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this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
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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.Shape;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
import org.apache.batik.ext.awt.g2d.GraphicContext;
import org.w3c.dom.Element;
Utility class that converts a Path object into an SVG clip
Author: Vincent Hardy Version: $Id: SVGClip.java 1733416 2016-03-03 07:07:13Z gadams $
/**
* Utility class that converts a Path object into an SVG clip
*
* @author <a href="mailto:vincent.hardy@eng.sun.com">Vincent Hardy</a>
* @version $Id: SVGClip.java 1733416 2016-03-03 07:07:13Z gadams $
*/
public class SVGClip extends AbstractSVGConverter {
Constant used for some degenerate cases
/**
* Constant used for some degenerate cases
*/
public static final Shape ORIGIN = new Line2D.Float(0,0,0,0);
Descriptor to use where there is no clip on an element
/**
* Descriptor to use where there is no clip on an element
*/
public static final SVGClipDescriptor NO_CLIP =
new SVGClipDescriptor(SVG_NONE_VALUE, null);
Used to convert clip object to SVG elements
/**
* Used to convert clip object to SVG elements
*/
private SVGShape shapeConverter;
Params: - generatorContext – used to build Elements
/**
* @param generatorContext used to build Elements
*/
public SVGClip(SVGGeneratorContext generatorContext) {
super(generatorContext);
this.shapeConverter = new SVGShape(generatorContext);
}
Converts part or all of the input GraphicContext into
a set of attribute/value pairs and related definitions.
Params: - gc – GraphicContext to be converted
See Also: Returns: descriptor of the attributes required to represent
some or all of the GraphicContext state, along
with the related definitions
/**
* Converts part or all of the input GraphicContext into
* a set of attribute/value pairs and related definitions.
* @param gc GraphicContext to be converted
* @return descriptor of the attributes required to represent
* some or all of the GraphicContext state, along
* with the related definitions
* @see org.apache.batik.svggen.SVGDescriptor
*/
public SVGDescriptor toSVG(GraphicContext gc) {
Shape clip = gc.getClip();
SVGClipDescriptor clipDesc = null;
if (clip != null) {
StringBuffer clipPathAttrBuf = new StringBuffer(URL_PREFIX);
// First, convert to a GeneralPath so that the
GeneralPath clipPath = new GeneralPath(clip);
// Check if this object is already in the Map
ClipKey clipKey = new ClipKey(clipPath, generatorContext);
clipDesc = (SVGClipDescriptor)descMap.get(clipKey);
if (clipDesc == null) {
Element clipDef = clipToSVG(clip);
if (clipDef == null)
clipDesc = NO_CLIP;
else {
clipPathAttrBuf.append(SIGN_POUND);
clipPathAttrBuf.append(clipDef.getAttributeNS(null, SVG_ID_ATTRIBUTE));
clipPathAttrBuf.append(URL_SUFFIX);
clipDesc = new SVGClipDescriptor(clipPathAttrBuf.toString(),
clipDef);
descMap.put(clipKey, clipDesc);
defSet.add(clipDef);
}
}
} else
clipDesc = NO_CLIP;
return clipDesc;
}
In the following method, an clipping Shape is converted to
an SVG clipPath.
Params: - clip – path to convert to an SVG clipPath
element
/**
* In the following method, an clipping Shape is converted to
* an SVG clipPath.
*
* @param clip path to convert to an SVG clipPath
* element
*/
private Element clipToSVG(Shape clip) {
Element clipDef =
generatorContext.domFactory.createElementNS(SVG_NAMESPACE_URI,
SVG_CLIP_PATH_TAG);
clipDef.setAttributeNS(null, SVG_CLIP_PATH_UNITS_ATTRIBUTE,
SVG_USER_SPACE_ON_USE_VALUE);
clipDef.setAttributeNS(null, SVG_ID_ATTRIBUTE,
generatorContext.
idGenerator.generateID(ID_PREFIX_CLIP_PATH));
Element clipPath = shapeConverter.toSVG(clip);
// unfortunately it may be null because of SVGPath that may produce null
// SVG elements.
if (clipPath != null) {
clipDef.appendChild(clipPath);
return clipDef;
} else {
// Here, we know clip is not null but we got a
// null clipDef. This means we ran into a degenerate
// case which in Java 2D means everything is clippped.
// To provide an equivalent behavior, we clip to a point
clipDef.appendChild(shapeConverter.toSVG(ORIGIN));
return clipDef;
}
}
}
Inner class used to key clip definitions in a Map.
This is needed because we need to test equality
on the value of GeneralPath and GeneralPath's equal
method does not implement that behavior.
/**
* Inner class used to key clip definitions in a Map.
* This is needed because we need to test equality
* on the value of GeneralPath and GeneralPath's equal
* method does not implement that behavior.
*/
class ClipKey {
This clip hash code. Based on the serialized path
data
/**
* This clip hash code. Based on the serialized path
* data
*/
int hashCodeValue = 0;
Params: - proxiedPath – path used as an index in the Map
/**
* @param proxiedPath path used as an index in the Map
*/
public ClipKey(GeneralPath proxiedPath, SVGGeneratorContext gc){
String pathData = SVGPath.toSVGPathData(proxiedPath, gc);
hashCodeValue = pathData.hashCode();
}
Returns: this object's hashcode
/**
* @return this object's hashcode
*/
public int hashCode() {
return hashCodeValue;
}
Params: - clipKey – object to compare
Returns: true if equal, false otherwise
/**
* @param clipKey object to compare
* @return true if equal, false otherwise
*/
public boolean equals(Object clipKey) {
return clipKey instanceof ClipKey
&& hashCodeValue == ((ClipKey) clipKey).hashCodeValue;
}
}