\documentclass[border=4pt]{standalone} \usepackage{tikz} \usetikzlibrary{angles, quotes, calc} \begin{document} \begin{tikzpicture}[line cap = round] % \draw (0,0) grid (10,10); \coordinate (Ai) at (5,3) {}; \coordinate (Bi) at (6,7) {}; \coordinate (Aj) at (4,3) {}; \coordinate (Bj) at (3,7) {}; \coordinate (P) at (4.5,2.5) {}; \node[inner sep = 0.2cm] (DVreco) at ($(P)+(1,-0.8)$) {}; \coordinate (P') at (4.5,1) {}; \node[inner sep = 0.2cm] (DVtrue) at ($(P')+(-0.6,0)$) {}; \node[inner sep = 0.2cm] (thetai) at (6,4) {}; \node[inner sep = 0.2cm] (thetaj) at (3,4) {}; \draw[very thick] (Ai) -- (Bi); \draw[thick, dashed] ($(Ai)!-0.55!(Bi)$) -- (Ai); \draw[very thick] (Aj) -- (Bj); \draw[thick, dashed] ($(Aj)!-0.55!(Bj)$) -- (Aj); \draw[dashed] (P) -- (Ai); \draw[dashed] (P) -- (Bi); \draw[dashed] (P) -- (Aj); \draw[dashed] (P) -- (Bj); \draw[fill=black] (Ai) circle (1.5pt); \draw[fill=black] (Bi) circle (1.5pt); \draw[fill=black] (Aj) circle (1.5pt); \draw[fill=black] (Bj) circle (1.5pt); \draw[fill=black] (P) circle (1.5pt); \draw[fill=black] (P) circle (1.5pt); \draw[fill=black] (P') circle (1.5pt); \pic[draw, thick, angle eccentricity=1.4, angle radius=0.6cm] {angle = Ai--P--Bi}; \pic[draw, thick, angle eccentricity=1.4, angle radius=0.6cm] {angle = Bj--P--Aj}; \node[right] at (Ai) {$\mathrm{P_i}$}; \node[right] at (Bi) {$\mathrm{P'_i}$}; \node[left] at (Aj) {$\mathrm{P_j}$}; \node[left] at (Bj) {$\mathrm{P'_j}$}; \node at (DVreco) {\scriptsize$\mathrm{DV}_\mathrm{reco}$}; \node at (DVtrue) {\scriptsize$\mathrm{DV}_\mathrm{true}$}; \node[] at (thetai) {$\theta_\mathrm{i}$}; \node[] at (thetaj) {$\theta_\mathrm{j}$}; \draw[-latex] (DVreco) to[bend right=20](P); \draw[-latex] (thetai) to[bend right=10](4.8,3); \draw[-latex] (thetaj) to[bend left=10](4.2,3); \end{tikzpicture} \end{document}