| /* | |
| Copyright 2008 Intel Corporation | |
| Use, modification and distribution are subject to the Boost Software License, | |
| Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at | |
| http://www.boost.org/LICENSE_1_0.txt). | |
| */ | |
| #ifndef BOOST_POLYGON_RECTANGLE_FORMATION_HPP | |
| #define BOOST_POLYGON_RECTANGLE_FORMATION_HPP | |
| namespace boost { namespace polygon{ | |
| namespace rectangle_formation { | |
| template <class T> | |
| class ScanLineToRects { | |
| public: | |
| typedef T rectangle_type; | |
| typedef typename rectangle_traits<T>::coordinate_type coordinate_type; | |
| typedef rectangle_data<coordinate_type> scan_rect_type; | |
| private: | |
| typedef std::set<scan_rect_type, less_rectangle_concept<scan_rect_type, scan_rect_type> > ScanData; | |
| ScanData scanData_; | |
| bool haveCurrentRect_; | |
| scan_rect_type currentRect_; | |
| orientation_2d orient_; | |
| typename rectangle_traits<T>::coordinate_type currentCoordinate_; | |
| public: | |
| inline ScanLineToRects() : scanData_(), haveCurrentRect_(), currentRect_(), orient_(), currentCoordinate_() {} | |
| inline ScanLineToRects(orientation_2d orient, rectangle_type model) : | |
| scanData_(orientation_2d(orient.to_int() ? VERTICAL : HORIZONTAL)), | |
| haveCurrentRect_(false), currentRect_(), orient_(orient), currentCoordinate_() { | |
| assign(currentRect_, model); | |
| currentCoordinate_ = (std::numeric_limits<coordinate_type>::max)(); | |
| } | |
| template <typename CT> | |
| inline ScanLineToRects& processEdge(CT& rectangles, const interval_data<coordinate_type>& edge); | |
| inline ScanLineToRects& nextMajorCoordinate(coordinate_type currentCoordinate) { | |
| if(haveCurrentRect_) { | |
| scanData_.insert(scanData_.end(), currentRect_); | |
| haveCurrentRect_ = false; | |
| } | |
| currentCoordinate_ = currentCoordinate; | |
| return *this; | |
| } | |
| }; | |
| template <class CT, class ST, class rectangle_type, typename interval_type, typename coordinate_type> inline CT& | |
| processEdge_(CT& rectangles, ST& scanData, const interval_type& edge, | |
| bool& haveCurrentRect, rectangle_type& currentRect, coordinate_type currentCoordinate, orientation_2d orient) | |
| { | |
| typedef typename CT::value_type result_type; | |
| bool edgeProcessed = false; | |
| if(!scanData.empty()) { | |
| //process all rectangles in the scanData that touch the edge | |
| typename ST::iterator dataIter = scanData.lower_bound(rectangle_type(edge, edge)); | |
| //decrement beginIter until its low is less than edge's low | |
| while((dataIter == scanData.end() || (*dataIter).get(orient).get(LOW) > edge.get(LOW)) && | |
| dataIter != scanData.begin()) | |
| { | |
| --dataIter; | |
| } | |
| //process each rectangle until the low end of the rectangle | |
| //is greater than the high end of the edge | |
| while(dataIter != scanData.end() && | |
| (*dataIter).get(orient).get(LOW) <= edge.get(HIGH)) | |
| { | |
| const rectangle_type& rect = *dataIter; | |
| //if the rectangle data intersects the edge at all | |
| if(rect.get(orient).get(HIGH) >= edge.get(LOW)) { | |
| if(contains(rect.get(orient), edge, true)) { | |
| //this is a closing edge | |
| //we need to write out the intersecting rectangle and | |
| //insert between 0 and 2 rectangles into the scanData | |
| //write out rectangle | |
| rectangle_type tmpRect = rect; | |
| if(rect.get(orient.get_perpendicular()).get(LOW) < currentCoordinate) { | |
| //set the high coordinate perpedicular to slicing orientation | |
| //to the current coordinate of the scan event | |
| tmpRect.set(orient.get_perpendicular().get_direction(HIGH), | |
| currentCoordinate); | |
| result_type result; | |
| assign(result, tmpRect); | |
| rectangles.insert(rectangles.end(), result); | |
| } | |
| //erase the rectangle from the scan data | |
| typename ST::iterator nextIter = dataIter; | |
| ++nextIter; | |
| scanData.erase(dataIter); | |
| if(tmpRect.get(orient).get(LOW) < edge.get(LOW)) { | |
| //insert a rectangle for the overhang of the bottom | |
| //of the rectangle back into scan data | |
| rectangle_type lowRect(tmpRect); | |
| lowRect.set(orient.get_perpendicular(), interval_data<coordinate_type>(currentCoordinate, | |
| currentCoordinate)); | |
| lowRect.set(orient.get_direction(HIGH), edge.get(LOW)); | |
| scanData.insert(nextIter, lowRect); | |
| } | |
| if(tmpRect.get(orient).get(HIGH) > edge.get(HIGH)) { | |
| //insert a rectangle for the overhang of the top | |
| //of the rectangle back into scan data | |
| rectangle_type highRect(tmpRect); | |
| highRect.set(orient.get_perpendicular(), interval_data<coordinate_type>(currentCoordinate, | |
| currentCoordinate)); | |
| highRect.set(orient.get_direction(LOW), edge.get(HIGH)); | |
| scanData.insert(nextIter, highRect); | |
| } | |
| //we are done with this edge | |
| edgeProcessed = true; | |
| break; | |
| } else { | |
| //it must be an opening edge | |
| //assert that rect does not overlap the edge but only touches | |
| //write out rectangle | |
| rectangle_type tmpRect = rect; | |
| //set the high coordinate perpedicular to slicing orientation | |
| //to the current coordinate of the scan event | |
| if(tmpRect.get(orient.get_perpendicular().get_direction(LOW)) < currentCoordinate) { | |
| tmpRect.set(orient.get_perpendicular().get_direction(HIGH), | |
| currentCoordinate); | |
| result_type result; | |
| assign(result, tmpRect); | |
| rectangles.insert(rectangles.end(), result); | |
| } | |
| //erase the rectangle from the scan data | |
| typename ST::iterator nextIter = dataIter; | |
| ++nextIter; | |
| scanData.erase(dataIter); | |
| dataIter = nextIter; | |
| if(haveCurrentRect) { | |
| if(currentRect.get(orient).get(HIGH) >= edge.get(LOW)){ | |
| if(!edgeProcessed && currentRect.get(orient.get_direction(HIGH)) > edge.get(LOW)){ | |
| rectangle_type tmpRect2(currentRect); | |
| tmpRect2.set(orient.get_direction(HIGH), edge.get(LOW)); | |
| scanData.insert(nextIter, tmpRect2); | |
| if(currentRect.get(orient.get_direction(HIGH)) > edge.get(HIGH)) { | |
| currentRect.set(orient, interval_data<coordinate_type>(edge.get(HIGH), currentRect.get(orient.get_direction(HIGH)))); | |
| } else { | |
| haveCurrentRect = false; | |
| } | |
| } else { | |
| //extend the top of current rect | |
| currentRect.set(orient.get_direction(HIGH), | |
| (std::max)(edge.get(HIGH), | |
| tmpRect.get(orient.get_direction(HIGH)))); | |
| } | |
| } else { | |
| //insert current rect into the scanData | |
| scanData.insert(nextIter, currentRect); | |
| //create a new current rect | |
| currentRect.set(orient.get_perpendicular(), interval_data<coordinate_type>(currentCoordinate, | |
| currentCoordinate)); | |
| currentRect.set(orient, interval_data<coordinate_type>((std::min)(tmpRect.get(orient).get(LOW), | |
| edge.get(LOW)), | |
| (std::max)(tmpRect.get(orient).get(HIGH), | |
| edge.get(HIGH)))); | |
| } | |
| } else { | |
| haveCurrentRect = true; | |
| currentRect.set(orient.get_perpendicular(), interval_data<coordinate_type>(currentCoordinate, | |
| currentCoordinate)); | |
| currentRect.set(orient, interval_data<coordinate_type>((std::min)(tmpRect.get(orient).get(LOW), | |
| edge.get(LOW)), | |
| (std::max)(tmpRect.get(orient).get(HIGH), | |
| edge.get(HIGH)))); | |
| } | |
| //skip to nextIter position | |
| edgeProcessed = true; | |
| continue; | |
| } | |
| //edgeProcessed = true; | |
| } | |
| ++dataIter; | |
| } //end while edge intersects rectangle data | |
| } | |
| if(!edgeProcessed) { | |
| if(haveCurrentRect) { | |
| if(currentRect.get(orient.get_perpendicular().get_direction(HIGH)) | |
| == currentCoordinate && | |
| currentRect.get(orient.get_direction(HIGH)) >= edge.get(LOW)) | |
| { | |
| if(currentRect.get(orient.get_direction(HIGH)) > edge.get(LOW)){ | |
| rectangle_type tmpRect(currentRect); | |
| tmpRect.set(orient.get_direction(HIGH), edge.get(LOW)); | |
| scanData.insert(scanData.end(), tmpRect); | |
| if(currentRect.get(orient.get_direction(HIGH)) > edge.get(HIGH)) { | |
| currentRect.set(orient, | |
| interval_data<coordinate_type>(edge.get(HIGH), | |
| currentRect.get(orient.get_direction(HIGH)))); | |
| return rectangles; | |
| } else { | |
| haveCurrentRect = false; | |
| return rectangles; | |
| } | |
| } | |
| //extend current rect | |
| currentRect.set(orient.get_direction(HIGH), edge.get(HIGH)); | |
| return rectangles; | |
| } | |
| scanData.insert(scanData.end(), currentRect); | |
| haveCurrentRect = false; | |
| } | |
| rectangle_type tmpRect(currentRect); | |
| tmpRect.set(orient.get_perpendicular(), interval_data<coordinate_type>(currentCoordinate, | |
| currentCoordinate)); | |
| tmpRect.set(orient, edge); | |
| scanData.insert(tmpRect); | |
| return rectangles; | |
| } | |
| return rectangles; | |
| } | |
| template <class T> | |
| template <class CT> | |
| inline | |
| ScanLineToRects<T>& ScanLineToRects<T>::processEdge(CT& rectangles, const interval_data<coordinate_type>& edge) | |
| { | |
| processEdge_(rectangles, scanData_, edge, haveCurrentRect_, currentRect_, currentCoordinate_, orient_); | |
| return *this; | |
| } | |
| } //namespace rectangle_formation | |
| template <typename T, typename T2> | |
| struct get_coordinate_type_for_rectangles { | |
| typedef typename polygon_traits<T>::coordinate_type type; | |
| }; | |
| template <typename T> | |
| struct get_coordinate_type_for_rectangles<T, rectangle_concept> { | |
| typedef typename rectangle_traits<T>::coordinate_type type; | |
| }; | |
| template <typename output_container, typename iterator_type, typename rectangle_concept> | |
| void form_rectangles(output_container& output, iterator_type begin, iterator_type end, | |
| orientation_2d orient, rectangle_concept ) { | |
| typedef typename output_container::value_type rectangle_type; | |
| typedef typename get_coordinate_type_for_rectangles<rectangle_type, typename geometry_concept<rectangle_type>::type>::type Unit; | |
| rectangle_data<Unit> model; | |
| Unit prevPos = (std::numeric_limits<Unit>::max)(); | |
| rectangle_formation::ScanLineToRects<rectangle_data<Unit> > scanlineToRects(orient, model); | |
| for(iterator_type itr = begin; | |
| itr != end; ++ itr) { | |
| Unit pos = (*itr).first; | |
| if(pos != prevPos) { | |
| scanlineToRects.nextMajorCoordinate(pos); | |
| prevPos = pos; | |
| } | |
| Unit lowy = (*itr).second.first; | |
| iterator_type tmp_itr = itr; | |
| ++itr; | |
| Unit highy = (*itr).second.first; | |
| scanlineToRects.processEdge(output, interval_data<Unit>(lowy, highy)); | |
| if(abs((*itr).second.second) > 1) itr = tmp_itr; //next edge begins from this vertex | |
| } | |
| } | |
| } | |
| } | |
| #endif | |