AreaOrderer.cpp

// AreaOrderer.cpp
// Copyright (c) 2010, Dan Heeks
// This program is released under the BSD license. See the file COPYING for details.

#include "AreaOrderer.h"
#include "Area.h"

CAreaOrderer* CInnerCurves::area_orderer = NULL;

CInnerCurves::CInnerCurves(CInnerCurves* pOuter, const CCurve* curve)
{
	m_pOuter = pOuter;
	m_curve = curve;
	m_unite_area = NULL;
}

CInnerCurves::~CInnerCurves()
{
	delete m_unite_area;
}

void CInnerCurves::Insert(const CCurve* pcurve)
{
	std::list<CInnerCurves*> outside_of_these;
	std::list<CInnerCurves*> crossing_these;

	// check all inner curves
	for(std::set<CInnerCurves*>::iterator It = m_inner_curves.begin(); It != m_inner_curves.end(); It++)
	{
		CInnerCurves* c = *It;

		switch(GetOverlapType(*pcurve, *(c->m_curve)))
		{
		case eOutside:
			outside_of_these.push_back(c);
			break;

		case eInside:
			// insert in this inner curve
			c->Insert(pcurve);
			return;

		case eSiblings:
			break;

		case eCrossing:
			crossing_these.push_back(c);
			break;
		}
	}

	// add as a new inner
	CInnerCurves* new_item = new CInnerCurves(this, pcurve);
	this->m_inner_curves.insert(new_item);

	for(std::list<CInnerCurves*>::iterator It = outside_of_these.begin(); It != outside_of_these.end(); It++)
	{
		// move items
		CInnerCurves* c = *It;
		c->m_pOuter = new_item;
		new_item->m_inner_curves.insert(c);
		this->m_inner_curves.erase(c);
	}

	for(std::list<CInnerCurves*>::iterator It = crossing_these.begin(); It != crossing_these.end(); It++)
	{
		// unite these
		CInnerCurves* c = *It;
		new_item->Unite(c);
		this->m_inner_curves.erase(c);
	}
}

void CInnerCurves::GetArea(CArea &area, bool outside, bool use_curve)const
{
	if(use_curve && m_curve)
	{
		area.m_curves.push_back(*m_curve);
		outside = !outside;
	}

	std::list<const CInnerCurves*> do_after;

	for(std::set<CInnerCurves*>::const_iterator It = m_inner_curves.begin(); It != m_inner_curves.end(); It++)
	{
		const CInnerCurves* c = *It;
		area.m_curves.push_back(*c->m_curve);
		if(!outside)area.m_curves.back().Reverse();

		if(outside)c->GetArea(area, !outside, false);
		else do_after.push_back(c);
	}

	for(std::list<const CInnerCurves*>::iterator It = do_after.begin(); It != do_after.end(); It++)
	{
		const CInnerCurves* c = *It;
		c->GetArea(area, !outside, false);
	}
}

void CInnerCurves::Unite(const CInnerCurves* c)
{
	// unite all the curves in c, with this one
	CArea* new_area = new CArea();
	new_area->m_curves.push_back(*m_curve);
	delete m_unite_area;
	m_unite_area = new_area;

	CArea a2;
	c->GetArea(a2);

	m_unite_area->Union(a2);
	m_unite_area->Reorder();
	for(std::list<CCurve>::iterator It = m_unite_area->m_curves.begin(); It != m_unite_area->m_curves.end(); It++)
	{
		CCurve &curve = *It;
		if(It == m_unite_area->m_curves.begin())
			m_curve = &curve;
		else
		{
			if(curve.IsClockwise())curve.Reverse();
			Insert(&curve);
		}
	}
}

CAreaOrderer::CAreaOrderer()
{
	m_top_level = new CInnerCurves(NULL, NULL);
}

void CAreaOrderer::Insert(CCurve* pcurve)
{
	CInnerCurves::area_orderer = this;

	// make them all anti-clockwise as they come in
	if(pcurve->IsClockwise())pcurve->Reverse();

	m_top_level->Insert(pcurve);
}

CArea CAreaOrderer::ResultArea()const
{
	CArea a;

	if(m_top_level)
	{
		m_top_level->GetArea(a);
	}

	return a;
}