1488 lines
42 KiB
Java
1488 lines
42 KiB
Java
/* AffineTransform.java -- transform coordinates between two 2-D spaces
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Copyright (C) 2000, 2001, 2002, 2004 Free Software Foundation
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package java.awt.geom;
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import java.awt.Shape;
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import java.io.IOException;
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import java.io.ObjectInputStream;
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import java.io.Serializable;
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/**
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* This class represents an affine transformation between two coordinate
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* spaces in 2 dimensions. Such a transform preserves the "straightness"
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* and "parallelness" of lines. The transform is built from a sequence of
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* translations, scales, flips, rotations, and shears.
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*
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* <p>The transformation can be represented using matrix math on a 3x3 array.
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* Given (x,y), the transformation (x',y') can be found by:
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* <pre>
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* [ x'] [ m00 m01 m02 ] [ x ] [ m00*x + m01*y + m02 ]
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* [ y'] = [ m10 m11 m12 ] [ y ] = [ m10*x + m11*y + m12 ]
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* [ 1 ] [ 0 0 1 ] [ 1 ] [ 1 ]
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* </pre>
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* The bottom row of the matrix is constant, so a transform can be uniquely
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* represented (as in {@link #toString()}) by
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* "[[m00, m01, m02], [m10, m11, m12]]".
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*
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* @author Tom Tromey (tromey@cygnus.com)
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* @author Eric Blake (ebb9@email.byu.edu)
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* @since 1.2
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* @status partially updated to 1.4, still has some problems
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*/
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public class AffineTransform implements Cloneable, Serializable
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{
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/**
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* Compatible with JDK 1.2+.
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*/
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private static final long serialVersionUID = 1330973210523860834L;
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/**
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* The transformation is the identity (x' = x, y' = y). All other transforms
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* have either a combination of the appropriate transform flag bits for
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* their type, or the type GENERAL_TRANSFORM.
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*
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #getType()
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*/
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public static final int TYPE_IDENTITY = 0;
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/**
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* The transformation includes a translation - shifting in the x or y
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* direction without changing length or angles.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #getType()
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*/
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public static final int TYPE_TRANSLATION = 1;
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/**
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* The transformation includes a uniform scale - length is scaled in both
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* the x and y directions by the same amount, without affecting angles.
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* This is mutually exclusive with TYPE_GENERAL_SCALE.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #TYPE_MASK_SCALE
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* @see #getType()
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*/
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public static final int TYPE_UNIFORM_SCALE = 2;
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/**
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* The transformation includes a general scale - length is scaled in either
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* or both the x and y directions, but by different amounts; without
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* affecting angles. This is mutually exclusive with TYPE_UNIFORM_SCALE.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #TYPE_MASK_SCALE
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* @see #getType()
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*/
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public static final int TYPE_GENERAL_SCALE = 4;
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/**
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* This constant checks if either variety of scale transform is performed.
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*
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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*/
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public static final int TYPE_MASK_SCALE = 6;
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/**
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* The transformation includes a flip about an axis, swapping between
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* right-handed and left-handed coordinate systems. In a right-handed
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* system, the positive x-axis rotates counter-clockwise to the positive
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* y-axis; in a left-handed system it rotates clockwise.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #getType()
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*/
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public static final int TYPE_FLIP = 64;
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/**
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* The transformation includes a rotation of a multiple of 90 degrees (PI/2
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* radians). Angles are rotated, but length is preserved. This is mutually
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* exclusive with TYPE_GENERAL_ROTATION.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #TYPE_MASK_ROTATION
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* @see #getType()
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*/
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public static final int TYPE_QUADRANT_ROTATION = 8;
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/**
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* The transformation includes a rotation by an arbitrary angle. Angles are
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* rotated, but length is preserved. This is mutually exclusive with
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* TYPE_QUADRANT_ROTATION.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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* @see #TYPE_MASK_ROTATION
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* @see #getType()
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*/
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public static final int TYPE_GENERAL_ROTATION = 16;
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/**
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* This constant checks if either variety of rotation is performed.
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*
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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*/
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public static final int TYPE_MASK_ROTATION = 24;
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/**
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* The transformation is an arbitrary conversion of coordinates which
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* could not be decomposed into the other TYPEs.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_FLIP
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #getType()
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*/
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public static final int TYPE_GENERAL_TRANSFORM = 32;
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/**
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* The X coordinate scaling element of the transform matrix.
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*
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* @serial matrix[0,0]
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*/
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private double m00;
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/**
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* The Y coordinate shearing element of the transform matrix.
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*
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* @serial matrix[1,0]
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*/
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private double m10;
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/**
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* The X coordinate shearing element of the transform matrix.
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*
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* @serial matrix[0,1]
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*/
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private double m01;
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/**
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* The Y coordinate scaling element of the transform matrix.
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*
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* @serial matrix[1,1]
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*/
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private double m11;
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/**
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* The X coordinate translation element of the transform matrix.
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*
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* @serial matrix[0,2]
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*/
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private double m02;
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/**
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* The Y coordinate translation element of the transform matrix.
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*
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* @serial matrix[1,2]
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*/
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private double m12;
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/** The type of this transform. */
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private transient int type;
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/**
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* Construct a new identity transform:
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* <pre>
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* [ 1 0 0 ]
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* [ 0 1 0 ]
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* [ 0 0 1 ]
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* </pre>
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*/
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public AffineTransform()
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{
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m00 = m11 = 1;
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}
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/**
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* Create a new transform which copies the given one.
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*
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* @param tx the transform to copy
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* @throws NullPointerException if tx is null
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*/
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public AffineTransform(AffineTransform tx)
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{
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setTransform(tx);
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}
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/**
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* Construct a transform with the given matrix entries:
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* <pre>
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* [ m00 m01 m02 ]
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* [ m10 m11 m12 ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param m00 the x scaling component
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* @param m10 the y shearing component
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* @param m01 the x shearing component
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* @param m11 the y scaling component
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* @param m02 the x translation component
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* @param m12 the y translation component
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*/
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public AffineTransform(float m00, float m10,
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float m01, float m11,
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float m02, float m12)
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{
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this.m00 = m00;
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this.m10 = m10;
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this.m01 = m01;
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this.m11 = m11;
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this.m02 = m02;
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this.m12 = m12;
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updateType();
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}
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/**
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* Construct a transform from a sequence of float entries. The array must
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* have at least 4 entries, which has a translation factor of 0; or 6
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* entries, for specifying all parameters:
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* <pre>
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* [ f[0] f[2] (f[4]) ]
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* [ f[1] f[3] (f[5]) ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param f the matrix to copy from, with at least 4 (6) entries
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* @throws NullPointerException if f is null
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* @throws ArrayIndexOutOfBoundsException if f is too small
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*/
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public AffineTransform(float[] f)
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{
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m00 = f[0];
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m10 = f[1];
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m01 = f[2];
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m11 = f[3];
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if (f.length >= 6)
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{
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m02 = f[4];
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m12 = f[5];
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}
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updateType();
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}
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/**
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* Construct a transform with the given matrix entries:
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* <pre>
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* [ m00 m01 m02 ]
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* [ m10 m11 m12 ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param m00 the x scaling component
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* @param m10 the y shearing component
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* @param m01 the x shearing component
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* @param m11 the y scaling component
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* @param m02 the x translation component
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* @param m12 the y translation component
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*/
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public AffineTransform(double m00, double m10, double m01,
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double m11, double m02, double m12)
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{
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this.m00 = m00;
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this.m10 = m10;
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this.m01 = m01;
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this.m11 = m11;
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this.m02 = m02;
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this.m12 = m12;
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updateType();
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}
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/**
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* Construct a transform from a sequence of double entries. The array must
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* have at least 4 entries, which has a translation factor of 0; or 6
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* entries, for specifying all parameters:
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* <pre>
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* [ d[0] d[2] (d[4]) ]
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* [ d[1] d[3] (d[5]) ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param d the matrix to copy from, with at least 4 (6) entries
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* @throws NullPointerException if d is null
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* @throws ArrayIndexOutOfBoundsException if d is too small
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*/
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public AffineTransform(double[] d)
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{
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m00 = d[0];
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m10 = d[1];
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m01 = d[2];
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m11 = d[3];
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if (d.length >= 6)
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{
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m02 = d[4];
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m12 = d[5];
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}
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updateType();
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}
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/**
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* Returns a translation transform:
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* <pre>
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* [ 1 0 tx ]
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* [ 0 1 ty ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param tx the x translation distance
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* @param ty the y translation distance
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* @return the translating transform
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*/
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public static AffineTransform getTranslateInstance(double tx, double ty)
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{
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AffineTransform t = new AffineTransform();
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t.setToTranslation(tx, ty);
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return t;
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}
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/**
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* Returns a rotation transform. A positive angle (in radians) rotates
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* the positive x-axis to the positive y-axis:
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* <pre>
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* [ cos(theta) -sin(theta) 0 ]
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* [ sin(theta) cos(theta) 0 ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param theta the rotation angle
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* @return the rotating transform
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*/
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public static AffineTransform getRotateInstance(double theta)
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{
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AffineTransform t = new AffineTransform();
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t.setToRotation(theta);
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return t;
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}
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/**
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* Returns a rotation transform about a point. A positive angle (in radians)
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* rotates the positive x-axis to the positive y-axis. This is the same
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* as calling:
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* <pre>
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* AffineTransform tx = new AffineTransform();
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* tx.setToTranslation(x, y);
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* tx.rotate(theta);
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* tx.translate(-x, -y);
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* </pre>
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*
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* <p>The resulting matrix is:
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* <pre>
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* [ cos(theta) -sin(theta) x-x*cos+y*sin ]
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* [ sin(theta) cos(theta) y-x*sin-y*cos ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param theta the rotation angle
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* @param x the x coordinate of the pivot point
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* @param y the y coordinate of the pivot point
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* @return the rotating transform
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*/
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public static AffineTransform getRotateInstance(double theta,
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double x, double y)
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{
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AffineTransform t = new AffineTransform();
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t.setToTranslation(x, y);
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t.rotate(theta);
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t.translate(-x, -y);
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return t;
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}
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/**
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* Returns a scaling transform:
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* <pre>
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* [ sx 0 0 ]
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* [ 0 sy 0 ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param sx the x scaling factor
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* @param sy the y scaling factor
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* @return the scaling transform
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*/
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public static AffineTransform getScaleInstance(double sx, double sy)
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{
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AffineTransform t = new AffineTransform();
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t.setToScale(sx, sy);
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return t;
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}
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/**
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* Returns a shearing transform (points are shifted in the x direction based
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* on a factor of their y coordinate, and in the y direction as a factor of
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* their x coordinate):
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* <pre>
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* [ 1 shx 0 ]
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* [ shy 1 0 ]
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* [ 0 0 1 ]
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* </pre>
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*
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* @param shx the x shearing factor
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* @param shy the y shearing factor
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* @return the shearing transform
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*/
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public static AffineTransform getShearInstance(double shx, double shy)
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{
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AffineTransform t = new AffineTransform();
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t.setToShear(shx, shy);
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return t;
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}
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/**
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* Returns the type of this transform. The result is always valid, although
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* it may not be the simplest interpretation (in other words, there are
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* sequences of transforms which reduce to something simpler, which this
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* does not always detect). The result is either TYPE_GENERAL_TRANSFORM,
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* or a bit-wise combination of TYPE_TRANSLATION, the mutually exclusive
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* TYPE_*_ROTATIONs, and the mutually exclusive TYPE_*_SCALEs.
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*
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* @return The type.
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*
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* @see #TYPE_IDENTITY
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* @see #TYPE_TRANSLATION
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* @see #TYPE_UNIFORM_SCALE
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* @see #TYPE_GENERAL_SCALE
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* @see #TYPE_QUADRANT_ROTATION
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* @see #TYPE_GENERAL_ROTATION
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* @see #TYPE_GENERAL_TRANSFORM
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*/
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public int getType()
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{
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return type;
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}
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/**
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* Return the determinant of this transform matrix. If the determinant is
|
|
* non-zero, the transform is invertible; otherwise operations which require
|
|
* an inverse throw a NoninvertibleTransformException. A result very near
|
|
* zero, due to rounding errors, may indicate that inversion results do not
|
|
* carry enough precision to be meaningful.
|
|
*
|
|
* <p>If this is a uniform scale transformation, the determinant also
|
|
* represents the squared value of the scale. Otherwise, it carries little
|
|
* additional meaning. The determinant is calculated as:
|
|
* <pre>
|
|
* | m00 m01 m02 |
|
|
* | m10 m11 m12 | = m00 * m11 - m01 * m10
|
|
* | 0 0 1 |
|
|
* </pre>
|
|
*
|
|
* @return the determinant
|
|
* @see #createInverse()
|
|
*/
|
|
public double getDeterminant()
|
|
{
|
|
return m00 * m11 - m01 * m10;
|
|
}
|
|
|
|
/**
|
|
* Return the matrix of values used in this transform. If the matrix has
|
|
* fewer than 6 entries, only the scale and shear factors are returned;
|
|
* otherwise the translation factors are copied as well. The resulting
|
|
* values are:
|
|
* <pre>
|
|
* [ d[0] d[2] (d[4]) ]
|
|
* [ d[1] d[3] (d[5]) ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param d the matrix to store the results into; with 4 (6) entries
|
|
* @throws NullPointerException if d is null
|
|
* @throws ArrayIndexOutOfBoundsException if d is too small
|
|
*/
|
|
public void getMatrix(double[] d)
|
|
{
|
|
d[0] = m00;
|
|
d[1] = m10;
|
|
d[2] = m01;
|
|
d[3] = m11;
|
|
if (d.length >= 6)
|
|
{
|
|
d[4] = m02;
|
|
d[5] = m12;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the X coordinate scaling factor of the matrix.
|
|
*
|
|
* @return m00
|
|
* @see #getMatrix(double[])
|
|
*/
|
|
public double getScaleX()
|
|
{
|
|
return m00;
|
|
}
|
|
|
|
/**
|
|
* Returns the Y coordinate scaling factor of the matrix.
|
|
*
|
|
* @return m11
|
|
* @see #getMatrix(double[])
|
|
*/
|
|
public double getScaleY()
|
|
{
|
|
return m11;
|
|
}
|
|
|
|
/**
|
|
* Returns the X coordinate shearing factor of the matrix.
|
|
*
|
|
* @return m01
|
|
* @see #getMatrix(double[])
|
|
*/
|
|
public double getShearX()
|
|
{
|
|
return m01;
|
|
}
|
|
|
|
/**
|
|
* Returns the Y coordinate shearing factor of the matrix.
|
|
*
|
|
* @return m10
|
|
* @see #getMatrix(double[])
|
|
*/
|
|
public double getShearY()
|
|
{
|
|
return m10;
|
|
}
|
|
|
|
/**
|
|
* Returns the X coordinate translation factor of the matrix.
|
|
*
|
|
* @return m02
|
|
* @see #getMatrix(double[])
|
|
*/
|
|
public double getTranslateX()
|
|
{
|
|
return m02;
|
|
}
|
|
|
|
/**
|
|
* Returns the Y coordinate translation factor of the matrix.
|
|
*
|
|
* @return m12
|
|
* @see #getMatrix(double[])
|
|
*/
|
|
public double getTranslateY()
|
|
{
|
|
return m12;
|
|
}
|
|
|
|
/**
|
|
* Concatenate a translation onto this transform. This is equivalent, but
|
|
* more efficient than
|
|
* <code>concatenate(AffineTransform.getTranslateInstance(tx, ty))</code>.
|
|
*
|
|
* @param tx the x translation distance
|
|
* @param ty the y translation distance
|
|
* @see #getTranslateInstance(double, double)
|
|
* @see #concatenate(AffineTransform)
|
|
*/
|
|
public void translate(double tx, double ty)
|
|
{
|
|
m02 += tx * m00 + ty * m01;
|
|
m12 += tx * m10 + ty * m11;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Concatenate a rotation onto this transform. This is equivalent, but
|
|
* more efficient than
|
|
* <code>concatenate(AffineTransform.getRotateInstance(theta))</code>.
|
|
*
|
|
* @param theta the rotation angle
|
|
* @see #getRotateInstance(double)
|
|
* @see #concatenate(AffineTransform)
|
|
*/
|
|
public void rotate(double theta)
|
|
{
|
|
double c = Math.cos(theta);
|
|
double s = Math.sin(theta);
|
|
double n00 = m00 * c + m01 * s;
|
|
double n01 = m00 * -s + m01 * c;
|
|
double n10 = m10 * c + m11 * s;
|
|
double n11 = m10 * -s + m11 * c;
|
|
m00 = n00;
|
|
m01 = n01;
|
|
m10 = n10;
|
|
m11 = n11;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Concatenate a rotation about a point onto this transform. This is
|
|
* equivalent, but more efficient than
|
|
* <code>concatenate(AffineTransform.getRotateInstance(theta, x, y))</code>.
|
|
*
|
|
* @param theta the rotation angle
|
|
* @param x the x coordinate of the pivot point
|
|
* @param y the y coordinate of the pivot point
|
|
* @see #getRotateInstance(double, double, double)
|
|
* @see #concatenate(AffineTransform)
|
|
*/
|
|
public void rotate(double theta, double x, double y)
|
|
{
|
|
translate(x, y);
|
|
rotate(theta);
|
|
translate(-x, -y);
|
|
}
|
|
|
|
/**
|
|
* Concatenate a scale onto this transform. This is equivalent, but more
|
|
* efficient than
|
|
* <code>concatenate(AffineTransform.getScaleInstance(sx, sy))</code>.
|
|
*
|
|
* @param sx the x scaling factor
|
|
* @param sy the y scaling factor
|
|
* @see #getScaleInstance(double, double)
|
|
* @see #concatenate(AffineTransform)
|
|
*/
|
|
public void scale(double sx, double sy)
|
|
{
|
|
m00 *= sx;
|
|
m01 *= sy;
|
|
m10 *= sx;
|
|
m11 *= sy;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Concatenate a shearing onto this transform. This is equivalent, but more
|
|
* efficient than
|
|
* <code>concatenate(AffineTransform.getShearInstance(sx, sy))</code>.
|
|
*
|
|
* @param shx the x shearing factor
|
|
* @param shy the y shearing factor
|
|
* @see #getShearInstance(double, double)
|
|
* @see #concatenate(AffineTransform)
|
|
*/
|
|
public void shear(double shx, double shy)
|
|
{
|
|
double n00 = m00 + (shy * m01);
|
|
double n01 = m01 + (shx * m00);
|
|
double n10 = m10 + (shy * m11);
|
|
double n11 = m11 + (shx * m10);
|
|
m00 = n00;
|
|
m01 = n01;
|
|
m10 = n10;
|
|
m11 = n11;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Reset this transform to the identity (no transformation):
|
|
* <pre>
|
|
* [ 1 0 0 ]
|
|
* [ 0 1 0 ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*/
|
|
public void setToIdentity()
|
|
{
|
|
m00 = m11 = 1;
|
|
m01 = m02 = m10 = m12 = 0;
|
|
type = TYPE_IDENTITY;
|
|
}
|
|
|
|
/**
|
|
* Set this transform to a translation:
|
|
* <pre>
|
|
* [ 1 0 tx ]
|
|
* [ 0 1 ty ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param tx the x translation distance
|
|
* @param ty the y translation distance
|
|
*/
|
|
public void setToTranslation(double tx, double ty)
|
|
{
|
|
m00 = m11 = 1;
|
|
m01 = m10 = 0;
|
|
m02 = tx;
|
|
m12 = ty;
|
|
type = (tx == 0 && ty == 0) ? TYPE_UNIFORM_SCALE : TYPE_TRANSLATION;
|
|
}
|
|
|
|
/**
|
|
* Set this transform to a rotation. A positive angle (in radians) rotates
|
|
* the positive x-axis to the positive y-axis:
|
|
* <pre>
|
|
* [ cos(theta) -sin(theta) 0 ]
|
|
* [ sin(theta) cos(theta) 0 ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param theta the rotation angle
|
|
*/
|
|
public void setToRotation(double theta)
|
|
{
|
|
double c = Math.cos(theta);
|
|
double s = Math.sin(theta);
|
|
m00 = c;
|
|
m01 = -s;
|
|
m02 = 0;
|
|
m10 = s;
|
|
m11 = c;
|
|
m12 = 0;
|
|
type = (c == 1 ? TYPE_IDENTITY
|
|
: c == 0 || c == -1 ? TYPE_QUADRANT_ROTATION
|
|
: TYPE_GENERAL_ROTATION);
|
|
}
|
|
|
|
/**
|
|
* Set this transform to a rotation about a point. A positive angle (in
|
|
* radians) rotates the positive x-axis to the positive y-axis. This is the
|
|
* same as calling:
|
|
* <pre>
|
|
* tx.setToTranslation(x, y);
|
|
* tx.rotate(theta);
|
|
* tx.translate(-x, -y);
|
|
* </pre>
|
|
*
|
|
* <p>The resulting matrix is:
|
|
* <pre>
|
|
* [ cos(theta) -sin(theta) x-x*cos+y*sin ]
|
|
* [ sin(theta) cos(theta) y-x*sin-y*cos ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param theta the rotation angle
|
|
* @param x the x coordinate of the pivot point
|
|
* @param y the y coordinate of the pivot point
|
|
*/
|
|
public void setToRotation(double theta, double x, double y)
|
|
{
|
|
double c = Math.cos(theta);
|
|
double s = Math.sin(theta);
|
|
m00 = c;
|
|
m01 = -s;
|
|
m02 = x - x * c + y * s;
|
|
m10 = s;
|
|
m11 = c;
|
|
m12 = y - x * s - y * c;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Set this transform to a scale:
|
|
* <pre>
|
|
* [ sx 0 0 ]
|
|
* [ 0 sy 0 ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param sx the x scaling factor
|
|
* @param sy the y scaling factor
|
|
*/
|
|
public void setToScale(double sx, double sy)
|
|
{
|
|
m00 = sx;
|
|
m01 = m02 = m10 = m12 = 0;
|
|
m11 = sy;
|
|
type = (sx != sy ? TYPE_GENERAL_SCALE
|
|
: sx == 1 ? TYPE_IDENTITY : TYPE_UNIFORM_SCALE);
|
|
}
|
|
|
|
/**
|
|
* Set this transform to a shear (points are shifted in the x direction based
|
|
* on a factor of their y coordinate, and in the y direction as a factor of
|
|
* their x coordinate):
|
|
* <pre>
|
|
* [ 1 shx 0 ]
|
|
* [ shy 1 0 ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param shx the x shearing factor
|
|
* @param shy the y shearing factor
|
|
*/
|
|
public void setToShear(double shx, double shy)
|
|
{
|
|
m00 = m11 = 1;
|
|
m01 = shx;
|
|
m10 = shy;
|
|
m02 = m12 = 0;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Set this transform to a copy of the given one.
|
|
*
|
|
* @param tx the transform to copy
|
|
* @throws NullPointerException if tx is null
|
|
*/
|
|
public void setTransform(AffineTransform tx)
|
|
{
|
|
m00 = tx.m00;
|
|
m01 = tx.m01;
|
|
m02 = tx.m02;
|
|
m10 = tx.m10;
|
|
m11 = tx.m11;
|
|
m12 = tx.m12;
|
|
type = tx.type;
|
|
}
|
|
|
|
/**
|
|
* Set this transform to the given values:
|
|
* <pre>
|
|
* [ m00 m01 m02 ]
|
|
* [ m10 m11 m12 ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @param m00 the x scaling component
|
|
* @param m10 the y shearing component
|
|
* @param m01 the x shearing component
|
|
* @param m11 the y scaling component
|
|
* @param m02 the x translation component
|
|
* @param m12 the y translation component
|
|
*/
|
|
public void setTransform(double m00, double m10, double m01,
|
|
double m11, double m02, double m12)
|
|
{
|
|
this.m00 = m00;
|
|
this.m10 = m10;
|
|
this.m01 = m01;
|
|
this.m11 = m11;
|
|
this.m02 = m02;
|
|
this.m12 = m12;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Set this transform to the result of performing the original version of
|
|
* this followed by tx. This is commonly used when chaining transformations
|
|
* from one space to another. In matrix form:
|
|
* <pre>
|
|
* [ this ] = [ this ] x [ tx ]
|
|
* </pre>
|
|
*
|
|
* @param tx the transform to concatenate
|
|
* @throws NullPointerException if tx is null
|
|
* @see #preConcatenate(AffineTransform)
|
|
*/
|
|
public void concatenate(AffineTransform tx)
|
|
{
|
|
double n00 = m00 * tx.m00 + m01 * tx.m10;
|
|
double n01 = m00 * tx.m01 + m01 * tx.m11;
|
|
double n02 = m00 * tx.m02 + m01 * tx.m12 + m02;
|
|
double n10 = m10 * tx.m00 + m11 * tx.m10;
|
|
double n11 = m10 * tx.m01 + m11 * tx.m11;
|
|
double n12 = m10 * tx.m02 + m11 * tx.m12 + m12;
|
|
m00 = n00;
|
|
m01 = n01;
|
|
m02 = n02;
|
|
m10 = n10;
|
|
m11 = n11;
|
|
m12 = n12;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Set this transform to the result of performing tx followed by the
|
|
* original version of this. This is less common than normal concatenation,
|
|
* but can still be used to chain transformations from one space to another.
|
|
* In matrix form:
|
|
* <pre>
|
|
* [ this ] = [ tx ] x [ this ]
|
|
* </pre>
|
|
*
|
|
* @param tx the transform to concatenate
|
|
* @throws NullPointerException if tx is null
|
|
* @see #concatenate(AffineTransform)
|
|
*/
|
|
public void preConcatenate(AffineTransform tx)
|
|
{
|
|
double n00 = tx.m00 * m00 + tx.m01 * m10;
|
|
double n01 = tx.m00 * m01 + tx.m01 * m11;
|
|
double n02 = tx.m00 * m02 + tx.m01 * m12 + tx.m02;
|
|
double n10 = tx.m10 * m00 + tx.m11 * m10;
|
|
double n11 = tx.m10 * m01 + tx.m11 * m11;
|
|
double n12 = tx.m10 * m02 + tx.m11 * m12 + tx.m12;
|
|
m00 = n00;
|
|
m01 = n01;
|
|
m02 = n02;
|
|
m10 = n10;
|
|
m11 = n11;
|
|
m12 = n12;
|
|
updateType();
|
|
}
|
|
|
|
/**
|
|
* Returns a transform, which if concatenated to this one, will result in
|
|
* the identity transform. This is useful for undoing transformations, but
|
|
* is only possible if the original transform has an inverse (ie. does not
|
|
* map multiple points to the same line or point). A transform exists only
|
|
* if getDeterminant() has a non-zero value.
|
|
*
|
|
* The inverse is calculated as:
|
|
*
|
|
* <pre>
|
|
*
|
|
* Let A be the matrix for which we want to find the inverse:
|
|
*
|
|
* A = [ m00 m01 m02 ]
|
|
* [ m10 m11 m12 ]
|
|
* [ 0 0 1 ]
|
|
*
|
|
*
|
|
* 1
|
|
* inverse (A) = --- x adjoint(A)
|
|
* det
|
|
*
|
|
*
|
|
*
|
|
* = 1 [ m11 -m01 m01*m12-m02*m11 ]
|
|
* --- x [ -m10 m00 -m00*m12+m10*m02 ]
|
|
* det [ 0 0 m00*m11-m10*m01 ]
|
|
*
|
|
*
|
|
*
|
|
* = [ m11/det -m01/det m01*m12-m02*m11/det ]
|
|
* [ -m10/det m00/det -m00*m12+m10*m02/det ]
|
|
* [ 0 0 1 ]
|
|
*
|
|
*
|
|
* </pre>
|
|
*
|
|
*
|
|
*
|
|
* @return a new inverse transform
|
|
* @throws NoninvertibleTransformException if inversion is not possible
|
|
* @see #getDeterminant()
|
|
*/
|
|
public AffineTransform createInverse()
|
|
throws NoninvertibleTransformException
|
|
{
|
|
double det = getDeterminant();
|
|
if (det == 0)
|
|
throw new NoninvertibleTransformException("can't invert transform");
|
|
|
|
double im00 = m11 / det;
|
|
double im10 = -m10 / det;
|
|
double im01 = -m01 / det;
|
|
double im11 = m00 / det;
|
|
double im02 = (m01 * m12 - m02 * m11) / det;
|
|
double im12 = (-m00 * m12 + m10 * m02) / det;
|
|
|
|
return new AffineTransform (im00, im10, im01, im11, im02, im12);
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation on the given source point, and store the
|
|
* result in the destination (creating it if necessary). It is safe for
|
|
* src and dst to be the same.
|
|
*
|
|
* @param src the source point
|
|
* @param dst the destination, or null
|
|
* @return the transformation of src, in dst if it was non-null
|
|
* @throws NullPointerException if src is null
|
|
*/
|
|
public Point2D transform(Point2D src, Point2D dst)
|
|
{
|
|
if (dst == null)
|
|
dst = new Point2D.Double();
|
|
double x = src.getX();
|
|
double y = src.getY();
|
|
double nx = m00 * x + m01 * y + m02;
|
|
double ny = m10 * x + m11 * y + m12;
|
|
dst.setLocation(nx, ny);
|
|
return dst;
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation on an array of points, storing the results
|
|
* in another (possibly same) array. This will not create a destination
|
|
* array, but will create points for the null entries of the destination.
|
|
* The transformation is done sequentially. While having a single source
|
|
* and destination point be the same is safe, you should be aware that
|
|
* duplicate references to the same point in the source, and having the
|
|
* source overlap the destination, may result in your source points changing
|
|
* from a previous transform before it is their turn to be evaluated.
|
|
*
|
|
* @param src the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dst the array of destination points (may have null entries)
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null, or src has null
|
|
* entries
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
* @throws ArrayStoreException if new points are incompatible with dst
|
|
*/
|
|
public void transform(Point2D[] src, int srcOff,
|
|
Point2D[] dst, int dstOff, int num)
|
|
{
|
|
while (--num >= 0)
|
|
dst[dstOff] = transform(src[srcOff++], dst[dstOff++]);
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation on an array of points, in (x,y) pairs,
|
|
* storing the results in another (possibly same) array. This will not
|
|
* create a destination array. All sources are copied before the
|
|
* transformation, so that no result will overwrite a point that has not yet
|
|
* been evaluated.
|
|
*
|
|
* @param srcPts the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dstPts the array of destination points
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
*/
|
|
public void transform(float[] srcPts, int srcOff,
|
|
float[] dstPts, int dstOff, int num)
|
|
{
|
|
if (srcPts == dstPts && dstOff > srcOff
|
|
&& num > 1 && srcOff + 2 * num > dstOff)
|
|
{
|
|
float[] f = new float[2 * num];
|
|
System.arraycopy(srcPts, srcOff, f, 0, 2 * num);
|
|
srcPts = f;
|
|
}
|
|
while (--num >= 0)
|
|
{
|
|
float x = srcPts[srcOff++];
|
|
float y = srcPts[srcOff++];
|
|
dstPts[dstOff++] = (float) (m00 * x + m01 * y + m02);
|
|
dstPts[dstOff++] = (float) (m10 * x + m11 * y + m12);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation on an array of points, in (x,y) pairs,
|
|
* storing the results in another (possibly same) array. This will not
|
|
* create a destination array. All sources are copied before the
|
|
* transformation, so that no result will overwrite a point that has not yet
|
|
* been evaluated.
|
|
*
|
|
* @param srcPts the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dstPts the array of destination points
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
*/
|
|
public void transform(double[] srcPts, int srcOff,
|
|
double[] dstPts, int dstOff, int num)
|
|
{
|
|
if (srcPts == dstPts && dstOff > srcOff
|
|
&& num > 1 && srcOff + 2 * num > dstOff)
|
|
{
|
|
double[] d = new double[2 * num];
|
|
System.arraycopy(srcPts, srcOff, d, 0, 2 * num);
|
|
srcPts = d;
|
|
}
|
|
while (--num >= 0)
|
|
{
|
|
double x = srcPts[srcOff++];
|
|
double y = srcPts[srcOff++];
|
|
dstPts[dstOff++] = m00 * x + m01 * y + m02;
|
|
dstPts[dstOff++] = m10 * x + m11 * y + m12;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation on an array of points, in (x,y) pairs,
|
|
* storing the results in another array. This will not create a destination
|
|
* array.
|
|
*
|
|
* @param srcPts the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dstPts the array of destination points
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
*/
|
|
public void transform(float[] srcPts, int srcOff,
|
|
double[] dstPts, int dstOff, int num)
|
|
{
|
|
while (--num >= 0)
|
|
{
|
|
float x = srcPts[srcOff++];
|
|
float y = srcPts[srcOff++];
|
|
dstPts[dstOff++] = m00 * x + m01 * y + m02;
|
|
dstPts[dstOff++] = m10 * x + m11 * y + m12;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation on an array of points, in (x,y) pairs,
|
|
* storing the results in another array. This will not create a destination
|
|
* array.
|
|
*
|
|
* @param srcPts the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dstPts the array of destination points
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
*/
|
|
public void transform(double[] srcPts, int srcOff,
|
|
float[] dstPts, int dstOff, int num)
|
|
{
|
|
while (--num >= 0)
|
|
{
|
|
double x = srcPts[srcOff++];
|
|
double y = srcPts[srcOff++];
|
|
dstPts[dstOff++] = (float) (m00 * x + m01 * y + m02);
|
|
dstPts[dstOff++] = (float) (m10 * x + m11 * y + m12);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Perform the inverse of this transformation on the given source point,
|
|
* and store the result in the destination (creating it if necessary). It
|
|
* is safe for src and dst to be the same.
|
|
*
|
|
* @param src the source point
|
|
* @param dst the destination, or null
|
|
* @return the inverse transformation of src, in dst if it was non-null
|
|
* @throws NullPointerException if src is null
|
|
* @throws NoninvertibleTransformException if the inverse does not exist
|
|
* @see #getDeterminant()
|
|
*/
|
|
public Point2D inverseTransform(Point2D src, Point2D dst)
|
|
throws NoninvertibleTransformException
|
|
{
|
|
return createInverse().transform(src, dst);
|
|
}
|
|
|
|
/**
|
|
* Perform the inverse of this transformation on an array of points, in
|
|
* (x,y) pairs, storing the results in another (possibly same) array. This
|
|
* will not create a destination array. All sources are copied before the
|
|
* transformation, so that no result will overwrite a point that has not yet
|
|
* been evaluated.
|
|
*
|
|
* @param srcPts the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dstPts the array of destination points
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
* @throws NoninvertibleTransformException if the inverse does not exist
|
|
* @see #getDeterminant()
|
|
*/
|
|
public void inverseTransform(double[] srcPts, int srcOff,
|
|
double[] dstPts, int dstOff, int num)
|
|
throws NoninvertibleTransformException
|
|
{
|
|
createInverse().transform(srcPts, srcOff, dstPts, dstOff, num);
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation, less any translation, on the given source
|
|
* point, and store the result in the destination (creating it if
|
|
* necessary). It is safe for src and dst to be the same. The reduced
|
|
* transform is equivalent to:
|
|
* <pre>
|
|
* [ x' ] = [ m00 m01 ] [ x ] = [ m00 * x + m01 * y ]
|
|
* [ y' ] [ m10 m11 ] [ y ] = [ m10 * x + m11 * y ]
|
|
* </pre>
|
|
*
|
|
* @param src the source point
|
|
* @param dst the destination, or null
|
|
* @return the delta transformation of src, in dst if it was non-null
|
|
* @throws NullPointerException if src is null
|
|
*/
|
|
public Point2D deltaTransform(Point2D src, Point2D dst)
|
|
{
|
|
if (dst == null)
|
|
dst = new Point2D.Double();
|
|
double x = src.getX();
|
|
double y = src.getY();
|
|
double nx = m00 * x + m01 * y;
|
|
double ny = m10 * x + m11 * y;
|
|
dst.setLocation(nx, ny);
|
|
return dst;
|
|
}
|
|
|
|
/**
|
|
* Perform this transformation, less any translation, on an array of points,
|
|
* in (x,y) pairs, storing the results in another (possibly same) array.
|
|
* This will not create a destination array. All sources are copied before
|
|
* the transformation, so that no result will overwrite a point that has
|
|
* not yet been evaluated. The reduced transform is equivalent to:
|
|
* <pre>
|
|
* [ x' ] = [ m00 m01 ] [ x ] = [ m00 * x + m01 * y ]
|
|
* [ y' ] [ m10 m11 ] [ y ] = [ m10 * x + m11 * y ]
|
|
* </pre>
|
|
*
|
|
* @param srcPts the array of source points
|
|
* @param srcOff the starting offset into src
|
|
* @param dstPts the array of destination points
|
|
* @param dstOff the starting offset into dst
|
|
* @param num the number of points to transform
|
|
* @throws NullPointerException if src or dst is null
|
|
* @throws ArrayIndexOutOfBoundsException if array bounds are exceeded
|
|
*/
|
|
public void deltaTransform(double[] srcPts, int srcOff,
|
|
double[] dstPts, int dstOff,
|
|
int num)
|
|
{
|
|
if (srcPts == dstPts && dstOff > srcOff
|
|
&& num > 1 && srcOff + 2 * num > dstOff)
|
|
{
|
|
double[] d = new double[2 * num];
|
|
System.arraycopy(srcPts, srcOff, d, 0, 2 * num);
|
|
srcPts = d;
|
|
}
|
|
while (--num >= 0)
|
|
{
|
|
double x = srcPts[srcOff++];
|
|
double y = srcPts[srcOff++];
|
|
dstPts[dstOff++] = m00 * x + m01 * y;
|
|
dstPts[dstOff++] = m10 * x + m11 * y;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return a new Shape, based on the given one, where the path of the shape
|
|
* has been transformed by this transform. Notice that this uses GeneralPath,
|
|
* which only stores points in float precision.
|
|
*
|
|
* @param src the shape source to transform
|
|
* @return the shape, transformed by this, <code>null</code> if src is
|
|
* <code>null</code>.
|
|
* @see GeneralPath#transform(AffineTransform)
|
|
*/
|
|
public Shape createTransformedShape(Shape src)
|
|
{
|
|
if(src == null)
|
|
return null;
|
|
GeneralPath p = new GeneralPath(src);
|
|
p.transform(this);
|
|
return p;
|
|
}
|
|
|
|
/**
|
|
* Returns a string representation of the transform, in the format:
|
|
* <code>"AffineTransform[[" + m00 + ", " + m01 + ", " + m02 + "], ["
|
|
* + m10 + ", " + m11 + ", " + m12 + "]]"</code>.
|
|
*
|
|
* @return the string representation
|
|
*/
|
|
public String toString()
|
|
{
|
|
return "AffineTransform[[" + m00 + ", " + m01 + ", " + m02 + "], ["
|
|
+ m10 + ", " + m11 + ", " + m12 + "]]";
|
|
}
|
|
|
|
/**
|
|
* Tests if this transformation is the identity:
|
|
* <pre>
|
|
* [ 1 0 0 ]
|
|
* [ 0 1 0 ]
|
|
* [ 0 0 1 ]
|
|
* </pre>
|
|
*
|
|
* @return true if this is the identity transform
|
|
*/
|
|
public boolean isIdentity()
|
|
{
|
|
// Rather than rely on type, check explicitly.
|
|
return (m00 == 1 && m01 == 0 && m02 == 0
|
|
&& m10 == 0 && m11 == 1 && m12 == 0);
|
|
}
|
|
|
|
/**
|
|
* Create a new transform of the same run-time type, with the same
|
|
* transforming properties as this one.
|
|
*
|
|
* @return the clone
|
|
*/
|
|
public Object clone()
|
|
{
|
|
try
|
|
{
|
|
return super.clone();
|
|
}
|
|
catch (CloneNotSupportedException e)
|
|
{
|
|
throw (Error) new InternalError().initCause(e); // Impossible
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return the hashcode for this transformation. The formula is not
|
|
* documented, but appears to be the same as:
|
|
* <pre>
|
|
* long l = Double.doubleToLongBits(getScaleX());
|
|
* l = l * 31 + Double.doubleToLongBits(getShearY());
|
|
* l = l * 31 + Double.doubleToLongBits(getShearX());
|
|
* l = l * 31 + Double.doubleToLongBits(getScaleY());
|
|
* l = l * 31 + Double.doubleToLongBits(getTranslateX());
|
|
* l = l * 31 + Double.doubleToLongBits(getTranslateY());
|
|
* return (int) ((l >> 32) ^ l);
|
|
* </pre>
|
|
*
|
|
* @return the hashcode
|
|
*/
|
|
public int hashCode()
|
|
{
|
|
long l = Double.doubleToLongBits(m00);
|
|
l = l * 31 + Double.doubleToLongBits(m10);
|
|
l = l * 31 + Double.doubleToLongBits(m01);
|
|
l = l * 31 + Double.doubleToLongBits(m11);
|
|
l = l * 31 + Double.doubleToLongBits(m02);
|
|
l = l * 31 + Double.doubleToLongBits(m12);
|
|
return (int) ((l >> 32) ^ l);
|
|
}
|
|
|
|
/**
|
|
* Compares two transforms for equality. This returns true if they have the
|
|
* same matrix values.
|
|
*
|
|
* @param obj the transform to compare
|
|
* @return true if it is equal
|
|
*/
|
|
public boolean equals(Object obj)
|
|
{
|
|
if (! (obj instanceof AffineTransform))
|
|
return false;
|
|
AffineTransform t = (AffineTransform) obj;
|
|
return (m00 == t.m00 && m01 == t.m01 && m02 == t.m02
|
|
&& m10 == t.m10 && m11 == t.m11 && m12 == t.m12);
|
|
}
|
|
|
|
/**
|
|
* Helper to decode the type from the matrix. This is not guaranteed
|
|
* to find the optimal type, but at least it will be valid.
|
|
*/
|
|
private void updateType()
|
|
{
|
|
double det = getDeterminant();
|
|
if (det == 0)
|
|
{
|
|
type = TYPE_GENERAL_TRANSFORM;
|
|
return;
|
|
}
|
|
// Scale (includes rotation by PI) or translation.
|
|
if (m01 == 0 && m10 == 0)
|
|
{
|
|
if (m00 == m11)
|
|
type = m00 == 1 ? TYPE_IDENTITY : TYPE_UNIFORM_SCALE;
|
|
else
|
|
type = TYPE_GENERAL_SCALE;
|
|
if (m02 != 0 || m12 != 0)
|
|
type |= TYPE_TRANSLATION;
|
|
}
|
|
// Rotation.
|
|
else if (m00 == m11 && m01 == -m10)
|
|
{
|
|
type = m00 == 0 ? TYPE_QUADRANT_ROTATION : TYPE_GENERAL_ROTATION;
|
|
if (det != 1)
|
|
type |= TYPE_UNIFORM_SCALE;
|
|
if (m02 != 0 || m12 != 0)
|
|
type |= TYPE_TRANSLATION;
|
|
}
|
|
else
|
|
type = TYPE_GENERAL_TRANSFORM;
|
|
}
|
|
|
|
/**
|
|
* Reads a transform from an object stream.
|
|
*
|
|
* @param s the stream to read from
|
|
* @throws ClassNotFoundException if there is a problem deserializing
|
|
* @throws IOException if there is a problem deserializing
|
|
*/
|
|
private void readObject(ObjectInputStream s)
|
|
throws ClassNotFoundException, IOException
|
|
{
|
|
s.defaultReadObject();
|
|
updateType();
|
|
}
|
|
} // class AffineTransform
|