Graphics, Figures & Tables ⇒ Draw arcs on a sphere and mark the points with tikz

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Hi, I have a problem with using the package TikZ and in particular with the package TikZ-3dplots. My goal is to draw a sphere with highlighted some points, meridians, parallels, and arcs that connect the different points on the sphere. Initially I started with this example http://texample.net/tikz/examples/spher ... ian-grids/, but I found here http://www.latex-community.org/forum/vi ... 45&p=86098 that there are some bugs in the new version of TikZ that compiling the code provided do not give the same result as seen in the example. So I tried to use the package 3dplots and in this way I was able to draw the sphere, the meridians, parallels, the frame of reference, but I can not mark the points on the sphere or draw arcs between two points that are not exactly on a meridian or parallel. Searching the web I found this thread that is right for me http://tex.stackexchange.com/questions/ ... re-in-tikz, but unfortunately 3dplots combining with the code of the thread I can not find any matches on the corners for each point. What I want to achieve is something like this

but with more arches that highlight for example the angle POQ.
So I ask you if there is a quick way to put points on the sphere and draw arcs between several points on the sphere and arcs that indicate the angle between two lines generic.

I post here the code of what I have achieved so far and the image obtained. As you can see by now i made the red arc, that is neither on a meridian or parallel, by rotating the reference system and drawing on the new xy plane an arc specified (after many attempts), but it is unthinkable always do so.
Thanks in advance.

Code: Select all

\documentclass{article}
\usepackage{tikz}   
\usepackage{tikz-3dplot}

\begin{document}

%Angle Definitions
%-----------------

%set the plot display orientation
%synatax: \tdplotsetdisplay{\theta_d}{\phi_d}
\tdplotsetmaincoords{65}{110}

\pgfmathsetmacro{\rvec}{1.2}



\pgfmathsetmacro{\thetavecc}{55}
\pgfmathsetmacro{\phivecc}{35}

\pgfmathsetmacro{\thetaveccc}{39.7}
\pgfmathsetmacro{\phiveccc}{55}


\begin{tikzpicture}[scale=5,tdplot_main_coords]

\shadedraw[tdplot_screen_coords,ball color = white] (0,0) circle (\rvec);



%-----------------------
\coordinate (O) at (0,0,0);


\tdplotsetcoord{B}{\rvec}{\thetavecc}{\phivecc}

\tdplotsetcoord{C}{\rvec}{\thetaveccc}{\phiveccc}

%draw the main coordinate system axes
\draw[thick,->] (0,0,0) -- (1.7,0,0) node[anchor=north east]{$x$};
\draw[thick,->] (0,0,0) -- (0,1.7,0) node[anchor=north west]{$y$};
\draw[thick,->] (0,0,0) -- (0,0,1.7) node[anchor=south]{$z$};



\draw[-stealth,very thick,color=blue] (O) -- (B);
%

\draw[-stealth,very thick,color=green!60!black] (O) -- (C);

\draw[dashed, color=blue] (O) -- (Bxy);
\draw[dashed, color=blue] (B) -- (Bxy);


\draw[dashed, color=green!60!black] (O) -- (Cxy);
\draw[dashed, color=green!60!black] (C) -- (Cxy);





\tdplotdrawarc[color=blue]{(O)}{0.3}{0}{\phivecc}{anchor=north}{$\lambda_A$}

\tdplotsetthetaplanecoords{\phivecc}

\tdplotdrawarc[color=blue,tdplot_rotated_coords]{(0,0,0)}{0.3}{90}{\thetavecc}{anchor=south west}{$\varphi_A$}

\tdplotdrawarc[color=green!40!black]{(O)}{0.7}{0}{\phiveccc}{anchor=north}{$\lambda_B$}

\tdplotsetthetaplanecoords{\phiveccc}

\tdplotdrawarc[color=green!40!black,tdplot_rotated_coords]{(0,0,0)}{0.7}{90}{\thetaveccc}{anchor=south west}{$\varphi_B$}









\draw[dashed] (\rvec,0,0) arc (0:360:\rvec);
\draw[thick] (\rvec,0,0) arc (0:110:\rvec);
\draw[thick] (\rvec,0,0) arc (0:-70:\rvec);


\tdplotsetthetaplanecoords{35}
\draw[thick,tdplot_rotated_coords] (\rvec,0,0) arc (0:151:\rvec);
\draw[very thick,color=red,tdplot_rotated_coords] (\rvec,0,0) arc (0:55:\rvec);
\draw[dashed,tdplot_rotated_coords] (\rvec,0,0) arc (180:-40:-\rvec);
\draw[thick,tdplot_rotated_coords] (\rvec,0,0) arc (360:336:\rvec);

\tdplotsetthetaplanecoords{55}
\draw[thick,tdplot_rotated_coords] (\rvec,0,0) arc (0:147:\rvec);
\draw[very thick,color=red,tdplot_rotated_coords] (\rvec,0,0) arc (0:40:\rvec);
\draw[dashed,tdplot_rotated_coords] (\rvec,0,0) arc (180:-40:-\rvec);
\draw[thick,tdplot_rotated_coords] (\rvec,0,0) arc (360:334:\rvec);




\tdplotsetrotatedcoords{-79.1}{-120}{27.3}
\draw[very thick,color=red,tdplot_rotated_coords] (\rvec,0,0) arc (0:21:\rvec);


\end{tikzpicture}


\end{document}