You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
100 lines
2.7 KiB
100 lines
2.7 KiB
C Copyright(C) 1999-2020 National Technology & Engineering Solutions
|
|
C of Sandia, LLC (NTESS). Under the terms of Contract DE-NA0003525 with
|
|
C NTESS, the U.S. Government retains certain rights in this software.
|
|
C
|
|
C See packages/seacas/LICENSE for details
|
|
|
|
C=======================================================================
|
|
SUBROUTINE PLTLI2(PLL,PUR,N,XV,YV,NO,XVO,YVO)
|
|
DIMENSION PLL(2),PUR(2),XV(*),YV(*),XVO(*),YVO(*)
|
|
DIMENSION P(2),S(2)
|
|
CHARACTER*6 SUBNAM
|
|
PARAMETER (SUBNAM='PLTLI2')
|
|
LOGICAL INSIDE
|
|
|
|
NMAX = NO
|
|
NO = 0
|
|
if (n .gt. 0) then
|
|
S(1) = XV(N)
|
|
S(2) = YV(N)
|
|
DO 2240 I = 1,N
|
|
P(1) = XV(I)
|
|
P(2) = YV(I)
|
|
INSIDE = P(1) .LE. PUR(1)
|
|
IF (INSIDE) THEN
|
|
INSIDE = S(1) .LE. PUR(1)
|
|
IF (INSIDE) THEN
|
|
NO = NO + 1
|
|
IF (NO.GT.NMAX) THEN
|
|
CALL PLTFLU
|
|
CALL SIORPT(SUBNAM,
|
|
* 'Not enough space for output vertices; polygon clip unfinished'
|
|
* ,2)
|
|
RETURN
|
|
|
|
END IF
|
|
|
|
XVO(NO) = P(1)
|
|
YVO(NO) = P(2)
|
|
|
|
ELSE
|
|
TEMP = PUR(2) - PLL(2)
|
|
FP = - (S(1)-PUR(1))*TEMP
|
|
FQ = - (P(1)-PUR(1))*TEMP
|
|
XL = FQ/ (FQ-FP)
|
|
NO = NO + 1
|
|
IF (NO.GT.NMAX) THEN
|
|
CALL PLTFLU
|
|
CALL SIORPT(SUBNAM,
|
|
* 'Not enough space for output vertices; polygon clip unfinished'
|
|
* ,2)
|
|
RETURN
|
|
|
|
END IF
|
|
|
|
XVO(NO) = P(1) + XL* (S(1)-P(1))
|
|
YVO(NO) = P(2) + XL* (S(2)-P(2))
|
|
NO = NO + 1
|
|
IF (NO.GT.NMAX) THEN
|
|
CALL PLTFLU
|
|
CALL SIORPT(SUBNAM,
|
|
* 'Not enough space for output vertices; polygon clip unfinished'
|
|
* ,2)
|
|
RETURN
|
|
|
|
END IF
|
|
|
|
XVO(NO) = P(1)
|
|
YVO(NO) = P(2)
|
|
END IF
|
|
|
|
ELSE
|
|
INSIDE = S(1) .LE. PUR(1)
|
|
IF (INSIDE) THEN
|
|
TEMP = PUR(2) - PLL(2)
|
|
FP = - (S(1)-PUR(1))*TEMP
|
|
FQ = - (P(1)-PUR(1))*TEMP
|
|
XL = FQ/ (FQ-FP)
|
|
NO = NO + 1
|
|
IF (NO.GT.NMAX) THEN
|
|
CALL PLTFLU
|
|
CALL SIORPT(SUBNAM,
|
|
* 'Not enough space for output vertices; polygon clip unfinished'
|
|
* ,2)
|
|
RETURN
|
|
|
|
END IF
|
|
|
|
XVO(NO) = P(1) + XL* (S(1)-P(1))
|
|
YVO(NO) = P(2) + XL* (S(2)-P(2))
|
|
END IF
|
|
|
|
END IF
|
|
|
|
S(1) = P(1)
|
|
S(2) = P(2)
|
|
2240 CONTINUE
|
|
end if
|
|
RETURN
|
|
|
|
END
|
|
|