/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* 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
* 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.
*/
/* $Id$ */
package org.apache.fop.pdf;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import org.apache.fop.render.gradient.Function;
import org.apache.fop.render.gradient.Function.SubFunctionRenderer;
import org.apache.fop.render.gradient.GradientMaker;
import org.apache.fop.render.gradient.GradientMaker.DoubleFormatter;
/**
* class representing a PDF Function.
*
* PDF Functions represent parameterized mathematical formulas and
* sampled representations with
* arbitrary resolution. Functions are used in two areas: device-dependent
* rasterization information for halftoning and transfer
* functions, and color specification for smooth shading (a PDF 1.3 feature).
*
* All PDF Functions have a FunctionType (0,2,3, or 4), a Domain, and a Range.
*/
public class PDFFunction extends PDFObject {
private final Function function;
private final List<PDFFunction> pdfFunctions;
/**
* create an complete Function object of Type 2, an Exponential Interpolation function.
*
* Use null for an optional object parameter if you choose not to use it.
* For optional int parameters, pass the default.
*
* @param domain List objects of Double objects.
* This is the domain of the function.
* See page 264 of the PDF 1.3 Spec.
* @param range List of Doubles that is the Range of the function.
* See page 264 of the PDF 1.3 Spec.
* @param cZero This is a vector of Double objects which defines the function result
* when x=0.
*
* This attribute is optional.
* It's described on page 268 of the PDF 1.3 spec.
* @param cOne This is a vector of Double objects which defines the function result
* when x=1.
*
* This attribute is optional.
* It's described on page 268 of the PDF 1.3 spec.
* @param interpolationExponentN This is the inerpolation exponent.
*
* This attribute is required.
* PDF Spec page 268
*/
public PDFFunction(List<Double> domain, List<Double> range, float[] cZero, float[] cOne,
double interpolationExponentN) {
this(new Function(domain, range, cZero, cOne, interpolationExponentN));
}
@SuppressWarnings("unchecked")
public PDFFunction(Function function) {
this(function, Collections.EMPTY_LIST);
}
public PDFFunction(Function function, List<PDFFunction> pdfFunctions) {
this.function = function;
this.pdfFunctions = pdfFunctions;
}
public Function getFunction() {
return function;
}
/**
* represent as PDF. Whatever the FunctionType is, the correct
* representation spits out. The sets of required and optional
* attributes are different for each type, but if a required
* attribute's object was constructed as null, then no error
* is raised. Instead, the malformed PDF that was requested
* by the construction is dutifully output.
* This policy should be reviewed.
*
* @return the PDF string.
*/
public byte[] toPDF() {
return toByteString();
}
public byte[] toByteString() {
SubFunctionRenderer subFunctionRenderer = new SubFunctionRenderer() {
public void outputFunction(StringBuilder out, int functionIndex) {
out.append(pdfFunctions.get(functionIndex).referencePDF());
}
};
StringBuilder out = new StringBuilder();
GradientMaker.DoubleFormatter doubleFormatter = new DoubleFormatter() {
public String formatDouble(double d) {
return PDFNumber.doubleOut(d);
}
};
function.output(out, doubleFormatter, subFunctionRenderer);
return encode(out.toString());
}
/** {@inheritDoc} */
protected boolean contentEquals(PDFObject obj) {
if (obj == null) {
return false;
}
if (obj == this) {
return true;
}
if (!(obj instanceof PDFFunction)) {
return false;
}
Function func = ((PDFFunction) obj).function;
if (function.getFunctionType() != func.getFunctionType()) {
return false;
}
if (function.getBitsPerSample() != func.getBitsPerSample()) {
return false;
}
if (function.getOrder() != func.getOrder()) {
return false;
}
if (function.getInterpolationExponentN() != func.getInterpolationExponentN()) {
return false;
}
if (function.getDomain() != null) {
if (!function.getDomain().equals(func.getDomain())) {
return false;
}
} else if (func.getDomain() != null) {
return false;
}
if (function.getRange() != null) {
if (!function.getRange().equals(func.getRange())) {
return false;
}
} else if (func.getRange() != null) {
return false;
}
if (function.getEncode() != null) {
if (!function.getEncode().equals(func.getEncode())) {
return false;
}
} else if (func.getEncode() != null) {
return false;
}
if (!Arrays.equals(function.getCZero(), func.getCZero())) {
return false;
}
if (!Arrays.equals(function.getCOne(), func.getCOne())) {
return false;
}
if (!pdfFunctions.equals(((PDFFunction) obj).pdfFunctions)) {
return false;
}
if (function.getBounds() != null) {
if (!function.getBounds().equals(func.getBounds())) {
return false;
}
} else if (func.getBounds() != null) {
return false;
}
return true;
}
}