Safe Haskell | Safe-Inferred |
---|---|
Language | Haskell98 |
An RGBSpace
is characterized by Chromaticity
for red, green, and
blue, the Chromaticity
of the white point, and it's
TransferFunction
.
Synopsis
- data Colour a
- data RGB a = RGB {
- channelRed :: !a
- channelGreen :: !a
- channelBlue :: !a
- uncurryRGB :: (a -> a -> a -> b) -> RGB a -> b
- curryRGB :: (RGB a -> b) -> a -> a -> a -> b
- data RGBGamut
- mkRGBGamut :: RGB (Chromaticity Rational) -> Chromaticity Rational -> RGBGamut
- primaries :: RGBGamut -> RGB (Chromaticity Rational)
- whitePoint :: RGBGamut -> Chromaticity Rational
- inGamut :: (Ord a, Fractional a) => RGBGamut -> Colour a -> Bool
- data TransferFunction a = TransferFunction {
- transfer :: a -> a
- transferInverse :: a -> a
- transferGamma :: a
- linearTransferFunction :: Num a => TransferFunction a
- powerTransferFunction :: Floating a => a -> TransferFunction a
- inverseTransferFunction :: Fractional a => TransferFunction a -> TransferFunction a
- data RGBSpace a
- mkRGBSpace :: RGBGamut -> TransferFunction a -> RGBSpace a
- gamut :: RGBSpace a -> RGBGamut
- transferFunction :: RGBSpace a -> TransferFunction a
- linearRGBSpace :: Num a => RGBGamut -> RGBSpace a
- rgbUsingSpace :: Fractional a => RGBSpace a -> a -> a -> a -> Colour a
- toRGBUsingSpace :: Fractional a => RGBSpace a -> Colour a -> RGB a
Documentation
This type represents the human preception of colour.
The a
parameter is a numeric type used internally for the
representation.
The Monoid
instance allows one to add colours, but beware that adding
colours can take you out of gamut. Consider using blend
whenever
possible.
Instances
RGB Tuple
An RGB triple for an unspecified colour space.
RGB | |
|
uncurryRGB :: (a -> a -> a -> b) -> RGB a -> b Source #
Uncurries a function expecting three r, g, b parameters.
curryRGB :: (RGB a -> b) -> a -> a -> a -> b Source #
Curries a function expecting one RGB parameter.
RGB Gamut
An RGBGamut
is a 3-D colour “cube” that contains all the
colours that can be displayed by a RGB device.
The “cube” is normalized so that white has
luminance
1.
:: RGB (Chromaticity Rational) | The three primaries |
-> Chromaticity Rational | The white point |
-> RGBGamut |
An RGB gamut is specified by three primary colours (red, green, and
blue) and a white point (often d65
).
inGamut :: (Ord a, Fractional a) => RGBGamut -> Colour a -> Bool Source #
Returns True
if the given colour lies inside the given gamut.
RGB Space
data TransferFunction a Source #
A transfer
function is a function that typically translates linear
colour space coordinates into non-linear coordinates.
The transferInverse
function reverses this by translating non-linear
colour space coordinates into linear coordinates.
It is required that
transfer . transferInverse === id === transferInverse . inverse
(or that this law holds up to floating point rounding errors).
We also require that transfer
is approximately (**transferGamma)
(and hence transferInverse
is approximately
(**(recip transferGamma))
).
The value transferGamma
is for informational purposes only, so there
is no bound on how good this approximation needs to be.
TransferFunction | |
|
Instances
Num a => Semigroup (TransferFunction a) Source # | |
Defined in Data.Colour.RGBSpace (<>) :: TransferFunction a -> TransferFunction a -> TransferFunction a # sconcat :: NonEmpty (TransferFunction a) -> TransferFunction a # stimes :: Integral b => b -> TransferFunction a -> TransferFunction a # | |
Num a => Monoid (TransferFunction a) Source # | |
Defined in Data.Colour.RGBSpace mempty :: TransferFunction a # mappend :: TransferFunction a -> TransferFunction a -> TransferFunction a # mconcat :: [TransferFunction a] -> TransferFunction a # |
linearTransferFunction :: Num a => TransferFunction a Source #
This is the identity TransferFunction
.
powerTransferFunction :: Floating a => a -> TransferFunction a Source #
This is the (**gamma)
TransferFunction
.
inverseTransferFunction :: Fractional a => TransferFunction a -> TransferFunction a Source #
This reverses a TransferFunction
.
An RGBSpace
is a colour coordinate system for colours laying
inGamut
of gamut
.
Linear coordinates are passed through a transferFunction
to
produce non-linear RGB
values.
mkRGBSpace :: RGBGamut -> TransferFunction a -> RGBSpace a Source #
An RGBSpace is specified by an RGBGamut
and a TransferFunction
.
transferFunction :: RGBSpace a -> TransferFunction a Source #
linearRGBSpace :: Num a => RGBGamut -> RGBSpace a Source #
Produce a linear colour space from an RGBGamut
.
rgbUsingSpace :: Fractional a => RGBSpace a -> a -> a -> a -> Colour a Source #
toRGBUsingSpace :: Fractional a => RGBSpace a -> Colour a -> RGB a Source #