Newer
Older
!------------------------------------------------------------------------------|
!------------------------------------------------------------------------------|
! |
! ||===\\ |
! || \\ |
! || || //==\\ || || //==|| ||/==\\ |
! || || || || || || || || || || |
! || // || || || || || || || |
! ||===// \\==// \\==\\ \\==\\ || |
! |
!------------------------------------------------------------------------------|
!------------------------------------------------------------------------------|
! |
! COMPUTE_NORMALS Apr. 2007 |
! |
!------------------------------------------------------------------------------|
!------------------------------------------------------------------------------|
subroutine compute_normals (ns,x,y,z,nt,icon,xn,yn,zn)
!------------------------------------------------------------------------------|
!(((((((((((((((( Purpose of the routine ))))))))))))))))))))))))))))))))))))))
!------------------------------------------------------------------------------|
! given a set of points, and a connectivity array of their triangulation,
! this routine computes the normal to each point through cross-products:
! at first one computes the normal to each triangle and add the vector to the
! three points that make the triangle
! then one loops over the points, and normalises the vectors.
!------------------------------------------------------------------------------|
!(((((((((((((((( declaration of the subroutine arguments ))))))))))))))))))))
!------------------------------------------------------------------------------|
Dave Whipp
committed
use mpi
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
implicit none
integer ns
double precision x(ns),y(ns),z(ns)
integer nt
integer icon(3,nt)
double precision xn(ns),yn(ns),zn(ns)
!------------------------------------------------------------------------------|
!(((((((((((((((( declaration of the subroutine internal variables )))))))))))))
!------------------------------------------------------------------------------|
integer i,i1,i2,i3,ij,k
integer iproc,nproc,ierr
integer, dimension(:),allocatable :: nb
double precision x1,x2,x3
double precision y1,y2,y3
double precision z1,z2,z3
double precision xne,yne,zne
double precision xyzn
!-------------------------------------------------------------------------------
!-------------------------------------------------------------------------------
call mpi_comm_size (mpi_comm_world,nproc,ierr)
call mpi_comm_rank (mpi_comm_world,iproc,ierr)
allocate(nb(ns))
nb=0
xn=0.d0
yn=0.d0
zn=0.d0
do i=1,nt
i1=icon(1,i)
i2=icon(2,i)
i3=icon(3,i)
x1=x(i1)
x2=x(i2)
x3=x(i3)
y1=y(i1)
y2=y(i2)
y3=y(i3)
z1=z(i1)
z2=z(i2)
z3=z(i3)
xne=(y2-y1)*(z3-z1)-(y3-y1)*(z2-z1)
yne=(z2-z1)*(x3-x1)-(z3-z1)*(x2-x1)
zne=(x2-x1)*(y3-y1)-(x3-x1)*(y2-y1)
xyzn=sqrt(xne**2+yne**2+zne**2)
xne=xne/xyzn
yne=yne/xyzn
zne=zne/xyzn
do k=1,3
ij=icon(k,i)
xn(ij)=xn(ij)+xne
yn(ij)=yn(ij)+yne
zn(ij)=zn(ij)+zne
nb(ij)=nb(ij)+1
enddo
enddo
do i=1,ns
xyzn=sqrt(xn(i)**2+yn(i)**2+zn(i)**2)
xn(i)=xn(i)/xyzn
yn(i)=yn(i)/xyzn
zn(i)=zn(i)/xyzn
enddo
if (minval(nb).eq.0) then
do i=1,ns
if (nb(i).eq.0.and.iproc.eq.0) then
write (8,*) 'Particle ',i,' at ',x(i),y(i),z(i),' not connected'
end if
enddo
call stop_run ('error in compute_normals_from_triangles$')
else
if (iproc.eq.0) then
write(8,*) 'in compute_normals_from_triangles:'
write(8,*) 'minval(nb)=',minval(nb),' neighbours'
write(8,*) 'maxval(nb)=',maxval(nb),' neighbours'
end if
end if
deallocate(nb)
return
end
!-------------------------------------------------------------------------------
!-------------------------------------------------------------------------------