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<title>Orientation</title>
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<h1>Orientation</h1>
<p class="Decl"><span class="Comment">Del.»</span> <b>function</b> Orientation(<b>const</b> poly: <a href="../Types/Path.htm">TPath</a>): boolean;</p>
<p class="Decl2"><span class="Comment">C++ »</span> <b>bool</b> Orientation(<b>const</b> <a href="../Types/Path.htm">Path</a> &poly); <span class="Comment">// Function in the ClipperLib namespace.</span></p>
<p class="Decl3"><span class="Comment">C# »</span> <b>public static bool</b> Orientation(<a href="../Types/Path.htm">Path</a> poly); <span class="Comment">// Static method of the Clipper class in the ClipperLib namespace.</span></p>
<p class="Body">Orientation is only important to <em>closed</em> paths. Given that vertices are declared in a specific order, orientation refers to the direction (clockwise or counter-clockwise) that these vertices progress around a closed path.<br><br> Orientation is also dependent on axis direction:<br>
<ul>
<li>On <b>Y-axis positive <em>upward</em> displays</b>, Orientation will return true if the polygon's orientation is counter-clockwise.</li>
<li>On <b>Y-axis positive <em>downward</em> displays</b>, Orientation will return true if the polygon's orientation is clockwise.</li>
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<p class="Body"> <img src="../../../../Images/orientation.png" alt="" border="0" align="left"><br style="clear:both"><br> <b>Notes:</b><br>
<ul>
<li>Self-intersecting polygons have indeterminate orientations in which case this function won't return a meaningful value.</li>
<li>The majority of 2D graphic display libraries (eg GDI, GDI+, XLib, Cairo, AGG, Graphics32) and even the SVG file format have their coordinate origins at the top-left corner of their respective viewports <em>with their Y axes increasing downward</em>. However, some display libraries (eg Quartz, OpenGL) have their coordinate origins undefined or in the classic bottom-left position with their Y axes increasing upward.</li>
<li>For Non-Zero filled polygons, the orientation of <a href="../../../Overview/_Body.htm#terminology">holes</a> <em>must be opposite</em> that of <a href="../../../Overview/_Body.htm#terminology">outer</a> polygons.</li>
<li>For closed paths (polygons) in the <em>solution</em> returned by Clipper's Execute method, their orientations will always be <em>true</em> for outer polygons and <em>false</em> for hole polygons (unless the <a href="../Classes/Clipper/Properties/ReverseSolution.htm"><b>ReverseSolution</b></a> property has been enabled).</li>
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<h2 id="Auto-SeeAlso">See Also</h2>
<p class="Body"><a href="../../../Overview/_Body.htm">Overview</a>, <a href="../Classes/Clipper/Properties/ReverseSolution.htm">Clipper.ReverseSolution</a>, <a href="../Types/Path.htm">Path</a></p>
<p class="Copyright" id="auto"> <br><br> Copyright ©2010-2014 Angus Johnson - Clipper 6.2.1 - Help file built on 1-November-2014 <br><br> </p>
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