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% tetrapodes.mp
% L. Nobre G.
% 2009
input featpost3Dplus2D;
verbatimtex
\documentclass{article}
\usepackage{palatino}
\usepackage{mathpazo}
\begin{document}
etex
f := (10,2,3);
Spread := 50;
def rotatearoundZ( expr P, A ) =
((X(P)*cosd(A)-Y(P)*sind(A),X(P)*sind(A)+Y(P)*cosd(A),Z(P)))
enddef;
beginfig(1);
numeric margia, margib, margic, raycil, raysph, angul;
color ca, cb;
path sph;
margia = 0.10;
margib = 1.52;
margic = 0.05;
raycil = 0.55;
raysph = 1.00;
angul = 30;
ca := (0,-raysph-margia-raycil,0);
cb := (-raycil-margic,0,raysph+margib);
rigorousdisc(0,true,ca,raycil,cb-ca);
ca := rotatearoundZ((-raysph-margia-raycil,0,0),angul);
cb := rotatearoundZ((0,raycil+margic,-raysph-margib),angul);
rigorousdisc(0,true,ca,raycil,cb-ca);
sph = rigorousfearpath(black,raysph);
unfill sph;
draw sph;
ca := rotatearoundZ((raysph+margia+raycil,0,0),angul);
cb := rotatearoundZ((0,-raycil-margic,-raysph-margib),angul);
rigorousdisc(0,true,ca,raycil,cb-ca);
ca := (0,raysph+margia+raycil,0);
cb := (raycil+margic,0,raysph+margib);
rigorousdisc(0,true,ca,raycil,cb-ca);
endfig;
beginfig(2);
numeric tro;
tro = 2;
V1 := (tro,0,0);
V2 := (0,tro,0);
V3 := (-tro,0,0);
V4 := (0,-tro,0);
V5 := (1,1,1);
V6 := (-1,1,1);
V7 := (-1,-1,1);
V8 := (1,-1,1);
V9 := (1,1,-1);
V10 := (-1,1,-1);
V11 := (-1,-1,-1);
V12 := (1,-1,-1);
V13 := (0,0,tro);
V14 := (0,0,-tro);
for i=1 upto 14:
V[i] := rotatearoundZ(V[i],45);
V[i] := (0.4*X(V[i]),Y(V[i]),1.5*Z(V[i]));
endfor;
makeface1(1,5,13,8);
makeface2(2,6,13,5);
makeface3(3,7,13,6);
makeface4(4,8,13,7);
makeface5(1,5,2,9);
makeface6(2,6,3,10);
makeface7(3,7,4,11);
makeface8(4,8,1,12);
makeface9(1,9,14,12);
makeface10(2,10,14,9);
makeface11(3,11,14,10);
makeface12(4,12,14,11);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
f := 2*(5,5,1.5);
Spread := 50;
pickup pencircle scaled 1pt;
sharpraytrace;
endfig;
def spacedistort( expr Pos, Ref, Fac ) =
( Pos + cdotprod( Pos, Ref )*Fac*Ref )
enddef;
beginfig(3);
f := (15,10,5);
Spread := 50;
numeric numsidecells, numlimcorner, i, j, k, cx, cy, cz, faca, facb;
numeric ar, scal;
color posa, posb, posc, posd, thisoria, thisorib, thisoric,thatori;
path ball;
numsidecells = 7;
numlimcorner = 2*numsidecells+2;
faca = 0.0;
facb = 0.0;
ar = 1.0;
scal = 0.14;
thisoria = N(( 1, 1, 1));
thisorib = N(( 1,-2, 1));
thisoric = 0.5*sqrt(3)*(1,1,1);
thatori = ncrossprod(thisoric,thisorib);
for i=1 upto numsidecells:
cx := i-0.5*numsidecells-1;
for j=1 upto numsidecells:
cy := j-0.5*numsidecells-1;
for k=1 upto numsidecells:
cz := k-0.5*numsidecells-1;
if i+j+k < numlimcorner+1:
posa := spacedistort( (cx,cy,cz), thisoria, faca );
posa := spacedistort( posa, thisorib, facb );
posb := spacedistort( (cx-0.5,cy+0.5,cz), thisoria, faca );
posb := spacedistort( posb, thisorib, facb );
posc := spacedistort( (cx-0.5,cy,cz+0.5), thisoria, faca );
posc := spacedistort( posc, thisorib, facb );
posd := spacedistort( (cx,cy+0.5,cz+0.5), thisoria, faca );
posd := spacedistort( posd, thisorib, facb );
% whatisthis(posa,scal*ar*thatori,scal*thisorib,1,1);
% whatisthis(posb,scal*ar*thatori,scal*thisorib,1,1);
% whatisthis(posc,scal*ar*thatori,scal*thisorib,1,1);
% whatisthis(posd,scal*ar*thatori,scal*thisorib,1,1);
ball := rigorousfearpath( posa, scal ); unfill ball; draw ball;
ball := rigorousfearpath( posb, scal ); unfill ball; draw ball;
ball := rigorousfearpath( posc, scal ); unfill ball; draw ball;
ball := rigorousfearpath( posd, scal ); unfill ball; draw ball;
fi;
endfor;
endfor;
endfor;
endfig;
end;
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