com.lowagie.text.pdf.parser.Matrix Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of itext2 Show documentation
Show all versions of itext2 Show documentation
Itext is a java library to create and manipulate PDFs.
This is a fork of version 2.1.7 the last MPL/LGPL version.
It's focused basically on mantain compatibility with newer bouncycastle releases and small bugfixes.
/*
* Copyright 2008 by Kevin Day.
*
* The contents of this file are subject to the Mozilla Public License Version 1.1
* (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the License.
*
* The Original Code is 'iText, a free JAVA-PDF library'.
*
* The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
* the Initial Developer are Copyright (C) 1999-2008 by Bruno Lowagie.
* All Rights Reserved.
* Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
* are Copyright (C) 2000-2008 by Paulo Soares. All Rights Reserved.
*
* Contributor(s): all the names of the contributors are added in the source code
* where applicable.
*
* Alternatively, the contents of this file may be used under the terms of the
* LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
* provisions of LGPL are applicable instead of those above. If you wish to
* allow use of your version of this file only under the terms of the LGPL
* License and not to allow others to use your version of this file under
* the MPL, indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by the LGPL.
* If you do not delete the provisions above, a recipient may use your version
* of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the MPL as stated above or under the terms of the GNU
* Library General Public License as published by the Free Software Foundation;
* either version 2 of the License, or 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 Library general Public License for more
* details.
*
* If you didn't download this code from the following link, you should check if
* you aren't using an obsolete version:
* http://www.lowagie.com/iText/
*/
package com.lowagie.text.pdf.parser;
import java.util.Arrays;
/**
* Keeps all the values of a 3 by 3 matrix
* and allows you to do some math with matrices.
* @since 2.1.4
*/
public class Matrix {
/** an array position referring to a specific value in the matrix. */
public static final int I11 = 0;
/** an array position referring to a specific value in the matrix. */
public static final int I12 = 1;
/** an array position referring to a specific value in the matrix. */
public static final int I13 = 2;
/** an array position referring to a specific value in the matrix. */
public static final int I21 = 3;
/** an array position referring to a specific value in the matrix. */
public static final int I22 = 4;
/** an array position referring to a specific value in the matrix. */
public static final int I23 = 5;
/** an array position referring to a specific value in the matrix. */
public static final int I31 = 6;
/** an array position referring to a specific value in the matrix. */
public static final int I32 = 7;
/** an array position referring to a specific value in the matrix. */
public static final int I33 = 8;
/** the values inside the matrix (the identity matrix by default). */
private final float[] vals = new float[]{
1,0,0,
0,1,0,
0,0,1
};
/**
* constructs a new Matrix with identity.
*/
public Matrix() {
}
/**
* Constructs a matrix that represents translation
* @param tx
* @param ty
*/
public Matrix(float tx, float ty){
vals[I31] = tx;
vals[I32] = ty;
}
/**
* Creates a Matrix with 6 specified entries
* @param a
* @param b
* @param c
* @param d
* @param e
* @param f
*/
public Matrix(float a, float b, float c, float d, float e, float f){
vals[I11] = a;
vals[I12] = b;
vals[I13] = 0;
vals[I21] = c;
vals[I22] = d;
vals[I23] = 0;
vals[I31] = e;
vals[I32] = f;
vals[I33] = 1;
}
/**
* Gets a specific value inside the matrix.
* @param index an array index corresponding with a value inside the matrix
* @return the value at that specific position.
*/
public float get(int index){
return vals[index];
}
/**
* multiplies this matrix by 'b' and returns the result
* See http://en.wikipedia.org/wiki/Matrix_multiplication
* @param by The matrix to multiply by
* @return the resulting matrix
*/
public Matrix multiply(Matrix by){
Matrix rslt = new Matrix();
float[] a = vals;
float[] b = by.vals;
float[] c = rslt.vals;
c[I11] = a[I11]*b[I11] + a[I12]*b[I21] + a[I13]*b[I31];
c[I12] = a[I11]*b[I12] + a[I12]*b[I22] + a[I13]*b[I32];
c[I13] = a[I11]*b[I13] + a[I12]*b[I23] + a[I13]*b[I33];
c[I21] = a[I21]*b[I11] + a[I22]*b[I21] + a[I23]*b[I31];
c[I22] = a[I21]*b[I12] + a[I22]*b[I22] + a[I23]*b[I32];
c[I23] = a[I21]*b[I13] + a[I22]*b[I23] + a[I23]*b[I33];
c[I31] = a[I31]*b[I11] + a[I32]*b[I21] + a[I33]*b[I31];
c[I32] = a[I31]*b[I12] + a[I32]*b[I22] + a[I33]*b[I32];
c[I33] = a[I31]*b[I13] + a[I32]*b[I23] + a[I33]*b[I33];
return rslt;
}
/**
* Checks equality of matrices.
* @param obj the other Matrix that needs to be compared with this matrix.
* @return true if both matrices are equal
* @see java.lang.Object#equals(java.lang.Object)
*/
public boolean equals(Object obj) {
if (!(obj instanceof Matrix))
return false;
return Arrays.equals(vals, ((Matrix)obj).vals);
}
/**
* Generates a hash code for this object.
* @return the hash code of this object
* @see java.lang.Object#hashCode()
*/
public int hashCode() {
//return Arrays.hashCode(vals); // JDK 5 code, replaced with the following
int result = 1;
for (int i = 0; i < vals.length; i++)
result = 31 * result + Float.floatToIntBits(vals[i]);
return result;
}
/**
* Generates a String representating of the matrix.
* @return the values, delimited with tabs and newlines.
* @see java.lang.Object#toString()
*/
public String toString() {
return vals[I11] + "\t" + vals[I12] + "\t" + vals[I13] + "\n" +
vals[I21] + "\t" + vals[I22] + "\t" + vals[I13] + "\n" +
vals[I31] + "\t" + vals[I32] + "\t" + vals[I33];
}
}