$alias fdopen='fdopen'(%val,%ref)      include 'phigs.f1.h'			! get the HP-PHIGS aliases      program WireMesh				! program "WireMesh.f"      include 'phigs.f2.h'			! get the HP-PHIGS constants      integer*4	WorkstnID			! workstation identifier      parameter (WorkstnID=1)			! value chosen by the user      integer*4	ConnID				! connection identifier      integer*4	WorkstnType			! workstation type      parameter (WorkstnType=POIDDX)		! out/in, direct, sngl bfr, X      real	CtrlPtsX(12),CtrlPtsY(12),CtrlPtsZ(12)	! control points      data	CtrlPtsX /.0,.5,1., .0,.5,1., .0,.5,1., .0,.5,1./      data	CtrlPtsY /.0,.3,.2, .1,.5,.4, .3,.4,.1, .0,.2,.3/      data	CtrlPtsZ /.0,.0,.0, .3,.3,.3, .6,.6,.6, .9,.9,.9/      real	uKnotVector(6), vKnotVector(8)	! knot vectors      data	uKnotVector /0., 0., 0., 1., 1., 1./      data	vKnotVector /0., 0., 0., 0., 1., 1., 1., 1./      real	StepSizeData(4)			! sent to "pprec"      data	StepSizeData /.1, .1, .1, .1/	! u, v exterior; u, v interior      integer*4	TheMesh, MeshLabel		! structure identifier, label      parameter (TheMesh=1, MeshLabel=1)	! values chosen by the user      real	ThetaMin,ThetaMax, dTheta, Theta! loop control variables      parameter (ThetaMin=0., ThetaMax=410., dTheta=.4)      real	xform(4,4)			! transformation matrix      integer*4	Error				! error-return variable      character*80 DataRec(10)			! sent to "pprec"      integer*4	DataRecLen			! ditto      integer*4	Dummy(1)			! dummy variable      integer*4	u, v				! loop control variables      integer*4	I, Iu, Iv			! temporary array indexes      integer*4 fdopen				! to get file descriptor      real	rad, deg			! type the statement function      rad(deg)=	((deg)*3.14159265358979/180.)	! convert degrees to radians      call popph(fdopen(fnum(7), 'w'//char(0)), 0)	! open phigs      call pue004('/dev/screen/phigs_window', ConnID)	! get connection ID      call popwk(WorkstnID, ConnID, WorkstnType)! open workstation      call ppost(WorkstnID, TheMesh, 1.)	! mark structure for display      !=== define the spline-generating structure ============================      call popst(TheMesh)			! open structure      !--- set up transformations --------------------------------------------      call ptr3(-.5, .0, -.5, Error, xform)	! 3d translate: to origin      call pslmt3(xform, PCREPL)		! set local transformation      call psc3(.7, .7, .7, Error, xform)	! 3d scale to 70%      call pslmt3(xform, PCPOST)		! set local transformation      call prox(rad(30), Error, xform)		! rotate about X axis      call pslmt3(xform, PCPOST)		! set local transformation      call proy(rad(0), Error, xform)		! rotate about Y axis      call plb(MeshLabel)			! label      call pslmt3(xform, PCPOST)		! set local transformation      call ptr3(.5, .3, .5, Error, xform)	! 3d translate: into position      call pslmt3(xform, PCPOST)		! set local transformation      !--- delta t (independent variable) of 0.1 -----------------------------      call pprec(0, Dummy, 4, StepSizeData,	! pack data record     +	0, 0, '', 10, Error, DataRecLen, DataRec)      if (Error .ne. 0) then          print *,"Error", Error, "in pprec."          stop      end if      call pssac(-3, DataRecLen, DataRec)	! set surface approx. criteria      !--- define the b-spline surface ---------------------------------------      call pspsc(PIEPC, 0, Dummy)		! set parametric surface char.      call pbss3(				! non-uniform b-spline surface     +	3, 4,					!   u, v order     +	6, 8,					!   u, v knots     +	uKnotVector, vKnotVector,		!   u, v knot vectors     +	PNRAT,					!   non-rational surface     +	3, 4,					!   u, v control points     +	CtrlPtsX, CtrlPtsY, CtrlPtsZ,		!   control points' XYZs     +	Dummy,					!   dummy homogeneous coords     +	0, Dummy)				!   no trimming curves      !--- draw control-point grid -------------------------------------------      call psln(PLDOT)				! set line type      do u=1, 3          do v=1, 4              I=(v-1)*3+u			! index of X(u,v)              Iu=(v-1)*3+u+1			! index of X(u+1,v)              Iv=v*3+u				! index of X(u,v+1)              if (u .lt. 3)			! unless on right edge...     +          call Line(CtrlPtsX(I), CtrlPtsY(I), CtrlPtsZ(I),     +          CtrlPtsX(Iu), CtrlPtsY(Iu), CtrlPtsZ(Iu))              if (v .lt. 4)			! unless on bottom edge...     +          call Line(CtrlPtsX(I), CtrlPtsY(I), CtrlPtsZ(I),     +          CtrlPtsX(Iv), CtrlPtsY(Iv), CtrlPtsZ(Iv))          end do      end do      call pclst				! close structure      !=== rotate the spline surface =========================================      Theta=ThetaMin				! initialize loop control var.      do while (Theta .lt. ThetaMax)		! for each angle...          call popst(TheMesh)			! open structure          call proy(rad(Theta), Error, xform)	! rotate about Y axis          call psep(1)				! set element pointer: BOS          call pseplb(MeshLabel)		! set element pointer at label          call posep(1)				! offset element pointer: +1          call psedm(PREPLC)			! set edit mode          call pslmt3(xform, PCPOST)		! set local transformation          call pclst				! close structure          call puwk(WorkstnID, PPERFO)		! update the workstation          Theta=Theta+dTheta			! increment angle      end do      call pclwk(WorkstnID)			! close workstation      call pclph				! close phigs      stop					! stop processing      end					! end of program!*****************************************************************************      subroutine Line(X1, Y1, Z1, X2, Y2, Z2)      real	X1, Y1, Z1, X2, Y2, Z2		! "from" point, "to" point            real	X(2), Y(2), Z(2)		! for 3D polyline            X(1)=X1					! \      Y(1)=Y1					!  \      Z(1)=Z1					!   \ put the individual      X(2)=X2					!   / values into the arrays      Y(2)=Y2					!  /      Z(2)=Z2					! /      call ppl3(2, X, Y, Z)			! polyline 3D      return      end