Color

@Immutable class Color
kotlin.Any
   ↳ androidx.ui.graphics.Color

The Color class contains color information to be used while painting in Canvas. Color supports ColorSpaces with 3 components, plus one for alpha.

Creating

Color can be created with one of these methods:

    // from 4 separate [Float] components. Alpha and ColorSpace are optional
    val rgbaWhiteFloat = Color(red = 1f, green = 1f, blue = 1f, alpha = 1f,
        ColorSpace.get(ColorSpaces.Srgb))

    // from a 32-bit SRGB color integer
    val fromIntWhite = Color(android.graphics.Color.WHITE)
    val fromLongBlue = Color(0xFF0000FF)

    // from SRGB integer component values. Alpha is optional
    val rgbaWhiteInt = Color(red = 0xFF, green = 0xFF, blue = 0xFF, alpha = 0xFF)

Representation

A Color always defines a color using 4 components packed in a single 64 bit long value. One of these components is always alpha while the other three components depend on the color space's color model. The most common color model is the RGB model in which the components represent red, green, and blue values.

Component ranges: the ranges defined in the tables below indicate the ranges that can be encoded in a color long. They do not represent the actual ranges as they may differ per color space. For instance, the RGB components of a color in the Display P3 color space use the [0..1] range. Please refer to the documentation of the various color spaces to find their respective ranges.

Alpha range: while alpha is encoded in a color long using a 10 bit integer (thus using a range of [0..1023]), it is converted to and from [0..1] float values when decoding and encoding color longs.

sRGB color space: for compatibility reasons and ease of use, Color encoded sRGB colors do not use the same encoding as other color longs.

| Component | Name        | Size    | Range                 |
|-----------|-------------|---------|-----------------------|
| [RGB][ColorSpace.Model.Rgb] color model |
| R         | Red         | 16 bits | `[-65504.0, 65504.0]` |
| G         | Green       | 16 bits | `[-65504.0, 65504.0]` |
| B         | Blue        | 16 bits | `[-65504.0, 65504.0]` |
| A         | Alpha       | 10 bits | `[0..1023]`           |
|           | Color space | 6 bits  | `[0..63]`             |
| [SRGB][ColorSpaces.Srgb] color space |
| R         | Red         | 8 bits  | `[0..255]`            |
| G         | Green       | 8 bits  | `[0..255]`            |
| B         | Blue        | 8 bits  | `[0..255]`            |
| A         | Alpha       | 8 bits  | `[0..255]`            |
| X         | Unused      | 32 bits | `[0]`                 |
| [XYZ][ColorSpace.Model.Xyz] color model |
| X         | X           | 16 bits | `[-65504.0, 65504.0]` |
| Y         | Y           | 16 bits | `[-65504.0, 65504.0]` |
| Z         | Z           | 16 bits | `[-65504.0, 65504.0]` |
| A         | Alpha       | 10 bits | `[0..1023]`           |
|           | Color space | 6 bits  | `[0..63]`             |
| [Lab][ColorSpace.Model.Lab] color model |
| L         | L           | 16 bits | `[-65504.0, 65504.0]` |
| a         | a           | 16 bits | `[-65504.0, 65504.0]` |
| b         | b           | 16 bits | `[-65504.0, 65504.0]` |
| A         | Alpha       | 10 bits | `[0..1023]`           |
|           | Color space | 6 bits  | `[0..63]`             |

The components in this table are listed in encoding order (see below), which is why color longs in the RGB model are called RGBA colors (even if this doesn't quite hold for the special case of sRGB colors).

The color encoding relies on half-precision float values (fp16). If you wish to know more about the limitations of half-precision float values, please refer to the documentation of the Float16 class.

The values returned by these methods depend on the color space encoded in the color long. The values are however typically in the [0..1] range for RGB colors. Please refer to the documentation of the various color spaces for the exact ranges.

Summary

Public methods

Color
convert(colorSpace: ColorSpace)

Converts this color from its color space to the specified color space.

Color
copy(alpha: Float = this.alpha, red: Float = this.red, green: Float = this.green, blue: Float = this.blue)

Copies the existing color, changing only the provided values.

Boolean
equals(other: Any?)

Int

String

Returns a string representation of the object.

Extension functions

From androidx.ui.graphics
Float

Returns the relative luminance of this color.

Int

Converts this color to an ARGB color int.

Properties

Float

Returns the value of the alpha component in the range [0..1].

Float

Returns the value of the blue component in the range defined by this color's color space (see ColorSpace.getMinValue and ColorSpace.getMaxValue).

ColorSpace

Returns this color's color space.

Float

Returns the value of the green component in the range defined by this color's color space (see ColorSpace.getMinValue and ColorSpace.getMaxValue).

Float

Returns the value of the red component in the range defined by this color's color space (see ColorSpace.getMinValue and ColorSpace.getMaxValue).

Long

Companion properties

Color

Color

Color

Color

Color

Color

Color

Color

Color

Color

Color

Color

Public methods

convert

fun convert(colorSpace: ColorSpace): Color

Converts this color from its color space to the specified color space. The conversion is done using the default rendering intent as specified by ColorSpace.connect.

Parameters
colorSpace: ColorSpace The destination color space, cannot be null
Return
A non-null color instance in the specified color space

copy

fun copy(
    alpha: Float = this.alpha,
    red: Float = this.red,
    green: Float = this.green,
    blue: Float = this.blue
): Color

Copies the existing color, changing only the provided values. The ColorSpace of the returned Color is the same as this colorSpace.

equals

fun equals(other: Any?): Boolean

hashCode

fun hashCode(): Int

toString

fun toString(): String

Returns a string representation of the object. This method returns a string equal to the value of:

    "Color($r, $g, $b, $a, ${colorSpace.name})"

For instance, the string representation of opaque black in the sRGB color space is equal to the following value:

    Color(0.0, 0.0, 0.0, 1.0, sRGB IEC61966-2.1)
Return
A non-null string representation of the object

Properties

alpha

val alpha: Float

Returns the value of the alpha component in the range [0..1].

See Also

blue

val blue: Float

Returns the value of the blue component in the range defined by this color's color space (see ColorSpace.getMinValue and ColorSpace.getMaxValue).

If this color's color model is not RGB, calling this is the third component of the ColorSpace.

See Also

colorSpace

val colorSpace: ColorSpace

Returns this color's color space.

Return
A non-null instance of ColorSpace

green

val green: Float

Returns the value of the green component in the range defined by this color's color space (see ColorSpace.getMinValue and ColorSpace.getMaxValue).

If this color's color model is not RGB, calling this is the second component of the ColorSpace.

See Also

red

val red: Float

Returns the value of the red component in the range defined by this color's color space (see ColorSpace.getMinValue and ColorSpace.getMaxValue).

If this color's color model is not RGB, calling this is the first component of the ColorSpace.

See Also

value

val value: Long

Companion properties

Black

val Black: Color

Blue

val Blue: Color

Cyan

val Cyan: Color

DarkGray

val DarkGray: Color

Gray

val Gray: Color

Green

val Green: Color

LightGray

val LightGray: Color

Magenta

val Magenta: Color

Red

val Red: Color

Transparent

val Transparent: Color

White

val White: Color

Yellow

val Yellow: Color