source: josm/trunk/src/com/kitfox/svg/ClipPath.java@ 6535

/*
 * SVG Salamander
 * Copyright (c) 2004, Mark McKay
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or 
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 *   - Redistributions of source code must retain the above 
 *     copyright notice, this list of conditions and the following
 *     disclaimer.
 *   - Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials 
 *     provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE. 
 * 
 * Mark McKay can be contacted at mark@kitfox.com.  Salamander and other
 * projects can be found at http://www.kitfox.com
 *
 * Created on January 26, 2004, 1:56 AM
 */
package com.kitfox.svg;

import com.kitfox.svg.xml.StyleAttribute;
import java.awt.Shape;
import java.awt.geom.Area;
import java.util.Iterator;

/**
 * @author Mark McKay
 * @author <a href="mailto:mark@kitfox.com">Mark McKay</a>
 */
public class ClipPath extends SVGElement
{

    public static final String TAG_NAME = "clippath";
    public static final int CP_USER_SPACE_ON_USE = 0;
    public static final int CP_OBJECT_BOUNDING_BOX = 1;
    int clipPathUnits = CP_USER_SPACE_ON_USE;

    /**
     * Creates a new instance of Stop
     */
    public ClipPath()
    {
    }

    public String getTagName()
    {
        return TAG_NAME;
    }

    /**
     * Called after the start element but before the end element to indicate
     * each child tag that has been processed
     */
    public void loaderAddChild(SVGLoaderHelper helper, SVGElement child) throws SVGElementException
    {
        super.loaderAddChild(helper, child);
    }

    protected void build() throws SVGException
    {
        super.build();

        StyleAttribute sty = new StyleAttribute();

        clipPathUnits = (getPres(sty.setName("clipPathUnits"))
            && sty.getStringValue().equals("objectBoundingBox"))
            ? CP_OBJECT_BOUNDING_BOX
            : CP_USER_SPACE_ON_USE;
    }

    public int getClipPathUnits()
    {
        return clipPathUnits;
    }

    public Shape getClipPathShape()
    {
        if (children.isEmpty())
        {
            return null;
        }
        if (children.size() == 1)
        {
            return ((ShapeElement) children.get(0)).getShape();
        }

        Area clipArea = null;
        for (Iterator it = children.iterator(); it.hasNext();)
        {
            ShapeElement se = (ShapeElement) it.next();

            if (clipArea == null)
            {
                Shape shape = se.getShape();
                if (shape != null)
                {
                    clipArea = new Area(se.getShape());
                }
                continue;
            }

            Shape shape = se.getShape();
            if (shape != null)
            {
                clipArea.intersect(new Area(shape));
            }
        }

        return clipArea;
    }

    /**
     * Updates all attributes in this diagram associated with a time event. Ie,
     * all attributes with track information.
     *
     * @return - true if this node has changed state as a result of the time
     * update
     */
    public boolean updateTime(double curTime) throws SVGException
    {
        //Get current values for parameters
        StyleAttribute sty = new StyleAttribute();
        boolean shapeChange = false;


        if (getPres(sty.setName("clipPathUnits")))
        {
            String newUnitsStrn = sty.getStringValue();
            int newUnits = newUnitsStrn.equals("objectBoundingBox")
                ? CP_OBJECT_BOUNDING_BOX
                : CP_USER_SPACE_ON_USE;

            if (newUnits != clipPathUnits)
            {
                clipPathUnits = newUnits;
                shapeChange = true;
            }
        }

        if (shapeChange)
        {
            build();
        }

        return shapeChange;
    }
}