source: issm/trunk-jpl/src/c/shared/TriMesh/OrderSegments.cpp@ 10937

/*
 * OrderSegments.c: 
 * reorder segments so that their normals point outside the domain outline.
 */
#include "./trimesh.h"

int OrderSegments(double** psegments,int nseg, double* index,int nel){
        
        /*Error management: */
        int i;
        int noerr=1;

        /*Input: */
        double* segments=NULL;

        /*vertex indices: */
        double A,B;
        /*element indices: */
        int el;


        /*Recover segments: */
        segments=*psegments;

        for (i=0;i<nseg;i++){
                A=*(segments+3*i+0);
                B=*(segments+3*i+1);
                el=*(segments+3*i+2)-1; //after AssociateSegmentToElement, el was a matlab index, we need the c index now.

                if (*(index+3*el+0)==A){
                        if (*(index+3*el+2)==B){
                                *(segments+3*i+0)=B;
                                *(segments+3*i+1)=A;
                        }
                }
                else if (*(index+3*el+1)==A){
                        if (*(index+3*el+0)==B){
                                *(segments+3*i+0)=B;
                                *(segments+3*i+1)=A;
                        }
                }
                else{
                        if (*(index+3*el+1)==B){
                                *(segments+3*i+0)=B;
                                *(segments+3*i+1)=A;
                        }
                }
        }

        /*Assign output pointers: */
        *psegments=segments;
        return noerr;
}