Fixe some typos.

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Ron Wein 2006-08-21 06:49:56 +00:00
parent 4774049577
commit 36277d973b
1 changed files with 8 additions and 8 deletions

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@ -2,7 +2,7 @@
\section{Introduction}
\label{mink_sec:intro}
% ====================
Given two sets $A,B \in \mathbb{R}^d$, their \emph{Minkowski sum},
denoted by $A \oplus B$, is the set $\left\{ a + b ~|~ a \in
A, b \in B \right\}$. Minkowski sum are used in many applications,
@ -59,7 +59,7 @@ approaches:
\item[Decomposition:]
We decompose $P$ and $Q$ into convex sub-polygons, namely we obtain two
sets of convex polygons $P_1, \ldots, P_k$ and $Q_1, \ldots, Q_\ell$ such
that $\bigcup_{i = 1}{k}{P_i} = P$ and $\bigcup_{i = j}{\ell}{Q_j} = Q$.
that $\bigcup_{i = 1}^{k}{P_i} = P$ and $\bigcup_{i = j}^{\ell}{Q_j} = Q$.
We then calculate the pairwise sums $S_{ij} = P_i \oplus Q_j$ using the
simple procedure described above, and compute the union $P \oplus Q =
\bigcup_{ij}{S_{ij}}$.
@ -78,16 +78,16 @@ boundaries. The {\em convolution} of these two polygons~\cite{grs-kfcg-83},
denoted $P * Q$, is a collection of line segments of the form
$[p_i + q_j, p_{i+1} + q_j]$,\footnote{Throughout this chapter, we increment
or decrement an index of a vertex modulo the size of the polygon.}
where the vector ${\mathbf p_i p_{i+1}}$
lies between ${\mathbf q_{j-1} q_j}$ and ${\mathbf q_j
q_{j+1}}$,\footnote{We say that a vector ${\mathbf v}$ lies between
where the vector ${\mathbf{p_i p_{i+1}}}$
lies between ${\mathbf{q_{j-1} q_j}}$ and ${\mathbf{q_j
q_{j+1}}}$,\footnote{We say that a vector ${\mathbf v}$ lies between
two vectors ${\mathbf u}$ and ${\mathbf w}$ if we reach ${\mathbf v}$ strictly
before reaching ${\mathbf w}$ if we move all three vectors to the origin
and rotate ${\mathbf u}$ counterclockwise. Note that this also covers
the case where ${\mathbf u}$ has the same direction as ${\mathbf v}$.} and
--- symmetrically --- of segments of the form $[p_i + q_j, p_i + q_{j+1}]$,
where the vector ${\mathbf q_j q_{j+1}}$ lies between
${\mathbf p_{i-1} p_i}$ and ${\mathbf p_i p_{i+1}}$.
where the vector ${\mathbf{q_j q_{j+1}}}$ lies between
${\mathbf{p_{i-1} p_i}}$ and ${\mathbf{p_i p_{i+1}}}$.
The segments of the convolution form a number of closed (not
necessarily simple) polygonal curves called \emph{convolution
@ -387,7 +387,7 @@ $p_1 p_2$ by a vector whose length is $r$ that form an angle $\phi$ with the
$x$-axis. We select two points $o'_1$ and $o'_2$ with rational coordinates
on the two circles centered at $p_1$ and $p_2$, respectively. These points
are selected such that if we denote the angle that the vector
${\mathbf p_j o_j}$
${\mathbf{p_j o_j}}$
forms with the $x$-axis by $\phi'_j$ (for $j = 1, 2$), we have
$\phi'_1 < \phi < \phi'_2$.
%