orientableprimitive.java

GEo 地理操作源代码

/*$************************************************************************************************
 **
 ** $Id: OrientablePrimitive.java,v 1.3.2.1 2004/05/18 11:20:29 desruisseaux Exp $
 **
 ** $Source: /cvsroot/geoapi/src/org/opengis/spatialschema/geometry/primitive/OrientablePrimitive.java,v $
 **
 ** Copyright (C) 2003 Open GIS Consortium, Inc. All Rights Reserved. http://www.opengis.org/Legal/
 **
 *************************************************************************************************/
package org.opengis.spatialschema.geometry.primitive;


/**
 * Primitives that can be mirrored into new geometric objects in terms of their internal local
 * coordinate systems (manifold charts). For curves, the orientation reflects the direction in
 * which the curve is traversed, that is, the sense of its parameterization. When used as boundary
 * curves, the surface being bounded is to the "left" of the oriented curve. For surfaces, the
 * orientation reflects from which direction the local coordinate system can be viewed as right
 * handed, the "top" or the surface being the direction of a completing <var>z</var>-axis that
 * would form a right-handed system. When used as a boundary surface, the bounded solid is "below"
 * the surface. The orientation of points and solids has no immediate geometric interpretation in
 * 3-dimensional space.
 * <br><br>
 * <code>OrientablePrimitive</code> objects are essentially references to geometric primitives
 * that carry an "orientation" reversal flag (either "+" or "-") that determines whether this
 * primitive agrees or disagrees with the orientation of the referenced object.
 *
 * <blockquote><font size=2>
 * <strong>NOTE:</strong> There are several reasons for subclassing the 損ositive