Matrix44
open class Matrix44
| kotlin.Any | |
| ↳ | android.graphics.Matrix44 |
The Matrix44 class holds a 4x4 matrix for transforming coordinates. It is similar to Matrix, and should be used when you want to manipulate the canvas in 3D. Values are kept in row-major order. The values and operations are treated as column vectors.
Summary
| Public constructors | |
|---|---|
Matrix44()The default Matrix44 constructor will instantiate an identity matrix. |
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Creates and returns a Matrix44 by taking the 3x3 Matrix and placing it on the 0 of the z-axis by setting row [ a b c ] [ a b 0 c ] [ d e f ] -> [ d e 0 f ] [ g h i ] [ 0 0 1 0 ] [ g h 0 i ] |
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| Public methods | |
|---|---|
| open Matrix44 |
Multiplies `this` matrix (A) and provided Matrix (B) in the order of A * B. |
| open Boolean |
Indicates whether some other object is "equal to" this one. |
| open Float |
Gets the value at the matrix's row and column. |
| open Unit |
getValues(dst: FloatArray)Copies matrix values into the provided array in row-major order. |
| open Int |
hashCode()Returns a hash code value for the object. |
| open Boolean |
invert()Inverts the Matrix44, then return true if successful, false if unable to invert. |
| open Boolean |
Returns true if Matrix44 is equal to identity matrix. |
| open FloatArray |
Multiplies (x, y, z, w) vector by the Matrix44, then returns the new (x, y, z, w). |
| open Unit |
Multiplies (x, y, z, w) vector by the Matrix44, then returns the new (x, y, z, w). |
| open Unit |
reset()Sets the Matrix44 to the identity matrix. |
| open Matrix44 |
Applies a rotation around a given axis, then returns self. |
| open Matrix44 |
Applies scaling factors to `this` Matrix44, then returns self. |
| open Unit |
Sets the value at the matrix's row and column to the provided value. |
| open Unit |
setValues(src: FloatArray)Replaces the Matrix's values with the values in the provided array. |
| open String |
toString()Returns a string representation of the object. |
| open Matrix44 |
Applies a translation to `this` Matrix44, then returns self. |
Public constructors
Matrix44
Matrix44()
The default Matrix44 constructor will instantiate an identity matrix.
Matrix44
Matrix44(mat: Matrix)
Creates and returns a Matrix44 by taking the 3x3 Matrix and placing it on the 0 of the z-axis by setting row 2 and column 2 to the identity as seen in the following operation:
[ a b c ] [ a b 0 c ] [ d e f ] -> [ d e 0 f ] [ g h i ] [ 0 0 1 0 ] [ g h 0 i ]
| Parameters | |
|---|---|
mat |
Matrix: A 3x3 Matrix to be converted (original Matrix will not be changed). This value cannot be null. |
Public methods
concat
open fun concat(b: Matrix44): Matrix44
Multiplies `this` matrix (A) and provided Matrix (B) in the order of A * B. The result is saved in `this` Matrix.
| Parameters | |
|---|---|
b |
Matrix44: The second Matrix in the concatenation operation. This value cannot be null. |
| Return | |
|---|---|
Matrix44 |
A reference to this Matrix, which can be used to chain Matrix operations. This value cannot be null. |
equals
open fun equals(other: Any?): Boolean
Indicates whether some other object is "equal to" this one.
The equals method implements an equivalence relation on non-null object references:
- It is reflexive: for any non-null reference value
x,x.equals(x)should returntrue. - It is symmetric: for any non-null reference values
xandy,x.equals(y)should returntrueif and only ify.equals(x)returnstrue. - It is transitive: for any non-null reference values
x,y, andz, ifx.equals(y)returnstrueandy.equals(z)returnstrue, thenx.equals(z)should returntrue. - It is consistent: for any non-null reference values
xandy, multiple invocations ofx.equals(y)consistently returntrueor consistently returnfalse, provided no information used inequalscomparisons on the objects is modified. - For any non-null reference value
x,x.equals(null)should returnfalse.
An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.
| Parameters | |
|---|---|
obj |
the reference object with which to compare. |
| Return | |
|---|---|
Boolean |
true if this object is the same as the obj argument; false otherwise. |
get
open fun get(
row: Int,
col: Int
): Float
Gets the value at the matrix's row and column.
| Parameters | |
|---|---|
row |
Int: An integer from 0 to 3 indicating the row of the value to get. Value is between 0 and 3 inclusive |
col |
Int: An integer from 0 to 3 indicating the column of the value to get. Value is between 0 and 3 inclusive |
getValues
open fun getValues(dst: FloatArray): Unit
Copies matrix values into the provided array in row-major order.
| Parameters | |
|---|---|
dst |
FloatArray: The float array where values will be copied, must be of length 16. This value cannot be null. |
| Exceptions | |
|---|---|
java.lang.IllegalArgumentException |
if the destination float array is not of length 16 |
hashCode
open fun hashCode(): Int
Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.
The general contract of hashCode is:
- Whenever it is invoked on the same object more than once during an execution of a Java application, the
hashCodemethod must consistently return the same integer, provided no information used inequalscomparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. - If two objects are equal according to the
equalsmethod, then calling thehashCodemethod on each of the two objects must produce the same integer result. - It is not required that if two objects are unequal according to the
equalsmethod, then calling thehashCodemethod on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
| Return | |
|---|---|
Int |
a hash code value for this object. |
invert
open fun invert(): Boolean
Inverts the Matrix44, then return true if successful, false if unable to invert.
| Return | |
|---|---|
Boolean |
true on success, false otherwise |
isIdentity
open fun isIdentity(): Boolean
Returns true if Matrix44 is equal to identity matrix.
map
open fun map(
x: Float,
y: Float,
z: Float,
w: Float
): FloatArray
Multiplies (x, y, z, w) vector by the Matrix44, then returns the new (x, y, z, w). Users should set w to 1 to indicate the coordinates are normalized.
| Return | |
|---|---|
FloatArray |
An array of length 4 that represents the x, y, z, w (where w is perspective) value after multiplying x, y, z, 1 by the matrix. This value cannot be null. |
map
open fun map(
x: Float,
y: Float,
z: Float,
w: Float,
dst: FloatArray
): Unit
Multiplies (x, y, z, w) vector by the Matrix44, then returns the new (x, y, z, w). Users should set w to 1 to indicate the coordinates are normalized.
| Parameters | |
|---|---|
dst |
FloatArray: This value cannot be null. |
rotate
open fun rotate(
deg: Float,
xComp: Float,
yComp: Float,
zComp: Float
): Matrix44
Applies a rotation around a given axis, then returns self. x, y, z represent the axis by which to rotate around. For example, pass in 1, 0, 0 to rotate around the x-axis. The axis provided will be normalized.
| Parameters | |
|---|---|
deg |
Float: Amount in degrees to rotate the matrix about the x-axis |
xComp |
Float: X component of the rotation axis |
yComp |
Float: Y component of the rotation axis |
zComp |
Float: Z component of the rotation axis |
| Return | |
|---|---|
Matrix44 |
A reference to this Matrix, which can be used to chain Matrix operations. This value cannot be null. |
scale
open fun scale(
x: Float,
y: Float,
z: Float
): Matrix44
Applies scaling factors to `this` Matrix44, then returns self. Pass 1s for no change.
| Parameters | |
|---|---|
x |
Float: Scaling factor for the x-axis |
y |
Float: Scaling factor for the y-axis |
z |
Float: Scaling factor for the z-axis |
| Return | |
|---|---|
Matrix44 |
A reference to this Matrix, which can be used to chain Matrix operations. This value cannot be null. |
set
open fun set(
row: Int,
col: Int,
val: Float
): Unit
Sets the value at the matrix's row and column to the provided value.
| Parameters | |
|---|---|
row |
Int: An integer from 0 to 3 indicating the row of the value to change. Value is between 0 and 3 inclusive |
col |
Int: An integer from 0 to 3 indicating the column of the value to change. Value is between 0 and 3 inclusive |
val |
Float: The value the element at the specified index will be set to |
setValues
open fun setValues(src: FloatArray): Unit
Replaces the Matrix's values with the values in the provided array.
| Parameters | |
|---|---|
src |
FloatArray: A float array of length 16. Floats are treated in row-major order. This value cannot be null. |
| Exceptions | |
|---|---|
java.lang.IllegalArgumentException |
if the destination float array is not of length 16 |
toString
open fun toString(): String
Returns a string representation of the object.
| Return | |
|---|---|
String |
a string representation of the object. |
translate
open fun translate(
x: Float,
y: Float,
z: Float
): Matrix44
Applies a translation to `this` Matrix44, then returns self.
| Parameters | |
|---|---|
x |
Float: Translation for the x-axis |
y |
Float: Translation for the y-axis |
z |
Float: Translation for the z-axis |
| Return | |
|---|---|
Matrix44 |
A reference to this Matrix, which can be used to chain Matrix operations. This value cannot be null. |