skiko/org.jetbrains.skia/BlendMode

BlendMode

Blends are operators that take in two colors (source, destination) and return a new color. Many of these operate the same on all 4 components: red, green, blue, alpha. For these, we just document what happens to one component, rather than naming each one separately.

Different SkColorTypes have different representations for color components: 8-bit: 0..255 6-bit: 0..63 5-bit: 0..31 4-bit: 0..15 floats: 0...1

The documentation is expressed as if the component values are always 0..1 (floats).

For brevity, the documentation uses the following abbreviations s : source d : destination sa : source alpha da : destination alpha

Results are abbreviated r : if all 4 components are computed in the same manner ra : result alpha component rc : result "color": red, green, blue components

Entries

CLEAR

Replaces destination with zero: fully transparent. r = 0

SRC

Replaces destination. r = s

DST

Preserves destination. r = d

SRC_OVER

Source over destination. r = s + (1-sa)*d

DST_OVER

Destination over source. r = d + (1-da)*s

SRC_IN

Source trimmed inside destination. r = s * da

DST_IN

Destination trimmed by source. r = d * sa

SRC_OUT

Source trimmed outside destination. r = s * (1-da)

DST_OUT

Destination trimmed outside source. r = d * (1-sa)

SRC_ATOP

Source inside destination blended with destination. r = sda + d(1-sa)

DST_ATOP

Destination inside source blended with source. r = dsa + s(1-da)

XOR

Each of source and destination trimmed outside the other. r = s*(1-da) + d*(1-sa)

PLUS

Sum of colors. r = min(s + d, 1)

MODULATE

Product of premultiplied colors; darkens destination. r = s*d

SCREEN

Multiply inverse of pixels, inverting result; brightens destination. r = s + d - s*d

OVERLAY

Multiply or screen, depending on destination.

DARKEN

Darker of source and destination. rc = s + d - max(sda, dsa), ra = kSrcOver

LIGHTEN

Lighter of source and destination. rc = s + d - min(sda, dsa), ra = kSrcOver

COLOR_DODGE

Brighten destination to reflect source.

COLOR_BURN

Darken destination to reflect source.

HARD_LIGHT

Multiply or screen, depending on source.

SOFT_LIGHT

Lighten or darken, depending on source.

DIFFERENCE

Subtract darker from lighter with higher contrast. rc = s + d - 2*(min(sda, dsa)), ra = kSrcOver

EXCLUSION

Subtract darker from lighter with lower contrast. rc = s + d - two(s*d), ra = kSrcOver

MULTIPLY

Multiply source with destination, darkening image. r = s*(1-da) + d*(1-sa) + s*d

HUE

Hue of source with saturation and luminosity of destination.

SATURATION

Saturation of source with hue and luminosity of destination.

COLOR

Hue and saturation of source with luminosity of destination.

LUMINOSITY

Luminosity of source with hue and saturation of destination.

Properties

entries

val entries: EnumEntries<BlendMode>

Returns a representation of an immutable list of all enum entries, in the order they're declared.

name

val name: String

ordinal

val ordinal: Int

Functions

valueOf

fun valueOf(value: String): BlendMode

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

values

fun values(): Array<BlendMode>

Returns an array containing the constants of this enum type, in the order they're declared.