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blend
BlendMode

BlendMode

Mojo struct 🡭

BlendMode

@memory_only
struct BlendMode

How a drawn color combines with the pixel underneath.

SOURCE_OVER, the default, is ordinary alpha compositing: the source covers the backdrop in proportion to its alpha. The rest are the other twelve Porter-Duff operators, the eleven separable blend modes and the four non-separable ones; see this module’s docstring for the formula each one applies.

Aliases

  • SOURCE_OVER = BlendMode(Int(0))
  • SOURCE = BlendMode(Int(1))
  • DESTINATION_IN = BlendMode(Int(2))
  • DESTINATION_OUT = BlendMode(Int(3))
  • XOR = BlendMode(Int(4))
  • CLEAR = BlendMode(Int(5))
  • DESTINATION = BlendMode(Int(6))
  • DESTINATION_OVER = BlendMode(Int(7))
  • SOURCE_IN = BlendMode(Int(8))
  • SOURCE_OUT = BlendMode(Int(9))
  • SOURCE_ATOP = BlendMode(Int(10))
  • DESTINATION_ATOP = BlendMode(Int(11))
  • ADD = BlendMode(Int(12))
  • MULTIPLY = BlendMode(Int(13))
  • SCREEN = BlendMode(Int(14))
  • OVERLAY = BlendMode(Int(15))
  • DARKEN = BlendMode(Int(16))
  • LIGHTEN = BlendMode(Int(17))
  • DIFFERENCE = BlendMode(Int(18))
  • EXCLUSION = BlendMode(Int(19))
  • COLOR_DODGE = BlendMode(Int(20))
  • COLOR_BURN = BlendMode(Int(21))
  • HARD_LIGHT = BlendMode(Int(22))
  • SOFT_LIGHT = BlendMode(Int(23))
  • HUE = BlendMode(Int(24))
  • SATURATION = BlendMode(Int(25))
  • COLOR = BlendMode(Int(26))
  • LUMINOSITY = BlendMode(Int(27))

Implemented traits

AnyType, Copyable, Deinitable, Equatable, ImplicitlyCopyable, Movable, Writable

Methods

__init__ 

fn def __init__(out self, value: Int)

Prefer the comptime constants over constructing one directly.

Args:

  • value (Int): 0 SOURCE_OVER, 1 SOURCE, 2 DESTINATION_IN, 3 DESTINATION_OUT, 4 XOR, 5 CLEAR, 6 DESTINATION, 7 DESTINATION_OVER, 8 SOURCE_IN, 9 SOURCE_OUT, 10 SOURCE_ATOP, 11 DESTINATION_ATOP, 12 ADD, 13 MULTIPLY, 14 SCREEN, 15 OVERLAY, 16 DARKEN, 17 LIGHTEN, 18 DIFFERENCE, 19 EXCLUSION, 20 COLOR_DODGE, 21 COLOR_BURN, 22 HARD_LIGHT, 23 SOFT_LIGHT, 24 HUE, 25 SATURATION, 26 COLOR, 27 LUMINOSITY.
  • self (Self)

Returns:

Self

__eq__ 

fn def __eq__(self, other: Self) -> Bool

Args:

  • self (Self)
  • other (Self)

Returns:

Bool

__ne__ 

fn def __ne__(self, other: Self) -> Bool

Args:

  • self (Self)
  • other (Self)

Returns:

Bool

write_to 

fn def write_to[W: Writer](self, mut writer: W)

Parameters:

  • W (Writer)

Args:

  • self (Self)
  • writer (W)

__str__ 

fn def __str__(self) -> String

Args:

  • self (Self)

Returns:

String

is_source_over 

fn def is_source_over(self) -> Bool

Whether this is the default mode.

write_pixel and _fill_region ask this once per call before anything else, since it is what decides between the blend paths that were always there and the general one.

Args:

  • self (Self)

Returns:

Bool: True for SOURCE_OVER.

is_separable 

fn def is_separable(self) -> Bool

Whether this is one of the eleven separable blend modes, MULTIPLY through SOFT_LIGHT: a B applied to each channel on its own.

Args:

  • self (Self)

Returns:

Bool: True for the separable blend modes, False for the Porter-Duff operators and the non-separable modes.

is_non_separable 

fn def is_non_separable(self) -> Bool

Whether this is one of the four non-separable blend modes, HUE, SATURATION, COLOR and LUMINOSITY: a B that needs the whole RGB triple.

Args:

  • self (Self)

Returns:

Bool: True for the four non-separable modes.