DiscreteRotation

Artifact: androidx.camera:camera-common

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Added in 1.7.0-alpha03

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Kotlin |Java

value class DiscreteRotation

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A value class representing a rotation constrained to 90-degree increments (0, 90, 180, or 270 degrees).

This class provides utility functions for performing modulo-360 arithmetic on rotations (addition and subtraction), as well as rounding arbitrary rotation values to the nearest 90-degree step.

Summary

Public companion functions
DiscreteRotation	from(degrees: Int) Creates a DiscreteRotation from the given integer degrees.
DiscreteRotation	fromSurfaceRotation(surfaceRotation: Int) Creates a DiscreteRotation from a Surface rotation constant.
DiscreteRotation	round(degrees: Float) Rounds degrees to the nearest DiscreteRotation (0, 90, 180, or 270).
DiscreteRotation	round(degrees: Int) Rounds degrees to the nearest DiscreteRotation (0, 90, 180, or 270).

Public companion properties
DiscreteRotation	ROTATION_0 A DiscreteRotation of 0 degrees.
DiscreteRotation	ROTATION_180 A DiscreteRotation of 180 degrees.
DiscreteRotation	ROTATION_270 A DiscreteRotation of 270 degrees.
DiscreteRotation	ROTATION_90 A DiscreteRotation of 90 degrees.

Public functions
inline operator DiscreteRotation	minus(degrees: Int) Subtracts the specified number of degrees from this rotation.
inline operator DiscreteRotation	minus(other: DiscreteRotation) Subtracts another DiscreteRotation from this rotation.
inline operator DiscreteRotation	plus(degrees: Int) Adds the specified number of degrees to this rotation.
inline operator DiscreteRotation	plus(other: DiscreteRotation) Adds another DiscreteRotation to this rotation.
open String	toString()

Public properties
Int	degrees The rotation value in degrees.

Public companion functions

from

Added in 1.7.0-alpha03

fun from(degrees: Int): DiscreteRotation

Creates a DiscreteRotation from the given integer degrees.

Parameters
degrees: Int	The rotation in degrees. Must be one of 0, 90, 180, or 270.

Returns
DiscreteRotation	A DiscreteRotation representing the specified degrees.

Throws
IllegalArgumentException	If degrees is not a valid discrete rotation (0, 90, 180, or 270).

fromSurfaceRotation

Added in 1.7.0-alpha03

fun fromSurfaceRotation(surfaceRotation: Int): DiscreteRotation

Creates a DiscreteRotation from a Surface rotation constant.

Rotation values are relative to the device's natural orientation, Surface.ROTATION_0.

Parameters
surfaceRotation: Int	A Surface rotation value. Must be one of the SurfaceRotation constants (e.g., Surface.ROTATION_90).

Returns
DiscreteRotation	The corresponding DiscreteRotation.

Throws
IllegalArgumentException	If the provided surfaceRotation is not valid.

round

Added in 1.7.0-alpha03

fun round(degrees: Float): DiscreteRotation

Rounds degrees to the nearest DiscreteRotation (0, 90, 180, or 270).

Negative values are normalized and rounded to the nearest positive DiscreteRotation (e.g., -90.0f rounds to 270, and -45.0f rounds to 0). Boundary values (e.g., 45.0f) are rounded up to the nearest 90-degree increment (e.g., 45.0f rounds to 90).

Parameters
degrees: Float	The rotation in degrees to round.

Returns
DiscreteRotation	The rounded DiscreteRotation.

round

Added in 1.7.0-alpha03

fun round(degrees: Int): DiscreteRotation

Rounds degrees to the nearest DiscreteRotation (0, 90, 180, or 270).

Negative values are normalized and rounded to the nearest positive DiscreteRotation (e.g., -90 rounds to 270, and -45 rounds to 0). Boundary values (e.g., 45) are rounded up to the nearest 90-degree increment (e.g., 45 rounds to 90).

Parameters
degrees: Int	The rotation in degrees to round.

Returns
DiscreteRotation	The rounded DiscreteRotation.

Public companion properties

ROTATION_0

val ROTATION_0: DiscreteRotation

A DiscreteRotation of 0 degrees.

ROTATION_180

val ROTATION_180: DiscreteRotation

A DiscreteRotation of 180 degrees.

ROTATION_270

val ROTATION_270: DiscreteRotation

A DiscreteRotation of 270 degrees.

ROTATION_90

val ROTATION_90: DiscreteRotation

A DiscreteRotation of 90 degrees.

Public functions

minus

Added in 1.7.0-alpha03

inline operator fun minus(degrees: Int): DiscreteRotation

Subtracts the specified number of degrees from this rotation.

The result is normalized to the range [0, 360) degrees.

Parameters
degrees: Int	The degrees to subtract. Must be a valid discrete rotation (0, 90, 180, or 270).

Returns
DiscreteRotation	The resulting DiscreteRotation.

Throws
IllegalArgumentException	If degrees is not a valid discrete rotation (0, 90, 180, or 270).

minus

Added in 1.7.0-alpha03

inline operator fun minus(other: DiscreteRotation): DiscreteRotation

Subtracts another DiscreteRotation from this rotation.

The result is normalized to the range [0, 360) degrees.

Parameters
other: DiscreteRotation	The DiscreteRotation to subtract.

Returns
DiscreteRotation	The resulting DiscreteRotation.

plus

Added in 1.7.0-alpha03

inline operator fun plus(degrees: Int): DiscreteRotation

Adds the specified number of degrees to this rotation.

The result is normalized to the range [0, 360) degrees.

Parameters
degrees: Int	The degrees to add. Must be a valid discrete rotation (0, 90, 180, or 270).

Returns
DiscreteRotation	The resulting DiscreteRotation.

Throws
IllegalArgumentException	If degrees is not a valid discrete rotation (0, 90, 180, or 270).

plus

Added in 1.7.0-alpha03

inline operator fun plus(other: DiscreteRotation): DiscreteRotation

Adds another DiscreteRotation to this rotation.

The result is normalized to the range [0, 360) degrees.

Parameters
other: DiscreteRotation	The DiscreteRotation to add.

Returns
DiscreteRotation	The resulting DiscreteRotation.

toString

open fun toString(): String

Public properties

degrees

Added in 1.7.0-alpha03

val degrees: Int

The rotation value in degrees. Guaranteed to be one of 0, 90, 180, or 270.