Ykhjuy

I am trying to draw a diagram that looks approximately like this:

The red boxes are the items I would like to add to the diagram. They represent spectra lines that can be generated using the pgf-spectra package (https://ctan.org/pkg/pgf-spectra?lang=en). When I try to use a scope to move the box like in my not working example below, the spectra box is not moved. I was wondering if it were possible to move the spectra boxes at all, either in the document or by changing code in the package .sty files

My MNWE:

documentclass{standalone}

usepackage{tikz}

usepackage{pgf-spectra}

usetikzlibrary{decorations.pathmorphing}

tikzset{snake it/.style={decorate, decoration=snake}}

begin{document}

    begin{tikzpicture}

    draw[-latex] (0,0) ++ (60:1.5) arc (60:120:1.5);

    draw[-latex] (0,0) ++ (-120:1.5) arc (-120:-60:1.5);

    draw[snake it,blue,-latex,thick] (0,1) -- (-4,1);

    draw[snake it,red,-latex,thick] (0,-1) -- (-4,-1);

    draw[snake it,-latex,thick] (-1,0) -- (-4,0);

    draw[fill=yellow!50] (0,0) circle (1);

% -- this part below is what I want to move but it does not behave correctly

    begin{scope}{xshift=-4cm,yshift=1cm}

        pgfspectra[width=5cm]

    end{scope}

end{tikzpicture}

end{document}

Here is the output it renders:

WARNING: This is a workaround for a simple use case. It does not provide any of the complex options the package will offer. If you wanted these, the package would need to be fixed.

With a bit of reverse engineering you can get something like the following. It copies some internal parts from pgf-spectra to avoid nesting tikzpictures which are preventing your scope from shifting. You may still set width and height keys.

documentclass{article}

usepackage{tikz}

usepackage{pgf-spectra}

usetikzlibrary{decorations.pathmorphing}

tikzset{snake it/.style={decorate, decoration=snake}}

begin{document}

    begin{tikzpicture}

    draw[-latex] (0,0) ++ (60:1.5) arc (60:120:1.5);

    draw[-latex] (0,0) ++ (-120:1.5) arc (-120:-60:1.5);

    draw[snake it,blue,-latex,thick] (0,1) -- (-4,1);

    draw[snake it,red,-latex,thick] (0,-1) -- (-4,-1);

    draw[snake it,-latex,thick] (-1,0) -- (-4,0);

    draw[fill=yellow!50] (0,0) circle (1);

        makeatletter

    begin{scope}[shift={(-10cm,.5cm)}]

      % adapted from pgf-spectra.sty

      pgfkeys{/wl/.cd,width=5cm,height=1cm}

      foreach x in {380,...,780}%

        {%

        pgfmathparse{wlwidth/(abs(wlend-wlbegin))}edefxscale{pgfmathresult}

        edefwl@linewidth{xscale pt}

        wlcolor{x}%

        pgfmathparse{(x-380)*xscale}edefwl@currentx{pgfmathresult pt}%

        draw[wltemp,line width=wl@linewidth] (wl@currentx,0) -- ++(0,wlheight);%

        }%

    end{scope}

    makeatother

end{tikzpicture}

end{document}

I have made a workaround using TeXnician's suggestions:

documentclass{article}

usepackage{tikz}

usepackage{pgf-spectra}

usetikzlibrary{decorations.pathmorphing}

tikzset{snake it/.style={decorate, decoration=snake}}

begin{document}

    setlength{unitlength}{1cm}

    thicklines

    begin{picture}(0,0)

    put(-5,2.5) {parbox{4cm}{pgfspectra[lines={390,490,540,690},absorption,height=0.5cm,width=5cm]}}

    put(-5,2) {parbox{4cm}{pgfspectra[lines={395,495,545,695},absorption,height=0.5cm,width=5cm]}}

    put(-5,1.5) {parbox{4cm}{pgfspectra[lines={400,500,550,700},absorption,height=0.5cm,width=5cm]}}

    put(-5,1) {parbox{4cm}{pgfspectra[lines={405,505,555,705},absorption,height=0.5cm,width=5cm]}}

    put(-5,0.5) {parbox{4cm}{pgfspectra[lines={410,510,560,710},absorption,height=0.5cm,width=5cm]}}

    put(-5,-0.5) {parbox{14cm}{pgfspectra[lines={400,500,550,700},absorption,height=0.5cm,width=5cm,line width=4pt]}}

    end{picture}

    begin{tikzpicture}

    draw[-latex] (0,0) ++ (60:1.5) arc (60:120:1.5);

    draw[-latex] (0,0) ++ (-120:1.5) arc (-120:-60:1.5);

    draw[snake it,blue,-latex,thick] (0,1) -- (-4,1);

    draw[snake it,red,-latex,thick] (0,-1) -- (-4,-1);

    draw[snake it,-latex,thick] (-1,0) -- (-4,0);

    draw[fill=yellow!50] (0,0) circle (1);

    end{tikzpicture}

    tikz[overlay,remember picture]{node at (-2.8,-0.5) {Widening of absorption lines};}

end{document}