beamer/tikz 覆盖图像在中心

Question

我怎样才能在 tikz 中将图像叠加在幻灯片的中心并覆盖文本。

考虑：

\documentclass{beamer}
\usepackage{tikz}
\usepackage{lipsum}
\begin{document}

\begin{frame}

\lipsum[1]

\begin{tikzpicture}[overlay]
  \pause
  \node (img1) {\rule{3cm}{2cm}};
  \pause
  \node (img2) at (img1.south east) {\rule{3cm}{2cm}};
  \pause
  \node (img3) at (img2.south west) [yshift=1cm] {\rule{3cm}{2cm}};
\end{tikzpicture}
\end{frame}

\end{document}

我希望图像动画出现在幻灯片的中央。

奖励积分如果您可以用灰色覆盖整个幻灯片来突出显示图像。

Answer 1

像这样？我使用了current page.节点系列（我使用了一些不透明度；根据您的需要调整设置）：

代码：

\documentclass{beamer}
\usepackage{tikz}
\usepackage{lipsum}

\begin{document}

\begin{frame}
\lipsum[1]

\begin{tikzpicture}[remember picture,overlay]
  \pause
  \fill[gray!80,opacity=0.8]
  (current page.north west) rectangle (current page.south east);
  \pause
  \node (img1) at (current page.center) {\includegraphics[width=3cm,height=2cm]{example-grid-100x100pt}};
  \pause
  \node (img2) at (img1.south east) {\includegraphics[width=3cm,height=2cm]{example-grid-100x100pt}};
  \pause
  \node (img3) at (img2.south west) [yshift=1cm] {\includegraphics[width=3cm,height=2cm]{example-grid-100x100pt}};
\end{tikzpicture}
\end{frame}

\end{document}