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// Copyright (C) 2015 Klaralvdalens Datakonsult AB (KDAB).
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#include <QGuiApplication>
#include <QTimer>
#include <Qt3DCore/QEntity>
#include <Qt3DRender/QCamera>
#include <Qt3DRender/QCameraLens>
#include <Qt3DCore/QTransform>
#include <Qt3DCore/QAspectEngine>
#include <Qt3DCore/QGeometry>
#include <Qt3DCore/QAttribute>
#include <Qt3DCore/QBuffer>
#include <Qt3DInput/QInputAspect>
#include <Qt3DRender/QRenderStateSet>
#include <Qt3DRender/QRenderAspect>
#include <Qt3DExtras/QForwardRenderer>
#include <Qt3DExtras/QPerVertexColorMaterial>
#include <Qt3DRender/QGeometryRenderer>
#include <QPropertyAnimation>
#include <Qt3DExtras/qt3dwindow.h>
#include <Qt3DExtras/qfirstpersoncameracontroller.h>
#include <qmath.h>
QByteArray vertexBufferData;
Qt3DCore::QBuffer *vertexDataBuffer;
class TimerObject: public QObject {
Q_OBJECT
public:
TimerObject(QObject *parent = 0): QObject(parent) {
}
~TimerObject() {
}
private slots:
void timeout();
private:
float angle = 0;
};
int main(int argc, char* argv[])
{
QGuiApplication app(argc, argv);
Qt3DExtras::Qt3DWindow view;
view.defaultFrameGraph()->setClearColor(QColor::fromRgbF(0.0, 0.5, 1.0, 1.0));
// Root entity
Qt3DCore::QEntity *rootEntity = new Qt3DCore::QEntity();
// Camera
Qt3DRender::QCamera *cameraEntity = view.camera();
cameraEntity->lens()->setPerspectiveProjection(45.0f, 16.0f/9.0f, 0.1f, 1000.0f);
cameraEntity->setPosition(QVector3D(50.0f, 20.0f, 40.0f));
cameraEntity->setUpVector(QVector3D(0, 1, 0));
cameraEntity->setViewCenter(QVector3D(0, 0, 0));
// For camera controls
Qt3DExtras::QFirstPersonCameraController *camController = new Qt3DExtras::QFirstPersonCameraController(rootEntity);
camController->setCamera(cameraEntity);
// Material
Qt3DRender::QMaterial *material = new Qt3DExtras::QPerVertexColorMaterial(rootEntity);
// Torus
Qt3DCore::QEntity *customMeshEntity = new Qt3DCore::QEntity(rootEntity);
// Transform
Qt3DCore::QTransform *transform = new Qt3DCore::QTransform;
transform->setScale(20.0f);
// Custom Mesh (TetraHedron)
Qt3DRender::QGeometryRenderer *customMeshRenderer = new Qt3DRender::QGeometryRenderer;
Qt3DCore::QGeometry *customGeometry = new Qt3DCore::QGeometry(customMeshRenderer);
vertexDataBuffer = new Qt3DCore::QBuffer(customGeometry);
Qt3DCore::QBuffer *indexDataBuffer = new Qt3DCore::QBuffer(customGeometry);
// vec3 for position
// vec3 for colors
// vec3 for normals
/* 2
/|\
/ | \
/ /3\ \
0/___\ 1
*/
// 4 distinct vertices
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);
const QList<QVector3D> vertices = { v0, n0, red,
v1, n1, blue,
v2, n2, green,
v3, n3, white };
float *rawVertexArray = reinterpret_cast<float *>(vertexBufferData.data());
int idx = 0;
for (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
Qt3DCore::QAttribute *positionAttribute = new Qt3DCore::QAttribute();
positionAttribute->setAttributeType(Qt3DCore::QAttribute::VertexAttribute);
positionAttribute->setBuffer(vertexDataBuffer);
positionAttribute->setVertexSize(3);
positionAttribute->setByteOffset(0);
positionAttribute->setByteStride(9 * sizeof(float));
positionAttribute->setCount(4);
positionAttribute->setName(Qt3DCore::QAttribute::defaultPositionAttributeName());
Qt3DCore::QAttribute *normalAttribute = new Qt3DCore::QAttribute();
normalAttribute->setAttributeType(Qt3DCore::QAttribute::VertexAttribute);
normalAttribute->setBuffer(vertexDataBuffer);
normalAttribute->setVertexSize(3);
normalAttribute->setByteOffset(3 * sizeof(float));
normalAttribute->setByteStride(9 * sizeof(float));
normalAttribute->setCount(4);
normalAttribute->setName(Qt3DCore::QAttribute::defaultNormalAttributeName());
Qt3DCore::QAttribute *colorAttribute = new Qt3DCore::QAttribute();
colorAttribute->setAttributeType(Qt3DCore::QAttribute::VertexAttribute);
colorAttribute->setBuffer(vertexDataBuffer);
colorAttribute->setVertexSize(3);
colorAttribute->setByteOffset(6 * sizeof(float));
colorAttribute->setByteStride(9 * sizeof(float));
colorAttribute->setCount(4);
colorAttribute->setName(Qt3DCore::QAttribute::defaultColorAttributeName());
Qt3DCore::QAttribute *indexAttribute = new Qt3DCore::QAttribute();
indexAttribute->setAttributeType(Qt3DCore::QAttribute::IndexAttribute);
indexAttribute->setBuffer(indexDataBuffer);
indexAttribute->setVertexBaseType(Qt3DCore::QAttribute::UnsignedShort);
indexAttribute->setVertexSize(1);
indexAttribute->setByteOffset(0);
indexAttribute->setByteStride(0);
indexAttribute->setCount(12);
customGeometry->addAttribute(positionAttribute);
customGeometry->addAttribute(normalAttribute);
customGeometry->addAttribute(colorAttribute);
customGeometry->addAttribute(indexAttribute);
customMeshRenderer->setInstanceCount(1);
customMeshRenderer->setIndexOffset(0);
customMeshRenderer->setFirstInstance(0);
customMeshRenderer->setPrimitiveType(Qt3DRender::QGeometryRenderer::Triangles);
customMeshRenderer->setGeometry(customGeometry);
// 4 faces of 3 points
customMeshRenderer->setVertexCount(12);
customMeshEntity->addComponent(customMeshRenderer);
customMeshEntity->addComponent(transform);
customMeshEntity->addComponent(material);
view.setRootEntity(rootEntity);
view.show();
QTimer *timer = new QTimer();
TimerObject *timerObject = new TimerObject();
QObject::connect(timer, SIGNAL(timeout()), timerObject, SLOT(timeout()));
timer->start(10);
return app.exec();
}
void TimerObject::timeout()
{
angle += qDegreesToRadians(0.5f);
QByteArray updateData;
updateData.resize(3*sizeof(float));
// Colors
QVector3D c1(qFabs(qCos(angle + M_PI_4)), qFabs(qSin(angle)), qFabs(qCos(angle)));
QVector3D c2(qFabs(qSin(angle)), qFabs(qCos(angle + M_PI_4)), qFabs(qSin(angle + M_PI_4)));
QVector3D c3(qFabs(qSin(angle + M_PI_4)), qFabs(qSin(angle)), qFabs(qCos(angle)));
const QList<QVector3D> colors = { c1, c2, c3 };
float *rawVertexArray = reinterpret_cast<float *>(updateData.data());
int pos = 6 * sizeof(float); //color offset
for (const QVector3D &v : colors) {
rawVertexArray[0] = v.x();
rawVertexArray[1] = v.y();
rawVertexArray[2] = v.z();
vertexDataBuffer->updateData(pos,updateData);
pos += 9 * sizeof(float); //stride
}
}
#include "main.moc"
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