//----------------------------------------------
    // Circle
    //----------------------------------------------
    void Circle( Float x, Float y, Float r, const Color& vColor)
    {
        SetColor( vColor );
        glBegin( GL_TRIANGLE_FAN );
            glVertex2f( x, y );
            for( Float i = 0; i <= 2 * PI + 0.1; i += 0.1 )
            {
                glVertex2f( x + sin( i ) * r, y + cos( i ) * r );
            }
        glEnd();
    }