- All Implemented Interfaces:
Serializable
,Cloneable
AffineTransform
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.
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 (x,y)
into
destination coordinates (x',y')
by considering
them to be a column vector and multiplying the coordinate vector
by the matrix according to the following process:
[ x'] [ m00 m01 m02 ] [ x ] [ m00x + m01y + m02 ] [ y'] = [ m10 m11 m12 ] [ y ] = [ m10x + m11y + m12 ] [ 1 ] [ 0 0 1 ] [ 1 ] [ 1 ]
Handling 90-Degree Rotations
In some variations of the rotate
methods in the
AffineTransform
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.
Since 90 degrees is represented as PI/2
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 PI/2
but never close enough
for the sine or cosine to be exactly 0.0, 1.0 or -1.0.
The implementations of Math.sin()
and
Math.cos()
correspondingly never return 0.0
for any case other than Math.sin(0.0)
.
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.
The net result of these issues is that if the
Math.sin()
and Math.cos()
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 rotate(Math.PI/2.0)
,
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.
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 theta as a quadrant
rotation if either Math.sin(theta)
or
Math.cos(theta)
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 Math.PI/2.0
.
- Since:
- 1.2
- See Also:
-
Field Summary
Modifier and TypeFieldDescriptionstatic final int
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.static final int
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.static final int
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.static final int
This constant indicates that the transform defined by this object performs an arbitrary conversion of the input coordinates.static final int
This constant indicates that the transform defined by this object is an identity transform.static final int
This constant is a bit mask for any of the rotation flag bits.static final int
This constant is a bit mask for any of the scale flag bits.static final int
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.static final int
This flag bit indicates that the transform defined by this object performs a translation in addition to the conversions indicated by other flag bits.static final int
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. -
Constructor Summary
ConstructorDescriptionConstructs a newAffineTransform
representing the Identity transformation.AffineTransform
(double[] flatmatrix) Constructs a newAffineTransform
from an array of double precision values representing either the 4 non-translation entries or the 6 specifiable entries of the 3x3 transformation matrix.AffineTransform
(double m00, double m10, double m01, double m11, double m02, double m12) Constructs a newAffineTransform
from 6 double precision values representing the 6 specifiable entries of the 3x3 transformation matrix.AffineTransform
(float[] flatmatrix) Constructs a newAffineTransform
from an array of floating point values representing either the 4 non-translation entries or the 6 specifiable entries of the 3x3 transformation matrix.AffineTransform
(float m00, float m10, float m01, float m11, float m02, float m12) Constructs a newAffineTransform
from 6 floating point values representing the 6 specifiable entries of the 3x3 transformation matrix.Constructs a newAffineTransform
that is a copy of the specifiedAffineTransform
object. -
Method Summary
Modifier and TypeMethodDescriptionclone()
Returns a copy of thisAffineTransform
object.void
Concatenates anAffineTransform Tx
to thisAffineTransform
Cx in the most commonly useful way to provide a new user space that is mapped to the former user space byTx
.Returns anAffineTransform
object representing the inverse transformation.createTransformedShape
(Shape pSrc) Returns a newShape
object defined by the geometry of the specifiedShape
after it has been transformed by this transform.void
deltaTransform
(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms an array of relative distance vectors by this transform.deltaTransform
(Point2D ptSrc, Point2D ptDst) Transforms the relative distance vector specified byptSrc
and stores the result inptDst
.boolean
Returnstrue
if thisAffineTransform
represents the same affine coordinate transform as the specified argument.double
Returns the determinant of the matrix representation of the transform.void
getMatrix
(double[] flatmatrix) Retrieves the 6 specifiable values in the 3x3 affine transformation matrix and places them into an array of double precisions values.static AffineTransform
getQuadrantRotateInstance
(int numquadrants) Returns a transform that rotates coordinates by the specified number of quadrants.static AffineTransform
getQuadrantRotateInstance
(int numquadrants, double anchorx, double anchory) Returns a transform that rotates coordinates by the specified number of quadrants around the specified anchor point.static AffineTransform
getRotateInstance
(double theta) Returns a transform representing a rotation transformation.static AffineTransform
getRotateInstance
(double vecx, double vecy) Returns a transform that rotates coordinates according to a rotation vector.static AffineTransform
getRotateInstance
(double theta, double anchorx, double anchory) Returns a transform that rotates coordinates around an anchor point.static AffineTransform
getRotateInstance
(double vecx, double vecy, double anchorx, double anchory) Returns a transform that rotates coordinates around an anchor point according to a rotation vector.static AffineTransform
getScaleInstance
(double sx, double sy) Returns a transform representing a scaling transformation.double
Returns them00
element of the 3x3 affine transformation matrix.double
Returns them11
element of the 3x3 affine transformation matrix.static AffineTransform
getShearInstance
(double shx, double shy) Returns a transform representing a shearing transformation.double
Returns the X coordinate shearing element (m01) of the 3x3 affine transformation matrix.double
Returns the Y coordinate shearing element (m10) of the 3x3 affine transformation matrix.static AffineTransform
getTranslateInstance
(double tx, double ty) Returns a transform representing a translation transformation.double
Returns the X coordinate of the translation element (m02) of the 3x3 affine transformation matrix.double
Returns the Y coordinate of the translation element (m12) of the 3x3 affine transformation matrix.int
getType()
Retrieves the flag bits describing the conversion properties of this transform.int
hashCode()
Returns the hashcode for this transform.void
inverseTransform
(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Inverse transforms an array of double precision coordinates by this transform.inverseTransform
(Point2D ptSrc, Point2D ptDst) Inverse transforms the specifiedptSrc
and stores the result inptDst
.void
invert()
Sets this transform to the inverse of itself.boolean
Returnstrue
if thisAffineTransform
is an identity transform.void
Concatenates anAffineTransform Tx
to thisAffineTransform
Cx in a less commonly used way such thatTx
modifies the coordinate transformation relative to the absolute pixel space rather than relative to the existing user space.void
quadrantRotate
(int numquadrants) Concatenates this transform with a transform that rotates coordinates by the specified number of quadrants.void
quadrantRotate
(int numquadrants, double anchorx, double anchory) Concatenates this transform with a transform that rotates coordinates by the specified number of quadrants around the specified anchor point.void
rotate
(double theta) Concatenates this transform with a rotation transformation.void
rotate
(double vecx, double vecy) Concatenates this transform with a transform that rotates coordinates according to a rotation vector.void
rotate
(double theta, double anchorx, double anchory) Concatenates this transform with a transform that rotates coordinates around an anchor point.void
rotate
(double vecx, double vecy, double anchorx, double anchory) Concatenates this transform with a transform that rotates coordinates around an anchor point according to a rotation vector.void
scale
(double sx, double sy) Concatenates this transform with a scaling transformation.void
Resets this transform to the Identity transform.void
setToQuadrantRotation
(int numquadrants) Sets this transform to a rotation transformation that rotates coordinates by the specified number of quadrants.void
setToQuadrantRotation
(int numquadrants, double anchorx, double anchory) Sets this transform to a translated rotation transformation that rotates coordinates by the specified number of quadrants around the specified anchor point.void
setToRotation
(double theta) Sets this transform to a rotation transformation.void
setToRotation
(double vecx, double vecy) Sets this transform to a rotation transformation that rotates coordinates according to a rotation vector.void
setToRotation
(double theta, double anchorx, double anchory) Sets this transform to a translated rotation transformation.void
setToRotation
(double vecx, double vecy, double anchorx, double anchory) Sets this transform to a rotation transformation that rotates coordinates around an anchor point according to a rotation vector.void
setToScale
(double sx, double sy) Sets this transform to a scaling transformation.void
setToShear
(double shx, double shy) Sets this transform to a shearing transformation.void
setToTranslation
(double tx, double ty) Sets this transform to a translation transformation.void
setTransform
(double m00, double m10, double m01, double m11, double m02, double m12) Sets this transform to the matrix specified by the 6 double precision values.void
Sets this transform to a copy of the transform in the specifiedAffineTransform
object.void
shear
(double shx, double shy) Concatenates this transform with a shearing transformation.toString()
Returns aString
that represents the value of thisObject
.void
transform
(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms an array of double precision coordinates by this transform.void
transform
(double[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms an array of double precision coordinates by this transform and stores the results into an array of floats.void
transform
(float[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms an array of floating point coordinates by this transform and stores the results into an array of doubles.void
transform
(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms an array of floating point coordinates by this transform.void
Transforms an array of point objects by this transform.Transforms the specifiedptSrc
and stores the result inptDst
.void
translate
(double tx, double ty) Concatenates this transform with a translation transformation.
-
Field Details
-
TYPE_IDENTITY
public static final int TYPE_IDENTITYThis 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.- Since:
- 1.2
- See Also:
-
TYPE_TRANSLATION
public static final int TYPE_TRANSLATIONThis 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.- Since:
- 1.2
- See Also:
-
TYPE_UNIFORM_SCALE
public static final int TYPE_UNIFORM_SCALEThis 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.- Since:
- 1.2
- See Also:
-
TYPE_GENERAL_SCALE
public static final int TYPE_GENERAL_SCALEThis 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.- Since:
- 1.2
- See Also:
-
TYPE_MASK_SCALE
public static final int TYPE_MASK_SCALEThis constant is a bit mask for any of the scale flag bits.- Since:
- 1.2
- See Also:
-
TYPE_FLIP
public static final int TYPE_FLIPThis 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.- Since:
- 1.2
- See Also:
-
TYPE_QUADRANT_ROTATION
public static final int TYPE_QUADRANT_ROTATIONThis 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.- Since:
- 1.2
- See Also:
-
TYPE_GENERAL_ROTATION
public static final int TYPE_GENERAL_ROTATIONThis 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.- Since:
- 1.2
- See Also:
-
TYPE_MASK_ROTATION
public static final int TYPE_MASK_ROTATIONThis constant is a bit mask for any of the rotation flag bits.- Since:
- 1.2
- See Also:
-
TYPE_GENERAL_TRANSFORM
public static final int TYPE_GENERAL_TRANSFORMThis 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.- Since:
- 1.2
- See Also:
-
-
Constructor Details
-
AffineTransform
public AffineTransform()Constructs a newAffineTransform
representing the Identity transformation.- Since:
- 1.2
-
AffineTransform
Constructs a newAffineTransform
that is a copy of the specifiedAffineTransform
object.- Parameters:
Tx
- theAffineTransform
object to copy- Since:
- 1.2
-
AffineTransform
@ConstructorProperties({"scaleX","shearY","shearX","scaleY","translateX","translateY"}) public AffineTransform(float m00, float m10, float m01, float m11, float m02, float m12) Constructs a newAffineTransform
from 6 floating point values representing the 6 specifiable entries of the 3x3 transformation matrix.- Parameters:
m00
- the X coordinate scaling element of the 3x3 matrixm10
- the Y coordinate shearing element of the 3x3 matrixm01
- the X coordinate shearing element of the 3x3 matrixm11
- the Y coordinate scaling element of the 3x3 matrixm02
- the X coordinate translation element of the 3x3 matrixm12
- the Y coordinate translation element of the 3x3 matrix- Since:
- 1.2
-
AffineTransform
public AffineTransform(float[] flatmatrix) Constructs a newAffineTransform
from an array of floating point 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]}.- Parameters:
flatmatrix
- the float array containing the values to be set in the newAffineTransform
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
-
AffineTransform
public AffineTransform(double m00, double m10, double m01, double m11, double m02, double m12) Constructs a newAffineTransform
from 6 double precision values representing the 6 specifiable entries of the 3x3 transformation matrix.- Parameters:
m00
- the X coordinate scaling element of the 3x3 matrixm10
- the Y coordinate shearing element of the 3x3 matrixm01
- the X coordinate shearing element of the 3x3 matrixm11
- the Y coordinate scaling element of the 3x3 matrixm02
- the X coordinate translation element of the 3x3 matrixm12
- the Y coordinate translation element of the 3x3 matrix- Since:
- 1.2
-
AffineTransform
public AffineTransform(double[] flatmatrix) Constructs a newAffineTransform
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]}.- Parameters:
flatmatrix
- the double array containing the values to be set in the newAffineTransform
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
-
-
Method Details
-
getTranslateInstance
Returns a transform representing a translation transformation. The matrix representing the returned transform is:[ 1 0 tx ] [ 0 1 ty ] [ 0 0 1 ]
- Parameters:
tx
- the distance by which coordinates are translated in the X axis directionty
- the distance by which coordinates are translated in the Y axis direction- Returns:
- an
AffineTransform
object that represents a translation transformation, created with the specified vector. - Since:
- 1.2
-
getRotateInstance
Returns a transform representing a rotation transformation. The matrix representing the returned transform is:[ cos(theta) -sin(theta) 0 ] [ sin(theta) cos(theta) 0 ] [ 0 0 1 ]
Rotating by a positive angle theta rotates points on the positive X axis toward the positive Y axis. Note also the discussion of Handling 90-Degree Rotations above.- Parameters:
theta
- the angle of rotation measured in radians- Returns:
- an
AffineTransform
object that is a rotation transformation, created with the specified angle of rotation. - Since:
- 1.2
-
getRotateInstance
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).This operation is equivalent to the following sequence of calls:
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
The matrix representing the returned transform is:[ cos(theta) -sin(theta) x-x*cos+y*sin ] [ sin(theta) cos(theta) y-x*sin-y*cos ] [ 0 0 1 ]
Rotating by a positive angle theta rotates points on the positive X axis toward the positive Y axis. Note also the discussion of Handling 90-Degree Rotations above.- Parameters:
theta
- the angle of rotation measured in radiansanchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Returns:
- an
AffineTransform
object that rotates coordinates around the specified point by the specified angle of rotation. - Since:
- 1.2
-
getRotateInstance
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 bothvecx
andvecy
are 0.0, an identity transform is returned. This operation is equivalent to calling:AffineTransform.getRotateInstance(Math.atan2(vecy, vecx));
- Parameters:
vecx
- the X coordinate of the rotation vectorvecy
- the Y coordinate of the rotation vector- Returns:
- an
AffineTransform
object that rotates coordinates according to the specified rotation vector. - Since:
- 1.6
-
getRotateInstance
public static AffineTransform getRotateInstance(double vecx, double vecy, double anchorx, double anchory) Returns 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 bothvecx
andvecy
are 0.0, an identity transform is returned. This operation is equivalent to calling:AffineTransform.getRotateInstance(Math.atan2(vecy, vecx), anchorx, anchory);
- Parameters:
vecx
- the X coordinate of the rotation vectorvecy
- the Y coordinate of the rotation vectoranchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Returns:
- an
AffineTransform
object that rotates coordinates around the specified point according to the specified rotation vector. - Since:
- 1.6
-
getQuadrantRotateInstance
Returns a transform that rotates coordinates by the specified number of quadrants. This operation is equivalent to calling:AffineTransform.getRotateInstance(numquadrants * Math.PI / 2.0);
Rotating by a positive number of quadrants rotates points on the positive X axis toward the positive Y axis.- Parameters:
numquadrants
- the number of 90 degree arcs to rotate by- Returns:
- an
AffineTransform
object that rotates coordinates by the specified number of quadrants. - Since:
- 1.6
-
getQuadrantRotateInstance
public static AffineTransform getQuadrantRotateInstance(int numquadrants, double anchorx, double anchory) Returns a transform that rotates coordinates by the specified number of quadrants around the specified anchor point. This operation is equivalent to calling:AffineTransform.getRotateInstance(numquadrants * Math.PI / 2.0, anchorx, anchory);
Rotating by a positive number of quadrants rotates points on the positive X axis toward the positive Y axis.- Parameters:
numquadrants
- the number of 90 degree arcs to rotate byanchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Returns:
- an
AffineTransform
object that rotates coordinates by the specified number of quadrants around the specified anchor point. - Since:
- 1.6
-
getScaleInstance
Returns a transform representing a scaling transformation. The matrix representing the returned transform is:[ sx 0 0 ] [ 0 sy 0 ] [ 0 0 1 ]
- Parameters:
sx
- the factor by which coordinates are scaled along the X axis directionsy
- the factor by which coordinates are scaled along the Y axis direction- Returns:
- an
AffineTransform
object that scales coordinates by the specified factors. - Since:
- 1.2
-
getShearInstance
Returns a transform representing a shearing transformation. The matrix representing the returned transform is:[ 1 shx 0 ] [ shy 1 0 ] [ 0 0 1 ]
- Parameters:
shx
- the multiplier by which coordinates are shifted in the direction of the positive X axis as a factor of their Y coordinateshy
- the multiplier by which coordinates are shifted in the direction of the positive Y axis as a factor of their X coordinate- Returns:
- an
AffineTransform
object that shears coordinates by the specified multipliers. - Since:
- 1.2
-
getType
public int getType()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 appropriate 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.- Returns:
- the OR combination of any of the indicated flags that apply to this transform
- Since:
- 1.2
- See Also:
-
getDeterminant
public double getDeterminant()Returns the determinant of the matrix representation of the transform. The determinant is useful both to determine if the transform can be inverted and to get a single value representing the combined X and Y scaling of the transform.If the determinant is non-zero, then this transform is invertible and the various methods that depend on the inverse transform do not need to throw a
NoninvertibleTransformException
. If the determinant is zero then this transform can not be inverted since the transform maps all input coordinates onto a line or a point. If the determinant is near enough to zero then inverse transform operations might not carry enough precision to produce meaningful results.If this transform represents a uniform scale, as indicated by the
getType
method then the determinant also represents the square of the uniform scale factor by which all of the points are expanded from or contracted towards the origin. If this transform represents a non-uniform scale or more general transform then the determinant is not likely to represent a value useful for any purpose other than determining if inverse transforms are possible.Mathematically, the determinant is calculated using the formula:
| m00 m01 m02 | | m10 m11 m12 | = m00 * m11 - m01 * m10 | 0 0 1 |
- Returns:
- the determinant of the matrix used to transform the coordinates.
- Since:
- 1.2
- See Also:
-
getMatrix
public void getMatrix(double[] flatmatrix) 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 }- Parameters:
flatmatrix
- the double array used to store the returned values.- Since:
- 1.2
- See Also:
-
getScaleX
public double getScaleX()Returns them00
element of the 3x3 affine transformation matrix. This matrix factor determines how input X coordinates will affect output X coordinates and is one element of the scale of the transform. To measure the full amount by which X coordinates are stretched or contracted by this transform, use the following code:Point2D p = new Point2D.Double(1, 0); p = tx.deltaTransform(p, p); double scaleX = p.distance(0, 0);
- Returns:
- a double value that is
m00
element of the 3x3 affine transformation matrix. - Since:
- 1.2
- See Also:
-
getScaleY
public double getScaleY()Returns them11
element of the 3x3 affine transformation matrix. This matrix factor determines how input Y coordinates will affect output Y coordinates and is one element of the scale of the transform. To measure the full amount by which Y coordinates are stretched or contracted by this transform, use the following code:Point2D p = new Point2D.Double(0, 1); p = tx.deltaTransform(p, p); double scaleY = p.distance(0, 0);
- Returns:
- a double value that is
m11
element of the 3x3 affine transformation matrix. - Since:
- 1.2
- See Also:
-
getShearX
public double getShearX()Returns the X coordinate shearing element (m01) of the 3x3 affine transformation matrix.- Returns:
- a double value that is the X coordinate of the shearing element of the affine transformation matrix.
- Since:
- 1.2
- See Also:
-
getShearY
public double getShearY()Returns the Y coordinate shearing element (m10) of the 3x3 affine transformation matrix.- Returns:
- a double value that is the Y coordinate of the shearing element of the affine transformation matrix.
- Since:
- 1.2
- See Also:
-
getTranslateX
public double getTranslateX()Returns the X coordinate of the translation element (m02) of the 3x3 affine transformation matrix.- Returns:
- a double value that is the X coordinate of the translation element of the affine transformation matrix.
- Since:
- 1.2
- See Also:
-
getTranslateY
public double getTranslateY()Returns the Y coordinate of the translation element (m12) of the 3x3 affine transformation matrix.- Returns:
- a double value that is the Y coordinate of the translation element of the affine transformation matrix.
- Since:
- 1.2
- See Also:
-
translate
public void translate(double tx, double ty) Concatenates this transform with a translation transformation. This is equivalent to calling concatenate(T), where T is anAffineTransform
represented by the following matrix:[ 1 0 tx ] [ 0 1 ty ] [ 0 0 1 ]
- Parameters:
tx
- the distance by which coordinates are translated in the X axis directionty
- the distance by which coordinates are translated in the Y axis direction- Since:
- 1.2
-
rotate
public void rotate(double theta) Concatenates this transform with a rotation transformation. This is equivalent to calling concatenate(R), where R is anAffineTransform
represented by the following matrix:[ cos(theta) -sin(theta) 0 ] [ sin(theta) cos(theta) 0 ] [ 0 0 1 ]
Rotating by a positive angle theta rotates points on the positive X axis toward the positive Y axis. Note also the discussion of Handling 90-Degree Rotations above.- Parameters:
theta
- the angle of rotation measured in radians- Since:
- 1.2
-
rotate
public void rotate(double theta, double anchorx, double anchory) 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).This operation is equivalent to the following sequence of calls:
translate(anchorx, anchory); // S3: final translation rotate(theta); // S2: rotate around anchor translate(-anchorx, -anchory); // S1: translate anchor to origin
Rotating by a positive angle theta rotates points on the positive X axis toward the positive Y axis. Note also the discussion of Handling 90-Degree Rotations above.- Parameters:
theta
- the angle of rotation measured in radiansanchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Since:
- 1.2
-
rotate
public void rotate(double vecx, double vecy) 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 bothvecx
andvecy
are 0.0, no additional rotation is added to this transform. This operation is equivalent to calling:rotate(Math.atan2(vecy, vecx));
- Parameters:
vecx
- the X coordinate of the rotation vectorvecy
- the Y coordinate of the rotation vector- Since:
- 1.6
-
rotate
public void rotate(double vecx, double vecy, double anchorx, double anchory) 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 bothvecx
andvecy
are 0.0, the transform is not modified in any way. This method is equivalent to calling:rotate(Math.atan2(vecy, vecx), anchorx, anchory);
- Parameters:
vecx
- the X coordinate of the rotation vectorvecy
- the Y coordinate of the rotation vectoranchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Since:
- 1.6
-
quadrantRotate
public void quadrantRotate(int numquadrants) Concatenates this transform with a transform that rotates coordinates by the specified number of quadrants. This is equivalent to calling:rotate(numquadrants * Math.PI / 2.0);
Rotating by a positive number of quadrants rotates points on the positive X axis toward the positive Y axis.- Parameters:
numquadrants
- the number of 90 degree arcs to rotate by- Since:
- 1.6
-
quadrantRotate
public void quadrantRotate(int numquadrants, double anchorx, double anchory) 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:rotate(numquadrants * Math.PI / 2.0, anchorx, anchory);
Rotating by a positive number of quadrants rotates points on the positive X axis toward the positive Y axis.- Parameters:
numquadrants
- the number of 90 degree arcs to rotate byanchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Since:
- 1.6
-
scale
public void scale(double sx, double sy) Concatenates this transform with a scaling transformation. This is equivalent to calling concatenate(S), where S is anAffineTransform
represented by the following matrix:[ sx 0 0 ] [ 0 sy 0 ] [ 0 0 1 ]
- Parameters:
sx
- the factor by which coordinates are scaled along the X axis directionsy
- the factor by which coordinates are scaled along the Y axis direction- Since:
- 1.2
-
shear
public void shear(double shx, double shy) Concatenates this transform with a shearing transformation. This is equivalent to calling concatenate(SH), where SH is anAffineTransform
represented by the following matrix:[ 1 shx 0 ] [ shy 1 0 ] [ 0 0 1 ]
- Parameters:
shx
- the multiplier by which coordinates are shifted in the direction of the positive X axis as a factor of their Y coordinateshy
- 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
-
setToIdentity
public void setToIdentity()Resets this transform to the Identity transform.- Since:
- 1.2
-
setToTranslation
public void setToTranslation(double tx, double ty) Sets this transform to a translation transformation. The matrix representing this transform becomes:[ 1 0 tx ] [ 0 1 ty ] [ 0 0 1 ]
- Parameters:
tx
- the distance by which coordinates are translated in the X axis directionty
- the distance by which coordinates are translated in the Y axis direction- Since:
- 1.2
-
setToRotation
public void setToRotation(double theta) Sets this transform to a rotation transformation. The matrix representing this transform becomes:[ cos(theta) -sin(theta) 0 ] [ sin(theta) cos(theta) 0 ] [ 0 0 1 ]
Rotating by a positive angle theta rotates points on the positive X axis toward the positive Y axis. Note also the discussion of Handling 90-Degree Rotations above.- Parameters:
theta
- the angle of rotation measured in radians- Since:
- 1.2
-
setToRotation
public void setToRotation(double theta, double anchorx, double anchory) 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).This operation is equivalent to the following sequence of calls:
setToTranslation(anchorx, anchory); // S3: final translation rotate(theta); // S2: rotate around anchor translate(-anchorx, -anchory); // S1: translate anchor to origin
The matrix representing this transform becomes:[ cos(theta) -sin(theta) x-x*cos+y*sin ] [ sin(theta) cos(theta) y-x*sin-y*cos ] [ 0 0 1 ]
Rotating by a positive angle theta rotates points on the positive X axis toward the positive Y axis. Note also the discussion of Handling 90-Degree Rotations above.- Parameters:
theta
- the angle of rotation measured in radiansanchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Since:
- 1.2
-
setToRotation
public void setToRotation(double vecx, double vecy) 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 bothvecx
andvecy
are 0.0, the transform is set to an identity transform. This operation is equivalent to calling:setToRotation(Math.atan2(vecy, vecx));
- Parameters:
vecx
- the X coordinate of the rotation vectorvecy
- the Y coordinate of the rotation vector- Since:
- 1.6
-
setToRotation
public void setToRotation(double vecx, double vecy, double anchorx, double anchory) 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 bothvecx
andvecy
are 0.0, the transform is set to an identity transform. This operation is equivalent to calling:setToTranslation(Math.atan2(vecy, vecx), anchorx, anchory);
- Parameters:
vecx
- the X coordinate of the rotation vectorvecy
- the Y coordinate of the rotation vectoranchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Since:
- 1.6
-
setToQuadrantRotation
public void setToQuadrantRotation(int numquadrants) Sets this transform to a rotation transformation that rotates coordinates by the specified number of quadrants. This operation is equivalent to calling:setToRotation(numquadrants * Math.PI / 2.0);
Rotating by a positive number of quadrants rotates points on the positive X axis toward the positive Y axis.- Parameters:
numquadrants
- the number of 90 degree arcs to rotate by- Since:
- 1.6
-
setToQuadrantRotation
public void setToQuadrantRotation(int numquadrants, double anchorx, double anchory) 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:setToRotation(numquadrants * Math.PI / 2.0, anchorx, anchory);
Rotating by a positive number of quadrants rotates points on the positive X axis toward the positive Y axis.- Parameters:
numquadrants
- the number of 90 degree arcs to rotate byanchorx
- the X coordinate of the rotation anchor pointanchory
- the Y coordinate of the rotation anchor point- Since:
- 1.6
-
setToScale
public void setToScale(double sx, double sy) Sets this transform to a scaling transformation. The matrix representing this transform becomes:[ sx 0 0 ] [ 0 sy 0 ] [ 0 0 1 ]
- Parameters:
sx
- the factor by which coordinates are scaled along the X axis directionsy
- the factor by which coordinates are scaled along the Y axis direction- Since:
- 1.2
-
setToShear
public void setToShear(double shx, double shy) Sets this transform to a shearing transformation. The matrix representing this transform becomes:[ 1 shx 0 ] [ shy 1 0 ] [ 0 0 1 ]
- Parameters:
shx
- the multiplier by which coordinates are shifted in the direction of the positive X axis as a factor of their Y coordinateshy
- 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
-
setTransform
Sets this transform to a copy of the transform in the specifiedAffineTransform
object.- Parameters:
Tx
- theAffineTransform
object from which to copy the transform- Since:
- 1.2
-
setTransform
public void setTransform(double m00, double m10, double m01, double m11, double m02, double m12) Sets this transform to the matrix specified by the 6 double precision values.- Parameters:
m00
- the X coordinate scaling element of the 3x3 matrixm10
- the Y coordinate shearing element of the 3x3 matrixm01
- the X coordinate shearing element of the 3x3 matrixm11
- the Y coordinate scaling element of the 3x3 matrixm02
- the X coordinate translation element of the 3x3 matrixm12
- the Y coordinate translation element of the 3x3 matrix- Since:
- 1.2
-
concatenate
Concatenates anAffineTransform Tx
to thisAffineTransform
Cx in the most commonly useful way to provide a new user space that is mapped to the former user space byTx
. Cx is updated to perform the combined transformation. Transforming a point p by the updated transform Cx' is equivalent to first transforming p byTx
and then transforming the result by the original transform Cx like this: Cx'(p) = Cx(Tx(p)) In matrix notation, if this transform Cx is represented by the matrix [this] andTx
is represented by the matrix [Tx] then this method does the following:[this] = [this] x [Tx]
- Parameters:
Tx
- theAffineTransform
object to be concatenated with thisAffineTransform
object.- Since:
- 1.2
- See Also:
-
preConcatenate
Concatenates anAffineTransform Tx
to thisAffineTransform
Cx in a less commonly used way such thatTx
modifies the coordinate transformation relative to the absolute pixel space rather than relative to the existing user space. Cx is updated to perform the combined transformation. Transforming a point p by the updated transform Cx' is equivalent to first transforming p by the original transform Cx and then transforming the result byTx
like this: Cx'(p) = Tx(Cx(p)) In matrix notation, if this transform Cx is represented by the matrix [this] andTx
is represented by the matrix [Tx] then this method does the following:[this] = [Tx] x [this]
- Parameters:
Tx
- theAffineTransform
object to be concatenated with thisAffineTransform
object.- Since:
- 1.2
- See Also:
-
createInverse
Returns anAffineTransform
object representing the inverse transformation. The inverse transform Tx' of this transform Tx maps coordinates transformed by Tx back to their original coordinates. In other words, Tx'(Tx(p)) = p = Tx(Tx'(p)).If this transform maps all coordinates onto a point or a line then it will not have an inverse, since coordinates that do not lie on the destination point or line will not have an inverse mapping. The
getDeterminant
method can be used to determine if this transform has no inverse, in which case an exception will be thrown if thecreateInverse
method is called.- Returns:
- a new
AffineTransform
object representing the inverse transformation. - Throws:
NoninvertibleTransformException
- if the matrix cannot be inverted.- Since:
- 1.2
- See Also:
-
invert
Sets this transform to the inverse of itself. The inverse transform Tx' of this transform Tx maps coordinates transformed by Tx back to their original coordinates. In other words, Tx'(Tx(p)) = p = Tx(Tx'(p)).If this transform maps all coordinates onto a point or a line then it will not have an inverse, since coordinates that do not lie on the destination point or line will not have an inverse mapping. The
getDeterminant
method can be used to determine if this transform has no inverse, in which case an exception will be thrown if theinvert
method is called.- Throws:
NoninvertibleTransformException
- if the matrix cannot be inverted.- Since:
- 1.6
- See Also:
-
transform
Transforms the specifiedptSrc
and stores the result inptDst
. IfptDst
isnull
, a newPoint2D
object is allocated and then the result of the transformation is stored in this object. In either case,ptDst
, which contains the transformed point, is returned for convenience. IfptSrc
andptDst
are the same object, the input point is correctly overwritten with the transformed point.- Parameters:
ptSrc
- the specifiedPoint2D
to be transformedptDst
- the specifiedPoint2D
that stores the result of transformingptSrc
- Returns:
- the
ptDst
after transformingptSrc
and storing the result inptDst
. - Since:
- 1.2
-
transform
Transforms an array of point objects by this transform. If any element of theptDst
array isnull
, a newPoint2D
object is allocated and stored into that element before storing the results of the transformation.Note that this method does not take any precautions to avoid problems caused by storing results into
Point2D
objects that will be used as the source for calculations further down the source array. This method does guarantee that if a specifiedPoint2D
object is both the source and destination for the same single point transform operation then the results will not be stored until the calculations are complete to avoid storing the results on top of the operands. If, however, the destinationPoint2D
object for one operation is the same object as the sourcePoint2D
object for another operation further down the source array then the original coordinates in that point are overwritten before they can be converted.- Parameters:
ptSrc
- the array containing the source point objectssrcOff
- the offset to the first point object to be transformed in the source arrayptDst
- the array into which the transform point objects are returneddstOff
- the offset to the location of the first transformed point object that is stored in the destination arraynumPts
- the number of point objects to be transformed- Since:
- 1.2
-
transform
public void transform(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms an array of floating point coordinates by this transform. The two coordinate array sections can be exactly the same or can be overlapping sections of the same array without affecting the validity of the results. This method ensures that no source coordinates are overwritten by a previous operation before they can be transformed. The coordinates are stored in the arrays starting at the specified offset in the order[x0, y0, x1, y1, ..., xn, yn]
.- Parameters:
srcPts
- the array containing the source point coordinates. Each point is stored as a pair of x, y coordinates.srcOff
- the offset to the first point to be transformed in the source arraydstPts
- the array into which the transformed point coordinates are returned. Each point is stored as a pair of x, y coordinates.dstOff
- the offset to the location of the first transformed point that is stored in the destination arraynumPts
- the number of points to be transformed- Since:
- 1.2
-
transform
public void transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms an array of double precision coordinates by this transform. The two coordinate array sections can be exactly the same or can be overlapping sections of the same array without affecting the validity of the results. This method ensures that no source coordinates are overwritten by a previous operation before they can be transformed. The coordinates are stored in the arrays starting at the indicated offset in the order[x0, y0, x1, y1, ..., xn, yn]
.- Parameters:
srcPts
- the array containing the source point coordinates. Each point is stored as a pair of x, y coordinates.srcOff
- the offset to the first point to be transformed in the source arraydstPts
- the array into which the transformed point coordinates are returned. Each point is stored as a pair of x, y coordinates.dstOff
- the offset to the location of the first transformed point that is stored in the destination arraynumPts
- the number of point objects to be transformed- Since:
- 1.2
-
transform
public void transform(float[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms an array of floating point coordinates by this transform and stores the results into an array of doubles. The coordinates are stored in the arrays starting at the specified offset in the order[x0, y0, x1, y1, ..., xn, yn]
.- Parameters:
srcPts
- the array containing the source point coordinates. Each point is stored as a pair of x, y coordinates.srcOff
- the offset to the first point to be transformed in the source arraydstPts
- the array into which the transformed point coordinates are returned. Each point is stored as a pair of x, y coordinates.dstOff
- the offset to the location of the first transformed point that is stored in the destination arraynumPts
- the number of points to be transformed- Since:
- 1.2
-
transform
public void transform(double[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms an array of double precision coordinates by this transform and stores the results into an array of floats. The coordinates are stored in the arrays starting at the specified offset in the order[x0, y0, x1, y1, ..., xn, yn]
.- Parameters:
srcPts
- the array containing the source point coordinates. Each point is stored as a pair of x, y coordinates.srcOff
- the offset to the first point to be transformed in the source arraydstPts
- the array into which the transformed point coordinates are returned. Each point is stored as a pair of x, y coordinates.dstOff
- the offset to the location of the first transformed point that is stored in the destination arraynumPts
- the number of point objects to be transformed- Since:
- 1.2
-
inverseTransform
public Point2D inverseTransform(Point2D ptSrc, Point2D ptDst) throws NoninvertibleTransformException Inverse transforms the specifiedptSrc
and stores the result inptDst
. IfptDst
isnull
, a newPoint2D
object is allocated and then the result of the transform is stored in this object. In either case,ptDst
, which contains the transformed point, is returned for convenience. IfptSrc
andptDst
are the same object, the input point is correctly overwritten with the transformed point.- Parameters:
ptSrc
- the point to be inverse transformedptDst
- the resulting transformed point- Returns:
ptDst
, which contains the result of the inverse transform.- Throws:
NoninvertibleTransformException
- if the matrix cannot be inverted.- Since:
- 1.2
-
inverseTransform
public void inverseTransform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) throws NoninvertibleTransformException Inverse transforms an array of double precision coordinates by this transform. The two coordinate array sections can be exactly the same or can be overlapping sections of the same array without affecting the validity of the results. This method ensures that no source coordinates are overwritten by a previous operation before they can be transformed. The coordinates are stored in the arrays starting at the specified offset in the order[x0, y0, x1, y1, ..., xn, yn]
.- Parameters:
srcPts
- the array containing the source point coordinates. Each point is stored as a pair of x, y coordinates.srcOff
- the offset to the first point to be transformed in the source arraydstPts
- the array into which the transformed point coordinates are returned. Each point is stored as a pair of x, y coordinates.dstOff
- the offset to the location of the first transformed point that is stored in the destination arraynumPts
- the number of point objects to be transformed- Throws:
NoninvertibleTransformException
- if the matrix cannot be inverted.- Since:
- 1.2
-
deltaTransform
Transforms the relative distance vector specified byptSrc
and stores the result inptDst
. A relative distance vector is transformed without applying the translation components of the affine transformation matrix using the following equations:[ x' ] [ m00 m01 (m02) ] [ x ] [ m00x + m01y ] [ y' ] = [ m10 m11 (m12) ] [ y ] = [ m10x + m11y ] [ (1) ] [ (0) (0) ( 1 ) ] [ (1) ] [ (1) ]
IfptDst
isnull
, a newPoint2D
object is allocated and then the result of the transform is stored in this object. In either case,ptDst
, which contains the transformed point, is returned for convenience. IfptSrc
andptDst
are the same object, the input point is correctly overwritten with the transformed point.- Parameters:
ptSrc
- the distance vector to be delta transformedptDst
- the resulting transformed distance vector- Returns:
ptDst
, which contains the result of the transformation.- Since:
- 1.2
-
deltaTransform
public void deltaTransform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms an array of relative distance vectors by this transform. A relative distance vector is transformed without applying the translation components of the affine transformation matrix using the following equations:[ x' ] [ m00 m01 (m02) ] [ x ] [ m00x + m01y ] [ y' ] = [ m10 m11 (m12) ] [ y ] = [ m10x + m11y ] [ (1) ] [ (0) (0) ( 1 ) ] [ (1) ] [ (1) ]
The two coordinate array sections can be exactly the same or can be overlapping sections of the same array without affecting the validity of the results. This method ensures that no source coordinates are overwritten by a previous operation before they can be transformed. The coordinates are stored in the arrays starting at the indicated offset in the order[x0, y0, x1, y1, ..., xn, yn]
.- Parameters:
srcPts
- the array containing the source distance vectors. Each vector is stored as a pair of relative x, y coordinates.srcOff
- the offset to the first vector to be transformed in the source arraydstPts
- the array into which the transformed distance vectors are returned. Each vector is stored as a pair of relative x, y coordinates.dstOff
- the offset to the location of the first transformed vector that is stored in the destination arraynumPts
- the number of vector coordinate pairs to be transformed- Since:
- 1.2
-
createTransformedShape
Returns a newShape
object defined by the geometry of the specifiedShape
after it has been transformed by this transform.- Parameters:
pSrc
- the specifiedShape
object to be transformed by this transform.- Returns:
- a new
Shape
object that defines the geometry of the transformedShape
, or null ifpSrc
is null. - Since:
- 1.2
-
toString
-
isIdentity
public boolean isIdentity()Returnstrue
if thisAffineTransform
is an identity transform.- Returns:
true
if thisAffineTransform
is an identity transform;false
otherwise.- Since:
- 1.2
-
clone
-
hashCode
-
equals
Returnstrue
if thisAffineTransform
represents the same affine coordinate transform as the specified argument.
-