      SUBROUTINE RSURFU(H,P,TGT,DNDS,X,TIME,U,CINAME,SLNAME,
     1   MSNAME,NOEL,NODE,LCLOSE)
C     
      INCLUDE 'ABA_PARAM.INC'
C     
      CHARACTER*80 CINAME,SLNAME,MSNAME
      DIMENSION P(3),TGT(3,2),DNDS(3,2),X(3,2),TIME(2),U(6,2)
C     
C     DEFINE THE FOLLOWING QUANTITIES:
C     A = RADIUS 'A' OF THE SPHERICAL HEAD
C     SINA = SINE (CONE ANGLE ALPHA)
C     COSA = COSINE (CONE ANGLE ALPHA)
C     Z0 = ORIGINAL 'Z' COORDINATE OF POINT 'Q'
C     
      A=5.0
      SINA=0.5
      COSA=0.86602
      Z0=6.0
      ZQ=Z0 + U(2,2)
C     
C     TEST FOR SEGMENT
C     
      IF(X(1,1)*SINA/COSA.LT.ZQ-X(2,1))THEN
C     
C     SPHERE
C     
         B=SQRT(X(1,1)**2 + (X(2,1)-ZQ)**2)
         H=A-B
         COSB=X(1,1)/B
         SINB=(ZQ-X(2,1))/B
         P(1)=A*COSB
         P(2)=ZQ-A*SINB
         TGT(1,1)=-SINB
         TGT(2,1)=-COSB
         DNDS(1,1)=-SINB/A
         DNDS(2,1)=-COSB/A
      ELSE
C     CONE
         H=-X(1,1)*COSA+(X(2,1)-ZQ)*SINA+A
         P(1)=X(1,1) + H*COSA
         P(2)=X(2,1)- H*SINA
         TGT(1,1)=-SINA
         TGT(2,1)=-COSA
         DNDS(1,1)=0.
         DNDS(2,1)=0.
      END IF
      RETURN
      END
      

