/*
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.bridge;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.GeneralPath;
import org.apache.batik.dom.util.XLinkSupport;
import org.apache.batik.gvt.text.TextPath;
import org.apache.batik.parser.AWTPathProducer;
import org.apache.batik.parser.ParseException;
import org.apache.batik.parser.PathParser;
import org.w3c.dom.Element;
/**
* Bridge class for the <textPath> element.
*
* @author <a href="mailto:bella.robinson@cmis.csiro.au">Bella Robinson</a>
* @version $Id: SVGTextPathElementBridge.java,v 1.8 2005/03/03 01:19:53 deweese Exp $
*/
public class SVGTextPathElementBridge extends AbstractSVGBridge
implements ErrorConstants {
/**
* Constructs a new bridge for the <textPath> element.
*/
public SVGTextPathElementBridge() {}
/**
* Returns 'textPath'.
*/
public String getLocalName() {
return SVG_TEXT_PATH_TAG;
}
/**
* Creates a TextPath object that represents the path along which the text
* is to be rendered.
*
* @param ctx The bridge context.
* @param textPathElement The <textPath> element.
*
* @return The new TextPath.
*/
public TextPath createTextPath(BridgeContext ctx, Element textPathElement) {
// get the referenced element
String uri = XLinkSupport.getXLinkHref(textPathElement);
Element pathElement = ctx.getReferencedElement(textPathElement, uri);
if ((pathElement == null) ||
(!SVG_NAMESPACE_URI.equals(pathElement.getNamespaceURI())) ||
(!pathElement.getLocalName().equals(SVG_PATH_TAG))) {
// couldn't find the referenced element
// or the referenced element was not a path
throw new BridgeException(textPathElement, ERR_URI_BAD_TARGET,
new Object[] {uri});
}
// construct a shape for the referenced path element
String s = pathElement.getAttributeNS(null, SVG_D_ATTRIBUTE);
Shape pathShape = null;
if (s.length() != 0) {
AWTPathProducer app = new AWTPathProducer();
app.setWindingRule(CSSUtilities.convertFillRule(pathElement));
try {
PathParser pathParser = new PathParser();
pathParser.setPathHandler(app);
pathParser.parse(s);
} catch (ParseException ex) {
throw new BridgeException(pathElement, ERR_ATTRIBUTE_VALUE_MALFORMED,
new Object[] {SVG_D_ATTRIBUTE});
} finally {
pathShape = app.getShape();
}
} else {
throw new BridgeException(pathElement, ERR_ATTRIBUTE_MISSING,
new Object[] {SVG_D_ATTRIBUTE});
}
// if the reference path element has a transform apply the transform
// to the path shape
s = pathElement.getAttributeNS(null, SVG_TRANSFORM_ATTRIBUTE);
if (s.length() != 0) {
AffineTransform tr = SVGUtilities.convertTransform(pathElement,
SVG_TRANSFORM_ATTRIBUTE, s);
pathShape = tr.createTransformedShape(pathShape);
}
// create the TextPath object that we are going to return
TextPath textPath = new TextPath(new GeneralPath(pathShape));
// set the start offset if specified
s = textPathElement.getAttributeNS(null, SVG_START_OFFSET_ATTRIBUTE);
if (s.length() > 0) {
float startOffset = 0;
int percentIndex = s.indexOf("%");
if (percentIndex != -1) {
// its a percentage of the length of the path
float pathLength = textPath.lengthOfPath();
String percentString = s.substring(0,percentIndex);
float startOffsetPercent = 0;
try {
startOffsetPercent = SVGUtilities.convertSVGNumber(percentString);
} catch (NumberFormatException e) {
startOffsetPercent = -1;
}
if (startOffsetPercent < 0) {
throw new BridgeException(textPathElement, ERR_ATTRIBUTE_VALUE_MALFORMED,
new Object[] {SVG_START_OFFSET_ATTRIBUTE, s});
}
startOffset = (float)(startOffsetPercent * pathLength/100.0);
} else {
// its an absolute length
UnitProcessor.Context uctx = UnitProcessor.createContext(ctx, textPathElement);
startOffset = UnitProcessor.svgOtherLengthToUserSpace(s, SVG_START_OFFSET_ATTRIBUTE, uctx);
}
textPath.setStartOffset(startOffset);
}
return textPath;
}
}