1.7.9. DRAWING A PARALLELEPIPED WITH A PARALLEL VIEW

	program p79
	include 'PHIGS.H'

	integer wkid, viewid, scenid,cubid,systid, listid(2)
	real viewpt(6)
	data wkid, viewid, scenid  / 1, 1, 10/
	data cubid,systid,listid /11,12, 11,12/
	data zoom                  / 0.8 /
	data xmin,ymin,zmin, xmax,ymax,zmax  / 10.,10.,5., 20.,30.,35. /
	data viewpt /0.,1., 0.,1., 0.,1./

c---------------------------------------------------------------------

c	open PHIGURE and X-window type workstation */
	call topph (6)
	call topwk (wkid,30,8887)

c	define a cubic 3D working domain
	size = max(xmax-xmin,ymax-ymin)
	size = max(size,zmax-zmin)/2.0
	xmid = (xmin+xmax)/2.0
	ymid = (ymin+ymax)/2.0
	zmid = (zmin+zmax)/2.0
	xmindo = xmid - size
	xmaxdo = xmid + size
	ymindo = ymid - size
	ymaxdo = ymid + size
	zmindo = zmid - size
	zmaxdo = zmid + size
	call tdoma3 (xmindo,ymindo,zmindo, xmaxdo,ymaxdo,zmaxdo)

c	build parallelepiped
	call tcube (cubid, xmin,ymin,zmin, xmax,ymax,zmax)

c	build dotted line-type marker
	call tcosya (systid, xmid,ymid,zmid ,xmax,ymax,zmax,
	+            'X','Y','Z', 0.1,0.1)

c	insert a PHIGS-type line attribute in the structure 
	call tsln (systid,-1,PLDASH)

c	define scene
	call TSCENE (scenid,2,listid,viewid)

c	define a centered 2D view 
	call tv3slz (wkid,viewid,0.5,0.5,0.5,55.,25.,zoom,viewpt)
	
c	display on workstation 
	call ppost (wkid,scenid,1.0)
	call prst (wkid,PALWAY)

c	close workstation and PHIGURE 
	call tclwk (wkid)
	call tclph 
	end

This program is identical to n°8, except that the structures are displayed in parallel projection by replacing TV3SPZ with TV3SLZ.