How to fix a coordinate for a node wrt grid in Tikz picture (Tikz101)

Question

I am at Tikz 101 level so am figuring out a unified way of drawing graphics so that the all are positioned wrt to a fixed ref point in all slides in a beamer document.

To get a reference coordinate, I thought of first putting a grid on slide in beamer document. Can any one tell me how can I specify the coordinate for node b1. I am assuming that once I fix the location of first node, the rest of the blocks will not require any node reference as their position will be defined in reference to node b1. My MWE is:

\documentclass{beamer}
\usepackage{verbatim}
\usepackage{tikz}
\usepackage{text comp}
\usetikzlibrary{shapes.geometric ,arrows}

   \begin{document}
   % Definition of blocks:
   \tikzstyle{block} = [rectangle, minimum width=2cm, minimum height=1cm, text centered, text width=2cm, draw=black, fill=white]

   \begin{frame}
   \begin{center} 
   \begin{tikzpicture}[node distance=2 cm]
   \draw [step=0.5cm,gray,very thin](-5,-2) grid (5,5);
   \draw (+0,+1.5) [red] circle (0.5 cm);

   \node(b1) [block] {B1};
   \node(b2) [block, right of=b1, xshift=0.3cm] {B2};

\end{tikzpicture}
\end{center} 
\end{frame}
\end{document}

Is there a better way to achieve this ?

another TikZ 101 point: http://tex.stackexchange.com/questions/52372/should-tikzset-or-tikzstyle-be-used-to-define-tikz-styles — percusse, Mar 03 '16 at 18:11
You can position nodes using \node at (x,y) {}; but whether this is the best way depends on where you want to position the node b1. Where do you want it in respect to the page? — Alenanno, Mar 03 '16 at 18:28
I want it to be in positioned in such a way that my figure starts from top left corner of my tikzpicture. — NAASI, Mar 03 '16 at 18:31
Then maybe \node[anchor=north west] at (x,y); would be the command you need, so the top left corner of the node will be at the coordinate (x,y). — Jānis Lazovskis, Mar 03 '16 at 23:15
With [remember picture] you have access to the anchor points like (current page.center) and (current page.south east). Just interpolate to find any point on the page. — John Kormylo, Mar 04 '16 at 03:04
Since you have some responses below that seem to answer your question, please consider marking one of them as ‘Accepted’ by clicking on the tickmark below their vote count (see How do you accept an answer?). This shows which answer helped you most, and it assigns reputation points to the author of the answer (and to you!). It's part of this site's idea to identify good questions and answers through upvotes and acceptance of answers. — samcarter_is_at_topanswers.xyz, Oct 05 '17 at 22:28

score 3 · Answer 1 · answered Oct 12 '16 at 18:41

With remember picture,overlay it is possible to position FIG tikz anywhere on the page.

this requires two compalitions.

\documentclass{beamer}
\usepackage{verbatim}
\usepackage{tikz}
\usepackage{text comp}
\usetikzlibrary{shapes.geometric ,arrows}

   \begin{document}

   \begin{frame}
   \begin{center} 
   \begin{tikzpicture}[node distance=2 cm,remember picture,overlay,shift={(current page.center)}]

   \node[circle,draw](b1)at (0,0) {B1} ;
   \draw[gray] (current page.north) -- (current page.south);
      \draw[gray] (current page.east) -- (current page.west);
    \draw [step=0.5cm,gray,very thin](-.4\textwidth,0.4\textheight) grid (.4\textwidth,-0.4\textheight);

\end{tikzpicture}
\end{center} 
\end{frame}
\end{document}

How to fix a coordinate for a node wrt grid in Tikz picture (Tikz101)

1 Answers1

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