/*****************************************************************************
* Copyright (C) The Apache Software Foundation. All rights reserved. *
* ------------------------------------------------------------------------- *
* This software is published under the terms of the Apache Software License *
* version 1.1, a copy of which has been included with this distribution in *
* the LICENSE file. *
*****************************************************************************/
package org.apache.batik.bridge;
import java.awt.geom.Rectangle2D;
import java.util.Map;
import java.util.StringTokenizer;
import org.apache.batik.ext.awt.image.PadMode;
import org.apache.batik.ext.awt.image.renderable.Filter;
import org.apache.batik.ext.awt.image.renderable.MorphologyRable8Bit;
import org.apache.batik.ext.awt.image.renderable.MorphologyRable;
import org.apache.batik.ext.awt.image.renderable.PadRable8Bit;
import org.apache.batik.ext.awt.image.renderable.PadRable;
import org.apache.batik.gvt.GraphicsNode;
import org.w3c.dom.Element;
/**
* Bridge class for the <feMorphology> element.
*
* @author <a href="mailto:tkormann@apache.org">Thierry Kormann</a>
* @version $Id: SVGFeMorphologyElementBridge.java,v 1.8 2001/03/27 15:57:04 tkormann Exp $
*/
public class SVGFeMorphologyElementBridge
extends SVGAbstractFilterPrimitiveElementBridge {
/**
* Constructs a new bridge for the <feMorphology> element.
*/
public SVGFeMorphologyElementBridge() {}
/**
* Creates a <tt>Filter</tt> primitive according to the specified
* parameters.
*
* @param ctx the bridge context to use
* @param filterElement the element that defines a filter
* @param filteredElement the element that references the filter
* @param filteredNode the graphics node to filter
*
* @param inputFilter the <tt>Filter</tt> that represents the current
* filter input if the filter chain.
* @param filterRegion the filter area defined for the filter chain
* the new node will be part of.
* @param filterMap a map where the mediator can map a name to the
* <tt>Filter</tt> it creates. Other <tt>FilterBridge</tt>s
* can then access a filter node from the filterMap if they
* know its name.
*/
public Filter createFilter(BridgeContext ctx,
Element filterElement,
Element filteredElement,
GraphicsNode filteredNode,
Filter inputFilter,
Rectangle2D filterRegion,
Map filterMap) {
// 'radius' attribute - default is [0, 0]
float [] radii = convertRadius(filterElement);
if (radii[0] == 0 || radii[1] == 0) {
return null; // disable the filter
}
// 'operator' attribute - default is 'erode'
boolean isDilate = convertOperator(filterElement);
// 'in' attribute
Filter in = getIn(filterElement,
filteredElement,
filteredNode,
inputFilter,
filterMap,
ctx);
if (in == null) {
return null; // disable the filter
}
// feMorphology is a point operation. Therefore, to take the
// filter primitive region into account, only a pad operation
// on the input is required.
// The default region is the union of the input sources
// regions unless 'in' is 'SourceGraphic' in which case the
// default region is the filterChain's region
Filter sourceGraphics = (Filter)filterMap.get(SVG_SOURCE_GRAPHIC_VALUE);
Rectangle2D defaultRegion;
if (in == sourceGraphics) {
defaultRegion = filterRegion;
} else {
defaultRegion = in.getBounds2D();
}
Rectangle2D primitiveRegion
= SVGUtilities.convertFilterPrimitiveRegion(filterElement,
filteredElement,
filteredNode,
defaultRegion,
filterRegion,
ctx);
PadRable pad = new PadRable8Bit(in, primitiveRegion, PadMode.ZERO_PAD);
// build tfilter
Filter morphology
= new MorphologyRable8Bit(pad, radii[0], radii[1], isDilate);
PadRable filter = new PadRable8Bit
(morphology, primitiveRegion, PadMode.ZERO_PAD);
// update the filter Map
updateFilterMap(filterElement, filter, filterMap);
return filter;
}
/**
* Returns the radius (or radii) of the specified feMorphology
* filter primitive.
*
* @param filterElement the feMorphology filter primitive
*/
protected static float [] convertRadius(Element filterElement) {
String s = filterElement.getAttributeNS(null, SVG_RADIUS_ATTRIBUTE);
if (s.length() == 0) {
return new float[] {0, 0};
}
float [] radii = new float[2];
StringTokenizer tokens = new StringTokenizer(s, " ,");
try {
radii[0] = SVGUtilities.convertSVGNumber(tokens.nextToken());
if (tokens.hasMoreTokens()) {
radii[1] = SVGUtilities.convertSVGNumber(tokens.nextToken());
} else {
radii[1] = radii[0];
}
} catch (NumberFormatException ex) {
throw new BridgeException
(filterElement, ERR_ATTRIBUTE_VALUE_MALFORMED,
new Object[] {SVG_RADIUS_ATTRIBUTE, s, ex});
}
if (tokens.hasMoreTokens() || radii[0] < 0 || radii[1] < 0) {
throw new BridgeException
(filterElement, ERR_ATTRIBUTE_VALUE_MALFORMED,
new Object[] {SVG_RADIUS_ATTRIBUTE, s});
}
return radii;
}
/**
* Returns the 'operator' of the specified feMorphology filter
* primitive.
*
* @param filterElement the feMorphology filter primitive
*/
protected static boolean convertOperator(Element filterElement) {
String s = filterElement.getAttributeNS(null, SVG_OPERATOR_ATTRIBUTE);
if (s.length() == 0) {
return false;
}
if (SVG_ERODE_VALUE.equals(s)) {
return false;
}
if (SVG_DILATE_VALUE.equals(s)) {
return true;
}
throw new BridgeException(filterElement, ERR_ATTRIBUTE_VALUE_MALFORMED,
new Object[] {SVG_OPERATOR_ATTRIBUTE, s});
}
}