package com.himamis.retex.renderer.share.platform.graphics.stubs; /* * Copyright (c) 1996, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ import com.himamis.retex.renderer.share.platform.graphics.Transform; /** * The <code>AffineTransform</code> class represents a 2D affine transform * that performs a linear mapping from 2D coordinates to other 2D * coordinates that preserves the "straightness" and * "parallelness" of lines. Affine transformations can be constructed * using sequences of translations, scales, flips, rotations, and shears. * <p> * Such a coordinate transformation can be represented by a 3 row by * 3 column matrix with an implied last row of [ 0 0 1 ]. This matrix * transforms source coordinates {@code (x,y)} into * destination coordinates {@code (x',y')} by considering * them to be a column vector and multiplying the coordinate vector * by the matrix according to the following process: * <pre> * [ x'] [ m00 m01 m02 ] [ x ] [ m00x + m01y + m02 ] * [ y'] = [ m10 m11 m12 ] [ y ] = [ m10x + m11y + m12 ] * [ 1 ] [ 0 0 1 ] [ 1 ] [ 1 ] * </pre> * <p> * <a name="quadrantapproximation"><h4>Handling 90-Degree Rotations</h4></a> * <p> * In some variations of the <code>rotate</code> methods in the * <code>AffineTransform</code> class, a double-precision argument * specifies the angle of rotation in radians. * These methods have special handling for rotations of approximately * 90 degrees (including multiples such as 180, 270, and 360 degrees), * so that the common case of quadrant rotation is handled more * efficiently. * This special handling can cause angles very close to multiples of * 90 degrees to be treated as if they were exact multiples of * 90 degrees. * For small multiples of 90 degrees the range of angles treated * as a quadrant rotation is approximately 0.00000121 degrees wide. * This section explains why such special care is needed and how * it is implemented. * <p> * Since 90 degrees is represented as <code>PI/2</code> in radians, * and since PI is a transcendental (and therefore irrational) number, * it is not possible to exactly represent a multiple of 90 degrees as * an exact double precision value measured in radians. * As a result it is theoretically impossible to describe quadrant * rotations (90, 180, 270 or 360 degrees) using these values. * Double precision floating point values can get very close to * non-zero multiples of <code>PI/2</code> but never close enough * for the sine or cosine to be exactly 0.0, 1.0 or -1.0. * The implementations of <code>Math.sin()</code> and * <code>Math.cos()</code> correspondingly never return 0.0 * for any case other than <code>Math.sin(0.0)</code>. * These same implementations do, however, return exactly 1.0 and * -1.0 for some range of numbers around each multiple of 90 * degrees since the correct answer is so close to 1.0 or -1.0 that * the double precision significand cannot represent the difference * as accurately as it can for numbers that are near 0.0. * <p> * The net result of these issues is that if the * <code>Math.sin()</code> and <code>Math.cos()</code> methods * are used to directly generate the values for the matrix modifications * during these radian-based rotation operations then the resulting * transform is never strictly classifiable as a quadrant rotation * even for a simple case like <code>rotate(Math.PI/2.0)</code>, * due to minor variations in the matrix caused by the non-0.0 values * obtained for the sine and cosine. * If these transforms are not classified as quadrant rotations then * subsequent code which attempts to optimize further operations based * upon the type of the transform will be relegated to its most general * implementation. * <p> * Because quadrant rotations are fairly common, * this class should handle these cases reasonably quickly, both in * applying the rotations to the transform and in applying the resulting * transform to the coordinates. * To facilitate this optimal handling, the methods which take an angle * of rotation measured in radians attempt to detect angles that are * intended to be quadrant rotations and treat them as such. * These methods therefore treat an angle <em>theta</em> as a quadrant * rotation if either <code>Math.sin(<em>theta</em>)</code> or * <code>Math.cos(<em>theta</em>)</code> returns exactly 1.0 or -1.0. * As a rule of thumb, this property holds true for a range of * approximately 0.0000000211 radians (or 0.00000121 degrees) around * small multiples of <code>Math.PI/2.0</code>. * * @author Jim Graham * @since 1.2 */ public class AffineTransform implements Transform { /* * This constant is only useful for the cached type field. * It indicates that the type has been decached and must be recalculated. */ private static final int TYPE_UNKNOWN = -1; /** * This constant indicates that the transform defined by this object * is an identity transform. * An identity transform is one in which the output coordinates are * always the same as the input coordinates. * If this transform is anything other than the identity transform, * the type will either be the constant GENERAL_TRANSFORM or a * combination of the appropriate flag bits for the various coordinate * conversions that this transform performs. * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_IDENTITY = 0; /** * This flag bit indicates that the transform defined by this object * performs a translation in addition to the conversions indicated * by other flag bits. * A translation moves the coordinates by a constant amount in x * and y without changing the length or angle of vectors. * @see #TYPE_IDENTITY * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_TRANSLATION = 1; /** * This flag bit indicates that the transform defined by this object * performs a uniform scale in addition to the conversions indicated * by other flag bits. * A uniform scale multiplies the length of vectors by the same amount * in both the x and y directions without changing the angle between * vectors. * This flag bit is mutually exclusive with the TYPE_GENERAL_SCALE flag. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_UNIFORM_SCALE = 2; /** * This flag bit indicates that the transform defined by this object * performs a general scale in addition to the conversions indicated * by other flag bits. * A general scale multiplies the length of vectors by different * amounts in the x and y directions without changing the angle * between perpendicular vectors. * This flag bit is mutually exclusive with the TYPE_UNIFORM_SCALE flag. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_GENERAL_SCALE = 4; /** * This constant is a bit mask for any of the scale flag bits. * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @since 1.2 */ public static final int TYPE_MASK_SCALE = (TYPE_UNIFORM_SCALE | TYPE_GENERAL_SCALE); /** * This flag bit indicates that the transform defined by this object * performs a mirror image flip about some axis which changes the * normally right handed coordinate system into a left handed * system in addition to the conversions indicated by other flag bits. * A right handed coordinate system is one where the positive X * axis rotates counterclockwise to overlay the positive Y axis * similar to the direction that the fingers on your right hand * curl when you stare end on at your thumb. * A left handed coordinate system is one where the positive X * axis rotates clockwise to overlay the positive Y axis similar * to the direction that the fingers on your left hand curl. * There is no mathematical way to determine the angle of the * original flipping or mirroring transformation since all angles * of flip are identical given an appropriate adjusting rotation. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_FLIP = 64; /* NOTE: TYPE_FLIP was added after GENERAL_TRANSFORM was in public * circulation and the flag bits could no longer be conveniently * renumbered without introducing binary incompatibility in outside * code. */ /** * This flag bit indicates that the transform defined by this object * performs a quadrant rotation by some multiple of 90 degrees in * addition to the conversions indicated by other flag bits. * A rotation changes the angles of vectors by the same amount * regardless of the original direction of the vector and without * changing the length of the vector. * This flag bit is mutually exclusive with the TYPE_GENERAL_ROTATION flag. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_QUADRANT_ROTATION = 8; /** * This flag bit indicates that the transform defined by this object * performs a rotation by an arbitrary angle in addition to the * conversions indicated by other flag bits. * A rotation changes the angles of vectors by the same amount * regardless of the original direction of the vector and without * changing the length of the vector. * This flag bit is mutually exclusive with the * TYPE_QUADRANT_ROTATION flag. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #getType * @since 1.2 */ public static final int TYPE_GENERAL_ROTATION = 16; /** * This constant is a bit mask for any of the rotation flag bits. * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @since 1.2 */ public static final int TYPE_MASK_ROTATION = (TYPE_QUADRANT_ROTATION | TYPE_GENERAL_ROTATION); /** * This constant indicates that the transform defined by this object * performs an arbitrary conversion of the input coordinates. * If this transform can be classified by any of the above constants, * the type will either be the constant TYPE_IDENTITY or a * combination of the appropriate flag bits for the various coordinate * conversions that this transform performs. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #getType * @since 1.2 */ public static final int TYPE_GENERAL_TRANSFORM = 32; /** * This constant is used for the internal state variable to indicate * that no calculations need to be performed and that the source * coordinates only need to be copied to their destinations to * complete the transformation equation of this transform. * @see #APPLY_TRANSLATE * @see #APPLY_SCALE * @see #APPLY_SHEAR * @see #state */ static final int APPLY_IDENTITY = 0; /** * This constant is used for the internal state variable to indicate * that the translation components of the matrix (m02 and m12) need * to be added to complete the transformation equation of this transform. * @see #APPLY_IDENTITY * @see #APPLY_SCALE * @see #APPLY_SHEAR * @see #state */ static final int APPLY_TRANSLATE = 1; /** * This constant is used for the internal state variable to indicate * that the scaling components of the matrix (m00 and m11) need * to be factored in to complete the transformation equation of * this transform. If the APPLY_SHEAR bit is also set then it * indicates that the scaling components are not both 0.0. If the * APPLY_SHEAR bit is not also set then it indicates that the * scaling components are not both 1.0. If neither the APPLY_SHEAR * nor the APPLY_SCALE bits are set then the scaling components * are both 1.0, which means that the x and y components contribute * to the transformed coordinate, but they are not multiplied by * any scaling factor. * @see #APPLY_IDENTITY * @see #APPLY_TRANSLATE * @see #APPLY_SHEAR * @see #state */ static final int APPLY_SCALE = 2; /** * This constant is used for the internal state variable to indicate * that the shearing components of the matrix (m01 and m10) need * to be factored in to complete the transformation equation of this * transform. The presence of this bit in the state variable changes * the interpretation of the APPLY_SCALE bit as indicated in its * documentation. * @see #APPLY_IDENTITY * @see #APPLY_TRANSLATE * @see #APPLY_SCALE * @see #state */ static final int APPLY_SHEAR = 4; /* * For methods which combine together the state of two separate * transforms and dispatch based upon the combination, these constants * specify how far to shift one of the states so that the two states * are mutually non-interfering and provide constants for testing the * bits of the shifted (HI) state. The methods in this class use * the convention that the state of "this" transform is unshifted and * the state of the "other" or "argument" transform is shifted (HI). */ // private static final int HI_SHIFT = 3; // private static final int HI_IDENTITY = APPLY_IDENTITY << HI_SHIFT; // private static final int HI_TRANSLATE = APPLY_TRANSLATE << HI_SHIFT; // private static final int HI_SCALE = APPLY_SCALE << HI_SHIFT; // private static final int HI_SHEAR = APPLY_SHEAR << HI_SHIFT; /** * The X coordinate scaling element of the 3x3 * affine transformation matrix. * * */ double m00; /** * The Y coordinate shearing element of the 3x3 * affine transformation matrix. * * */ double m10; /** * The X coordinate shearing element of the 3x3 * affine transformation matrix. * * */ double m01; /** * The Y coordinate scaling element of the 3x3 * affine transformation matrix. * * */ double m11; /** * The X coordinate of the translation element of the * 3x3 affine transformation matrix. * * */ double m02; /** * The Y coordinate of the translation element of the * 3x3 affine transformation matrix. * * */ double m12; /** * This field keeps track of which components of the matrix need to * be applied when performing a transformation. * @see #APPLY_IDENTITY * @see #APPLY_TRANSLATE * @see #APPLY_SCALE * @see #APPLY_SHEAR */ transient int state; /** * This field caches the current transformation type of the matrix. * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_FLIP * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @see #TYPE_UNKNOWN * @see #getType */ private transient int type; /** * Constructs a new <code>AffineTransform</code> representing the * Identity transformation. * @since 1.2 */ public AffineTransform() { m00 = m11 = 1.0; // m01 = m10 = m02 = m12 = 0.0; /* Not needed. */ // state = APPLY_IDENTITY; /* Not needed. */ // type = TYPE_IDENTITY; /* Not needed. */ } /** * Constructs a new <code>AffineTransform</code> that is a copy of * the specified <code>AffineTransform</code> object. * @param Tx the <code>AffineTransform</code> object to copy * @since 1.2 */ public AffineTransform(AffineTransform Tx) { this.m00 = Tx.m00; this.m10 = Tx.m10; this.m01 = Tx.m01; this.m11 = Tx.m11; this.m02 = Tx.m02; this.m12 = Tx.m12; this.state = Tx.state; this.type = Tx.type; } /** * Constructs a new <code>AffineTransform</code> from 6 double * precision values representing the 6 specifiable entries of the 3x3 * transformation matrix. * * @param m00 the X coordinate scaling element of the 3x3 matrix * @param m10 the Y coordinate shearing element of the 3x3 matrix * @param m01 the X coordinate shearing element of the 3x3 matrix * @param m11 the Y coordinate scaling element of the 3x3 matrix * @param m02 the X coordinate translation element of the 3x3 matrix * @param m12 the Y coordinate translation element of the 3x3 matrix * @since 1.2 */ public AffineTransform(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; updateState(); } /** * Constructs a new <code>AffineTransform</code> from an array of * double precision values representing either the 4 non-translation * entries or the 6 specifiable entries of the 3x3 transformation * matrix. The values are retrieved from the array as * { m00 m10 m01 m11 [m02 m12]}. * @param flatmatrix the double array containing the values to be set * in the new <code>AffineTransform</code> object. The length of the * array is assumed to be at least 4. If the length of the array is * less than 6, only the first 4 values are taken. If the length of * the array is greater than 6, the first 6 values are taken. * @since 1.2 */ public AffineTransform(double[] flatmatrix) { m00 = flatmatrix[0]; m10 = flatmatrix[1]; m01 = flatmatrix[2]; m11 = flatmatrix[3]; if (flatmatrix.length > 5) { m02 = flatmatrix[4]; m12 = flatmatrix[5]; } updateState(); } /** * Returns a transform representing a translation transformation. * The matrix representing the returned transform is: * <pre> * [ 1 0 tx ] * [ 0 1 ty ] * [ 0 0 1 ] * </pre> * @param tx the distance by which coordinates are translated in the * X axis direction * @param ty the distance by which coordinates are translated in the * Y axis direction * @return an <code>AffineTransform</code> object that represents a * translation transformation, created with the specified vector. * @since 1.2 */ public static AffineTransform getTranslateInstance(double tx, double ty) { AffineTransform Tx = new AffineTransform(); Tx.setToTranslation(tx, ty); return Tx; } /** * Returns a transform representing a rotation transformation. * The matrix representing the returned transform is: * <pre> * [ cos(theta) -sin(theta) 0 ] * [ sin(theta) cos(theta) 0 ] * [ 0 0 1 ] * </pre> * Rotating by a positive angle theta rotates points on the positive * X axis toward the positive Y axis. * Note also the discussion of * <a href="#quadrantapproximation">Handling 90-Degree Rotations</a> * above. * @param theta the angle of rotation measured in radians * @return an <code>AffineTransform</code> object that is a rotation * transformation, created with the specified angle of rotation. * @since 1.2 */ public static AffineTransform getRotateInstance(double theta) { AffineTransform Tx = new AffineTransform(); Tx.setToRotation(theta); return Tx; } /** * Returns a transform that rotates coordinates around an anchor point. * This operation is equivalent to translating the coordinates so * that the anchor point is at the origin (S1), then rotating them * about the new origin (S2), and finally translating so that the * intermediate origin is restored to the coordinates of the original * anchor point (S3). * <p> * This operation is equivalent to the following sequence of calls: * <pre> * AffineTransform Tx = new AffineTransform(); * Tx.translate(anchorx, anchory); // S3: final translation * Tx.rotate(theta); // S2: rotate around anchor * Tx.translate(-anchorx, -anchory); // S1: translate anchor to origin * </pre> * The matrix representing the returned transform is: * <pre> * [ cos(theta) -sin(theta) x-x*cos+y*sin ] * [ sin(theta) cos(theta) y-x*sin-y*cos ] * [ 0 0 1 ] * </pre> * Rotating by a positive angle theta rotates points on the positive * X axis toward the positive Y axis. * Note also the discussion of * <a href="#quadrantapproximation">Handling 90-Degree Rotations</a> * above. * * @param theta the angle of rotation measured in radians * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @return an <code>AffineTransform</code> object that rotates * coordinates around the specified point by the specified angle of * rotation. * @since 1.2 */ public static AffineTransform getRotateInstance(double theta, double anchorx, double anchory) { AffineTransform Tx = new AffineTransform(); Tx.setToRotation(theta, anchorx, anchory); return Tx; } /** * Returns a transform that rotates coordinates according to * a rotation vector. * All coordinates rotate about the origin by the same amount. * The amount of rotation is such that coordinates along the former * positive X axis will subsequently align with the vector pointing * from the origin to the specified vector coordinates. * If both <code>vecx</code> and <code>vecy</code> are 0.0, * an identity transform is returned. * This operation is equivalent to calling: * <pre> * AffineTransform.getRotateInstance(Math.atan2(vecy, vecx)); * </pre> * * @param vecx the X coordinate of the rotation vector * @param vecy the Y coordinate of the rotation vector * @return an <code>AffineTransform</code> object that rotates * coordinates according to the specified rotation vector. * @since 1.6 */ public static AffineTransform getRotateInstance(double vecx, double vecy) { AffineTransform Tx = new AffineTransform(); Tx.setToRotation(vecx, vecy); return Tx; } /** * Returns a transform that rotates coordinates around an anchor * point accordinate to a rotation vector. * All coordinates rotate about the specified anchor coordinates * by the same amount. * The amount of rotation is such that coordinates along the former * positive X axis will subsequently align with the vector pointing * from the origin to the specified vector coordinates. * If both <code>vecx</code> and <code>vecy</code> are 0.0, * an identity transform is returned. * This operation is equivalent to calling: * <pre> * AffineTransform.getRotateInstance(Math.atan2(vecy, vecx), * anchorx, anchory); * </pre> * * @param vecx the X coordinate of the rotation vector * @param vecy the Y coordinate of the rotation vector * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @return an <code>AffineTransform</code> object that rotates * coordinates around the specified point according to the * specified rotation vector. * @since 1.6 */ public static AffineTransform getRotateInstance(double vecx, double vecy, double anchorx, double anchory) { AffineTransform Tx = new AffineTransform(); Tx.setToRotation(vecx, vecy, anchorx, anchory); return Tx; } /** * Returns a transform that rotates coordinates by the specified * number of quadrants. * This operation is equivalent to calling: * <pre> * AffineTransform.getRotateInstance(numquadrants * Math.PI / 2.0); * </pre> * Rotating by a positive number of quadrants rotates points on * the positive X axis toward the positive Y axis. * @param numquadrants the number of 90 degree arcs to rotate by * @return an <code>AffineTransform</code> object that rotates * coordinates by the specified number of quadrants. * @since 1.6 */ public static AffineTransform getQuadrantRotateInstance(int numquadrants) { AffineTransform Tx = new AffineTransform(); Tx.setToQuadrantRotation(numquadrants); return Tx; } /** * Returns a transform that rotates coordinates by the specified * number of quadrants around the specified anchor point. * This operation is equivalent to calling: * <pre> * AffineTransform.getRotateInstance(numquadrants * Math.PI / 2.0, * anchorx, anchory); * </pre> * Rotating by a positive number of quadrants rotates points on * the positive X axis toward the positive Y axis. * * @param numquadrants the number of 90 degree arcs to rotate by * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @return an <code>AffineTransform</code> object that rotates * coordinates by the specified number of quadrants around the * specified anchor point. * @since 1.6 */ public static AffineTransform getQuadrantRotateInstance(int numquadrants, double anchorx, double anchory) { AffineTransform Tx = new AffineTransform(); Tx.setToQuadrantRotation(numquadrants, anchorx, anchory); return Tx; } /** * Returns a transform representing a scaling transformation. * The matrix representing the returned transform is: * <pre> * [ sx 0 0 ] * [ 0 sy 0 ] * [ 0 0 1 ] * </pre> * @param sx the factor by which coordinates are scaled along the * X axis direction * @param sy the factor by which coordinates are scaled along the * Y axis direction * @return an <code>AffineTransform</code> object that scales * coordinates by the specified factors. * @since 1.2 */ public static AffineTransform getScaleInstance(double sx, double sy) { AffineTransform Tx = new AffineTransform(); Tx.setToScale(sx, sy); return Tx; } /** * Returns a transform representing a shearing transformation. * The matrix representing the returned transform is: * <pre> * [ 1 shx 0 ] * [ shy 1 0 ] * [ 0 0 1 ] * </pre> * @param shx the multiplier by which coordinates are shifted in the * direction of the positive X axis as a factor of their Y coordinate * @param shy the multiplier by which coordinates are shifted in the * direction of the positive Y axis as a factor of their X coordinate * @return an <code>AffineTransform</code> object that shears * coordinates by the specified multipliers. * @since 1.2 */ public static AffineTransform getShearInstance(double shx, double shy) { AffineTransform Tx = new AffineTransform(); Tx.setToShear(shx, shy); return Tx; } /** * Retrieves the flag bits describing the conversion properties of * this transform. * The return value is either one of the constants TYPE_IDENTITY * or TYPE_GENERAL_TRANSFORM, or a combination of the * appriopriate flag bits. * A valid combination of flag bits is an exclusive OR operation * that can combine * the TYPE_TRANSLATION flag bit * in addition to either of the * TYPE_UNIFORM_SCALE or TYPE_GENERAL_SCALE flag bits * as well as either of the * TYPE_QUADRANT_ROTATION or TYPE_GENERAL_ROTATION flag bits. * @return the OR combination of any of the indicated flags that * apply to this transform * @see #TYPE_IDENTITY * @see #TYPE_TRANSLATION * @see #TYPE_UNIFORM_SCALE * @see #TYPE_GENERAL_SCALE * @see #TYPE_QUADRANT_ROTATION * @see #TYPE_GENERAL_ROTATION * @see #TYPE_GENERAL_TRANSFORM * @since 1.2 */ public int getType() { if (type == TYPE_UNKNOWN) { calculateType(); } return type; } /** * This is the utility function to calculate the flag bits when * they have not been cached. * @see #getType */ private void calculateType() { int ret = TYPE_IDENTITY; boolean sgn0, sgn1; double M0, M1, M2, M3; updateState(); switch (state) { default: stateError(); /* NOTREACHED */ //$FALL-THROUGH$ case (APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE): ret = TYPE_TRANSLATION; //$FALL-THROUGH$ case (APPLY_SHEAR | APPLY_SCALE): if ((M0 = m00) * (M2 = m01) + (M3 = m10) * (M1 = m11) != 0) { // Transformed unit vectors are not perpendicular... this.type = TYPE_GENERAL_TRANSFORM; return; } sgn0 = (M0 >= 0.0); sgn1 = (M1 >= 0.0); if (sgn0 == sgn1) { // sgn(M0) == sgn(M1) therefore sgn(M2) == -sgn(M3) // This is the "unflipped" (right-handed) state if (M0 != M1 || M2 != -M3) { ret |= (TYPE_GENERAL_ROTATION | TYPE_GENERAL_SCALE); } else if (M0 * M1 - M2 * M3 != 1.0) { ret |= (TYPE_GENERAL_ROTATION | TYPE_UNIFORM_SCALE); } else { ret |= TYPE_GENERAL_ROTATION; } } else { // sgn(M0) == -sgn(M1) therefore sgn(M2) == sgn(M3) // This is the "flipped" (left-handed) state if (M0 != -M1 || M2 != M3) { ret |= (TYPE_GENERAL_ROTATION | TYPE_FLIP | TYPE_GENERAL_SCALE); } else if (M0 * M1 - M2 * M3 != 1.0) { ret |= (TYPE_GENERAL_ROTATION | TYPE_FLIP | TYPE_UNIFORM_SCALE); } else { ret |= (TYPE_GENERAL_ROTATION | TYPE_FLIP); } } break; case (APPLY_SHEAR | APPLY_TRANSLATE): ret = TYPE_TRANSLATION; //$FALL-THROUGH$ case (APPLY_SHEAR): sgn0 = ((M0 = m01) >= 0.0); sgn1 = ((M1 = m10) >= 0.0); if (sgn0 != sgn1) { // Different signs - simple 90 degree rotation if (M0 != -M1) { ret |= (TYPE_QUADRANT_ROTATION | TYPE_GENERAL_SCALE); } else if (M0 != 1.0 && M0 != -1.0) { ret |= (TYPE_QUADRANT_ROTATION | TYPE_UNIFORM_SCALE); } else { ret |= TYPE_QUADRANT_ROTATION; } } else { // Same signs - 90 degree rotation plus an axis flip too if (M0 == M1) { ret |= (TYPE_QUADRANT_ROTATION | TYPE_FLIP | TYPE_UNIFORM_SCALE); } else { ret |= (TYPE_QUADRANT_ROTATION | TYPE_FLIP | TYPE_GENERAL_SCALE); } } break; case (APPLY_SCALE | APPLY_TRANSLATE): ret = TYPE_TRANSLATION; //$FALL-THROUGH$ //$FALL-THROUGH$ case (APPLY_SCALE): sgn0 = ((M0 = m00) >= 0.0); sgn1 = ((M1 = m11) >= 0.0); if (sgn0 == sgn1) { if (sgn0) { // Both scaling factors non-negative - simple scale // Note: APPLY_SCALE implies M0, M1 are not both 1 if (M0 == M1) { ret |= TYPE_UNIFORM_SCALE; } else { ret |= TYPE_GENERAL_SCALE; } } else { // Both scaling factors negative - 180 degree rotation if (M0 != M1) { ret |= (TYPE_QUADRANT_ROTATION | TYPE_GENERAL_SCALE); } else if (M0 != -1.0) { ret |= (TYPE_QUADRANT_ROTATION | TYPE_UNIFORM_SCALE); } else { ret |= TYPE_QUADRANT_ROTATION; } } } else { // Scaling factor signs different - flip about some axis if (M0 == -M1) { if (M0 == 1.0 || M0 == -1.0) { ret |= TYPE_FLIP; } else { ret |= (TYPE_FLIP | TYPE_UNIFORM_SCALE); } } else { ret |= (TYPE_FLIP | TYPE_GENERAL_SCALE); } } break; case (APPLY_TRANSLATE): ret = TYPE_TRANSLATION; break; case (APPLY_IDENTITY): break; } this.type = ret; } /** * Manually recalculates the state of the transform when the matrix * changes too much to predict the effects on the state. * The following table specifies what the various settings of the * state field say about the values of the corresponding matrix * element fields. * Note that the rules governing the SCALE fields are slightly * different depending on whether the SHEAR flag is also set. * <pre> * SCALE SHEAR TRANSLATE * m00/m11 m01/m10 m02/m12 * * IDENTITY 1.0 0.0 0.0 * TRANSLATE (TR) 1.0 0.0 not both 0.0 * SCALE (SC) not both 1.0 0.0 0.0 * TR | SC not both 1.0 0.0 not both 0.0 * SHEAR (SH) 0.0 not both 0.0 0.0 * TR | SH 0.0 not both 0.0 not both 0.0 * SC | SH not both 0.0 not both 0.0 0.0 * TR | SC | SH not both 0.0 not both 0.0 not both 0.0 * </pre> */ void updateState() { if (m01 == 0.0 && m10 == 0.0) { if (m00 == 1.0 && m11 == 1.0) { if (m02 == 0.0 && m12 == 0.0) { state = APPLY_IDENTITY; type = TYPE_IDENTITY; } else { state = APPLY_TRANSLATE; type = TYPE_TRANSLATION; } } else { if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SCALE; type = TYPE_UNKNOWN; } else { state = (APPLY_SCALE | APPLY_TRANSLATE); type = TYPE_UNKNOWN; } } } else { if (m00 == 0.0 && m11 == 0.0) { if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SHEAR; type = TYPE_UNKNOWN; } else { state = (APPLY_SHEAR | APPLY_TRANSLATE); type = TYPE_UNKNOWN; } } else { if (m02 == 0.0 && m12 == 0.0) { state = (APPLY_SHEAR | APPLY_SCALE); type = TYPE_UNKNOWN; } else { state = (APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE); type = TYPE_UNKNOWN; } } } } /* * Convenience method used internally to throw exceptions when * a case was forgotten in a switch statement. */ private static void stateError() { throw new RuntimeException("missing case in transform state switch"); } /** * Retrieves the 6 specifiable values in the 3x3 affine transformation * matrix and places them into an array of double precisions values. * The values are stored in the array as * { m00 m10 m01 m11 m02 m12 }. * An array of 4 doubles can also be specified, in which case only the * first four elements representing the non-transform * parts of the array are retrieved and the values are stored into * the array as { m00 m10 m01 m11 } * @param flatmatrix the double array used to store the returned * values. * @see #getScaleX * @see #getScaleY * @see #getShearX * @see #getShearY * @see #getTranslateX * @see #getTranslateY * @since 1.2 */ public void getMatrix(double[] flatmatrix) { flatmatrix[0] = m00; flatmatrix[1] = m10; flatmatrix[2] = m01; flatmatrix[3] = m11; if (flatmatrix.length > 5) { flatmatrix[4] = m02; flatmatrix[5] = m12; } } /** * Returns the X coordinate scaling element (m00) of the 3x3 * affine transformation matrix. * @return a double value that is the X coordinate of the scaling * element of the affine transformation matrix. * @see #getMatrix * @since 1.2 */ @Override public double getScaleX() { return m00; } /** * Returns the Y coordinate scaling element (m11) of the 3x3 * affine transformation matrix. * @return a double value that is the Y coordinate of the scaling * element of the affine transformation matrix. * @see #getMatrix * @since 1.2 */ @Override public double getScaleY() { return m11; } /** * Returns the X coordinate shearing element (m01) of the 3x3 * affine transformation matrix. * @return a double value that is the X coordinate of the shearing * element of the affine transformation matrix. * @see #getMatrix * @since 1.2 */ @Override public double getShearX() { return m01; } /** * Returns the Y coordinate shearing element (m10) of the 3x3 * affine transformation matrix. * @return a double value that is the Y coordinate of the shearing * element of the affine transformation matrix. * @see #getMatrix * @since 1.2 */ @Override public double getShearY() { return m10; } /** * Returns the X coordinate of the translation element (m02) of the * 3x3 affine transformation matrix. * @return a double value that is the X coordinate of the translation * element of the affine transformation matrix. * @see #getMatrix * @since 1.2 */ @Override public double getTranslateX() { return m02; } /** * Returns the Y coordinate of the translation element (m12) of the * 3x3 affine transformation matrix. * @return a double value that is the Y coordinate of the translation * element of the affine transformation matrix. * @see #getMatrix * @since 1.2 */ @Override public double getTranslateY() { return m12; } /** * Concatenates this transform with a translation transformation. * This is equivalent to calling concatenate(T), where T is an * <code>AffineTransform</code> represented by the following matrix: * <pre> * [ 1 0 tx ] * [ 0 1 ty ] * [ 0 0 1 ] * </pre> * @param tx the distance by which coordinates are translated in the * X axis direction * @param ty the distance by which coordinates are translated in the * Y axis direction * @since 1.2 */ @Override public void translate(double tx, double ty) { switch (state) { default: stateError(); /* NOTREACHED */ //$FALL-THROUGH$ case (APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE): m02 = tx * m00 + ty * m01 + m02; m12 = tx * m10 + ty * m11 + m12; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SHEAR | APPLY_SCALE; if (type != TYPE_UNKNOWN) { type -= TYPE_TRANSLATION; } } return; case (APPLY_SHEAR | APPLY_SCALE): m02 = tx * m00 + ty * m01; m12 = tx * m10 + ty * m11; if (m02 != 0.0 || m12 != 0.0) { state = APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE; type |= TYPE_TRANSLATION; } return; case (APPLY_SHEAR | APPLY_TRANSLATE): m02 = ty * m01 + m02; m12 = tx * m10 + m12; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SHEAR; if (type != TYPE_UNKNOWN) { type -= TYPE_TRANSLATION; } } return; case (APPLY_SHEAR): m02 = ty * m01; m12 = tx * m10; if (m02 != 0.0 || m12 != 0.0) { state = APPLY_SHEAR | APPLY_TRANSLATE; type |= TYPE_TRANSLATION; } return; case (APPLY_SCALE | APPLY_TRANSLATE): m02 = tx * m00 + m02; m12 = ty * m11 + m12; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SCALE; if (type != TYPE_UNKNOWN) { type -= TYPE_TRANSLATION; } } return; case (APPLY_SCALE): m02 = tx * m00; m12 = ty * m11; if (m02 != 0.0 || m12 != 0.0) { state = APPLY_SCALE | APPLY_TRANSLATE; type |= TYPE_TRANSLATION; } return; case (APPLY_TRANSLATE): m02 = tx + m02; m12 = ty + m12; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_IDENTITY; type = TYPE_IDENTITY; } return; case (APPLY_IDENTITY): m02 = tx; m12 = ty; if (tx != 0.0 || ty != 0.0) { state = APPLY_TRANSLATE; type = TYPE_TRANSLATION; } return; } } // Utility methods to optimize rotate methods. // These tables translate the flags during predictable quadrant // rotations where the shear and scale values are swapped and negated. private static final int rot90conversion[] = { /* IDENTITY => */ APPLY_SHEAR, /* TRANSLATE (TR) => */ APPLY_SHEAR | APPLY_TRANSLATE, /* SCALE (SC) => */ APPLY_SHEAR, /* SC | TR => */ APPLY_SHEAR | APPLY_TRANSLATE, /* SHEAR (SH) => */ APPLY_SCALE, /* SH | TR => */ APPLY_SCALE | APPLY_TRANSLATE, /* SH | SC => */ APPLY_SHEAR | APPLY_SCALE, /* SH | SC | TR => */ APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE, }; private final void rotate90() { double M0 = m00; m00 = m01; m01 = -M0; M0 = m10; m10 = m11; m11 = -M0; int state = rot90conversion[this.state]; if ((state & (APPLY_SHEAR | APPLY_SCALE)) == APPLY_SCALE && m00 == 1.0 && m11 == 1.0) { state -= APPLY_SCALE; } this.state = state; type = TYPE_UNKNOWN; } private final void rotate180() { m00 = -m00; m11 = -m11; int state = this.state; if ((state & (APPLY_SHEAR)) != 0) { // If there was a shear, then this rotation has no // effect on the state. m01 = -m01; m10 = -m10; } else { // No shear means the SCALE state may toggle when // m00 and m11 are negated. if (m00 == 1.0 && m11 == 1.0) { this.state = state & ~APPLY_SCALE; } else { this.state = state | APPLY_SCALE; } } type = TYPE_UNKNOWN; } private final void rotate270() { double M0 = m00; m00 = -m01; m01 = M0; M0 = m10; m10 = -m11; m11 = M0; int state = rot90conversion[this.state]; if ((state & (APPLY_SHEAR | APPLY_SCALE)) == APPLY_SCALE && m00 == 1.0 && m11 == 1.0) { state -= APPLY_SCALE; } this.state = state; type = TYPE_UNKNOWN; } /** * Concatenates this transform with a rotation transformation. * This is equivalent to calling concatenate(R), where R is an * <code>AffineTransform</code> represented by the following matrix: * <pre> * [ cos(theta) -sin(theta) 0 ] * [ sin(theta) cos(theta) 0 ] * [ 0 0 1 ] * </pre> * Rotating by a positive angle theta rotates points on the positive * X axis toward the positive Y axis. * Note also the discussion of * <a href="#quadrantapproximation">Handling 90-Degree Rotations</a> * above. * @param theta the angle of rotation measured in radians * @since 1.2 */ public void rotate(double theta) { double sin = Math.sin(theta); if (sin == 1.0) { rotate90(); } else if (sin == -1.0) { rotate270(); } else { double cos = Math.cos(theta); if (cos == -1.0) { rotate180(); } else if (cos != 1.0) { double M0, M1; M0 = m00; M1 = m01; m00 = cos * M0 + sin * M1; m01 = -sin * M0 + cos * M1; M0 = m10; M1 = m11; m10 = cos * M0 + sin * M1; m11 = -sin * M0 + cos * M1; updateState(); } } } /** * Concatenates this transform with a transform that rotates * coordinates around an anchor point. * This operation is equivalent to translating the coordinates so * that the anchor point is at the origin (S1), then rotating them * about the new origin (S2), and finally translating so that the * intermediate origin is restored to the coordinates of the original * anchor point (S3). * <p> * This operation is equivalent to the following sequence of calls: * <pre> * translate(anchorx, anchory); // S3: final translation * rotate(theta); // S2: rotate around anchor * translate(-anchorx, -anchory); // S1: translate anchor to origin * </pre> * Rotating by a positive angle theta rotates points on the positive * X axis toward the positive Y axis. * Note also the discussion of * <a href="#quadrantapproximation">Handling 90-Degree Rotations</a> * above. * * @param theta the angle of rotation measured in radians * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @since 1.2 */ public void rotate(double theta, double anchorx, double anchory) { // REMIND: Simple for now - optimize later translate(anchorx, anchory); rotate(theta); translate(-anchorx, -anchory); } /** * Concatenates this transform with a transform that rotates * coordinates according to a rotation vector. * All coordinates rotate about the origin by the same amount. * The amount of rotation is such that coordinates along the former * positive X axis will subsequently align with the vector pointing * from the origin to the specified vector coordinates. * If both <code>vecx</code> and <code>vecy</code> are 0.0, * no additional rotation is added to this transform. * This operation is equivalent to calling: * <pre> * rotate(Math.atan2(vecy, vecx)); * </pre> * * @param vecx the X coordinate of the rotation vector * @param vecy the Y coordinate of the rotation vector * @since 1.6 */ public void rotate(double vecx, double vecy) { if (vecy == 0.0) { if (vecx < 0.0) { rotate180(); } // If vecx > 0.0 - no rotation // If vecx == 0.0 - undefined rotation - treat as no rotation } else if (vecx == 0.0) { if (vecy > 0.0) { rotate90(); } else { // vecy must be < 0.0 rotate270(); } } else { double len = Math.sqrt(vecx * vecx + vecy * vecy); double sin = vecy / len; double cos = vecx / len; double M0, M1; M0 = m00; M1 = m01; m00 = cos * M0 + sin * M1; m01 = -sin * M0 + cos * M1; M0 = m10; M1 = m11; m10 = cos * M0 + sin * M1; m11 = -sin * M0 + cos * M1; updateState(); } } /** * Concatenates this transform with a transform that rotates * coordinates around an anchor point according to a rotation * vector. * All coordinates rotate about the specified anchor coordinates * by the same amount. * The amount of rotation is such that coordinates along the former * positive X axis will subsequently align with the vector pointing * from the origin to the specified vector coordinates. * If both <code>vecx</code> and <code>vecy</code> are 0.0, * the transform is not modified in any way. * This method is equivalent to calling: * <pre> * rotate(Math.atan2(vecy, vecx), anchorx, anchory); * </pre> * * @param vecx the X coordinate of the rotation vector * @param vecy the Y coordinate of the rotation vector * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @since 1.6 */ public void rotate(double vecx, double vecy, double anchorx, double anchory) { // REMIND: Simple for now - optimize later translate(anchorx, anchory); rotate(vecx, vecy); translate(-anchorx, -anchory); } /** * Concatenates this transform with a transform that rotates * coordinates by the specified number of quadrants. * This is equivalent to calling: * <pre> * rotate(numquadrants * Math.PI / 2.0); * </pre> * Rotating by a positive number of quadrants rotates points on * the positive X axis toward the positive Y axis. * @param numquadrants the number of 90 degree arcs to rotate by * @since 1.6 */ public void quadrantRotate(int numquadrants) { switch (numquadrants & 3) { case 0: break; case 1: rotate90(); break; case 2: rotate180(); break; case 3: rotate270(); break; } } /** * Concatenates this transform with a transform that rotates * coordinates by the specified number of quadrants around * the specified anchor point. * This method is equivalent to calling: * <pre> * rotate(numquadrants * Math.PI / 2.0, anchorx, anchory); * </pre> * Rotating by a positive number of quadrants rotates points on * the positive X axis toward the positive Y axis. * * @param numquadrants the number of 90 degree arcs to rotate by * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @since 1.6 */ public void quadrantRotate(int numquadrants, double anchorx, double anchory) { switch (numquadrants & 3) { case 0: return; case 1: m02 += anchorx * (m00 - m01) + anchory * (m01 + m00); m12 += anchorx * (m10 - m11) + anchory * (m11 + m10); rotate90(); break; case 2: m02 += anchorx * (m00 + m00) + anchory * (m01 + m01); m12 += anchorx * (m10 + m10) + anchory * (m11 + m11); rotate180(); break; case 3: m02 += anchorx * (m00 + m01) + anchory * (m01 - m00); m12 += anchorx * (m10 + m11) + anchory * (m11 - m10); rotate270(); break; } if (m02 == 0.0 && m12 == 0.0) { state &= ~APPLY_TRANSLATE; } else { state |= APPLY_TRANSLATE; } } /** * Concatenates this transform with a scaling transformation. * This is equivalent to calling concatenate(S), where S is an * <code>AffineTransform</code> represented by the following matrix: * <pre> * [ sx 0 0 ] * [ 0 sy 0 ] * [ 0 0 1 ] * </pre> * @param sx the factor by which coordinates are scaled along the * X axis direction * @param sy the factor by which coordinates are scaled along the * Y axis direction * @since 1.2 */ @Override public void scale(double sx, double sy) { int state = this.state; switch (state) { default: stateError(); /* NOTREACHED */ //$FALL-THROUGH$ case (APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE): case (APPLY_SHEAR | APPLY_SCALE): m00 *= sx; m11 *= sy; //$FALL-THROUGH$ case (APPLY_SHEAR | APPLY_TRANSLATE): case (APPLY_SHEAR): m01 *= sy; m10 *= sx; if (m01 == 0 && m10 == 0) { state &= APPLY_TRANSLATE; if (m00 == 1.0 && m11 == 1.0) { this.type = (state == APPLY_IDENTITY ? TYPE_IDENTITY : TYPE_TRANSLATION); } else { state |= APPLY_SCALE; this.type = TYPE_UNKNOWN; } this.state = state; } return; case (APPLY_SCALE | APPLY_TRANSLATE): case (APPLY_SCALE): m00 *= sx; m11 *= sy; if (m00 == 1.0 && m11 == 1.0) { this.state = (state &= APPLY_TRANSLATE); this.type = (state == APPLY_IDENTITY ? TYPE_IDENTITY : TYPE_TRANSLATION); } else { this.type = TYPE_UNKNOWN; } return; case (APPLY_TRANSLATE): case (APPLY_IDENTITY): m00 = sx; m11 = sy; if (sx != 1.0 || sy != 1.0) { this.state = state | APPLY_SCALE; this.type = TYPE_UNKNOWN; } return; } } /** * Concatenates this transform with a shearing transformation. * This is equivalent to calling concatenate(SH), where SH is an * <code>AffineTransform</code> represented by the following matrix: * <pre> * [ 1 shx 0 ] * [ shy 1 0 ] * [ 0 0 1 ] * </pre> * @param shx the multiplier by which coordinates are shifted in the * direction of the positive X axis as a factor of their Y coordinate * @param shy the multiplier by which coordinates are shifted in the * direction of the positive Y axis as a factor of their X coordinate * @since 1.2 */ @Override public void shear(double shx, double shy) { int state = this.state; switch (state) { default: stateError(); /* NOTREACHED */ //$FALL-THROUGH$ case (APPLY_SHEAR | APPLY_SCALE | APPLY_TRANSLATE): case (APPLY_SHEAR | APPLY_SCALE): double M0, M1; M0 = m00; M1 = m01; m00 = M0 + M1 * shy; m01 = M0 * shx + M1; M0 = m10; M1 = m11; m10 = M0 + M1 * shy; m11 = M0 * shx + M1; updateState(); return; case (APPLY_SHEAR | APPLY_TRANSLATE): case (APPLY_SHEAR): m00 = m01 * shy; m11 = m10 * shx; if (m00 != 0.0 || m11 != 0.0) { this.state = state | APPLY_SCALE; } this.type = TYPE_UNKNOWN; return; case (APPLY_SCALE | APPLY_TRANSLATE): case (APPLY_SCALE): m01 = m00 * shx; m10 = m11 * shy; if (m01 != 0.0 || m10 != 0.0) { this.state = state | APPLY_SHEAR; } this.type = TYPE_UNKNOWN; return; case (APPLY_TRANSLATE): case (APPLY_IDENTITY): m01 = shx; m10 = shy; if (m01 != 0.0 || m10 != 0.0) { this.state = state | APPLY_SCALE | APPLY_SHEAR; this.type = TYPE_UNKNOWN; } return; } } /** * Resets this transform to the Identity transform. * @since 1.2 */ public void setToIdentity() { m00 = m11 = 1.0; m10 = m01 = m02 = m12 = 0.0; state = APPLY_IDENTITY; type = TYPE_IDENTITY; } /** * Sets this transform to a translation transformation. * The matrix representing this transform becomes: * <pre> * [ 1 0 tx ] * [ 0 1 ty ] * [ 0 0 1 ] * </pre> * @param tx the distance by which coordinates are translated in the * X axis direction * @param ty the distance by which coordinates are translated in the * Y axis direction * @since 1.2 */ public void setToTranslation(double tx, double ty) { m00 = 1.0; m10 = 0.0; m01 = 0.0; m11 = 1.0; m02 = tx; m12 = ty; if (tx != 0.0 || ty != 0.0) { state = APPLY_TRANSLATE; type = TYPE_TRANSLATION; } else { state = APPLY_IDENTITY; type = TYPE_IDENTITY; } } /** * Sets this transform to a rotation transformation. * The matrix representing this transform becomes: * <pre> * [ cos(theta) -sin(theta) 0 ] * [ sin(theta) cos(theta) 0 ] * [ 0 0 1 ] * </pre> * Rotating by a positive angle theta rotates points on the positive * X axis toward the positive Y axis. * Note also the discussion of * <a href="#quadrantapproximation">Handling 90-Degree Rotations</a> * above. * @param theta the angle of rotation measured in radians * @since 1.2 */ public void setToRotation(double theta) { double sin = Math.sin(theta); double cos; if (sin == 1.0 || sin == -1.0) { cos = 0.0; state = APPLY_SHEAR; type = TYPE_QUADRANT_ROTATION; } else { cos = Math.cos(theta); if (cos == -1.0) { sin = 0.0; state = APPLY_SCALE; type = TYPE_QUADRANT_ROTATION; } else if (cos == 1.0) { sin = 0.0; state = APPLY_IDENTITY; type = TYPE_IDENTITY; } else { state = APPLY_SHEAR | APPLY_SCALE; type = TYPE_GENERAL_ROTATION; } } m00 = cos; m10 = sin; m01 = -sin; m11 = cos; m02 = 0.0; m12 = 0.0; } /** * Sets this transform to a translated rotation transformation. * This operation is equivalent to translating the coordinates so * that the anchor point is at the origin (S1), then rotating them * about the new origin (S2), and finally translating so that the * intermediate origin is restored to the coordinates of the original * anchor point (S3). * <p> * This operation is equivalent to the following sequence of calls: * <pre> * setToTranslation(anchorx, anchory); // S3: final translation * rotate(theta); // S2: rotate around anchor * translate(-anchorx, -anchory); // S1: translate anchor to origin * </pre> * The matrix representing this transform becomes: * <pre> * [ cos(theta) -sin(theta) x-x*cos+y*sin ] * [ sin(theta) cos(theta) y-x*sin-y*cos ] * [ 0 0 1 ] * </pre> * Rotating by a positive angle theta rotates points on the positive * X axis toward the positive Y axis. * Note also the discussion of * <a href="#quadrantapproximation">Handling 90-Degree Rotations</a> * above. * * @param theta the angle of rotation measured in radians * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @since 1.2 */ public void setToRotation(double theta, double anchorx, double anchory) { setToRotation(theta); double sin = m10; double oneMinusCos = 1.0 - m00; m02 = anchorx * oneMinusCos + anchory * sin; m12 = anchory * oneMinusCos - anchorx * sin; if (m02 != 0.0 || m12 != 0.0) { state |= APPLY_TRANSLATE; type |= TYPE_TRANSLATION; } } /** * Sets this transform to a rotation transformation that rotates * coordinates according to a rotation vector. * All coordinates rotate about the origin by the same amount. * The amount of rotation is such that coordinates along the former * positive X axis will subsequently align with the vector pointing * from the origin to the specified vector coordinates. * If both <code>vecx</code> and <code>vecy</code> are 0.0, * the transform is set to an identity transform. * This operation is equivalent to calling: * <pre> * setToRotation(Math.atan2(vecy, vecx)); * </pre> * * @param vecx the X coordinate of the rotation vector * @param vecy the Y coordinate of the rotation vector * @since 1.6 */ public void setToRotation(double vecx, double vecy) { double sin, cos; if (vecy == 0) { sin = 0.0; if (vecx < 0.0) { cos = -1.0; state = APPLY_SCALE; type = TYPE_QUADRANT_ROTATION; } else { cos = 1.0; state = APPLY_IDENTITY; type = TYPE_IDENTITY; } } else if (vecx == 0) { cos = 0.0; sin = (vecy > 0.0) ? 1.0 : -1.0; state = APPLY_SHEAR; type = TYPE_QUADRANT_ROTATION; } else { double len = Math.sqrt(vecx * vecx + vecy * vecy); cos = vecx / len; sin = vecy / len; state = APPLY_SHEAR | APPLY_SCALE; type = TYPE_GENERAL_ROTATION; } m00 = cos; m10 = sin; m01 = -sin; m11 = cos; m02 = 0.0; m12 = 0.0; } /** * Sets this transform to a rotation transformation that rotates * coordinates around an anchor point according to a rotation * vector. * All coordinates rotate about the specified anchor coordinates * by the same amount. * The amount of rotation is such that coordinates along the former * positive X axis will subsequently align with the vector pointing * from the origin to the specified vector coordinates. * If both <code>vecx</code> and <code>vecy</code> are 0.0, * the transform is set to an identity transform. * This operation is equivalent to calling: * <pre> * setToTranslation(Math.atan2(vecy, vecx), anchorx, anchory); * </pre> * * @param vecx the X coordinate of the rotation vector * @param vecy the Y coordinate of the rotation vector * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @since 1.6 */ public void setToRotation(double vecx, double vecy, double anchorx, double anchory) { setToRotation(vecx, vecy); double sin = m10; double oneMinusCos = 1.0 - m00; m02 = anchorx * oneMinusCos + anchory * sin; m12 = anchory * oneMinusCos - anchorx * sin; if (m02 != 0.0 || m12 != 0.0) { state |= APPLY_TRANSLATE; type |= TYPE_TRANSLATION; } } /** * Sets this transform to a rotation transformation that rotates * coordinates by the specified number of quadrants. * This operation is equivalent to calling: * <pre> * setToRotation(numquadrants * Math.PI / 2.0); * </pre> * Rotating by a positive number of quadrants rotates points on * the positive X axis toward the positive Y axis. * @param numquadrants the number of 90 degree arcs to rotate by * @since 1.6 */ public void setToQuadrantRotation(int numquadrants) { switch (numquadrants & 3) { case 0: m00 = 1.0; m10 = 0.0; m01 = 0.0; m11 = 1.0; m02 = 0.0; m12 = 0.0; state = APPLY_IDENTITY; type = TYPE_IDENTITY; break; case 1: m00 = 0.0; m10 = 1.0; m01 = -1.0; m11 = 0.0; m02 = 0.0; m12 = 0.0; state = APPLY_SHEAR; type = TYPE_QUADRANT_ROTATION; break; case 2: m00 = -1.0; m10 = 0.0; m01 = 0.0; m11 = -1.0; m02 = 0.0; m12 = 0.0; state = APPLY_SCALE; type = TYPE_QUADRANT_ROTATION; break; case 3: m00 = 0.0; m10 = -1.0; m01 = 1.0; m11 = 0.0; m02 = 0.0; m12 = 0.0; state = APPLY_SHEAR; type = TYPE_QUADRANT_ROTATION; break; } } /** * Sets this transform to a translated rotation transformation * that rotates coordinates by the specified number of quadrants * around the specified anchor point. * This operation is equivalent to calling: * <pre> * setToRotation(numquadrants * Math.PI / 2.0, anchorx, anchory); * </pre> * Rotating by a positive number of quadrants rotates points on * the positive X axis toward the positive Y axis. * * @param numquadrants the number of 90 degree arcs to rotate by * @param anchorx the X coordinate of the rotation anchor point * @param anchory the Y coordinate of the rotation anchor point * @since 1.6 */ public void setToQuadrantRotation(int numquadrants, double anchorx, double anchory) { switch (numquadrants & 3) { case 0: m00 = 1.0; m10 = 0.0; m01 = 0.0; m11 = 1.0; m02 = 0.0; m12 = 0.0; state = APPLY_IDENTITY; type = TYPE_IDENTITY; break; case 1: m00 = 0.0; m10 = 1.0; m01 = -1.0; m11 = 0.0; m02 = anchorx + anchory; m12 = anchory - anchorx; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SHEAR; type = TYPE_QUADRANT_ROTATION; } else { state = APPLY_SHEAR | APPLY_TRANSLATE; type = TYPE_QUADRANT_ROTATION | TYPE_TRANSLATION; } break; case 2: m00 = -1.0; m10 = 0.0; m01 = 0.0; m11 = -1.0; m02 = anchorx + anchorx; m12 = anchory + anchory; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SCALE; type = TYPE_QUADRANT_ROTATION; } else { state = APPLY_SCALE | APPLY_TRANSLATE; type = TYPE_QUADRANT_ROTATION | TYPE_TRANSLATION; } break; case 3: m00 = 0.0; m10 = -1.0; m01 = 1.0; m11 = 0.0; m02 = anchorx - anchory; m12 = anchory + anchorx; if (m02 == 0.0 && m12 == 0.0) { state = APPLY_SHEAR; type = TYPE_QUADRANT_ROTATION; } else { state = APPLY_SHEAR | APPLY_TRANSLATE; type = TYPE_QUADRANT_ROTATION | TYPE_TRANSLATION; } break; } } /** * Sets this transform to a scaling transformation. * The matrix representing this transform becomes: * <pre> * [ sx 0 0 ] * [ 0 sy 0 ] * [ 0 0 1 ] * </pre> * @param sx the factor by which coordinates are scaled along the * X axis direction * @param sy the factor by which coordinates are scaled along the * Y axis direction * @since 1.2 */ public void setToScale(double sx, double sy) { m00 = sx; m10 = 0.0; m01 = 0.0; m11 = sy; m02 = 0.0; m12 = 0.0; if (sx != 1.0 || sy != 1.0) { state = APPLY_SCALE; type = TYPE_UNKNOWN; } else { state = APPLY_IDENTITY; type = TYPE_IDENTITY; } } /** * Sets this transform to a shearing transformation. * The matrix representing this transform becomes: * <pre> * [ 1 shx 0 ] * [ shy 1 0 ] * [ 0 0 1 ] * </pre> * @param shx the multiplier by which coordinates are shifted in the * direction of the positive X axis as a factor of their Y coordinate * @param shy the multiplier by which coordinates are shifted in the * direction of the positive Y axis as a factor of their X coordinate * @since 1.2 */ public void setToShear(double shx, double shy) { m00 = 1.0; m01 = shx; m10 = shy; m11 = 1.0; m02 = 0.0; m12 = 0.0; if (shx != 0.0 || shy != 0.0) { state = (APPLY_SHEAR | APPLY_SCALE); type = TYPE_UNKNOWN; } else { state = APPLY_IDENTITY; type = TYPE_IDENTITY; } } /** * Sets this transform to the matrix specified by the 6 * double precision values. * * @param m00 the X coordinate scaling element of the 3x3 matrix * @param m10 the Y coordinate shearing element of the 3x3 matrix * @param m01 the X coordinate shearing element of the 3x3 matrix * @param m11 the Y coordinate scaling element of the 3x3 matrix * @param m02 the X coordinate translation element of the 3x3 matrix * @param m12 the Y coordinate translation element of the 3x3 matrix * @since 1.2 */ 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; updateState(); } // Round values to sane precision for printing // Note that Math.sin(Math.PI) has an error of about 10^-16 private static double _matround(double matval) { return Math.rint(matval * 1E15) / 1E15; } /** * Returns a <code>String</code> that represents the value of this * {@link Object}. * @return a <code>String</code> representing the value of this * <code>Object</code>. * @since 1.2 */ @Override public String toString() { return ("AffineTransform[[" + _matround(m00) + ", " + _matround(m01) + ", " + _matround(m02) + "], [" + _matround(m10) + ", " + _matround(m11) + ", " + _matround(m12) + "]]"); } /** * Returns <code>true</code> if this <code>AffineTransform</code> is * an identity transform. * @return <code>true</code> if this <code>AffineTransform</code> is * an identity transform; <code>false</code> otherwise. * @since 1.2 */ public boolean isIdentity() { return (state == APPLY_IDENTITY || (getType() == TYPE_IDENTITY)); } /** * Returns a copy of this <code>AffineTransform</code> object. * @return an <code>Object</code> that is a copy of this * <code>AffineTransform</code> object. * @since 1.2 */ @SuppressWarnings("all") public Object duplicate(){ return new AffineTransform(this); } @Override public Transform createClone() { return (AffineTransform) duplicate(); } }