/*****************************************************************************
* 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.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.batik.ext.awt.image.PadMode;
import org.apache.batik.ext.awt.image.CompositeRule;
import org.apache.batik.ext.awt.image.renderable.CompositeRable8Bit;
import org.apache.batik.ext.awt.image.renderable.CompositeRable;
import org.apache.batik.ext.awt.image.renderable.Filter;
import org.apache.batik.ext.awt.image.renderable.PadRable8Bit;
import org.apache.batik.gvt.GraphicsNode;
import org.w3c.dom.Element;
/**
* Bridge class for the <feBlend> element.
*
* @author <a href="mailto:tkormann@apache.org">Thierry Kormann</a>
* @version $Id: SVGFeBlendElementBridge.java,v 1.8 2001/03/26 21:27:23 deweese Exp $
*/
public class SVGFeBlendElementBridge
extends SVGAbstractFilterPrimitiveElementBridge {
/**
* Constructs a new bridge for the <feBlend> element.
*/
public SVGFeBlendElementBridge() {}
/**
* 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) {
// 'mode' attribute - default is 'normal'
CompositeRule rule = convertMode(filterElement);
// 'in' attribute
Filter in = getIn(filterElement,
filteredElement,
filteredNode,
inputFilter,
filterMap,
ctx);
if (in == null) {
return null; // disable the filter
}
// 'in2' attribute - required
Filter in2 = getIn2(filterElement,
filteredElement,
filteredNode,
inputFilter,
filterMap,
ctx);
if (in2 == null) {
return null; // disable the filter
}
// 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();
defaultRegion.add(in2.getBounds2D());
}
// get filter primitive chain region
Rectangle2D primitiveRegion
= SVGUtilities.convertFilterPrimitiveRegion(filterElement,
filteredElement,
filteredNode,
defaultRegion,
filterRegion,
ctx);
// build the blend filter
List srcs = new ArrayList(2);
srcs.add(in2);
srcs.add(in);
Filter filter = new CompositeRable8Bit(srcs, rule, true);
filter = new PadRable8Bit(filter, primitiveRegion, PadMode.ZERO_PAD);
// update the filter Map
updateFilterMap(filterElement, filter, filterMap);
return filter;
}
/**
* Converts the 'mode' of the specified feBlend filter primitive.
*
* @param filterElement the filter feBlend element
*/
protected static CompositeRule convertMode(Element filterElement) {
String rule = filterElement.getAttributeNS(null, SVG_MODE_ATTRIBUTE);
if (rule.length() == 0) {
return CompositeRule.OVER;
}
if (SVG_NORMAL_VALUE.equals(rule)) {
return CompositeRule.OVER;
}
if (SVG_MULTIPLY_VALUE.equals(rule)) {
return CompositeRule.MULTIPLY;
}
if (SVG_SCREEN_VALUE.equals(rule)) {
return CompositeRule.SCREEN;
}
if (SVG_DARKEN_VALUE.equals(rule)) {
return CompositeRule.DARKEN;
}
if (SVG_LIGHTEN_VALUE.equals(rule)) {
return CompositeRule.LIGHTEN;
}
throw new BridgeException(filterElement, ERR_ATTRIBUTE_VALUE_MALFORMED,
new Object[] {SVG_MODE_ATTRIBUTE, rule});
}
}