
         id: rootView
         required property Material targetMaterial
         required property Model linesModel
         required property Model pointsModel
         property bool specularGlossyMode: false

         ScrollBar.horizontal.policy: ScrollBar.AlwaysOff
         width: availableWidth

         ColumnLayout {
             width: rootView.availableWidth
             MarkdownLabel {
                 text: `# Special Stuff
     The content in this section is as titled \"Special\" because you should really
     only use this stuff for fairly specific reasons.
     ## Lighting Mode
     The lighting mode property defines how the material handles the shading of
     lights. The default mode is *Fragment Lighting* which perform all light shading
     in the fragment shader porsion of the graphics pipeline. In this case all both
     image based lighting as well as any punctual lights are used to shade the material.
     The other case *No Lighting* which ignores all light sources in the scene and
     the material is rendered without shading.  This mode can be useful with models
     that should not be shaded, for example tools (gizmos) inside of a 3D editor.
     `
             }

             ComboBox {
                 id: lightingComboBox
                 textRole: "text"
                 valueRole: "value"
                 implicitContentWidthPolicy: ComboBox.WidestText
                 onActivated: rootView.targetMaterial.lighting = currentValue
                 Component.onCompleted: currentIndex = indexOfValue(rootView.targetMaterial.lighting)
                 model: [
                     { value: PrincipledMaterial.NoLighting, text: "No Lighting"},
                     { value: PrincipledMaterial.FragmentLighting, text: "Fragment Lighting"}
                 ]
             }

             VerticalSectionSeparator {}

             MarkdownLabel {
                 text: `## Non Triangle Primitive Sizes
     Generally if you use the Mesh file format baked by balsam, or the runtime
     loader for loading glTF2 scenes, the geometry primitive will be individual
     triangles, so these properties are not useful. However it is possible to
     create your own mesh geometry where the primitive is instead either Points
     or Lines, and in these cases it is possible to change the size of these
     primitives when rendered. These properties will only have an affect on a
     material when the geometry primitive is set to Line or Point respectively.
     The behavior of these properties will depend on which graphics API the is
     being used, and is possible that they will do nothing at all.`
             }

             Button {
                 text: checked ? "Hide Wireframe Model" : "Show Wireframe Model"
                 checkable: true
                 checked: rootView.linesModel.visible
                 onClicked: {
                     rootView.linesModel.visible = !rootView.linesModel.visible
                 }
             }

             RowLayout {
                 Label {
                     text: "Line Width (" + rootView.targetMaterial.lineWidth.toFixed(2) + ")"
                     Layout.fillWidth: true
                 }
                 Slider {
                     from: 0
                     to: 25
                     value: rootView.targetMaterial.lineWidth
                     onValueChanged: rootView.targetMaterial.lineWidth = value
                 }
             }

             Button {
                 text: checked ? "Hide Point Cloud" : "Show Point Cloud"
                 checkable: true
                 checked: rootView.pointsModel.visible
                 onClicked: {
                     rootView.pointsModel.visible = !rootView.pointsModel.visible
                 }
             }

             RowLayout {
                 Label {
                     text: "Point Size (" + rootView.targetMaterial.pointSize.toFixed(2) + ")"
                     Layout.fillWidth: true
                 }
                 Slider {
                     from: 0
                     to: 25
                     value: rootView.targetMaterial.pointSize
                     onValueChanged: rootView.targetMaterial.pointSize = value
                 }
             }

             ColumnLayout {
                 visible: !rootView.specularGlossyMode
                 VerticalSectionSeparator {}

                 MarkdownLabel {
                     text: `## Specular Overrides
     If you are using this material for Physically Based Rendering (PBR) then
     these properties should not be touched as they are not energy conserving and
     will make materials look less realistic. These exist for adjusting the material
     for artistic or stylistic reasons.`
                 }

                 MarkdownLabel {
                     text: `### Specular Amount
     This Specular Amount property controls the strength of specularity (highlights
     and reflections) of a dielectric material (non-metallic). Normally this should
     be left at 1.0, but can be adjusted to reduce the specularity. Adjusting this
     property will not affect reflections caused by Image Based Lighting.`
                 }
                 RowLayout {
                     Label {
                         text: "Specular Amount  (" + rootView.targetMaterial.specularAmount.toFixed(2) + ")"
                         Layout.fillWidth: true
                     }
                     Slider {
                         from: 0
                         to: 1
                         value: rootView.targetMaterial.specularAmount
                         onValueChanged: rootView.targetMaterial.specularAmount = value
                     }
                 }

                 MarkdownLabel {
                     text: `### Specular Tint
     The Specular Tint property defines how much of the Base Color of the material
     contributes to specular reflections.  This property only has an affect with
     dielectric materials (non-metallic) as metallic material's specular reflections
     are already primarily tinted by the materials base color. This property allows
     the Base Color to also tint the specular reflections for dielectrics as well for
     artistic reasons.`
                 }
                 RowLayout {
                     Label {
                         text: "Specular Tint (" + rootView.targetMaterial.specularTint.toFixed(2) + ")"
                         Layout.fillWidth: true
                     }
                     Slider {
                         from: 0
                         to: 1
                         value: rootView.targetMaterial.specularTint
                         onValueChanged: rootView.targetMaterial.specularTint = value
                     }
                 }

                 MarkdownLabel {
                     text: `### Specular Map
     The Specular Map property defines color (RGB) texture to modulate the amount
     and the color of specularity across the surface of the material. These values
     are multiplied by the Specular Amount property. This property will only have
     an affect if the material is a dielectric (non-metallic).`
                 }

                 TextureSourceControl {
                     defaultClearColor: "black"
                     defaultTexture: "maps/metallic/metallic.jpg"
                     onTargetTextureChanged: {
                         rootView.targetMaterial.specularMap = targetTexture
                     }
                 }

                 MarkdownLabel {
                     text: `### Specular Reflection Map
     The Specular Reflection Map property is for providing a static environment map
     for cheap reflection calculations.  Unlike most properties which take textures
     in PrincipledMaterial, this property requires the source Texture to use the
     EnvironmentMap mapping mode to look correct. In addition this means that the
     source image file should be an equirectangular projection. This is an alternative
     to using Imaged Based Lighting via lightProbes to get static reflections.`
                 }

                 TextureSourceControl {
                     defaultClearColor: "black"
                     defaultTexture: "maps/small_envmap.jpg"
                     envMapMode: true
                     onTargetTextureChanged: {
                         rootView.targetMaterial.specularReflectionMap = targetTexture
                     }
                 }
             }
         }
     }
     // qmllint enable missing-property