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diff --git a/libs/geometry/doc/html/geometry/spatial_indexes/queries.html b/libs/geometry/doc/html/geometry/spatial_indexes/queries.html new file mode 100644 index 000000000..677afcbb8 --- /dev/null +++ b/libs/geometry/doc/html/geometry/spatial_indexes/queries.html @@ -0,0 +1,412 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Queries</title> +<link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> +<link rel="home" href="../../index.html" title="Chapter 1. Geometry"> +<link rel="up" href="../spatial_indexes.html" title="Spatial Indexes"> +<link rel="prev" href="creation_and_modification.html" title="Creation and Modification"> +<link rel="next" href="rtree_examples.html" title="Examples"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table cellpadding="2" width="100%"><tr> +<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td> +<td align="center"><a href="../../../../../../index.html">Home</a></td> +<td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td> +<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> +<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> +<td align="center"><a href="../../../../../../more/index.htm">More</a></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="creation_and_modification.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../spatial_indexes.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="rtree_examples.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="geometry.spatial_indexes.queries"></a><a class="link" href="queries.html" title="Queries">Queries</a> +</h3></div></div></div> +<p> + Queries returns <code class="computeroutput">Value</code>s which meets some predicates. Currently + supported are three types of predicates: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + spatial predicates - spatial conditions that must be met by stored Value + and some Geometry, + </li> +<li class="listitem"> + distance predicates - distance conditions that must be met by stored + Value and some Geometry, + </li> +<li class="listitem"> + user-defined unary predicate - function, function object or lambda expression + checking user-defined condition. + </li> +</ul></div> +<p> + For example queries may be used to retrieve Values: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + intersecting some area but not within other area, + </li> +<li class="listitem"> + are nearest to some point, + </li> +<li class="listitem"> + overlapping a box and has user-defined property. + </li> +</ul></div> +<h5> +<a name="geometry.spatial_indexes.queries.h0"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.performing_a_query"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.performing_a_query">Performing + a query</a> + </h5> +<p> + There are three ways to perform a query presented below. All of them returns + <code class="computeroutput">Value</code>s intersecting some region defined as a <code class="computeroutput">Box</code>. + </p> +<p> + Method call + </p> +<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span>Value<span class="special">></span> <span class="identifier">returned_values</span><span class="special">;</span> +Box <span class="identifier">box_region</span><span class="special">(...);</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box_region</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">returned_values</span><span class="special">));</span> +</pre> +<p> + Function call + </p> +<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span>Value<span class="special">></span> <span class="identifier">returned_values</span><span class="special">;</span> +Box <span class="identifier">box_region</span><span class="special">(...);</span> +<span class="identifier">index</span><span class="special">::</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">rt</span><span class="special">,</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box_region</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">returned_values</span><span class="special">));</span> +</pre> +<p> + Use of pipe operator generating a range + </p> +<pre class="programlisting">Box <span class="identifier">box_region</span><span class="special">(...);</span> +<span class="identifier">BOOST_FOREACH</span><span class="special">(</span>Value <span class="special">&</span> <span class="identifier">v</span><span class="special">,</span> <span class="identifier">rt</span> <span class="special">|</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">queried</span><span class="special">(</span><span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box_region</span><span class="special">)))</span> + <span class="special">;</span> <span class="comment">// do something with v</span> +</pre> +<h5> +<a name="geometry.spatial_indexes.queries.h1"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.spatial_predicates"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.spatial_predicates">Spatial + predicates</a> + </h5> +<p> + Queries using spatial predicates returns <code class="computeroutput">Value</code>s which are related + somehow to some Geometry - box, polygon, etc. Names of spatial predicates + correspond to names of Boost.Geometry algorithms. Examples of some basic + queries may be found in tables below. The query region and result <code class="computeroutput"><span class="identifier">Value</span></code>s are orange. + </p> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +<col> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + intersects(Box) + </p> + </th> +<th> + <p> + covered_by(Box) + </p> + </th> +<th> + <p> + disjoint(Box) + </p> + </th> +<th> + <p> + overlaps(Box) + </p> + </th> +<th> + <p> + within(Box) + </p> + </th> +</tr></thead> +<tbody><tr> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/intersects.png" alt="intersects"></span> + </p> + </td> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/within.png" alt="within"></span> + </p> + </td> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/disjoint.png" alt="disjoint"></span> + </p> + </td> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/overlaps.png" alt="overlaps"></span> + </p> + </td> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/within.png" alt="within"></span> + </p> + </td> +</tr></tbody> +</table></div> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + intersects(Ring) + </p> + </th> +<th> + <p> + intersects(Polygon) + </p> + </th> +<th> + <p> + intersects(MultiPolygon) + </p> + </th> +</tr></thead> +<tbody><tr> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/intersects_ring.png" alt="intersects_ring"></span> + </p> + </td> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/intersects_poly.png" alt="intersects_poly"></span> + </p> + </td> +<td> + <p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/intersects_mpoly.png" alt="intersects_mpoly"></span> + </p> + </td> +</tr></tbody> +</table></div> +<p> + To use a spatial predicate one may use one of the functions defined in <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">index</span></code> namespace. + </p> +<pre class="programlisting"><span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">covered_by</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">disjont</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">overlaps</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">within</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +</pre> +<p> + All spatial predicates may be negated, e.g.: + </p> +<pre class="programlisting"><span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(!</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="comment">// the same as</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">disjoint</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +</pre> +<h5> +<a name="geometry.spatial_indexes.queries.h2"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.distance_predicates"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.distance_predicates">Distance predicates</a> + </h5> +<h6> +<a name="geometry.spatial_indexes.queries.h3"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.nearest_neighbours_queries"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.nearest_neighbours_queries">Nearest + neighbours queries</a> + </h6> +<p> + Nearest neighbours queries returns <code class="computeroutput">Value</code>s which are closest + to some point in space. Additionally it is possible to define how the distance + to the <code class="computeroutput"><span class="identifier">Value</span></code> should be calculated. + The example of knn query is presented below. 5 <code class="computeroutput">Value</code>s nearest + to some point are orange. + </p> +<p> + <span class="inlinemediaobject"><img src="../../img/index/rtree/knn.png" alt="knn"></span> + </p> +<h6> +<a name="geometry.spatial_indexes.queries.h4"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.k_nearest_neighbours"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.k_nearest_neighbours">k nearest + neighbours</a> + </h6> +<p> + There are three ways of performing knn queries. Following queries returns + <code class="computeroutput"><span class="identifier">k</span></code> <code class="computeroutput">Value</code>s closest + to some point in space. For <code class="computeroutput">Box</code>es <code class="computeroutput">Indexable</code>s the + distance to the nearest point is calculated by default. + </p> +<p> + Method call + </p> +<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span>Value<span class="special">></span> <span class="identifier">returned_values</span><span class="special">;</span> +Point <span class="identifier">pt</span><span class="special">(...);</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="identifier">k</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">returned_values</span><span class="special">));</span> +</pre> +<p> + Function call + </p> +<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span>Value<span class="special">></span> <span class="identifier">returned_values</span><span class="special">;</span> +Point <span class="identifier">pt</span><span class="special">(...);</span> +<span class="identifier">index</span><span class="special">::</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">rt</span><span class="special">,</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="identifier">k</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">returned_values</span><span class="special">));</span> +</pre> +<p> + Use of <code class="computeroutput"><span class="keyword">operator</span> <span class="special">|</span></code> + </p> +<pre class="programlisting">Point <span class="identifier">pt</span><span class="special">(...);</span> +<span class="identifier">BOOST_FOREACH</span><span class="special">(</span>Value <span class="special">&</span> <span class="identifier">v</span><span class="special">,</span> <span class="identifier">rt</span> <span class="special">|</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">queried</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="identifier">k</span><span class="special">)))</span> + <span class="special">;</span> <span class="comment">// do something with v</span> +</pre> +<h5> +<a name="geometry.spatial_indexes.queries.h5"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.user_defined_unary_predicate"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.user_defined_unary_predicate">User-defined + unary predicate</a> + </h5> +<p> + The user may pass a <code class="computeroutput"><span class="identifier">UnaryPredicate</span></code> + - function, function object or lambda expression taking const reference to + Value and returning bool. This object may be passed to the query in order + to check if <code class="computeroutput">Value</code> should be returned by the query. To do it + one may use <code class="computeroutput"><span class="identifier">index</span><span class="special">::</span><span class="identifier">satisfies</span><span class="special">()</span></code> + function like on the example below: + </p> +<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">is_red</span><span class="special">(</span>Value <span class="keyword">const</span><span class="special">&</span> <span class="identifier">v</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">return</span> <span class="identifier">v</span><span class="special">.</span><span class="identifier">is_red</span><span class="special">();</span> +<span class="special">}</span> + +<span class="keyword">struct</span> <span class="identifier">is_red_o</span> +<span class="special">{</span> + <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Value</span><span class="special">></span> + <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">()(</span>Value <span class="keyword">const</span><span class="special">&</span> <span class="identifier">v</span><span class="special">)</span> + <span class="special">{</span> + <span class="keyword">return</span> <span class="identifier">v</span><span class="special">.</span><span class="identifier">is_red</span><span class="special">();</span> + <span class="special">}</span> +<span class="special">}</span> + +<span class="comment">// ...</span> + +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">satisfies</span><span class="special">(</span><span class="identifier">is_red</span><span class="special">),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> + +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">satisfies</span><span class="special">(</span><span class="identifier">is_red_o</span><span class="special">()),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> + +<span class="preprocessor">#ifndef</span> <span class="identifier">BOOST_NO_CXX11_LAMBDAS</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">satisfies</span><span class="special">([](</span>Value <span class="keyword">const</span><span class="special">&</span> <span class="identifier">v</span><span class="special">)</span> <span class="special">{</span> <span class="keyword">return</span> <span class="identifier">v</span><span class="special">.</span><span class="identifier">is_red</span><span class="special">();</span> <span class="special">}),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="preprocessor">#endif</span> +</pre> +<p> + <code class="computeroutput"><span class="identifier">satisfies</span><span class="special">()</span></code> + may be negated, e.g.: + </p> +<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">is_red</span><span class="special">(</span>Value <span class="keyword">const</span><span class="special">&</span> <span class="identifier">v</span><span class="special">)</span> <span class="special">{</span> <span class="keyword">return</span> <span class="identifier">v</span><span class="special">.</span><span class="identifier">is_red</span><span class="special">();</span> <span class="special">}</span> +<span class="keyword">bool</span> <span class="identifier">is_not_red</span><span class="special">(</span>Value <span class="keyword">const</span><span class="special">&</span> <span class="identifier">v</span><span class="special">)</span> <span class="special">{</span> <span class="keyword">return</span> <span class="special">!</span><span class="identifier">v</span><span class="special">.</span><span class="identifier">is_red</span><span class="special">();</span> <span class="special">}</span> + +<span class="comment">// ...</span> + +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">satisfies</span><span class="special">(</span><span class="identifier">is_red</span><span class="special">),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="comment">// the same as</span> +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">)</span> <span class="special">&&</span> <span class="special">!</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">satisfies</span><span class="special">(</span><span class="identifier">is_not_red</span><span class="special">),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +</pre> +<h5> +<a name="geometry.spatial_indexes.queries.h6"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.passing_a_set_of_predicates"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.passing_a_set_of_predicates">Passing + a set of predicates</a> + </h5> +<p> + It's possible to use some number of predicates in one query by connecting + them with <code class="computeroutput"><span class="keyword">operator</span><span class="special">&&</span></code> + e.g. <code class="computeroutput"><span class="identifier">Pred1</span> <span class="special">&&</span> + <span class="identifier">Pred2</span> <span class="special">&&</span> + <span class="identifier">Pred3</span> <span class="special">&&</span> + <span class="special">...</span></code>. + </p> +<p> + These predicates are connected by logical AND. Passing all predicates together + not only makes possible to construct advanced queries but is also faster + than separate calls because the tree is traversed only once. Traversing is + continued and <code class="computeroutput"><span class="identifier">Value</span></code>s are + returned only if all predicates are met. Predicates are checked left-to-right + so placing most restrictive predicates first should accelerate the search. + </p> +<pre class="programlisting"><span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box1</span><span class="special">)</span> <span class="special">&&</span> <span class="special">!</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">within</span><span class="special">(</span><span class="identifier">box2</span><span class="special">),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> + +<span class="identifier">rt</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box1</span><span class="special">)</span> <span class="special">&&</span> <span class="special">!</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">within</span><span class="special">(</span><span class="identifier">box2</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">overlaps</span><span class="special">(</span><span class="identifier">box3</span><span class="special">),</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +</pre> +<p> + Of course it's possible to connect different types of predicates together. + </p> +<pre class="programlisting"><span class="identifier">index</span><span class="special">::</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">rt</span><span class="special">,</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="identifier">k</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">within</span><span class="special">(</span><span class="identifier">b</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">returned_values</span><span class="special">));</span> + +<span class="identifier">BOOST_FOREACH</span><span class="special">(</span><span class="identifier">Value</span> <span class="special">&</span> <span class="identifier">v</span><span class="special">,</span> <span class="identifier">rt</span> <span class="special">|</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">queried</span><span class="special">(</span><span class="identifier">index</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="identifier">k</span><span class="special">)</span> <span class="special">&&</span> <span class="identifier">index</span><span class="special">::</span><span class="identifier">covered_by</span><span class="special">(</span><span class="identifier">b</span><span class="special">)))</span> + <span class="special">;</span> <span class="comment">// do something with v</span> +</pre> +<h5> +<a name="geometry.spatial_indexes.queries.h7"></a> + <span class="phrase"><a name="geometry.spatial_indexes.queries.inserting_query_results_into_the_other_r_tree"></a></span><a class="link" href="queries.html#geometry.spatial_indexes.queries.inserting_query_results_into_the_other_r_tree">Inserting + query results into the other R-tree</a> + </h5> +<p> + There are several ways of inserting Values returned by a query to the other + R-tree container. The most basic way is creating a temporary container for + Values and insert them later. + </p> +<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">bgi</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">geometry</span><span class="special">::</span><span class="identifier">index</span><span class="special">;</span> +<span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">Box</span><span class="special">,</span> <span class="keyword">int</span><span class="special">></span> Value<span class="special">;</span> +<span class="keyword">typedef</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">rtree</span><span class="special"><</span> Value<span class="special">,</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">linear</span><span class="special"><</span><span class="number">32</span><span class="special">,</span> <span class="number">8</span><span class="special">></span> <span class="special">></span> <span class="identifier">RTree</span><span class="special">;</span> + +<span class="identifier">RTree</span> <span class="identifier">rt1</span><span class="special">;</span> +<span class="comment">/* some inserting into the tree */</span> + +<span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="identifier">Value</span><span class="special">></span> <span class="identifier">result</span><span class="special">;</span> +<span class="identifier">rt1</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">Box</span><span class="special">(/*...*/)),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span> +<span class="identifier">RTree</span> <span class="identifier">rt2</span><span class="special">(</span><span class="identifier">result</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">result</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span> +</pre> +<p> + However there are better ways. One of these methods is mentioned in the "Creation + and modification" section. The insert iterator may be passed directly + into the query. + </p> +<pre class="programlisting"><span class="identifier">RTree</span> <span class="identifier">rt3</span><span class="special">;</span> +<span class="identifier">rt1</span><span class="special">.</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">Box</span><span class="special">(/*...*/))),</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">inserter</span><span class="special">(</span><span class="identifier">rt3</span><span class="special">));</span> +</pre> +<p> + If you like Boost.Range you'll appreciate the third option. You may pass + the result Range directly into the constructor. + </p> +<pre class="programlisting"><span class="identifier">RTree</span> <span class="identifier">rt4</span><span class="special">(</span><span class="identifier">rt1</span> <span class="special">|</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">queried</span><span class="special">(</span><span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">Box</span><span class="special">(/*...*/)))));</span> +</pre> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"></td> +<td align="right"><div class="copyright-footer">Copyright © 2009-2013 Barend Gehrels, Bruno Lalande, Mateusz Loskot, Adam Wulkiewicz<p> + Distributed under the Boost Software License, Version 1.0. (See accompanying + file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="creation_and_modification.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../spatial_indexes.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="rtree_examples.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |