Add documentation for simplecustommaterial example

Task-number: QTBUG-60287
Change-Id: Id167ddd190b7aa5468bc6590c9f9f4fea234430b
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

examples/qt3d/simplecustommaterial/SimpleMaterial.qml

@@ -54,6 +54,7 @@ import Qt3D.Render 2.0
 Material {
     id: root
 
+    //! [0]
     property color maincolor: Qt.rgba(0.0, 0.0, 0.0, 1.0)
 
     parameters: [
@@ -63,18 +64,24 @@ Material {
         }
     ]
 
+    //! [0]
+
     effect: Effect {
 
+        //! [1]
         property string vertex: "qrc:/shaders/gl3/simpleColor.vert"
         property string fragment: "qrc:/shaders/gl3/simpleColor.frag"
         property string vertexES: "qrc:/shaders/es2/simpleColor.vert"
         property string fragmentES: "qrc:/shaders/es2/simpleColor.frag"
+        //! [1]
 
         FilterKey {
             id: forward
             name: "renderingStyle"
             value: "forward"
         }
+
+        //! [2]
         ShaderProgram {
             id: gl3Shader
             vertexShaderCode: loadSource(parent.vertex)
@@ -85,7 +92,10 @@ Material {
             vertexShaderCode: loadSource(parent.vertexES)
             fragmentShaderCode: loadSource(parent.fragmentES)
         }
+        //! [2]
+
         techniques: [
+            //! [3]
             // OpenGL 3.1
             Technique {
                 filterKeys: [forward]
@@ -99,6 +109,7 @@ Material {
                     shaderProgram: gl3Shader
                 }
             },
+            //! [3]
             // OpenGL 2.0
             Technique {
                 filterKeys: [forward]

examples/qt3d/simplecustommaterial/doc/src/simplecustommaterial.qdoc

@@ -0,0 +1,86 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+    \example simplecustommaterial
+    \title Qt 3D: Simple custom material QML Example
+    \ingroup qt3d-examples-qml
+    \brief Demonstrates creating a custom material in Qt3D
+
+    \image simple-custom-material.jpg
+
+    \e This example demonstrates creating a simple custom material.
+
+    \include examples-run.qdocinc
+
+    \section1 Specifying the scene
+
+    The example uses \l Scene3D to render a scene which will use the custom material.
+    The scene contains a plane model, which uses the custom material.
+
+    \quotefromfile simplecustommaterial/PlaneModel.qml
+    \skipto Entity
+    \printto
+
+    \section1 Specifying the material
+
+    The material is specified in \l{simplecustommaterial/SimpleMaterial.qml}{SimpleMaterial.qml}
+    using \l Material type. First the material specifies parameters,
+    which are mapped to the corresponding uniforms in the shaders so that they can be
+    changed from the qml.
+
+    \snippet simplecustommaterial/SimpleMaterial.qml 0
+
+    Next we specify which shaders are loaded. Separate versions of the shaders are provided
+    for OpenGL ES 2 and OpenGL renderers.
+
+    \snippet simplecustommaterial/SimpleMaterial.qml 1
+
+    In the vertex shader we simply transform the position by the transformation matrices.
+
+    \quotefromfile simplecustommaterial/shaders/gl3/simpleColor.vert
+    \skipto void main()
+    \printto
+
+    In the fragment shader we simply set the fragment color to be the maincolor specified
+    in the material.
+
+    \quotefromfile simplecustommaterial/shaders/gl3/simpleColor.frag
+    \skipto uniform vec3 maincolor;
+    \printuntil ;
+    \skipto void main()
+    \printto
+
+    Next, we create \l {ShaderProgram}{ShaderPrograms} from the shaders.
+
+    \snippet simplecustommaterial/SimpleMaterial.qml 2
+
+    Finally the shader programs are used in the Techniques corresponding to a specific
+    Api profile.
+
+    \snippet simplecustommaterial/SimpleMaterial.qml 3
+*/

src/doc/qt3d.qdocconf

@@ -80,7 +80,8 @@ imagedirs   += images \
                ../../examples/qt3d/basicshapes-cpp/doc/images \
                ../../examples/qt3d/planets-qml/doc/images \
                ../../examples/qt3d/wireframe/doc/images \
-               ../../examples/qt3d/audio-visualizer-qml/doc/images
+               ../../examples/qt3d/audio-visualizer-qml/doc/images \
+               ../../examples/qt3d/simplecustommaterial/doc/images
 
 Cpp.ignoretokens     += QT3DINPUTSHARED_EXPORT \
                         QT3DCORESHARED_EXPORT \