custom-mesh-cpp example

Demonstrate how to use the Buffer API to create a custom tetrahedron mesh.

Change-Id: Ie30458c8a6dc3e2d8b1c6aef4a95a57f4cc63de9
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

3 files changed, 265 insertions, 1 deletions

diff --git a/examples/qt3d/custom-mesh-cpp/custom-mesh-cpp.pro b/examples/qt3d/custom-mesh-cpp/custom-mesh-cpp.pro
new file mode 100644
index 000000000..0097f0cf2
--- /dev/null
+++ b/examples/qt3d/custom-mesh-cpp/custom-mesh-cpp.pro
@@ -0,0 +1,8 @@
+!include( ../examples.pri ) {
+    error( "Couldn't find the examples.pri file!" )
+}
+
+QT += 3dcore 3drenderer 3dinput
+
+SOURCES += \
+    main.cpp
diff --git a/examples/qt3d/custom-mesh-cpp/main.cpp b/examples/qt3d/custom-mesh-cpp/main.cpp
new file mode 100644
index 000000000..4d4e58761
--- /dev/null
+++ b/examples/qt3d/custom-mesh-cpp/main.cpp
@@ -0,0 +1,255 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Qt3D module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QGuiApplication>
+
+#include <window.h>
+#include <Qt3DCore/QEntity>
+#include <Qt3DCore/QCamera>
+#include <Qt3DCore/QCameraLens>
+#include <Qt3DCore/QTransform>
+#include <Qt3DCore/QLookAtTransform>
+#include <Qt3DCore/QScaleTransform>
+#include <Qt3DCore/QRotateTransform>
+#include <Qt3DCore/QTranslateTransform>
+#include <Qt3DCore/QAspectEngine>
+
+#include <Qt3DInput/QInputAspect>
+
+#include <Qt3DRenderer/QRenderAspect>
+#include <Qt3DRenderer/QFrameGraph>
+#include <Qt3DRenderer/QForwardRenderer>
+#include <Qt3DRenderer/QPhongMaterial>
+
+#include <Qt3DRenderer/QGeometryRenderer>
+#include <Qt3DRenderer/QGeometry>
+#include <Qt3DRenderer/QAttribute>
+#include <Qt3DRenderer/QBuffer>
+#include <Qt3DRenderer/QMeshData>
+
+#include <QPropertyAnimation>
+
+int main(int argc, char* argv[])
+{
+    QGuiApplication app(argc, argv);
+    Window view;
+
+    Qt3D::QAspectEngine engine;
+    engine.registerAspect(new Qt3D::QRenderAspect());
+    Qt3D::QInputAspect *input = new Qt3D::QInputAspect;
+    engine.registerAspect(input);
+    engine.initialize();
+    QVariantMap data;
+    data.insert(QStringLiteral("surface"), QVariant::fromValue(static_cast<QSurface *>(&view)));
+    data.insert(QStringLiteral("eventSource"), QVariant::fromValue(&view));
+    engine.setData(data);
+
+    // Root entity
+    Qt3D::QEntity *rootEntity = new Qt3D::QEntity();
+
+    // Camera
+    Qt3D::QCamera *cameraEntity = new Qt3D::QCamera(rootEntity);
+
+    cameraEntity->lens()->setPerspectiveProjection(45.0f, 16.0f/9.0f, 0.1f, 1000.0f);
+    cameraEntity->setPosition(QVector3D(0, 0, -40.0f));
+    cameraEntity->setUpVector(QVector3D(0, 1, 0));
+    cameraEntity->setViewCenter(QVector3D(0, 0, 0));
+    input->setCamera(cameraEntity);
+
+    // FrameGraph
+    Qt3D::QFrameGraph *frameGraph = new Qt3D::QFrameGraph();
+    Qt3D::QForwardRenderer *forwardRenderer = new Qt3D::QForwardRenderer();
+    forwardRenderer->setClearColor(QColor::fromRgbF(0.0, 0.5, 1.0, 1.0));
+    forwardRenderer->setCamera(cameraEntity);
+    frameGraph->setActiveFrameGraph(forwardRenderer);
+
+    // Material
+    Qt3D::QMaterial *material = new Qt3D::QPhongMaterial(rootEntity);
+
+    // Torus
+    Qt3D::QEntity *customMeshEntity = new Qt3D::QEntity(rootEntity);
+
+    // Transform
+    Qt3D::QTransform *transform = new Qt3D::QTransform;
+    Qt3D::QScaleTransform *scaleTransform = new Qt3D::QScaleTransform;
+    scaleTransform->setScale3D(QVector3D(1.5, 1, 0.5));
+    Qt3D::QRotateTransform *rotateTransform = new Qt3D::QRotateTransform;
+    rotateTransform->setAxis(QVector3D(1, 0, 0));
+    rotateTransform->setAngleDeg(45);
+    transform->addTransform(scaleTransform);
+    transform->addTransform(rotateTransform);
+
+    // Custom Mesh (TetraHedron)
+    Qt3D::QGeometryRenderer *customMeshRenderer = new Qt3D::QGeometryRenderer;
+    Qt3D::QGeometry *customGeometry = new Qt3D::QGeometry(customMeshRenderer);
+
+    Qt3D::QBuffer *vertexDataBuffer = new Qt3D::QBuffer(Qt3D::QBuffer::VertexBuffer, customGeometry);
+    Qt3D::QBuffer *indexDataBuffer = new Qt3D::QBuffer(Qt3D::QBuffer::IndexBuffer, customGeometry);
+
+    // vec3 for position
+    // vec3 for colors
+    // vec3 for normals
+
+    /*          2
+               /|\
+              / | \
+             / /3\ \
+             0/___\ 1
+    */
+
+    // 4 distinct vertices
+    QByteArray vertexBufferData;
+    vertexBufferData.resize(4 * (3 + 3 + 3) * sizeof(float));
+
+    // Vertices
+    QVector3D v0(-1.0f, 0.0f, -1.0f);
+    QVector3D v1(1.0f, 0.0f, -1.0f);
+    QVector3D v2(0.0f, 1.0f, 0.0f);
+    QVector3D v3(0.0f, 0.0f, 1.0f);
+
+    // Faces Normals
+    QVector3D n023 = QVector3D::normal(v0, v2, v3);
+    QVector3D n012 = QVector3D::normal(v0, v1, v2);
+    QVector3D n310 = QVector3D::normal(v3, v1, v0);
+    QVector3D n132 = QVector3D::normal(v1, v3, v2);
+
+    // Vector Normals
+    QVector3D n0 = QVector3D(n023 + n012 + n310).normalized();
+    QVector3D n1 = QVector3D(n132 + n012 + n310).normalized();
+    QVector3D n2 = QVector3D(n132 + n012 + n023).normalized();
+    QVector3D n3 = QVector3D(n132 + n310 + n023).normalized();
+
+    // Colors
+    QVector3D red(1.0f, 0.0f, 0.0f);
+    QVector3D green(0.0f, 1.0f, 0.0f);
+    QVector3D blue(0.0f, 0.0f, 1.0f);
+    QVector3D white(1.0f, 1.0f, 1.0f);
+
+    QVector<QVector3D> vertices = QVector<QVector3D>()
+            << v0 << n0 << red
+            << v1 << n1 << blue
+            << v2 << n2 << green
+            << v3 << n3 << white;
+
+    float *rawVertexArray = reinterpret_cast<float *>(vertexBufferData.data());
+    int idx = 0;
+
+    Q_FOREACH (const QVector3D &v, vertices) {
+        rawVertexArray[idx++] = v.x();
+        rawVertexArray[idx++] = v.y();
+        rawVertexArray[idx++] = v.z();
+    }
+
+    // Indices (12)
+    QByteArray indexBufferData;
+    indexBufferData.resize(4 * 3 * sizeof(ushort));
+    ushort *rawIndexArray = reinterpret_cast<ushort *>(indexBufferData.data());
+
+    // Front
+    rawIndexArray[0] = 0;
+    rawIndexArray[1] = 1;
+    rawIndexArray[2] = 2;
+    // Bottom
+    rawIndexArray[3] = 3;
+    rawIndexArray[4] = 1;
+    rawIndexArray[5] = 0;
+    // Left
+    rawIndexArray[6] = 0;
+    rawIndexArray[7] = 2;
+    rawIndexArray[8] = 3;
+    // Right
+    rawIndexArray[9] = 1;
+    rawIndexArray[10] = 3;
+    rawIndexArray[11] = 2;
+
+    vertexDataBuffer->setData(vertexBufferData);
+    indexDataBuffer->setData(indexBufferData);
+
+    // Attributes
+    Qt3D::QAttribute *positionAttribute = new Qt3D::QAttribute();
+    positionAttribute->setAttributeType(Qt3D::QAttribute::VertexAttribute);
+    positionAttribute->setBuffer(vertexDataBuffer);
+    positionAttribute->setType(GL_FLOAT_VEC3);
+    positionAttribute->setByteOffset(0);
+    positionAttribute->setByteStride(9 * sizeof(float));
+    positionAttribute->setCount(4);
+    positionAttribute->setName(Qt3D::QMeshData::defaultPositionAttributeName());
+
+    Qt3D::QAttribute *normalAttribute = new Qt3D::QAttribute();
+    normalAttribute->setAttributeType(Qt3D::QAttribute::VertexAttribute);
+    normalAttribute->setBuffer(vertexDataBuffer);
+    normalAttribute->setType(GL_FLOAT_VEC3);
+    normalAttribute->setByteOffset(3 * sizeof(float));
+    normalAttribute->setByteStride(9 * sizeof(float));
+    normalAttribute->setCount(4);
+    normalAttribute->setName(Qt3D::QMeshData::defaultNormalAttributeName());
+
+    Qt3D::QAttribute *colorAttribute = new Qt3D::QAttribute();
+    colorAttribute->setAttributeType(Qt3D::QAttribute::VertexAttribute);
+    colorAttribute->setBuffer(vertexDataBuffer);
+    colorAttribute->setType(GL_FLOAT_VEC3);
+    colorAttribute->setByteOffset(6 * sizeof(float));
+    colorAttribute->setByteStride(9 * sizeof(float));
+    colorAttribute->setCount(4);
+    colorAttribute->setName(Qt3D::QMeshData::defaultColorAttributeName());
+
+    Qt3D::QAttribute *indexAttribute = new Qt3D::QAttribute();
+    indexAttribute->setAttributeType(Qt3D::QAttribute::IndexAttribute);
+    indexAttribute->setBuffer(indexDataBuffer);
+    colorAttribute->setType(GL_UNSIGNED_SHORT);
+    colorAttribute->setByteOffset(0);
+    colorAttribute->setByteStride(0);
+    colorAttribute->setCount(12);
+
+    customGeometry->addAttribute(positionAttribute);
+    customGeometry->addAttribute(normalAttribute);
+    customGeometry->addAttribute(colorAttribute);
+    customGeometry->addAttribute(indexAttribute);
+
+    customMeshRenderer->setGeometry(customGeometry);
+
+    customMeshEntity->addComponent(customMeshRenderer);
+    customMeshEntity->addComponent(transform);
+    customMeshEntity->addComponent(material);
+
+
+    rootEntity->addComponent(frameGraph);
+
+    engine.setRootEntity(rootEntity);
+    view.show();
+
+    return app.exec();
+}
diff --git a/examples/qt3d/qt3d.pro b/examples/qt3d/qt3d.pro
index dc1b8f93e..856836e86 100644
--- a/examples/qt3d/qt3d.pro
+++ b/examples/qt3d/qt3d.pro
@@ -37,7 +37,8 @@ SUBDIRS += \
     transparency-qml-scene3d \
     scene3d-loader \
     clip-planes-qml \
-    mouseinput-qml
+    mouseinput-qml \
+    custom-mesh-cpp
 
 # TODO Port the old examples to new APIs
 #SUBDIRS += qt3d