Blend Modes

BlendNormal

The destination color is always the source color.

    Cdest = Csrc

BlendMultiply

The source color is multiplied by the backdrop color.

    Cdest = Cb × Csrc

BlendScreen

The complementary colors of the source and backdrop colors are multiplied, and the destination color is the complementary color of the multiplicated color.

    Cdest = 1 - ((1 - Cb) × (1 - Csrc))

BlendOverlay

This mode uses the multiply or screen mode, depending on the backdrop color. The overlay mode is the inverse of the hard-light mode.

    if Cb <= 0.5
        Cdest = Csrc × 2Cb
    else
        Cdest = 1 - ((1 - Csrc) × (1 - 2Cb))
    end

BlendDarken

The darker values of the backdrop color and the source color are selected.

    Cdest = min(Cb, Csrc)

BlendLighten

The lighter values of the backdrop color and the source color are selected.

    Cdest = max(Cb, Csrc)

BlendColorDodge

The destination color is the result of dividing the backdrop color by the complementary color of the source color.

    if Cb == 0
        Cdest = 0
    elseif Csrc == 1
        Cdest = 1
    else
        Cdest = min(1, Cb / (1 - Csrc))
    end

BlendColorBurn

The destination color is the result of dividing the complementary color of the backdrop color by the source color.

ColorBlendModes uses the definition of W3C drafts as shown below. Note that there is a variant, which returns 0 when Cb == 1 and Csrc == 0.

    if Cb == 1
        Cdest = 1
    elseif Csrc == 0
        Cdest = 0
    else
        Cdest = 1 - min(1, (1 - Cb) / Csrc)
    end

BlendHardLight

This mode uses the multiply or screen mode, depending on the source color. The overlay mode is the inverse of the overlay mode.

    if Csrc <= 0.5
        Cdest = Cb × 2Csrc
    else
        Cdest = 1 - ((1 - Cb) × (1 - 2Csrc))
    end

BlendSoftLight

The result is similar to the hard-light mode, but milder. This mode is also related to the overlay mode.

ColorBlendModes uses the definition of W3C drafts as shown below. Note that there are different definitions of the soft-light.

    if Csrc <= 0.5
        Cdest = Cb - (1 - 2Csrc) × Cb × (1 - Cb)
    else
        if Cb <= 0.25
            D = ((4Cb - 3) × Cb + 1) × 4Cb
        else
            D = sqrt(Cb)
        end
        Cdest = Cb + (2Csrc - 1) × (D - Cb)
    end

BlendDifference

The destination values are the subtraction of the darker values from the lighter values of the backdrop and source colors.

    Cdest = abs(Csrc - Cb)

BlendExclusion

The result is similar to the difference mode, but milder.

    Cdest = Cb + Csrc - 2Cb × Csrc

BlendHue

The result is a color with the hue of the source color and the saturation and luminosity of the backdrop color.

BlendSaturation

The result is a color with the saturation of the source color and the hue and luminosity of the backdrop color.

BlendColor

The result is a color with the hue and saturation of the source color and the luminosity of the backdrop color.

BlendLuminosity

The result is a color with the luminosity of the source color and the hue and saturation of the backdrop color.