\begin{tikzpicture}
\filldraw [fill=white!80!cyan] (1/4,1/4)rectangle(22/4,22/4);
\coordinate (O') at (1/4,22/4);
\coordinate (A') at (1/4,1/4);
\coordinate (B') at (22/4,22/4);
\coordinate (C') at (22/8+0.125,7.6);
\coordinate (D') at (22/4,1/4);
\coordinate (E') at ($(C')+(21/4,0)$);
\coordinate (F') at ($(E')-(0,21/4)$);
\coordinate (O) at ($(O')!.5!(A')$);
\coordinate (A) at ($(D')!.5!(A')$);
\coordinate (B) at ($(O')!.5!(C')$);
\coordinate (C) at ($(C')!.5!(E')$);
\coordinate (D) at ($(F')!.5!(E')$);
\coordinate (E) at ($(F')!.5!(D')$);
% \fill (O') circle (0.03) node at (O')[left]{O'};
% \fill (A') circle (0.03) node at (A')[left]{A'};
% \fill (B') circle (0.05) node at (B')[left]{B'};
% \fill (C') circle (0.03) node at (C')[left]{C'};
% \fill (D') circle (0.03) node at (D')[left]{D'};
% \fill (E') circle (0.03) node at (E')[left]{E'};
% \fill (F') circle (0.03) node at (F')[left]{F'};
% \fill (O) circle (0.03) node at (O)[left]{O};
% \fill (A) circle (0.03) node at (A)[left]{A};
% \fill (B) circle (0.03) node at (B)[left]{B};
% \fill (C) circle (0.03) node at (C)[left]{C};
% \fill (D) circle (0.03) node at (D)[right]{D};
% \fill (E) circle (0.03) node at (E)[left]{E};
\filldraw [fill=white!50!cyan,line join=round](O')--(C')--(E')--(B')--(O');
\filldraw [fill=black!30!cyan,line join=round](B')--(D')--(F')--(E')--(B');
\draw [very thick,line join=round](O)--(A)--(E)--(D)--(C)--(B)--(O);
% 正面
\foreach \y in {1,2,...,21}{
\foreach \x in {1,2,...,21}
{
\draw (\x/4,\y/4) rectangle ++(0.25,0.25);
}
}
% 上
\foreach \y in {0,1,2,...,20}{
\foreach \x in {1,2,...,20,21}
{
\draw [line join=round](\x/4+\y/8,\y/10+5.5)--++(0.25,0)--++(0.125,0.1)--++(-0.25,0)--++(-0.125,-0.1)--cycle;
}
}
% 横
\foreach \y in {0,1,2,...,20}{
\foreach \x in {0,1,2,...,20}
{
\draw [line join=round](\x/8+5.5,\x/10+\y/4+0.25)--++(0.125,0.1)--++(0,0.25)--++(-0.125,-0.1)--++(0,-0.25)--cycle;
}
}
\end{tikzpicture}
\begin{tikzpicture}
\filldraw [fill=white!80!cyan] (1/4,1/4)rectangle(22/4,22/4);
\coordinate (O') at (1/4,22/4);
\coordinate (A') at (1/4,1/4);
\coordinate (B') at (22/4,22/4);
\coordinate (C') at (22/8+0.125,7.6);
\coordinate (D') at (22/4,1/4);
\coordinate (E') at ($(C')+(21/4,0)$);
\coordinate (F') at ($(E')-(0,21/4)$);
\coordinate (O) at ($(O')!.5!(A')$);
\coordinate (A) at ($(D')!.5!(A')$);
\coordinate (B) at ($(O')!.5!(C')$);
\coordinate (C) at ($(C')!.5!(E')$);
\coordinate (D) at ($(F')!.5!(E')$);
\coordinate (E) at ($(F')!.5!(D')$);
% \fill (O') circle (0.03) node at (O')[left]{O'};
% \fill (A') circle (0.03) node at (A')[left]{A'};
% \fill (B') circle (0.05) node at (B')[left]{B'};
% \fill (C') circle (0.03) node at (C')[left]{C'};
% \fill (D') circle (0.03) node at (D')[left]{D'};
% \fill (E') circle (0.03) node at (E')[left]{E'};
% \fill (F') circle (0.03) node at (F')[left]{F'};
% \fill (O) circle (0.03) node at (O)[left]{O};
% \fill (A) circle (0.03) node at (A)[left]{A};
% \fill (B) circle (0.03) node at (B)[left]{B};
% \fill (C) circle (0.03) node at (C)[left]{C};
% \fill (D) circle (0.03) node at (D)[right]{D};
% \fill (E) circle (0.03) node at (E)[left]{E};
\filldraw [fill=white!50!cyan,line join=round](O')--(C')--(E')--(B')--(O');
\filldraw [fill=black!30!cyan,line join=round](B')--(D')--(F')--(E')--(B');
% 正面
\foreach \y in {1,2,...,21}{
\foreach \x in {1,2,...,21}
{
\draw (\x/4,\y/4) rectangle ++(0.25,0.25);
}
}
% 上
\foreach \y in {0,1,2,...,20}{
\foreach \x in {1,2,...,20,21}
{
\draw [line join=round](\x/4+\y/8,\y/10+5.5)--++(0.25,0)--++(0.125,0.1)--++(-0.25,0)--++(-0.125,-0.1)--cycle;
}
}
% 横
\foreach \y in {0,1,2,...,20}{
\foreach \x in {0,1,2,...,20}
{
\draw [line join=round](\x/8+5.5,\x/10+\y/4+0.25)--++(0.125,0.1)--++(0,0.25)--++(-0.125,-0.1)--++(0,-0.25)--cycle;
}
}
\filldraw[dashed,fill=white,line join=round](A)--(E)--(D')--cycle;
\filldraw[dashed,fill=white,line join=round](B)--(O)--(O')--cycle;
\filldraw[dashed,fill=white,line join=round](D)--(C)--(E')--cycle;
\filldraw [fill=orange!50!white,very thick,line join=round](O)--(A)--(E)--(D)--(C)--(B)--(O)--cycle;
\draw [dashed](O')--(B')--(D');
\draw [dashed](E')--(B');
\end{tikzpicture}