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["罗恒" <>]

Dear Fernando Cacciola,
     Thank you for your reply.I have defined _SECURE_SCL=0   NDEBUG as       
#define _SECURE_SCL 0   #define NDEBUG in the main.cpp attached in the 
email,but the speed doesnot change at all.What is the reason? Could you give 
me some detail instruction.
   Best regards!



------------------ 原始邮件 ------------------
>From: Fernando Cacciola 
><>
>Reply-To: 
>
>To: 
>
>Subject: Re: [cgal-discuss] How to improve the speed of polygons 
>offsettingin CGAL?
>Date: Mon, 30 Aug 2010 12:28:42 -0300
>
>Hi,
>
>Can you try building CGAL and your code with the following macros defined:
>
>_SECURE_SCL=0
>NDEBUG
>
>That running time you are reporting looks 10 times slower than it should.
>
>Best
>
>-- 
>Fernando Cacciola
>SciSoft Consulting, Founder
>http://www.scisoft-consulting.com
>
>-- 
>You are currently subscribed to cgal-discuss.
>To unsubscribe or access the archives, go to
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>
>
> #include <iostream>
#include <fstream>
#include <boost/shared_ptr.hpp>
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Polygon_2.h>
#include <CGAL/Polygon_with_holes_2.h>
#include <CGAL/create_offset_polygons_from_polygon_with_holes_2.h>

#define _SECURE_SCL 0
#define NDEBUG

typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
typedef K::Point_2 Point_2;
typedef CGAL::Straight_skeleton_2<K> Ss ;
typedef CGAL::Polygon_2<K>    Contour;
typedef boost::shared_ptr<Ss> SsPtr ;
typedef boost::shared_ptr<Contour> PolygonPtr ;
typedef std::vector<PolygonPtr> PolygonPtr_vector ;
typedef CGAL::Polygon_with_holes_2<K> PolygonWithHoles ;
typedef boost::shared_ptr<PolygonWithHoles> PolygonWithHolesPtr ;
typedef std::vector<PolygonWithHolesPtr> PolygonWithHolesPtrVector;

int main(int argc, char **argv)
{
        const char *filename = "F:\\input.txt";
        std::ifstream ifile(filename, std::ios::in);
        if (!ifile)
        {
                std::cout<<"failed to read data from file";
                return 1;
        }

        int iContour,iNode;
        double  x,y;

        PolygonWithHoles temp_pwhs;

        ifile>>iContour;
        std::cout<<"contours:"<<iContour<<"\n";

        std::vector<Contour> temp_poly_list;

        for (int contour=0;contour<iContour;++contour)
        {
                Contour temp_contour;
                temp_contour.clear();

                ifile >> iNode;
                std::cout<<"nodes:"<<iNode<<"\n";               

                for(int i=0;i<iNode;++i)
                {
                        ifile>>x>>y;    
                        temp_contour.push_back(Point_2(x,y));
                        std::cout<<"read a point from file: 
"<<x<<","<<y<<"\n";                         
                }

                if ((temp_contour[0])==(temp_contour[temp_contour.size()-1]))
                {
                
                        temp_contour.erase(temp_contour.vertices_begin());
                        std::cout<<" there are same points in the polygon. \n 
after delete the last the size is"<<temp_contour.size()<<"\n";
                }
                temp_poly_list.push_back(temp_contour);                 
        }               

        std::vector<Contour>::iterator the_max_area;
        double max_area=0;
        double area_value;
        for (std::vector<Contour>::iterator 
ic=temp_poly_list.begin();ic!=temp_poly_list.end();ic++)
        {
                area_value=(*ic).area();
                std::cout<<"the area:"<<area_value<<"\n";
                if (area_value>max_area)
                {
                        max_area=area_value;
                        the_max_area=ic;
                }                       
        }
        std::cout<<"the max area:"<<max_area<<"\n";

        for (std::vector<Contour>::iterator 
ic=temp_poly_list.begin();ic!=temp_poly_list.end();ic++)
        {
                if (ic==the_max_area)
                {
                        std::cout<<"found the outer boundary"<<"\n";
                        if(!(*ic) .is_counterclockwise_oriented())      
(*ic).reverse_orientation();
                        temp_pwhs.outer_boundary().clear();
                        temp_pwhs.outer_boundary()=(*ic);
                        break;
                }
        }


        for (std::vector<Contour>::iterator 
ic=temp_poly_list.begin();ic!=temp_poly_list.end();ic++)
        {
                if (ic!=the_max_area)
                {
                        if(! (*ic).is_clockwise_oriented())     
(*ic).reverse_orientation();
                        temp_pwhs.add_hole((*ic));
                        std::cout<<"insert one hole"<<"\n";
                }
        }
        ifile.close();
        
        std::cout<<"begin to offset"<<"\n";


        double off=0.1;
        PolygonWithHolesPtrVector inner_generated_pswhs = 
                
CGAL::create_interior_skeleton_and_offset_polygons_with_holes_2(off,temp_pwhs);
        std::cout<<"generated "<<inner_generated_pswhs.size()<<"pwhs"<<"\n";
        

        const char *ofilename = "output.txt";
        std::ofstream ofile(ofilename, std::ios::out);

        for( PolygonWithHolesPtrVector::const_iterator pi = 
inner_generated_pswhs.begin() ; pi != inner_generated_pswhs.end() ; ++ pi )
        {
                
                for(Contour::Edge_const_iterator vi = 
(**pi).outer_boundary().edges_begin() ; vi != 
(**pi).outer_boundary().edges_end() ; ++ vi )
                {
                        std::cout<< " segment" << ":" << vi->source().x() << 
"," << vi->source().y() <<"------"<< vi->end().x() << "," << 
vi->end().y()<<"\n";
                        ofile<< " segment" << ":" << vi->source().x() << "," 
<< vi->source().y() << vi->end().x() << "," << vi->end().y();
                        
                }
                std::cout<<"\n";
                ofile<<"\n";
                for (PolygonWithHoles::Hole_const_iterator 
hit=(**pi).holes_begin();hit!=(**pi).holes_end();++hit)
                {
                        for(Contour::Vertex_const_iterator vi = 
hit->vertices_begin() ; vi !=hit->vertices_end() ; ++ vi )
                        {
                                std::cout<<" 
point"<<":"<<vi->x()<<","<<vi->y()<<"\n";
                                ofile<<" 
segment"<<":"<<vi->x()<<","<<vi->y()<<vi->x()<<","<<vi->y();
                        }
                        std::cout<<"\n";
                        ofile<<"\n";
                }
        }

        ofile.close();


}