Cfrgtkky

This is a a curved cube

begin{tikzpicture}[thick,scale=3]

coordinate (A1) at (0, 0);

coordinate (A2) at (0, 1);

coordinate (A3) at (1, 1);

coordinate (A4) at (1, 0);

coordinate (B1) at (0.3, 0.3);

coordinate (B2) at (0.3, 1.3);

coordinate (B3) at (1.3, 1.3);

coordinate (B4) at (1.3, 0.3);

coordinate (C1) at (0.4, 2);

coordinate (C2) at (2, -0.4);

coordinate (C3) at (1, .6);

coordinate (C4) at (2, 0.7);

coordinate (C5) at (1, 1.6);

coordinate (C6) at (2, 0.6);

coordinate (C7) at (2, 0.1);

coordinate (C8) at (2, 1.6);

coordinate (C9) at (2, 1.1);

coordinate (C10) at (.8, 2.2);

coordinate (C11) at (1.3, 2);

coordinate (C12) at (1.6, 2);

draw[draw=black, line width=.5mm] plot [smooth, tension=1] coordinates {(A1) (A2) (C1)};

draw[draw=black, line width=.5mm] plot [smooth, tension=1] coordinates {(A1) (A4) (C2)};

draw[draw=black, line width=.5mm] plot [smooth, tension=1] coordinates {(A1) (B1) (C3)};

draw[draw=black] plot [smooth, tension=1] coordinates {(A2) (A3) (C4)};

draw[draw=black] plot [smooth, tension=1] coordinates {(A2) (B2) (C5)};

draw[draw=black] plot [smooth, tension=1] coordinates {(A4) (B4) (C6)};

draw[draw=black] plot [smooth, tension=1] coordinates {(B1) (B4) (C7)};

draw[draw=black] plot [smooth, tension=1] coordinates {(A3) (B3) (C8)};

draw[draw=black] plot [smooth, tension=1] coordinates {(B2) (B3) (C9)};

draw[draw=black] plot [smooth, tension=1] coordinates {(B1) (B2) (C10)};

draw[draw=black] plot [smooth, tension=1] coordinates {(A4) (A3) (C11)};

draw[draw=black] plot [smooth, tension=1] coordinates {(B4) (B3) (C12)};

draw[fill=blue] (0,0) circle [radius=.02cm];

draw[fill=blue] (0,1) circle [radius=.02cm];

draw[fill=blue] (1,0) circle [radius=.02cm];

draw[fill=blue] (.3,.3) circle [radius=.02cm];

draw[fill=blue] (1.3,.3) circle [radius=.02cm];

draw[fill=blue] (.3,1.3) circle [radius=.02cm];

draw[fill=blue] (1,1) circle [radius=.02cm];

draw[fill=blue] (1.3,1.3) circle [radius=.02cm];

node[black] at (-.2,0) {$M_0$};

node[black] at (1,-.2) {$M_1$};

node[black] at (.15,.35) {$M_2$};

node[black] at (-.2,1) {$M_3$};

node[black] at (1.4,.5) {$M_{12}$};

node[black] at (.6,1.6) {$M_{32}$};

node[black] at (.85,1.1) {$M_{31}$};

node[black] at (1.45,1.5) {$N$};

node[black] at (1.45,-.3) {$q_1$-linha};

node[black] at (.7,.6) {$q_2$-linha};

node[black] at (0,2) {$q_3$-linha};

end{tikzpicture}

How to fill faces with different colors?

In general, you can recover parts of a path using pgfplots (!) library fillbetween, and these parts can be used to fill some area they are confining. Your example is special in that you have the coordinates of the vertices explicitly. So you can store the subpaths using show path construction. The following MWE does that in the following way:

1. If you add record path construction, the subpaths (and their reversed versions) will be stored in a list.


2. You can redraw the subpaths or combine them to form a boundary of a face.

Unfortunately I find the names of your coordinates not too easy to interpret, but you will find it of course easier. For example,

 fill[red,opacity=0.3,scale=1/3,redraw segments={1,4,40,13}] ;

The numbers here depend on the order in which you draw the paths.

documentclass[tikz,border=3.14mm]{standalone}

usetikzlibrary{decorations.pathreplacing,backgrounds}

newcounter{segments}

tikzset{record path construction/.style={decoration={show path construction,

 curveto code={stepcounter{segments}stepcounter{segments}

 ifdefinedLstSegments

 xdefLstSegments{LstSegments,

 "(tikzinputsegmentfirst) .. controls

        (tikzinputsegmentsupporta) and (tikzinputsegmentsupportb)

        ..(tikzinputsegmentlast)","(tikzinputsegmentlast) .. controls

        (tikzinputsegmentsupportb) and (tikzinputsegmentsupporta)

        ..(tikzinputsegmentfirst)"}

 else

 xdefLstSegments{"(tikzinputsegmentfirst) .. controls

        (tikzinputsegmentsupporta) and (tikzinputsegmentsupportb)

        ..(tikzinputsegmentlast)","(tikzinputsegmentlast) .. controls

        (tikzinputsegmentsupportb) and (tikzinputsegmentsupporta)

        ..(tikzinputsegmentfirst)"}

 fi        

    }},postaction=decorate},

 reconstruct segment/.style={/utils/exec=pgfmathsetmacro{mysegment}{{LstSegments}[#1]},

 insert path=mysegment},

 redraw segments/.style={/utils/exec={foreach Segment [count=nSeg] in {#1}

 {pgfmathsetmacro{mysegment}{{LstSegments}[Segment]}

 ifnumnSeg=1

 xdefmysegments{mysegment}

 else

 xdefmysegments{mysegments -- mysegment}

 fi}},

 insert path=mysegments},% 

 }

begin{document}

begin{tikzpicture}[thick,scale=3]

coordinate (A1) at (0, 0);

coordinate (A2) at (0, 1);

coordinate (A3) at (1, 1);

coordinate (A4) at (1, 0);

coordinate (B1) at (0.3, 0.3);

coordinate (B2) at (0.3, 1.3);

coordinate (B3) at (1.3, 1.3);

coordinate (B4) at (1.3, 0.3);

coordinate (C1) at (0.4, 2);

coordinate (C2) at (2, -0.4);

coordinate (C3) at (1, .6);

coordinate (C4) at (2, 0.7);

coordinate (C5) at (1, 1.6);

coordinate (C6) at (2, 0.6);

coordinate (C7) at (2, 0.1);

coordinate (C8) at (2, 1.6);

coordinate (C9) at (2, 1.1);

coordinate (C10) at (.8, 2.2);

coordinate (C11) at (1.3, 2);

coordinate (C12) at (1.6, 2);

draw[draw=black, line width=.5mm,record path construction] plot [smooth, tension=1] coordinates {(A1) (A2) (C1)};

draw[draw=black, line width=.5mm,record path construction] plot [smooth, tension=1] coordinates {(A1) (A4) (C2)};

draw[draw=black, line width=.5mm,record path construction] plot [smooth, tension=1] coordinates {(A1) (B1) (C3)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(A2) (A3) (C4)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(A2) (B2) (C5)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(A4) (B4) (C6)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(B1) (B4) (C7)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(A3) (B3) (C8)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(B2) (B3) (C9)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(B1) (B2) (C10)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(A4) (A3) (C11)};

draw[draw=black,record path construction] plot [smooth, tension=1] coordinates {(B4) (B3) (C12)};

begin{scope}[on background layer]

 fill[red,opacity=0.3,scale=1/3,redraw segments={8,36,17,1}];

 fill[green!70!black,opacity=0.3,scale=1/3,redraw segments={12,28,33,16}];

 fill[cyan,opacity=0.3,scale=1/3,redraw segments={44,33,37,24}];

 fill[orange,opacity=0.3,scale=1/3,redraw segments={20,44,29,41}]; 

 fill[blue,opacity=0.3,scale=1/3,redraw segments={1,4,40,13}];

end{scope}

% test a single segment with direction

% draw[red,thick,scale=1/3,reconstruct segment/.list={40},-latex];

% get all segments with orientation

%pgfmathruncatemacro{Ymax}{value{segments}-1}

% foreach X [count=Y starting from 0] in {1,...,value{segments}}

% {ifoddY

% else

% draw[red,thick,scale=1/3,reconstruct segment/.list={Y},-latex]

% node[midway,fill=white]{Y};

% fi}

draw[fill=blue] (0,0) circle [radius=.02cm];

draw[fill=blue] (0,1) circle [radius=.02cm];

draw[fill=blue] (1,0) circle [radius=.02cm];

draw[fill=blue] (.3,.3) circle [radius=.02cm];

draw[fill=blue] (1.3,.3) circle [radius=.02cm];

draw[fill=blue] (.3,1.3) circle [radius=.02cm];

draw[fill=blue] (1,1) circle [radius=.02cm];

draw[fill=blue] (1.3,1.3) circle [radius=.02cm];

node[black] at (-.2,0) {$M_0$};

node[black] at (1,-.2) {$M_1$};

node[black] at (.15,.35) {$M_2$};

node[black] at (-.2,1) {$M_3$};

node[black] at (1.4,.5) {$M_{12}$};

node[black] at (.6,1.6) {$M_{32}$};

node[black] at (.85,1.1) {$M_{31}$};

node[black] at (1.45,1.5) {$N$};

node[black] at (1.45,-.3) {$q_1$-linha};

node[black] at (.7,.6) {$q_2$-linha};

node[black] at (0,2) {$q_3$-linha};

end{tikzpicture}

end{document}

Figuring all the subpaths is possible but may require some patience. If you want, say, to know what segment number 40 is, do

draw[red,thick,scale=1/3,reconstruct segment/.list={40},-latex];

The arrow indicates the direction. The path number 41 will run through the same curve but in opposite direction. If you want to get a survey of all segments, uncomment

foreach X [count=Y starting from 0] in {1,...,value{segments}}

{ifoddY

else

draw[red,thick,scale=1/3,reconstruct segment/.list={Y},-latex]

node[midway,fill=white]{Y};

fi}

Notice that the way to record the paths and label/number them is not unique, there might be better ways.