Type Alias rsvg::surface_utils::Pixel

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pub type Pixel = RGBA8;

Expand description

A pixel consisting of R, G, B and A values.

Aliased Type§

struct Pixel {
    pub r: u8,
    pub g: u8,
    pub b: u8,
    pub a: u8,
}

Fields§

§r: u8

Red

§g: u8

Green

§b: u8

Blue

§a: u8

Alpha

Trait Implementations§

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impl PixelOps for Pixel

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fn unpremultiply(self) -> Self

Returns an unpremultiplied value of this pixel.

For a fully transparent pixel, a transparent black pixel will be returned.

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fn premultiply(self) -> Self

Returns a premultiplied value of this pixel.

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fn to_luminance_mask(&self) -> Self

Returns a ‘mask’ pixel with only the alpha channel

Assuming, the pixel is linear RGB (not sRGB) y = luminance Y = 0.2126 R + 0.7152 G + 0.0722 B 1.0 opacity = 255

When Y = 1.0, pixel for mask should be 0xFFFFFFFF (you get 1.0 luminance from 255 from R, G and B)

r_mult = 0xFFFFFFFF / (255.0 * 255.0) * .2126 = 14042.45 ~= 14042 g_mult = 0xFFFFFFFF / (255.0 * 255.0) * .7152 = 47239.69 ~= 47240 b_mult = 0xFFFFFFFF / (255.0 * 255.0) * .0722 = 4768.88 ~= 4769

This allows for the following expected behaviour: (we only care about the most significant byte) if pixel = 0x00FFFFFF, pixel’ = 0xFF…… if pixel = 0x00020202, pixel’ = 0x02…… if pixel = 0x00000000, pixel’ = 0x00……

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