MutableAffineTransform
class MutableAffineTransform : AffineTransform
An affine transformation in the plane. The transformation can be thought of as a 3x3 matrix:
⎡m00 m10 m20⎤
⎢m01 m11 m21⎥
⎣ 0 0 1 ⎦
Applying the transformation can be thought of as a matrix multiplication, with the to-be-transformed point represented as a column vector with an extra 1:
⎡m00 m10 m20⎤ ⎡x⎤ ⎡m00*x + m10*y + m20⎤
⎢m01 m11 m21⎥ * ⎢y⎥ = ⎢m01*x + m11*y + m21⎥
⎣ 0 0 1 ⎦ ⎣1⎦ ⎣ 1 ⎦
Transformations are composed via multiplication. Multiplication is not commutative (i.e. AB != BA), and the left-hand transformation is composed "after" the right hand transformation. E.g., if you have:
val rotate = ImmutableAffineTransform.rotate(Angle.degreesToRadians(45))
val translate = ImmutableAffineTransform.translate(Vec(10, 0))
then rotate * translate first translates 10 units in the positive x-direction, then rotates 45° about the origin.
See ImmutableAffineTransform for an immutable alternative to this class.
Summary
Public constructors |
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Constructs an identity |
Public functions |
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open operator Boolean |
Component-wise equality operator for |
open Int |
hashCode() |
Unit |
setValues(values: @Size(min = 6) FloatArray)Like |
Unit |
Populates this transform with the given values, starting with the top left corner of the matrix and proceeding in row-major order. |
open String |
toString() |
Inherited functions |
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Public constructors
MutableAffineTransform
MutableAffineTransform()
Constructs an identity MutableAffineTransform:
⎡1 0 0⎤
⎢0 1 0⎥
⎣0 0 1⎦
This is useful when pre-allocating a scratch instance to be filled later.
Public functions
equals
open operator fun equals(other: Any?): Boolean
Component-wise equality operator for MutableAffineTransform.
Due to the propagation floating point precision errors, operations that may be equivalent over the real numbers are not always equivalent for floats, and might return false for equals in some cases.
setValues
fun setValues(values: @Size(min = 6) FloatArray): Unit
Like setValues, but accepts a FloatArray instead of individual float values.
setValues
fun setValues(m00: Float, m10: Float, m20: Float, m01: Float, m11: Float, m21: Float): Unit
Populates this transform with the given values, starting with the top left corner of the matrix and proceeding in row-major order.
Prefer to modify this object with functions that apply specific transform operations, such as populateFromScale or populateFromRotate, rather than directly setting the actual numeric values of this transform. This function is useful for when the values are needed to be provided in bulk, for example for serialization.
To access these values in the same order as they are set here, use AffineTransform.getValues.