/*
Copyright 2001,2003 The Apache Software Foundation
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package org.apache.batik.svggen;
import java.awt.Rectangle;
import java.awt.image.BufferedImageOp;
import java.awt.image.ConvolveOp;
import java.awt.image.Kernel;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
/**
* Utility class that converts a ConvolveOp object into
* an SVG filter descriptor.
*
* @author <a href="mailto:vincent.hardy@eng.sun.com">Vincent Hardy</a>
* @version $Id: SVGConvolveOp.java,v 1.11 2005/03/27 08:58:35 cam Exp $
* @see org.apache.batik.svggen.SVGBufferedImageOp
*/
public class SVGConvolveOp extends AbstractSVGFilterConverter {
/**
* @param generatorContext used to build Elements
*/
public SVGConvolveOp(SVGGeneratorContext generatorContext) {
super(generatorContext);
}
/**
* Converts a Java 2D API BufferedImageOp into
* a set of attribute/value pairs and related definitions
*
* @param filter BufferedImageOp filter to be converted
* @param filterRect Rectangle, in device space, that defines the area
* to which filtering applies. May be null, meaning that the
* area is undefined.
* @return descriptor of the attributes required to represent
* the input filter
* @see org.apache.batik.svggen.SVGFilterDescriptor
*/
public SVGFilterDescriptor toSVG(BufferedImageOp filter,
Rectangle filterRect){
if(filter instanceof ConvolveOp)
return toSVG((ConvolveOp)filter);
else
return null;
}
/**
* @param convolveOp the ConvolveOp to be converted
* @return a description of the SVG filter corresponding to
* convolveOp. The definition of the feConvolveMatrix
* filter in put in feConvolveMatrixDefSet
*/
public SVGFilterDescriptor toSVG(ConvolveOp convolveOp){
// Reuse definition if convolveOp has already been converted
SVGFilterDescriptor filterDesc =
(SVGFilterDescriptor)descMap.get(convolveOp);
Document domFactory = generatorContext.domFactory;
if (filterDesc == null) {
//
// First time filter is converted: create its corresponding
// SVG filter
//
Kernel kernel = convolveOp.getKernel();
Element filterDef =
domFactory.createElementNS(SVG_NAMESPACE_URI, SVG_FILTER_TAG);
Element feConvolveMatrixDef =
domFactory.createElementNS(SVG_NAMESPACE_URI,
SVG_FE_CONVOLVE_MATRIX_TAG);
// Convert the kernel size
feConvolveMatrixDef.setAttributeNS(null, SVG_ORDER_ATTRIBUTE,
kernel.getWidth() + SPACE +
kernel.getHeight());
// Convert the kernel values
StringBuffer kernelMatrixBuf = new StringBuffer();
float data[] = kernel.getKernelData(null);
for(int i=0; i<data.length; i++){
kernelMatrixBuf.append(doubleString(data[i]));
kernelMatrixBuf.append(SPACE);
}
feConvolveMatrixDef.
setAttributeNS(null, SVG_KERNEL_MATRIX_ATTRIBUTE,
kernelMatrixBuf.toString().trim());
filterDef.appendChild(feConvolveMatrixDef);
filterDef.setAttributeNS(null, ATTR_ID,
generatorContext.idGenerator.
generateID(ID_PREFIX_FE_CONVOLVE_MATRIX));
// Convert the edge mode
if(convolveOp.getEdgeCondition() == ConvolveOp.EDGE_NO_OP)
feConvolveMatrixDef.setAttributeNS(null, SVG_EDGE_MODE_ATTRIBUTE,
SVG_DUPLICATE_VALUE);
else
feConvolveMatrixDef.setAttributeNS(null, SVG_EDGE_MODE_ATTRIBUTE,
SVG_NONE_VALUE);
//
// Create a filter descriptor
//
// Process filter attribute
StringBuffer filterAttrBuf = new StringBuffer(URL_PREFIX);
filterAttrBuf.append(SIGN_POUND);
filterAttrBuf.append(filterDef.getAttributeNS(null, ATTR_ID));
filterAttrBuf.append(URL_SUFFIX);
filterDesc = new SVGFilterDescriptor(filterAttrBuf.toString(),
filterDef);
defSet.add(filterDef);
descMap.put(convolveOp, filterDesc);
}
return filterDesc;
}
}