| 1 |
|
1 |
/*****************************************************************
|
| 2 |
|
|
|
| 3 |
|
|
m2d_int_seg_seg.c Type:Func
|
| 4 |
|
|
|
| 5 |
|
|
Intersection entre segment AB et le sement MN
|
| 6 |
|
|
|
| 7 |
|
|
Date de creation : Wed Feb 19 14:36:10 1997
|
| 8 |
|
|
|
| 9 |
|
|
Derniere version : Thu May 8 10:09:04 1997
|
| 10 |
|
|
|
| 11 |
|
|
|
| 12 |
|
|
|
| 13 |
|
|
|
| 14 |
|
|
|
| 15 |
|
|
|
| 16 |
|
|
|
| 17 |
|
|
|
| 18 |
|
|
|
| 19 |
|
|
|
| 20 |
|
|
|
| 21 |
|
|
|
| 22 |
|
|
|
| 23 |
|
|
|
| 24 |
|
|
|
| 25 |
|
|
Vincent FRANCOIS
|
| 26 |
|
|
|
| 27 |
|
|
*****************************************************************/
|
| 28 |
|
|
|
| 29 |
|
|
|
| 30 |
|
|
|
| 31 |
|
|
|
| 32 |
|
|
|
| 33 |
|
|
/**************************/
|
| 34 |
|
|
/* include */
|
| 35 |
|
|
#include <stdio.h>
|
| 36 |
|
|
#include <math.h>
|
| 37 |
|
|
#include <math.h>
|
| 38 |
|
|
#include "const.h"
|
| 39 |
|
|
#include "struct.h"
|
| 40 |
|
|
#include "memoire.h"
|
| 41 |
|
|
#include "prototype.h"
|
| 42 |
|
|
|
| 43 |
|
|
|
| 44 |
|
|
/**************************/
|
| 45 |
|
|
/* variables globales */
|
| 46 |
|
|
extern struct environnement env;
|
| 47 |
|
|
extern struct s_mesh *mesh;
|
| 48 |
|
|
|
| 49 |
|
|
/**************************/
|
| 50 |
|
|
/* programme principal */
|
| 51 |
|
|
#define VRAI 1
|
| 52 |
|
|
#define FAUX 0
|
| 53 |
|
|
|
| 54 |
|
|
|
| 55 |
|
|
|
| 56 |
|
|
int m2d_int_seg_seg(int a,int b,int m,int n)
|
| 57 |
|
|
{
|
| 58 |
|
|
struct s_noeud *noa,*nob,*nom,*non;
|
| 59 |
|
|
float ab[3],nm[3],am[3],an[3],det,sol1,sol2,tmp;
|
| 60 |
|
|
float eps,eps2;
|
| 61 |
|
|
float ua,va,ub,vb,un,vn,um,vm,du,dv;
|
| 62 |
|
|
int equation[4],ne1,ne2;
|
| 63 |
|
|
|
| 64 |
|
|
|
| 65 |
|
|
noa=ADRESSE(a,noeud,mesh->);
|
| 66 |
|
|
nob=ADRESSE(b,noeud,mesh->);
|
| 67 |
|
|
nom=ADRESSE(m,noeud,mesh->);
|
| 68 |
|
|
non=ADRESSE(n,noeud,mesh->);
|
| 69 |
|
|
/* decalage */
|
| 70 |
|
|
if (mesh->rev_u!=0.) du=0.5*mesh->rev_u-noa->u; else du=0.;
|
| 71 |
|
|
if (mesh->rev_v!=0.) dv=0.5*mesh->rev_v-noa->v; else dv=0.;
|
| 72 |
|
|
eval_decale(&ua,du,noa->u,U);
|
| 73 |
|
|
eval_decale(&va,dv,noa->v,V);
|
| 74 |
|
|
eval_decale(&ub,du,nob->u,U);
|
| 75 |
|
|
eval_decale(&vb,dv,nob->v,V);
|
| 76 |
|
|
eval_decale(&un,du,non->u,U);
|
| 77 |
|
|
eval_decale(&vn,dv,non->v,V);
|
| 78 |
|
|
eval_decale(&um,du,nom->u,U);
|
| 79 |
|
|
eval_decale(&vm,dv,nom->v,V);
|
| 80 |
|
|
ab[0]=ub-ua;
|
| 81 |
|
|
ab[1]=vb-va;
|
| 82 |
|
|
ab[2]=0.;
|
| 83 |
|
|
nm[0]=um-un;
|
| 84 |
|
|
nm[1]=vm-vn;
|
| 85 |
|
|
nm[2]=0.;
|
| 86 |
|
|
am[0]=um-ua;
|
| 87 |
|
|
am[1]=vm-va;
|
| 88 |
|
|
am[2]=0.;
|
| 89 |
|
|
equation[0]=1; /* etat de l'equation 0 */
|
| 90 |
|
|
equation[1]=1;
|
| 91 |
|
|
equation[2]=1;
|
| 92 |
|
|
equation[3]=3; /* cette variable comporte le bilan du nombre d'equation */
|
| 93 |
|
|
eps2=PSCA(ab,ab);
|
| 94 |
|
|
eps=(float)sqrt((double)eps2);
|
| 95 |
|
|
eps=eps*0.0001;
|
| 96 |
|
|
eps2=eps2*0.0001;
|
| 97 |
|
|
/* recherche du nombre d'equation -> inter franche ou para ou confondu */
|
| 98 |
|
|
if ( (EGAL(ab[0],0,eps)) && (EGAL(nm[0],0,eps)) )
|
| 99 |
|
|
if (EGAL(am[0],0,eps)) equation[0]=0; else return(FAUX);
|
| 100 |
|
|
if ( (EGAL(ab[1],0,eps)) && (EGAL(nm[1],0,eps)) )
|
| 101 |
|
|
if (EGAL(am[1],0,eps)) equation[1]=0; else return(FAUX);
|
| 102 |
|
|
if ( (EGAL(ab[2],0,eps)) && (EGAL(nm[2],0,eps)) )
|
| 103 |
|
|
if (EGAL(am[2],0,eps)) equation[2]=0; else return(FAUX);
|
| 104 |
|
|
equation[3]=equation[0]+equation[1]+equation[2];
|
| 105 |
|
|
if (equation[3]==3)
|
| 106 |
|
|
{
|
| 107 |
|
|
det=DETER(ab[0],nm[0],ab[1],nm[1]);
|
| 108 |
|
|
if ((float)fabs((double)det)>eps2)
|
| 109 |
|
|
{
|
| 110 |
|
|
det=1/det;
|
| 111 |
|
|
sol1=det*DETER(am[0],nm[0],am[1],nm[1]);
|
| 112 |
|
|
sol2=det*DETER(ab[0],am[0],ab[1],am[1]);
|
| 113 |
|
|
if ( (float)fabs((double)(sol1*ab[2]-sol2*nm[2]-am[2]))>eps2) return(FAUX);
|
| 114 |
|
|
return(m2d_ex_sol(sol1,sol2,1));
|
| 115 |
|
|
}
|
| 116 |
|
|
else
|
| 117 |
|
|
{
|
| 118 |
|
|
equation[0]=0;
|
| 119 |
|
|
equation[3]=2;
|
| 120 |
|
|
/* on verifie la compatibilite des deux equations dont le det est nul*/
|
| 121 |
|
|
if (ab[0]!=0) tmp=ab[1]*am[0]/ab[0]; else tmp=nm[1]*am[0]/nm[0];
|
| 122 |
|
|
if (!(EGAL(tmp,am[1],eps))) return(FAUX);
|
| 123 |
|
|
}
|
| 124 |
|
|
}
|
| 125 |
|
|
if (equation[3]==2)
|
| 126 |
|
|
{
|
| 127 |
|
|
/* on repere les equations qui existent */
|
| 128 |
|
|
if (equation[0]!=0)
|
| 129 |
|
|
{
|
| 130 |
|
|
ne1=0;
|
| 131 |
|
|
if (equation[1]!=0) ne2=1; else ne2=2;
|
| 132 |
|
|
}
|
| 133 |
|
|
else
|
| 134 |
|
|
{
|
| 135 |
|
|
ne1=1;
|
| 136 |
|
|
ne2=2;
|
| 137 |
|
|
}
|
| 138 |
|
|
|
| 139 |
|
|
det=DETER(ab[ne1],nm[ne1],ab[ne2],nm[ne2]);
|
| 140 |
|
|
if ((float)fabs((double)det)>eps2)
|
| 141 |
|
|
{
|
| 142 |
|
|
det=1/det;
|
| 143 |
|
|
sol1=det*DETER(am[ne1],nm[ne1],am[ne2],nm[ne2]);
|
| 144 |
|
|
sol2=det*DETER(ab[ne1],am[ne1],ab[ne2],am[ne2]);
|
| 145 |
|
|
return(m2d_ex_sol(sol1,sol2,1));
|
| 146 |
|
|
}
|
| 147 |
|
|
else
|
| 148 |
|
|
{
|
| 149 |
|
|
equation[ne1]=0;
|
| 150 |
|
|
equation[3]=1;
|
| 151 |
|
|
/* on verifie la compatibilite des deux equations dont le det est nul */
|
| 152 |
|
|
if (ab[ne1]!=0) tmp=ab[ne2]*am[ne1]/ab[ne1]; else tmp=nm[ne2]*am[ne1]/nm[ne1];
|
| 153 |
|
|
if (!(EGAL(tmp,am[ne2],eps))) return(FAUX);
|
| 154 |
|
|
}
|
| 155 |
|
|
|
| 156 |
|
|
}
|
| 157 |
|
|
if (equation[3]==1)
|
| 158 |
|
|
{
|
| 159 |
|
|
/* on repere l' equation qui existe */
|
| 160 |
|
|
if (equation[0]!=0) ne1=0; else
|
| 161 |
|
|
if (equation[1]!=0) ne1=1; else ne1=2;
|
| 162 |
|
|
an[0]=un-ua;
|
| 163 |
|
|
an[1]=vn-va;
|
| 164 |
|
|
an[2]=0.;
|
| 165 |
|
|
tmp=1/ab[ne1];
|
| 166 |
|
|
sol1=am[ne1]*tmp;
|
| 167 |
|
|
sol2=an[ne1]*tmp;
|
| 168 |
|
|
return(m2d_ex_sol(sol1,sol2,2));
|
| 169 |
|
|
}
|
| 170 |
|
|
return(0);
|
| 171 |
|
|
}
|
