handouts/Advanced/Retrograde Analysis/parts/01 intro.tex

\section{Introduction}

To solve the problems in this handout, you mustn't be a chess master---you just need to know how the pieces move.
I'd expect that you're all familiar with the basic rules of chess (ask questions if you aren't!).
The odd ones are listed below.

\generic{Board orientation:}
The bottom-left square of a chessboard is \textit{always} black.

\generic{Starting pawns \& en passant:}
A pawn may move two squares on its first turn. \par
An opposing pawn may capture this pawn as it completes this move. \par
This is called an \textit{en passant} capture (Which means \say{in passing} in French)

\begin{minipage}{0.3\textwidth}
	\begin{center}
		\chessboard[
			smallboard,
			maxfield=b4,
			setpieces = {
				pa4,pb3,
				Pa1,Pb1
			},
			addpgf={
				\tikz[overlay]
				\draw[ocyan,line width=0.1em,->]
				(a1)--(a3);
			},
		]

		White moves two squares
	\end{center}
\end{minipage}
\hfill
\begin{minipage}{0.3\textwidth}
	\begin{center}
		\chessboard[
			smallboard,
			maxfield=b4,
			setpieces = {
				pa4,pb3,
				Pa3,Pb1
			},
			addpgf={
				\tikz[overlay]
				\draw[ocyan,line width=0.1em,->]
				(b3)--(a2);
			},
		]

		Black captures en passant
	\end{center}
\end{minipage}
\hfill
\begin{minipage}{0.3\textwidth}
	\begin{center}
		\chessboard[
			smallboard,
			maxfield=b4,
			setpieces = {
				pa4,pa2,
				Pb1
			},
		]

		Result
	\end{center}
\end{minipage}

\vfill

\generic{Promotion:}
When a pawn reaches the last row of the board, it may be promoted to any other piece.\par
(Except a king or a pawn, of course.)

\generic{Castling:}
A king and rook can \textit{castle} under the following conditions:
\begin{itemize}
	\item No pieces are in the way
	\item The king has not yet moved
	\item The rook has not yet moved
	\item The king is not in check
	\item The king does not move through check while castling
\end{itemize}

\begin{minipage}{0.3\textwidth}
	\begin{center}
		\chessboard[
			smallboard,
			maxfield=h2,
			setpieces = {
				Ra1,Ke1,Rh1
			},
			addpgf={
				\tikz[overlay]
				\draw[ocyan,line width=0.1em,->]
				(e1)--(g1);
				\tikz[overlay]
				\draw[ocyan,line width=0.1em,->]
				(e1)--(c1);
			},
			hmarginwidth=0mm
		]

		Possible castle directions
	\end{center}
\end{minipage}
\hfill
\begin{minipage}{0.3\textwidth}
	\begin{center}
		\chessboard[
			smallboard,
			maxfield=h2,
			setpieces = {
				Rd1,Kc1,Rh1
			},
			hmarginwidth=0mm
		]

		Queenside castle result
	\end{center}
\end{minipage}
\hfill
\begin{minipage}{0.3\textwidth}
	\begin{center}
		\chessboard[
			smallboard,
			maxfield=h2,
			setpieces = {
				Ra1,Kg1,Rf1
			},
			hmarginwidth=0mm,
			]

		Kingside castle result
	\end{center}
\end{minipage}
\par

\vfill

\generic{General Strategies:}
As you solve problems, keep the following in mind. \par
You may want to return to this list if you get stuck.

\begin{itemize}
	\item What was the last move? (By black or white)

	\item Were there any promotions? The implication may be indirect: \par
	if White needs a third bishop, there was a promotion. \par
	\note{Promotions often resolve seemingly impossible situations.}

	\item Do not assume that Black and White play well.
	You may only assume they play \textit{correctly}.
\end{itemize}

\vfill
\pagebreak