Spiral cone

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\documentclass[border=10pt]{standalone}
\usepackage[inline]{asymptote}
\begin{document}
\begin{asy}
settings.render = 0;
settings.prc = false;
import graph3;
real unit = 0.1cm;
unitsize(unit);
defaultpen(fontsize(10pt));
triple eyeDirection = dir((-2,-2,0.7));
currentprojection = orthographic(eyeDirection);
triple translateDirection = dir(cross(Z, eyeDirection));
void drawBehind(path3 thepath, pen pen=currentpen, real backOpacity = 1.0, real backWidth=2.0)
{
  real newsize = backWidth;
  real distBehind = (newsize/2 + linewidth(pen)/2 + 10) * (1bp/unit);
  draw(shift(-distBehind*dir(eyeDirection))*thepath, white+linewidth(newsize)+opacity(backOpacity));
}
real r(real t) { return t; }
real z(real t) { return t; }
real theta(real t) { return t; }
triple F(real t) {
  real r = r(t);
  real z = z(t);
  real theta = theta(t);
  return (r*cos(theta), r*sin(theta), z);
}
path3 p = graph(F, 0, 7*2pi, operator ..);
drawBehind(p);
draw(p);
drawBehind((0,0,0) -- (0,0,70));
draw((0,0,0) -- (0,0,70), arrow=Arrow3());
label("$Z$", position=(0,0,70), align=W);
 
 
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Source: TeX.SE
Author: Charles Staats (License)