For drawing a spiral cone, we need to find an appropriate parametrization.
This code was written by Gonzalo Medina on TeX.SE.
Edit and compile if you like:\documentclass[border=5pt]{standalone} \usepackage{pgfplots} \pgfplotsset{width=7cm,compat=1.8} \usetikzlibrary{decorations.markings} \def\Point{36.9} \begin{document} \begin{tikzpicture} \begin{axis}[ view = {-25}{-25}, axis lines = middle, zmax = 60, height = 8cm, xtick = \empty, ytick = \empty, ztick = \empty ] \addplot3+ [ ytick = \empty, yticklabel = \empty, domain = 0:14.7*pi, samples = 400, samples y = 0, mark = none, thick, red, ] ( {x*sin(0.28*pi*deg(x))},{x*cos(0.28*pi*deg(x)},{x}); \addplot3+ [ mark options = {color=blue}, mark = * ] coordinates {({\Point*sin(0.28*pi*deg(\Point))}, {\Point*cos(0.28*pi*deg(\Point)}, {\Point})}; \addplot3+ [ domain = 0:12*pi, samples = 100, samples y = 0, mark = none, dashed, ] ( {\Point*sin(0.28*pi*deg(\Point))}, {\Point*cos(0.28*pi*deg(\Point)}, {x} ); \addplot3[ mark=none, dashed ] coordinates {(0,0,0) ({\Point*sin(0.28*pi*deg(\Point))}, {\Point*cos(0.28*pi*deg(\Point)}, {0})}; \draw[ radius = 80, decoration = { markings, mark= at position 0.99 with {\arrow{latex}} }, postaction=decorate ] (axis cs:0,10,0) arc[start angle=80,end angle=14] (axis cs:14,0,0); \node at (axis cs:20,0,30) {$P$}; \node at (axis cs:24,0,7) {$z$}; \node [font=\footnotesize] at (axis cs:20,17,0) {$\varrho$}; \node [font=\footnotesize] at (axis cs:6,15,0) {$\varphi$}; \end{axis} \end{tikzpicture} \end{document}
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