/*
* 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.
*/
package org.apache.pdfbox.pdmodel.graphics.shading;
import java.awt.Paint;
import java.io.IOException;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.common.COSObjectable;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.common.function.PDFunction;
import org.apache.pdfbox.pdmodel.graphics.color.PDColorSpace;
import org.apache.pdfbox.util.Matrix;
/**
* A Shading Resource.
*
*/
public abstract class PDShading implements COSObjectable
{
private final COSDictionary dictionary;
private COSArray background = null;
private PDRectangle bBox = null;
private PDColorSpace colorSpace = null;
private PDFunction function = null;
private PDFunction[] functionArray = null;
/**
* shading type 1 = function based shading.
*/
public static final int SHADING_TYPE1 = 1;
/**
* shading type 2 = axial shading.
*/
public static final int SHADING_TYPE2 = 2;
/**
* shading type 3 = radial shading.
*/
public static final int SHADING_TYPE3 = 3;
/**
* shading type 4 = Free-Form Gouraud-Shaded Triangle Meshes.
*/
public static final int SHADING_TYPE4 = 4;
/**
* shading type 5 = Lattice-Form Gouraud-Shaded Triangle Meshes.
*/
public static final int SHADING_TYPE5 = 5;
/**
* shading type 6 = Coons Patch Meshes.
*/
public static final int SHADING_TYPE6 = 6;
/**
* shading type 7 = Tensor-Product Patch Meshes.
*/
public static final int SHADING_TYPE7 = 7;
/**
* Default constructor.
*/
public PDShading()
{
dictionary = new COSDictionary();
}
/**
* Constructor using the given shading dictionary.
*
* @param shadingDictionary the dictionary for this shading
*/
public PDShading(COSDictionary shadingDictionary)
{
dictionary = shadingDictionary;
}
/**
* This will get the underlying dictionary.
*
* @return the dictionary for this shading.
*/
@Override
public COSDictionary getCOSObject()
{
return dictionary;
}
/**
* This will return the type.
*
* @return the type of object that this is
*/
public String getType()
{
return COSName.SHADING.getName();
}
/**
* This will set the shading type.
*
* @param shadingType the new shading type
*/
public void setShadingType(int shadingType)
{
dictionary.setInt(COSName.SHADING_TYPE, shadingType);
}
/**
* This will return the shading type.
*
* @return the shading typ
*/
public abstract int getShadingType();
/**
* This will set the background.
*
* @param newBackground the new background
*/
public void setBackground(COSArray newBackground)
{
background = newBackground;
dictionary.setItem(COSName.BACKGROUND, newBackground);
}
/**
* This will return the background.
*
* @return the background
*/
public COSArray getBackground()
{
if (background == null)
{
background = (COSArray) dictionary.getDictionaryObject(COSName.BACKGROUND);
}
return background;
}
/**
* An array of four numbers in the form coordinate system (see below),
* giving the coordinates of the left, bottom, right, and top edges,
* respectively, of the shading's bounding box.
*
* @return the BBox of the form
*/
public PDRectangle getBBox()
{
if (bBox == null)
{
COSArray array = (COSArray) dictionary.getDictionaryObject(COSName.BBOX);
if (array != null)
{
bBox = new PDRectangle(array);
}
}
return bBox;
}
/**
* This will set the BBox (bounding box) for this Shading.
*
* @param newBBox the new BBox
*/
public void setBBox(PDRectangle newBBox)
{
bBox = newBBox;
if (bBox == null)
{
dictionary.removeItem(COSName.BBOX);
}
else
{
dictionary.setItem(COSName.BBOX, bBox.getCOSArray());
}
}
/**
* This will set the AntiAlias value.
*
* @param antiAlias the new AntiAlias value
*/
public void setAntiAlias(boolean antiAlias)
{
dictionary.setBoolean(COSName.ANTI_ALIAS, antiAlias);
}
/**
* This will return the AntiAlias value.
*
* @return the AntiAlias value
*/
public boolean getAntiAlias()
{
return dictionary.getBoolean(COSName.ANTI_ALIAS, false);
}
/**
* This will get the color space or null if none exists.
*
* @return the color space for the shading
* @throws IOException if there is an error getting the color space
*/
public PDColorSpace getColorSpace() throws IOException
{
if (colorSpace == null)
{
COSBase colorSpaceDictionary = dictionary.getDictionaryObject(COSName.CS, COSName.COLORSPACE);
colorSpace = PDColorSpace.create(colorSpaceDictionary);
}
return colorSpace;
}
/**
* This will set the color space for the shading.
*
* @param colorSpace the color space
*/
public void setColorSpace(PDColorSpace colorSpace)
{
this.colorSpace = colorSpace;
if (colorSpace != null)
{
dictionary.setItem(COSName.COLORSPACE, colorSpace.getCOSObject());
}
else
{
dictionary.removeItem(COSName.COLORSPACE);
}
}
/**
* Create the correct PD Model shading based on the COS base shading.
*
* @param resourceDictionary the COS shading dictionary
* @return the newly created shading resources object
* @throws IOException if we are unable to create the PDShading object
*/
public static PDShading create(COSDictionary resourceDictionary) throws IOException
{
PDShading shading = null;
int shadingType = resourceDictionary.getInt(COSName.SHADING_TYPE, 0);
switch (shadingType)
{
case SHADING_TYPE1:
shading = new PDShadingType1(resourceDictionary);
break;
case SHADING_TYPE2:
shading = new PDShadingType2(resourceDictionary);
break;
case SHADING_TYPE3:
shading = new PDShadingType3(resourceDictionary);
break;
case SHADING_TYPE4:
shading = new PDShadingType4(resourceDictionary);
break;
case SHADING_TYPE5:
shading = new PDShadingType5(resourceDictionary);
break;
case SHADING_TYPE6:
shading = new PDShadingType6(resourceDictionary);
break;
case SHADING_TYPE7:
shading = new PDShadingType7(resourceDictionary);
break;
default:
throw new IOException("Error: Unknown shading type " + shadingType);
}
return shading;
}
/**
* This will set the function for the color conversion.
*
* @param newFunction the new function
*/
public void setFunction(PDFunction newFunction)
{
functionArray = null;
function = newFunction;
getCOSObject().setItem(COSName.FUNCTION, newFunction);
}
/**
* This will set the functions COSArray for the color conversion.
*
* @param newFunctions the new COSArray containing all functions
*/
public void setFunction(COSArray newFunctions)
{
functionArray = null;
function = null;
getCOSObject().setItem(COSName.FUNCTION, newFunctions);
}
/**
* This will return the function used to convert the color values.
*
* @return the function
* @throws java.io.IOException if we were not able to create the function.
*/
public PDFunction getFunction() throws IOException
{
if (function == null)
{
COSBase dictionaryFunctionObject = getCOSObject().getDictionaryObject(COSName.FUNCTION);
if (dictionaryFunctionObject != null)
{
function = PDFunction.create(dictionaryFunctionObject);
}
}
return function;
}
/**
* Provide the function(s) of the shading dictionary as array.
*
* @return an array containing the function(s).
* @throws IOException if we were unable to create a function.
*/
private PDFunction[] getFunctionsArray() throws IOException
{
if (functionArray == null)
{
COSBase functionObject = getCOSObject().getDictionaryObject(COSName.FUNCTION);
if (functionObject instanceof COSDictionary)
{
functionArray = new PDFunction[1];
functionArray[0] = PDFunction.create(functionObject);
}
else if (functionObject instanceof COSArray)
{
COSArray functionCOSArray = (COSArray) functionObject;
int numberOfFunctions = functionCOSArray.size();
functionArray = new PDFunction[numberOfFunctions];
for (int i = 0; i < numberOfFunctions; i++)
{
functionArray[i] = PDFunction.create(functionCOSArray.get(i));
}
}
else
{
throw new IOException("mandatory /Function element must be a dictionary or an array");
}
}
return functionArray;
}
/**
* Convert the input value using the functions of the shading dictionary.
*
* @param inputValue the input value
* @return the output values
* @throws IOException thrown if something went wrong
*/
public float[] evalFunction(float inputValue) throws IOException
{
return evalFunction(new float[] { inputValue });
}
/**
* Convert the input values using the functions of the shading dictionary.
*
* @param input the input values
* @return the output values
* @throws IOException thrown if something went wrong
*/
public float[] evalFunction(float[] input) throws IOException
{
PDFunction[] functions = getFunctionsArray();
int numberOfFunctions = functions.length;
float[] returnValues;
if (numberOfFunctions == 1)
{
returnValues = functions[0].eval(input);
}
else
{
returnValues = new float[numberOfFunctions];
for (int i = 0; i < numberOfFunctions; i++)
{
float[] newValue = functions[i].eval(input);
returnValues[i] = newValue[0];
}
}
// From the PDF spec:
// "If the value returned by the function for a given colour component
// is out of range, it shall be adjusted to the nearest valid value."
for (int i = 0; i < returnValues.length; ++i)
{
if (returnValues[i] < 0)
{
returnValues[i] = 0;
}
else if (returnValues[i] > 1)
{
returnValues[i] = 1;
}
}
return returnValues;
}
/**
* Returns an AWT paint which corresponds to this shading
*
* @param matrix the pattern matrix concatenated with that of the parent content stream,
* this matrix which maps the pattern's internal coordinate system to user space
* @return an AWT Paint instance
*/
public abstract Paint toPaint(Matrix matrix);
}