PDHighlightAppearanceHandler.java
/*
* Copyright 2018 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.pdfbox.pdmodel.interactive.annotation.handlers;
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.PDFormContentStream;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.graphics.blend.BlendMode;
import org.apache.pdfbox.pdmodel.graphics.color.PDColor;
import org.apache.pdfbox.pdmodel.graphics.form.PDFormXObject;
import org.apache.pdfbox.pdmodel.graphics.state.PDExtendedGraphicsState;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotation;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotationHighlight;
import org.apache.pdfbox.pdmodel.PDAppearanceContentStream;
import org.apache.pdfbox.pdmodel.PDDocument;
/**
*
* @author Tilman Hausherr
*/
public class PDHighlightAppearanceHandler extends PDAbstractAppearanceHandler
{
private static final Log LOG = LogFactory.getLog(PDHighlightAppearanceHandler.class);
public PDHighlightAppearanceHandler(PDAnnotation annotation)
{
super(annotation);
}
public PDHighlightAppearanceHandler(PDAnnotation annotation, PDDocument document)
{
super(annotation, document);
}
@Override
public void generateNormalAppearance()
{
PDAnnotationHighlight annotation = (PDAnnotationHighlight) getAnnotation();
float[] pathsArray = annotation.getQuadPoints();
if (pathsArray == null)
{
return;
}
PDColor color = annotation.getColor();
if (color == null || color.getComponents().length == 0)
{
return;
}
PDRectangle rect = annotation.getRectangle();
if (rect == null)
{
return;
}
AnnotationBorder ab = AnnotationBorder.getAnnotationBorder(annotation, annotation.getBorderStyle());
// Adjust rectangle even if not empty, see PLPDF.com-MarkupAnnotations.pdf
//TODO in a class structure this should be overridable
// this is similar to polyline but different data type
//TODO padding should consider the curves too; needs to know in advance where the curve is
float minX = Float.MAX_VALUE;
float minY = Float.MAX_VALUE;
float maxX = Float.MIN_VALUE;
float maxY = Float.MIN_VALUE;
for (int i = 0; i < pathsArray.length / 2; ++i)
{
float x = pathsArray[i * 2];
float y = pathsArray[i * 2 + 1];
minX = Math.min(minX, x);
minY = Math.min(minY, y);
maxX = Math.max(maxX, x);
maxY = Math.max(maxY, y);
}
// get the delta used for curves and use it for padding
float maxDelta = 0;
for (int i = 0; i < pathsArray.length / 8; ++i)
{
// one of the two is 0, depending whether the rectangle is
// horizontal or vertical
// if it is diagonal then... uh...
float delta = Math.max((pathsArray[i + 0] - pathsArray[i + 4]) / 4,
(pathsArray[i + 1] - pathsArray[i + 5]) / 4);
maxDelta = Math.max(delta, maxDelta);
}
rect.setLowerLeftX(Math.min(minX - ab.width / 2 - maxDelta, rect.getLowerLeftX()));
rect.setLowerLeftY(Math.min(minY - ab.width / 2 - maxDelta, rect.getLowerLeftY()));
rect.setUpperRightX(Math.max(maxX + ab.width + maxDelta, rect.getUpperRightX()));
rect.setUpperRightY(Math.max(maxY + ab.width + maxDelta, rect.getUpperRightY()));
annotation.setRectangle(rect);
try (PDAppearanceContentStream cs = getNormalAppearanceAsContentStream())
{
PDExtendedGraphicsState r0 = new PDExtendedGraphicsState();
PDExtendedGraphicsState r1 = new PDExtendedGraphicsState();
r0.setAlphaSourceFlag(false);
r0.setStrokingAlphaConstant(annotation.getConstantOpacity());
r0.setNonStrokingAlphaConstant(annotation.getConstantOpacity());
r1.setAlphaSourceFlag(false);
r1.setBlendMode(BlendMode.MULTIPLY);
cs.setGraphicsStateParameters(r0);
cs.setGraphicsStateParameters(r1);
PDFormXObject frm1 = new PDFormXObject(createCOSStream());
PDFormXObject frm2 = new PDFormXObject(createCOSStream());
frm1.setResources(new PDResources());
try (PDFormContentStream mwfofrmCS = new PDFormContentStream(frm1))
{
mwfofrmCS.drawForm(frm2);
}
frm1.setBBox(annotation.getRectangle());
COSDictionary groupDict = new COSDictionary();
groupDict.setItem(COSName.S, COSName.TRANSPARENCY);
//TODO PDFormXObject.setGroup() is missing
frm1.getCOSObject().setItem(COSName.GROUP, groupDict);
cs.drawForm(frm1);
frm2.setBBox(annotation.getRectangle());
try (PDFormContentStream frm2CS = new PDFormContentStream(frm2))
{
frm2CS.setNonStrokingColor(color);
int of = 0;
while (of + 7 < pathsArray.length)
{
// quadpoints spec sequence is incorrect, correct one is (4,5 0,1 2,3 6,7)
// https://stackoverflow.com/questions/9855814/pdf-spec-vs-acrobat-creation-quadpoints
// for "curvy" highlighting, two Bézier control points are used that seem to have a
// distance of about 1/4 of the height.
// note that curves won't appear if outside of the rectangle
float delta = 0;
if (Float.compare(pathsArray[of + 0], pathsArray[of + 4]) == 0 &&
Float.compare(pathsArray[of + 1], pathsArray[of + 3]) == 0 &&
Float.compare(pathsArray[of + 2], pathsArray[of + 6]) == 0 &&
Float.compare(pathsArray[of + 5], pathsArray[of + 7]) == 0)
{
// horizontal highlight
delta = (pathsArray[of + 1] - pathsArray[of + 5]) / 4;
}
else if (Float.compare(pathsArray[of + 1], pathsArray[of + 5]) == 0 &&
Float.compare(pathsArray[of + 0], pathsArray[of + 2]) == 0 &&
Float.compare(pathsArray[of + 3], pathsArray[of + 7]) == 0 &&
Float.compare(pathsArray[of + 4], pathsArray[of + 6]) == 0)
{
// vertical highlight
delta = (pathsArray[of + 0] - pathsArray[of + 4]) / 4;
}
frm2CS.moveTo(pathsArray[of + 4], pathsArray[of + 5]);
if (Float.compare(pathsArray[of + 0], pathsArray[of + 4]) == 0)
{
// horizontal highlight
frm2CS.curveTo(pathsArray[of + 4] - delta, pathsArray[of + 5] + delta,
pathsArray[of + 0] - delta, pathsArray[of + 1] - delta,
pathsArray[of + 0], pathsArray[of + 1]);
}
else if (Float.compare(pathsArray[of + 5], pathsArray[of + 1]) == 0)
{
// vertical highlight
frm2CS.curveTo(pathsArray[of + 4] + delta, pathsArray[of + 5] + delta,
pathsArray[of + 0] - delta, pathsArray[of + 1] + delta,
pathsArray[of + 0], pathsArray[of + 1]);
}
else
{
frm2CS.lineTo(pathsArray[of + 0], pathsArray[of + 1]);
}
frm2CS.lineTo(pathsArray[of + 2], pathsArray[of + 3]);
if (Float.compare(pathsArray[of + 2], pathsArray[of + 6]) == 0)
{
// horizontal highlight
frm2CS.curveTo(pathsArray[of + 2] + delta, pathsArray[of + 3] - delta,
pathsArray[of + 6] + delta, pathsArray[of + 7] + delta,
pathsArray[of + 6], pathsArray[of + 7]);
}
else if (Float.compare(pathsArray[of + 3], pathsArray[of + 7]) == 0)
{
// vertical highlight
frm2CS.curveTo(pathsArray[of + 2] - delta, pathsArray[of + 3] - delta,
pathsArray[of + 6] + delta, pathsArray[of + 7] - delta,
pathsArray[of + 6], pathsArray[of + 7]);
}
else
{
frm2CS.lineTo(pathsArray[of + 6], pathsArray[of + 7]);
}
frm2CS.fill();
of += 8;
}
}
}
catch (IOException ex)
{
LOG.error(ex);
}
}
@Override
public void generateRolloverAppearance()
{
// No rollover appearance generated
}
@Override
public void generateDownAppearance()
{
// No down appearance generated
}
}