Drawing a parallelopiped in TikZ

Question

I need to draw a parallelopiped like this in TikZ:

I want to draw in 3D using views and not in 2D.

Answer 1

TikZ is internally 2D, so you can only draw one 2D projection on the screen plane of the oblique cuboid; some packages like tikz3d-plot, 3dtool or the library perspective may be used.

In case of real 3D Asymptote, you can copy the following code to http://asymptote.ualberta.ca/ click Run, then use the computer mouse to rotate the output figure. You can guess the meaning of the numbers in the 3-dim transform ty for slanting along y-axis; the last column in the matrix is always $(0,0,0,1)^T$.

// http://asymptote.ualberta.ca/
size(4cm);
import three;
// slanting along y-axis
transform3 ty={
{ 1, 0,  0, 0},
{ 0, 1, .4, 0},
{ 0, 0,  1, 0},
{ 0, 0,  0, 1}
};
draw(tyunitcube,yellow+opacity(.5));
draw(tyunitbox,purple+opacity(1));

Answer 2

Try this:

\documentclass[tikz,border=3.14mm]{standalone}
\begin{document}
    \begin{tikzpicture}
    \draw[fill=cyan] (0,0)--(4,0)--(5,3)--(1,3)--(0,0);
    \draw[fill=green] (5,3)--(1,3)--(2,4)--(6,4)--(5,3);
    \draw[fill=yellow] (4,0)--(5,3)--(6,4)--(5,1)--(4,0);       
    \draw[dashed] (2,4)--(1,1);
    \draw[dashed] (0,0)--(1,1);
    \draw[dashed] (1,1)--(5,1);

\end{tikzpicture}

\end{document}

Output: