集成OSG

一，新建一个 QOsgWidget 类，继承自osgQOpenGLWidget

#ifndef QOSGWIDGET_H
#define QOSGWIDGET_H

#include <QObject>
#include <osgViewer/Viewer>
#include <osgQOpenGL/osgQOpenGLWidget>
class QOsgWidget: public osgQOpenGLWidget
{
    public:
        explicit QOsgWidget(QWidget *parent = nullptr);
        QSize sizeHint() const;

        void InitQOsgWidget();

};

#endif // QOSGWIDGET_H

#include "qosgwidget.h"
#include <QDebug>
QOsgWidget::QOsgWidget(QWidget *parent):osgQOpenGLWidget(parent)
{
    //多重采样
    QSurfaceFormat surfaceFormat;
    surfaceFormat.setSamples(6);
    setFormat(surfaceFormat);
}

QSize QOsgWidget::sizeHint() const
{
    return QSize(this->width(),this->height());
}

二，UI中创建一个QWidget 并提升为QOsgWidget

三，主窗初始化这个QOsgWidget。 这里以一个 网格 节点为例。

#ifndef WIDGET_H
#define WIDGET_H

#include <osg/Node>
#include <QWidget>
#include "qosgwidget.h"

QT_BEGIN_NAMESPACE
namespace Ui {
class Widget;
}
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget(QWidget *parent = nullptr);
    ~Widget();

private:
    Ui::Widget *ui;

    void InitQOsgWidget();

    osg::ref_ptr<osg::Group> _Root = nullptr;
    osg::ref_ptr<osgViewer::Viewer> _Viewer = nullptr;
};
#endif // WIDGET_H

#include "widget.h"
#include "ui_widget.h"

#include <osgGA/TrackballManipulator>
#include <osgUtil/Optimizer>
#include <osgGA/GUIEventHandler>
#include <osgViewer/ViewerEventHandlers>

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);

    connect(ui->widget, &osgQOpenGLWidget::initialized, this, &Widget::InitQOsgWidget);
}

Widget::~Widget()
{
    delete ui;
}

void Widget::InitQOsgWidget()
{
    _Root = new osg::Group();
    QSize size = ui->widget->size();

    osg::ref_ptr<osgGA::TrackballManipulator> trackball = new osgGA::TrackballManipulator;
    trackball->setAllowThrow(false);
    trackball->setAutoComputeHomePosition(true);
    trackball->setThreadSafeRefUnref(true);

    osgUtil::Optimizer optimizer;
    optimizer.optimize(_Root.get());
    _Viewer = ui->widget->getOsgViewer();

    _Viewer->addEventHandler(new osgViewer::StatsHandler);
    _Viewer->getCamera()->setClearColor(osg::Vec4(0.2, 0.2, 0.2, 1));
    _Viewer->getCamera()->setProjectionMatrixAsPerspective(30.0f, static_cast<double>(size.width())/static_cast<double>(size.height()), 1.0f, 10000.0f );
    _Viewer->setCameraManipulator(trackball);
    _Viewer->setRunMaxFrameRate(60);


    osg::ref_ptr<osg::Geode> grid = new osg::Geode;
    osg::Geometry* geom = new osg::Geometry;
    grid->addChild(geom);

    osg::Vec3Array* vertex = new osg::Vec3Array;
    geom->setVertexArray(vertex);
    //沿xy平面画线，间隔500米，从-10000，画到100000
    for (int i = -10; i <= 10; i += 1)
    {
        vertex->push_back(osg::Vec3(i, -10, 0));
        vertex->push_back(osg::Vec3(i, 10, 0));
        vertex->push_back(osg::Vec3(-10, i, 0));
        vertex->push_back(osg::Vec3(10, i, 0));
    }
    geom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::LINES, 0, vertex->size()));
    osg::Vec4Array* color = new osg::Vec4Array();
    color->push_back(osg::Vec4(0.7, 0.7, 0.7, 1.0));
    geom->setColorArray(color, osg::Array::BIND_OVERALL);
    geom->getOrCreateStateSet()->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
    _Root->addChild(grid);

    _Viewer->setSceneData(_Root.get());
}

四，效果