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<sect1 id="release-9-0">

<title>Release 9.0</title>

<listitem>

<para>

Correct calculations of <link

linkend="functions-geometry-op-table"><quote>overlap</quote></link>

and <quote>contains</quote> operations over polygons (Teodor Sigaev)

linkend="functions-geometry-op-table"><quote>overlaps</quote></link>

and <quote>contains</quote> operations for polygons (Teodor Sigaev)

</para>

<para>

The polygon <literal>&amp;&amp;</> (overlaps) operator formerly just

checked to see if the two polygons' bounding boxes overlapped. It now

does a more correct check. The polygon <literal>@&gt;</> and

<literal>&lt;@</> (contains/contained by) operators formerly checked

to see if one polygon's vertexes were all contained in the other;

this can wrongly report <quote>true</> for some non-convex polygons.

Now they check that all line segments of one polygon are contained in

the other.

</para>

</listitem>