//计算弧线上距离pt最近的点
PNT XArc::NearPt(PNT pt)
{
float prop = Proportion(pt);
//始点方向
PNT dirBpt = m_StartPt-m_Cen;
dirBpt.Normalize();
//终点方向
PNT dirEpt = m_EndPt-m_Cen;
dirEpt.Normalize();
PNT dir = dirBpt^dirEpt;//dirBpt.CrossProduct(dirEpt);
float angle;
if(dir*m_Normal>0)//始点，终点夹角小于180度
angle = acos(dirBpt*dirEpt);
else
angle = PI*2.0-acos(dirBpt*dirEpt);
float Rotangle = prop*angle;//旋转角度
//最近点
PNT nearpt = m_StartPt;
nearpt.Rotate(m_Cen,m_Normal,Rotangle);
return nearpt;
}
SizerItem grow(wxWindow* window){
return {window, Proportion(1), wxEXPAND};
}
SizerItem center(wxSizer* sizer){
return {sizer, Proportion(0), wxALIGN_CENTER};
}
SizerItem grow(wxSizer* sizer){
return {sizer, Proportion(1), wxEXPAND};
}