Enum BlendMode 

#[repr(u32)]
pub enum BlendMode {
    Normal = 0,
    Multiply = 1,
    Screen = 2,
    Overlay = 3,
    SoftLight = 4,
    HardLight = 5,
    ColorDodge = 6,
    ColorBurn = 7,
    Difference = 8,
    Exclusion = 9,
    Add = 10,
    Subtract = 11,
    Darken = 12,
    Lighten = 13,
    Hue = 14,
    Saturation = 15,
    Color = 16,
    Luminosity = 17,
    And = 18,
    Average = 19,
    Bleach = 20,
    Divide = 21,
    Extremity = 22,
    Freeze = 23,
    Geometric = 24,
    Glow = 25,
    GrainExtract = 26,
    GrainMerge = 27,
    HardMix = 28,
    HardOverlay = 29,
    Harmonic = 30,
    Heat = 31,
    Interpolate = 32,
    LinearLight = 33,
    Multiply128 = 34,
    Negation = 35,
    Or = 36,
    Phoenix = 37,
    PinLight = 38,
    Reflect = 39,
    SoftDifference = 40,
    Stain = 41,
    VividLight = 42,
    Xor = 43,
}

Pixel-value blend modes.

The discriminant is the value written into the shader’s mode uniform, so variants are only ever appended, never renumbered. Each doc comment gives the normalised formula in terms of base and overlay (see the module docs for how those map onto FFmpeg’s A and B).

Variants

Normal = 0

Overlay replaces base.

Multiply = 1

base × overlay.

Screen = 2

1 − (1−base)(1−overlay).

Overlay = 3

Multiply below 50% grey, Screen above.

SoftLight = 4

base² + 2·overlay·base·(1−base).

HardLight = 5

Hard light — Overlay with base/overlay swapped.

ColorDodge = 6

base ≥ 1 ? base : min(1, overlay/(1−base)).

ColorBurn = 7

base ≤ 0 ? base : max(0, 1−(1−overlay)/base).

Difference = 8

|base − overlay|.

Exclusion = 9

base + overlay − 2·base·overlay.

Add = 10

clamp(base + overlay, 0, 1).

Subtract = 11

clamp(base − overlay, 0, 1).

Darken = 12

min(base, overlay).

Lighten = 13

max(base, overlay).

Hue = 14

Overlay hue + base saturation + base lightness.

Saturation = 15

Base hue + overlay saturation + base lightness.

Color = 16

Overlay hue + overlay saturation + base lightness.

Luminosity = 17

Base hue + base saturation + overlay lightness.

And = 18

Bitwise and of the two 8-bit samples.

Average = 19

(base + overlay)/2.

Bleach = 20

1 − base − overlay.

Divide = 21

overlay == 0 ? 1 : base/overlay.

Extremity = 22

|1 − base − overlay|.

Freeze = 23

overlay == 0 ? 0 : 1 − min((1−base)²/overlay, 1).

Geometric = 24

sqrt(max(base,0)·max(overlay,0)).

Glow = 25

base ≥ 1 ? base : min(1, overlay²/(1−base)).

GrainExtract = 26

0.5 + base − overlay (FFmpeg’s difference128).

GrainMerge = 27

base + overlay − 0.5 (FFmpeg’s addition128).

HardMix = 28

base < 1 − overlay ? 0 : 1.

HardOverlay = 29

base ≥ 1 ? 1 : min(1, base > 0.5 ? overlay/(2−2·base) : 2·base·overlay).

Harmonic = 30

base + overlay == 0 ? 0 : 2·base·overlay/(base + overlay).

Heat = 31

base == 0 ? 0 : 1 − min((1−overlay)²/base, 1).

Interpolate = 32

(2 − cos(base·π) − cos(overlay·π))/4.

LinearLight = 33

overlay + 2·base − 1.

The C branches on overlay < 0.5, but both arms collapse to the same expression once MAX == 2·HALF, which holds in the DEPTH == 32 branch. The 8-bit path differs by one LSB.

Multiply128 = 34

8·(base−0.5)·overlay + 0.5.

Negation = 35

1 − |1 − base − overlay|.

Or = 36

Bitwise or of the two 8-bit samples.

Phoenix = 37

min(base, overlay) − max(base, overlay) + 1.

PinLight = 38

overlay < 0.5 ? min(base, 2·overlay) : max(base, 2·overlay − 1).

Reflect = 39

overlay ≥ 1 ? overlay : min(1, base²/(1−overlay)).

SoftDifference = 40

base > overlay ? (overlay ≥ 1 ? 0 : (base−overlay)/(1−overlay)) : (overlay ≤ 0 ? 0 : (overlay−base)/overlay).

Stain = 41

2 − base − overlay.

VividLight = 42

base < 0.5 ? burn(2·base, overlay) : dodge(2·base − 1, overlay).

Xor = 43

Bitwise xor of the two 8-bit samples.

Trait Implementations

impl Clone for BlendMode

fn clone(&self) -> BlendMode

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for BlendMode

impl Debug for BlendMode

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for BlendMode

fn default() -> BlendMode

Returns the “default value” for a type.

impl Eq for BlendMode

impl PartialEq for BlendMode

fn eq(&self, other: &BlendMode) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for BlendMode