/* An attribute shown as an arrow.
Copyright (c) 2008 The Regents of the University of California.
All rights reserved.
Permission is hereby granted, without written agreement and without
license or royalty fees, to use, copy, modify, and distribute this
software and its documentation for any purpose, provided that the above
copyright notice and the following two paragraphs appear in all copies
of this software.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
ENHANCEMENTS, OR MODIFICATIONS.
PT_COPYRIGHT_VERSION_2
COPYRIGHTENDKEY
*/
package ptolemy.vergil.kernel.attributes;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import ptolemy.data.DoubleToken;
import ptolemy.data.expr.Parameter;
import ptolemy.data.type.BaseType;
import ptolemy.kernel.util.Attribute;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
import ptolemy.kernel.util.NamedObj;
import diva.util.java2d.Polygon2D;
//////////////////////////////////////////////////////////////////////////
//// ArrowAttribute
/**
An attribute shown as an arrow. The length and width of the arrow head can be
set with the <i>arrowLength</i> and <i>arrowWidth</i> parameters.
@author Thomas Huining Feng
@version $Id$
@since Ptolemy II 7.1
@Pt.ProposedRating Red (tfeng)
@Pt.AcceptedRating Red (tfeng)
*/
public class ArrowAttribute extends LineAttribute {
/** Construct an attribute with the given name contained by the
* specified container. The container argument must not be null, or a
* NullPointerException will be thrown. This attribute will use the
* workspace of the container for synchronization and version counts.
* If the name argument is null, then the name is set to the empty
* string. Increment the version of the workspace.
* @param container The container.
* @param name The name of this attribute.
* @exception IllegalActionException If the attribute is not of an
* acceptable class for the container, or if the name contains a period.
* @exception NameDuplicationException If the name coincides with
* an attribute already in the container.
*/
public ArrowAttribute(NamedObj container, String name)
throws IllegalActionException, NameDuplicationException {
super(container, name);
arrowLength = new Parameter(this, "arrowLength");
arrowLength.setTypeEquals(BaseType.DOUBLE);
arrowLength.setExpression("16.0");
arrowWidth = new Parameter(this, "arrowWidth");
arrowWidth.setTypeEquals(BaseType.DOUBLE);
arrowWidth.setExpression("10.0");
_icon.setFillColor(lineColor.asColor());
}
/** Return a default arrow.
* @return An arrow.
*/
public Shape _getDefaultShape() {
return _createArrow(40.0, 40.0, 16.0, 10.0);
}
/** React to a changes in the attributes by changing the icon.
* @param attribute The attribute that changed.
* @exception IllegalActionException If the change is not acceptable
* to this container (should not be thrown).
*/
public void attributeChanged(Attribute attribute)
throws IllegalActionException {
if (attribute == x || attribute == y || attribute == arrowLength
|| attribute == arrowWidth || attribute == lineColor) {
double xValue = ((DoubleToken) x.getToken()).doubleValue();
double yValue = ((DoubleToken) y.getToken()).doubleValue();
double arrowLengthValue = ((DoubleToken) arrowLength.getToken())
.doubleValue();
double arrowWidthValue = ((DoubleToken) arrowWidth.getToken())
.doubleValue();
_icon.setShape(_createArrow(xValue, yValue, arrowLengthValue,
arrowWidthValue));
_icon.setLineColor(lineColor.asColor());
_icon.setFillColor(lineColor.asColor());
} else {
super.attributeChanged(attribute);
}
}
/** Length of the arrow head. Default to 16.0 */
public Parameter arrowLength;
/** Width of the arrow head. Default to 10.0. */
public Parameter arrowWidth;
/** Create an arrow with the given x, y, arrow length and arrow width
* values.
* @param x The x extent.
* @param y The y extent.
* @param arrowLength Length of the arrow head.
* @param arrowWidth Width of the arrow head.
* @return An arrow with the given x, y, arrow length and arrow width
* values.
*/
private static Shape _createArrow(double x, double y, double arrowLength,
double arrowWidth) {
double halfWidth = arrowWidth / 2.0;
Polygon2D polygon = new Polygon2D.Double();
polygon.moveTo(0.0, halfWidth);
polygon.lineTo(arrowLength + 3.0, 0.0);
polygon.lineTo(arrowLength, halfWidth);
polygon.lineTo(Math.sqrt(x * x + y * y), halfWidth);
polygon.lineTo(arrowLength, halfWidth);
polygon.lineTo(arrowLength + 3.0, arrowWidth);
polygon.closePath();
AffineTransform transform = AffineTransform.getRotateInstance(Math
.atan2(y, x));
polygon.transform(transform);
return polygon;
}
}