; DRAW3D (LISTING 4)››MODULE:BYTE vflag=[0],gflag=[7]›INT sx,sy,mag=[3],cx=[80],cy=[90]›  ,rx=[0],ry=[0],rz=[0],ri=[30]›CARD sa1,dl1,dl2,lin16,lin17,lin18›  ,lin19,lin20,lin21,lin22,lin23,lin15›INT ARRAY P(809),eye,foc,R(9),E(9),M(9)›  ,Q=[21:10 5 5:100:0 0 0:0:›  50 0 0:18:0 0 0:2:0 50 0:2:›  0 0 0:18:0 0 40:2:10 0 0:17:›  10 50 0:1:20 50 0:17:20 0 0:1:›  30 0 0:17:30 50 0:1:40 50 0:17:›  40 0 0:1:0 10 0:19:50 10 0:3:›  50 20 0:19:0 20 0:3:0 30 0:19:›  50 30 0:3:50 40 0:19:0 40 0:3]››PROC FixP(INT ARRAY Q):INT i,j›Zero(P,1618):j=4*Q(0)+8›FOR i=0 TO j DO P(i)=Q(i) OD›eye=P+2:foc=P+10:RETURN››PROC Rot(INT ARRAY v):INT x,y,z,s,c›y=v(1)›v(1)=y*cos(rx)/128:v(2)=y*sin(rx)/128›x=v(0):z=v(2):s=sin(ry):c=cos(ry)›v(0)=(x*c-z*s)/128:v(2)=(x*s+z*c)/128›x=v(0):y=v(1):s=sin(rz):c=cos(rz)›v(0)=x*c-y*s:v(1)=x*s+y*c:v(0)==/128›v(1)==/128:Normize(v):RETURN› ›PROC FixR():INT ARRAY v(3),w(3),u(3)›v(0)=128:v(1)=0:v(2)=0:Rot(v)›w(0)=0:w(1)=128:w(2)=0:Rot(w)›Vprod(v,w,u):Normize(u)›R(0)=v(0):R(1)=v(1):R(2)=v(2)›R(3)=w(0):R(4)=w(1):R(5)=w(2)›R(6)=u(0):R(7)=u(1):R(8)=u(2):RETURN›   ›PROC FixE():INT s›E(6)=eye(0):E(7)=eye(1):E(8)=eye(2)›Normize(E+12)›IF E(8)=0 THEN E(3)=0:E(4)=0:E(5)=128›ELSEIF E(6)=0 AND E(7)=0 THEN›  E(3)=0:E(4)=128:E(5)=0›ELSE E(3)=-E(6):E(4)=-E(7)›  E(5)=E(6)*E(6):E(5)==+E(7)*E(7)›  E(5)==/E(8):Normize(E+6)›  IF E(8)<0 THEN E(3)=-E(3):E(4)=-E(4)›    E(5)=-E(5)›  FI›FI Vprod(E+6,E+12,E):Normize(E):RETURN››PROC FixM()›M(0)=Vdot(R,E):M(3)=Vdot(R,E+6)›M(1)=Vdot(R+6,E):M(4)=Vdot(R+6,E+6)›M(2)=Vdot(R+12,E):M(5)=Vdot(R+12,E+6)›Normize(M):Normize(M+6)›Vprod(M,M+6,M+12):Normize(M+12):RETURN››PROC Maksxsy(INT ARRAY v):BYTE i›INT px,py,pz,t,d:INT ARRAY w(3)›FOR i=0 TO 2 DO w(i)=v(i)-foc(i) OD›IF vflag=1 THEN px=Vdot(w,M)/128›  py=Vdot(w,M+6)/128›  sx=cx+mag*px/2:sy=cy-mag*py/2›ELSE d=eye(3):t=mag*d/8›  px=Vdot(w,M)/128:py=Vdot(w,M+6)/128›  pz=Vdot(w,M+12)/128›  d==-pz:IF d<4 THEN d=4 FI:d==/4›  sx=t*px/d:sy=t*py/d:sx==+cx:sy=cy-sy›FI RETURN››PROC CLR():Zero(sa1,7680):RETURN››PROC Draw(INT ARRAY P):BYTE i›INT ARRAY pt›pt=P+10›FOR i=1 TO P(0) DO pt==+8 Maksxsy(pt)›  Kolor(pt(3) & 15)›  IF pt(3)<16 THEN LineTo(sx,sy)›  ELSE Dot(sx,sy):xnow=sx:ynow=sy FI›OD RETURN››