/*
\brief 二分查找法，求多边形上方向是u的极点，设凸多边形是逆时针顺序的。
*/
int ExtremePoint_BinarySearch( const Point2D* p, int n, const Vector2D& u)
{
int a = 0, b = n, m;
int upA = Direction(p[1] - p[0],u) , upM;
if( upA<=0 && !IsAbove(p[n-1],p[0],u) )
return 0;
while(true)
{
m = (a + b) / 2;
upM = Direction(p[(m+1)%n] - p[m],u);
if( upM<=0 && !IsAbove(p[m-1],p[m],u) )
return m;
if( upA>0 )
{
if( upM<0 )
{ //选择[a,m]
b = m;
}
else if( IsAbove(p[a],p[m],u) )
{ //选择[a,m]
b = m;
}
else
{ //选择[m,b]
a = m;
upA = upM;
}
}
else
{
if( upM>0 )
{ //选择[m,b]
a = m;
upA = upM;
}
else if( IsBelow(p[a],p[m],u) )
{ //选择[a,m]
b = m;
}
else
{ //选择[m,b]
a = m;
upA = upM;
}
}
}
return 0;
}
void BOCTX::InsMainList(SEGM2 * s)
{
SEGM_LIST::iterator segm = m_S.begin();
while (segm != m_S.end() and IsAbove(*s, *segm))
++segm;
// insert s below segm
m_S.insert(segm, *s);
} // BOCTX::InsMainList
bool CglList::MousePress(int x, int y, int button)
{
if (button != SDL_BUTTON_LEFT || !IsAbove(x, y))
return false;
activeMousePress = true;
MouseUpdate(x, y); // make sure place is up to date
return true;
}
bool ProfileDrawer::MousePress(int x, int y, int button)
{
if (!IsAbove(x, y))
return false;
const float my = CInputReceiver::MouseY(y);
const int selIndex = (int) ((start_y - my) / lineHeight);
// switch the selected Timers showGraph value
if ((selIndex >= 0) && (selIndex < profiler.profile.size())) {
auto pi = profiler.profile.begin();
std::advance(pi, selIndex);
pi->second.showGraph = !pi->second.showGraph;
return true;
}
return false;
}
