Anonymous 1123
I am trying to draw Intersection of a sphere and a cylinder. I only tried one case
```
\documentclass[border=2mm,12pt,tikz]{standalone}
\usepackage{tikz-3dplot}
\usetikzlibrary{3d,calc,backgrounds,patterns}
\usepackage{fouriernc}
\begin{document}
\def\myr{1.5}
\def\h{6*\myr}
\def\angA{0}
\def\angB{110}
\tdplotsetmaincoords{70}{70}
\begin{tikzpicture}[tdplot_main_coords]
\begin{scope}[canvas is xy plane at z=0]
\draw[dashed] (\tdplotmainphi:\myr) arc(\tdplotmainphi:\tdplotmainphi+180:\myr);
\coordinate (O) at (0,0);
\coordinate (A) at (\angA:\myr);
\coordinate (B) at (\angB:\myr);
\coordinate (M) at ($(A)!0.5!(B)$);
\draw[thick] (\tdplotmainphi:\myr) coordinate(BR) arc(\tdplotmainphi:\tdplotmainphi-180:\myr)
coordinate(BL);
%\draw[dashed] (BL) -- (BR);
\end{scope}
%
\begin{scope}[canvas is xy plane at z=\h/3]
\coordinate (O_1) at (0,0);
\end{scope}
\begin{scope}[canvas is xy plane at z=2/3*\h]
\coordinate (O_2) at (0,0);
\end{scope}
\begin{scope}[canvas is xy plane at z=\h]
\coordinate (O') at (0,0);
\coordinate (A') at (\angA:\myr);
\coordinate (B') at (\angB:\myr);
\coordinate (M') at ($(A')!0.5!(B')$);
\draw[thick] (O') circle[radius=\myr];
\draw[dashed] (O) -- (O');
\draw [thick](BR) -- (\tdplotmainphi:\myr) (BL) -- (\tdplotmainphi-180:\myr);
\end{scope}
\coordinate (T) at ($ (O) !0.5! (O_1) $);
\coordinate (T1) at ($ (O_1) !0.5! (O_2) $);
\coordinate (T2) at ($ (O_2) !0.5! (O') $);
\foreach \v/\position in {O/below,O'/above} {\draw[draw =black, fill=black] (\v) circle (1pt) node [\position=0.2mm] {$\v$};
}
\begin{scope}[tdplot_screen_coords, on background layer]
\fill[ball color=orange!90, opacity=1.0] (T) circle (\myr);
\end{scope}
\begin{scope}[tdplot_screen_coords, on background layer]
\fill[ball color=green!90, opacity=1.0] (T1) circle (\myr);
\end{scope}
\begin{scope}[tdplot_screen_coords, on background layer]
\fill[ball color=blue!90, opacity=1.0] (T2) circle (\myr); % 3D
\end{scope}
\end{tikzpicture}
\end{document}
```
Orther cases I cannot draw. How can I draw all caces like [here](http://www.grad.hr/geomteh3d/prodori/prodor_sf_eng.html)