Qt Yin Yang Symbol

Source code:

#include <QApplication>

#include <QGraphicsScene>

#include <QGraphicsView>

#include <QGraphicsEllipseItem>

int main(int argc, char *argv[])

{

    QApplication app(argc, argv);

    QGraphicsScene scene;

    scene.setSceneRect( 0.0, 0.0, 200.0, 200.0 );

    QBrush whiteBrush(Qt::white);

    QBrush blackBrush(Qt::black);

    QPen blackPen(Qt::black);

    blackPen.setWidth(3);

    QPen whitePen(Qt::white);

    whitePen.setWidth(3);

    scene.addEllipse(0,0,200,200,blackPen,blackBrush); //big circle

    QPainterPath rightWhiteSemicirclePath;

    rightWhiteSemicirclePath.arcMoveTo(0+3, 0+3, 200-2*3, 200-2*3, 90);

    rightWhiteSemicirclePath.arcTo(0+3, 0+3, 200-2*3, 200-2*3, 90, -180);

    scene.addPath(rightWhiteSemicirclePath,whitePen,whiteBrush);

    QPainterPath leftUpperSmallWhiteSemicirclePath;

    //circle contains in the square shape

    //square length is 100-3=97

    //move the small square x position left (1/4*200)+3=53 pixels

    leftUpperSmallWhiteSemicirclePath.arcMoveTo(50+3, 0+3, 100-3, 100-3, -90);

    leftUpperSmallWhiteSemicirclePath.arcTo(50+3, 0+3, 100-3, 100-3, -90, -180);

    scene.addPath(leftUpperSmallWhiteSemicirclePath,whitePen,whiteBrush);

    QPainterPath rightLowerSmallBlackSemicirclePath;

    rightLowerSmallBlackSemicirclePath.arcMoveTo(53-3, 100+3, 100-3, 100-3, 90);

    rightLowerSmallBlackSemicirclePath.arcTo(53-3, 100+3, 100-3, 100-3, 90, -180);

    scene.addPath(rightLowerSmallBlackSemicirclePath,blackPen,blackBrush);

    scene.addEllipse(100-12.5,  50-12.5, 25, 25, blackPen, blackBrush); //small black upper circle

    scene.addEllipse(100-12.5, 150-12.5, 25, 25, whitePen, whiteBrush); //small white lower circle

    QGraphicsView view( &scene );

    view.setFixedSize(300,300);

    view.setWindowTitle("My Yin Yang Symbol");

    view.show();

    return app.exec();

}

Result: 

 ☯