org.jpedal.function.PDFCalculator Maven / Gradle / Ivy
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/*
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.idrsolutions.com
* Help section for developers at http://www.idrsolutions.com/java-pdf-library-support/
*
* (C) Copyright 1997-2013, IDRsolutions and Contributors.
*
* This file is part of JPedal
*
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* ---------------
* PDFCalculator.java
* ---------------
*/
package org.jpedal.function;
import org.jpedal.utils.LogWriter;
/**
* Class to handle Type 4 shading (PostScript Calculator) from a Pdf
*/
public class PDFCalculator extends PDFGenericFunction implements PDFFunction {
private static final long serialVersionUID = -2771458940865489908L;
int returnValues;
byte[] stream;
public PDFCalculator(byte[] stream, float[] domain, float[] range) {
super(domain, range);
this.returnValues = range.length / 2;
/**
* set stream
*/
this.stream = stream; // raw data
}
/**
* Calculate the output values for this point in the shading object. (Only used by Stitching)
*
* @return returns the shading values for this point
*/
@Override
public float[] computeStitch(float[] subinput) {
return compute(subinput);
}
@Override
public float[] compute(float[] values) {
float[] output = new float[this.returnValues];
float[] result = new float[this.returnValues];
try {
PostscriptFactory post = new PostscriptFactory(this.stream);
post.resetStacks(values);
double[] stack = post.executePostscript();
if ((this.domain.length / 2) == 1) {
for (int i = 0, imax = this.range.length / 2; i < imax; i++) {
output[i] = (float) (stack[i]); // take output from stack
result[i] = min(max(output[i], this.range[i * 2]), this.range[i * 2 + 1]);
}
}
else {
for (int i = 0, imax = this.range.length / 2; i < imax; i++) {
output[i] = (float) (stack[i]); // take output from stack
result[i] = min(max(output[i], this.range[i * 2]), this.range[i * 2 + 1]);
}
}
}
catch (Exception e) {
// tell user and log
if (LogWriter.isOutput()) LogWriter.writeLog("Exception: " + e.getMessage());
}
return result;
}
}