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% lcurvature.mp
% L. Nobre G.
% 2002
input featpost3Dplus2D;
verbatimtex
\documentclass{article}
\usepackage{beton}
\usepackage{concmath}
\usepackage{ccfonts}
\begin{document}
etex
beginfig(1);
f := (5,3,4);
Spread := 70;
numeric gridstep, anglstep, cylength, cyradius, numcylis;
numeric i, j, curcoord, vcx, vcy, vcz, curangle, curnorma;
numeric major, othcoord, othangle;
color base, lenvec;
cylength := 0.1;
cyradius := 0.3;
gridstep := cyradius*2.2;
anglstep := 10;
numcylis := 5;
major := 0.35*gridstep*numcylis;
for i=1 upto numcylis: % bend
curnorma := i-0.5*(numcylis+1);
curangle := curnorma*anglstep;
vcx := cylength*cosd(curangle);
vcy := 0;
vcz := cylength*sind(curangle);
base := major*(sind(curangle),-1,-cosd(curangle));
lenvec := (vcx,vcy,vcz);
rigorousdisc( 0, true,base,cyradius,lenvec);
endfor;
for i=1 upto numcylis: % twist
curnorma := i-0.5*(numcylis+1);
curcoord := curnorma*gridstep;
curangle := curnorma*anglstep;
vcx := 0;
vcy := cylength*sind(curangle);
vcz := cylength*cosd(curangle);
base := (curcoord,-vcy/2-major,-vcz/2+major);
lenvec := (vcx,vcy,vcz);
rigorousdisc( 0, true,base,cyradius,lenvec);
endfor;
for i=1 upto numcylis: % splay
curnorma := i-0.5*(numcylis+1);
curcoord := curnorma*gridstep;
curangle := curnorma*anglstep;
vcx := cylength*sind(curangle);
vcy := 0;
vcz := -cylength*cosd(curangle);
lenvec := (vcx,vcy,vcz);
for j=1 upto numcylis:
othcoord := (j-0.5*(numcylis+1))*gridstep;
base := major*(0,1,-cosd(curangle));
base := base +(curcoord,othcoord,0);
rigorousdisc( 0, true,base,cyradius,lenvec);
endfor;
endfor;
for i=1 upto numcylis: % saddle
curnorma := i-0.5*(numcylis+1);
curcoord := curnorma*gridstep;
curangle := curnorma*anglstep;
vcx := cylength*sind(curangle);
for j=1 upto numcylis:
othcoord := (j-0.5*(numcylis+1))*gridstep;
othangle := (j-0.5*(numcylis+1))*anglstep;
vcy := -cylength*sind(othangle);
vcz := -cylength*cosd(curangle)*cosd(othangle);
base := major*(0,1,1-cosd(curangle)+cosd(othangle));
base := base + (curcoord,othcoord,0);
lenvec := (vcx,vcy,vcz);
rigorousdisc( 0, true,base,cyradius,lenvec);
endfor;
endfor;
endfig;
beginfig(2);
f := (5,3,4);
Spread := 70;
numeric gridstep, cylength, cyradius, numcylis;
numeric i, j, curcoord, curangle, curnorma;
numeric othcoord, othangle, zcoord, coef, othnorma;
color base, lenvec;
cylength := 0.1;
cyradius := 0.3;
gridstep := cyradius*2.2;
numcylis := 5;
coef := 0.32;
for i=1 upto numcylis: % splay
curnorma := i-0.5*(numcylis+1);
curcoord := curnorma*gridstep;
curangle := -curcoord*2*coef;
for j=1 upto numcylis:
othnorma := j-0.5*(numcylis+1);
othcoord := othnorma*gridstep;
othangle := -othcoord*2*coef;
zcoord := -coef*(othcoord**2+curcoord**2);
base := (curcoord,othcoord,zcoord);
lenvec := cylength*N((-curangle,-othangle,1));
rigorousdisc( 0, true,base,cyradius,lenvec);
endfor;
endfor;
endfig;
verbatimtex
\end{document}
etex
end;
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