Fill surface in tikz

I know this question has already been asked a couple times in a similar way to mine. However, I can't figure out, what I am doing wrong. I want to color this quadrilateral.

\begin{tikzpicture}
\draw (3,-.5) to [<-, bend right=10] (1.5,0) node[left]{};
\draw (2,-1) to [<-, bend left=10] (.5,-.8) node[left]{};
\draw[dashed] (2,-1) -- (3,-.5) node[left] {};
\draw (.5,-.8) to (1.5,0) node[left]{};
\end{tikzpicture}


You might have to include some of the following in order to compile it.

\usepackage{tikz}
\usepackage{tkz-euclide}
\usetkzobj{all}
\usepackage{verbatim}
\usetikzlibrary{intersections}
\usepackage{pgfplots}
\usepgfplotslibrary{fillbetween}
\usetikzlibrary{backgrounds}


I found a site which used this code to color a triangle.

\def\KurveI{(3,-.5) to (1.5,0)}
\def\KurveII{(.5,-.8) to (1.5,0)}
\def\KurveIII
{(.5,-.8) to (3,-.5)}
\draw \KurveI \KurveII \KurveIII
(current path bounding box.south west)coordinate(UL)
(current path bounding box.north east)coordinate(OR);
\begin{scope}[on background layer]
\clip (UL)--\KurveI--(UL-|OR)--cycle;% Fläche unterhalb der 1.Kurve
\clip (UL-|OR)--\KurveII--(OR)--cycle;% Fläche rechts von 2.Kurve
\clip (UL|-OR)--\KurveIII--(OR)--cycle;% Fläche oberhalb von 3.Kurve
\fill[yellow!50](UL)rectangle(OR);% Füllen der Schnittfläche
\end{scope}


However, when I copy it, it only colors part of my triangle. Is there a site, where it is explained how to color surfaces with tikz? Or what am I doing wrong?

Here is some Code that should compile.

\documentclass[12pt]{article}
\usepackage[ngerman]{babel}
\usepackage{tikz}

\usetikzlibrary{intersections}
\usepackage{pgfplots}
\usepgfplotslibrary{fillbetween}
\usetikzlibrary{backgrounds}

\begin{document}

\begin{tikzpicture}
\draw (3,-.5) to [<-, bend right=10] (1.5,0);
\draw (2,-1) to [<-, bend left=10] (.5,-.8);
\draw[dashed] (2,-1) -- (3,-.5) ;
\draw (.5,-.8) to (1.5,0);
\end{tikzpicture}

\begin{tikzpicture}
\def\KurveI{(3,-.5) to (1.5,0)}
\def\KurveII{(.5,-.8) to (1.5,0)}
\def\KurveIII
{(.5,-.8) to (3,-.5)}
\draw \KurveI \KurveII \KurveIII
(current path bounding box.south west)coordinate(UL)
(current path bounding box.north east)coordinate(OR);
\begin{scope}[on background layer]
\clip (UL)--\KurveI--(UL-|OR)--cycle;
\clip (UL-|OR)--\KurveII--(OR)--cycle;
\clip (UL|-OR)--\KurveIII--(OR)--cycle;
\fill[yellow!50](UL)rectangle(OR);
\end{scope}
\end{tikzpicture}

\end{document}

• Welcome to TeX.SX! Could you please make a compilable example that shows the issue? Commented Feb 24, 2018 at 16:43
• I edited it, it should compile now. Commented Feb 24, 2018 at 16:51
• please merge your code snippets in one small complete document! help us to help you! package tikz has manual, where are described all aspect of its use in detail. Commented Feb 24, 2018 at 17:03
• What is the purpose of all the node[left]{} statements?
– user121799
Commented Feb 24, 2018 at 17:14
• The node[left]{} statements are not important here, I will use them later for adding formulas. Commented Feb 24, 2018 at 17:28

Just to approach an answer, I show you how you may fill the shape.

\documentclass[tikz]{standalone}
\begin{document}
\begin{tikzpicture}
\fill[blue] (1.5,0) to[bend left=10]  (3,-.5)  to (2,-1)  to [bend left=10]  (.5,-.8) to cycle;
\draw (3,-.5) to [<-, bend right=10] (1.5,0) node[left]{};
\draw (2,-1) to [<-, bend left=10] (.5,-.8) node[left]{};
\draw[dashed] (2,-1) -- (3,-.5) node[left] {};
\draw (.5,-.8) to (1.5,0) node[left]{};
\end{tikzpicture}
\end{document}

• Thank you, this fill command is exactly what I was looking for. Commented Feb 24, 2018 at 17:52