coloraide

0.13.0

• NEW: Add new closest method that takes a list of colors and returns the one that is closet to the calling color
  object.
• NEW: CSS color syntax no longer allows for forgiving channels in color(). This means that when a channel other
  than alpha is omitted, we will no longer treat them as undefined. Instead, the color will simply fail to parse.
  Raw data channels also must specify all channels.
• NEW: Clamp lower bounds of chroma at the channel level.
• NEW: coloraide.spaces.WHITES is now a 2 deep dictionary containing both 2˚ and 10˚ observer variants of white
  points.
• NEW: Color space plugins now specify WHITE as a tuple with the x and y chromaticity coordinates. This allows a
  space to specify unknown white points if desired.
• FIX: Fix longer hue interpolation when θ1 - θ2 = 0. The spec is wrong in this case, and interpolation should
  still occur the long way around instead of keeping hue constant.
• FIX: Reduce redundancy in some CSS parsing patterns.
• FIX: Minor performance improvements.
• FIX: Legacy rgb(), rgba(), hsl(), and hsla() comma separated forms in CSS do not support none, only the
  new space separated forms do.
• FIX: Ensure py.typed is installed with package so that type annotations work properly.

0.12.0

• NEW: Add a gamut mapping variant that matches the CSS Color Level 4 spec.
• FIX: Fix precision rounding issue.

0.11.0

Warning: Breaking Changes

1. Prior to 0.11.0, if you specified a cylindrical space directly, ColorAide would normalize undefined hues the same
   way that the conversion algorithm did. In the below case, saturation is zero, so the hue was declared undefined.

   >>> Color('hsl(270 0% 50%)')
   color(--hsl none 0 0.5 / 1)
   

   We should not have been doing this, and it made some cases of interpolation a bit confusing. It is no longer
   done as the hues are in fact specified by the user, even if they are powerless in relation to contributing to
   the rendered color. When a cylindrical color is converted or if a user declares the channel as undefined with
   none or some other way, then the channel will be declared undefined, because in these cases, they truly are.

   >>> Color('white').convert('hsl')
   color(--hsl none 0 1 / 1)
   >>> Color('color(--hsl none 0 0.5)')
   color(--hsl none 0 0.5)
   

   If you are working directly in a cylindrical color space and ever wish to force the normalization of color hues
   as undefined when the color meets the usual requirements as specified by the color space's current rules, just
   call normalize on the color and it will apply the same logic that occurs during the conversion process.

   >>> Color('hsl(270 0% 50%)').normalize()
   color(--hsl none 0 0.5 / 1)
   

2. If you relied on commas in CSS forms that did not support them, this behavior is no longer allowed. It was
   thought that CSS may consider allowing comma formats in formats like hwb(), etc., and it was considered, but
   ultimately the decision was to avoid adding such support. We've updated our input and output support to reflect
   this. Color spaces can always be subclassed and have this support added back, if desired, but will not be shipped
   as the default anymore.

3. The D65 form of Luv and LCHuv is now the only supported Luv based color spaces by default now. D50 Luv and LCHuv
   have been dropped and luv and lchuv now refers to the D65 version. In most places, the D65 is the most common
   used white space as most monitors are calibrated for this white point. The only reason CIELAB and CIELCH are D50
   by default is that CSS requires it. Anyone interested in using Luv with a different white point can easily
   subclass the current Luv and create a new plugin color space that uses the new white point.

4. Renamed DIN99o Lch identifier to the short name of lch99o.>

• NEW: ColorAide now only ships with the D65 version Luv and LCHuv as D65, in most places is the expected white
  space. Now, the identifier luv and lchuv will refer to the D65 version of the respective color spaces. D50
  variants are no longer available by default.
• NEW: Add the HSLuv color space.
• NEW: DIN99o Lch identifier was renamed from din99o-lch to lch99o. To use in CSS color() form, use
  --lch99o.
• NEW: Refactor chroma reduction/MINDE logic to cut processing time in half. Gamut mapping results remain very
  similar.
• NEW: Be more strict with CSS inputs and outputs. hwb(), lab(), lch(), oklab(), and oklch() no longer
  support comma string formats.
• NEW: Officially drop Python 3.6 support.
• FIX: Do not assume user defined, powerless hues as undefined. If they are defined by the user, they should be
  respected, even if they have no effect on the current color. This helps to ensure interpolations acts in an
  unsurprising way. If a user manually specifies the channel with none, then it will be considered undefined, or if
  the color goes through a conversion to a space that cannot pick an appropriate hue, they will also be undefined.

0.10.0

• NEW: Switch back to using CIELCH for gamut mapping (lch-chroma). There are still some edge cases that make
  oklch-chroma less desirable.
• FIX: Fix an issue where when attempting to generate steps some ∆E distance apart, the maximum step range was not
  respected and could result in large hangs.

0.9.0

Warning: Breaking Change
Custom gamut mapping plugins no longer return coordinates and require the method to update the passed in color.

• NEW: Improved, faster gamut mapping algorithm.
• NEW: FIT plugins (gamut mapping) no longer return coordinates but should modify the color passed in.
• NEW: Expose default interpolation space as a class variable that can be controlled when creating a custom class
  via class inheritance.
• NEW: Colors can now directly specify the ∆E method that is used when interpolating color steps and using
  max_delta_e via the new delta_e argument. If the delta_e parameter is omitted, the color object's default ∆E
  method will be used.
• NEW: Oklab is now the default interpolation color space.
• NEW: Interpolation will now avoid fitting colors that are out of gamut unless the color space cannot represent
  out of gamut colors. Currently, all of the RGB colors (srgb, display-p3, etc.) all support extended ranges, but
  the HSL, HWB, and HSV color models for srgb (including spaces such as okhsl and okhsv) do not support extended
  ranges and will still be gamut mapped.
• FIX: Remove some incorrect code from the gamut mapping algorithm that would shortcut the mapping to reduce chroma
  to zero.

0.8.0

Warning: Breaking Change

The use of xyz as the color space name has been changed in favor of xyz-d65. This better matches the CSS
specification. As we are still in a prerelease state, we have not provided any backwards compatibility.

CSS color input strings in the form #!css-color color(xyz x y z) will continue to be accepted as CSS will allow
both the xyz and the xyz-d65 identifier, but output serialization will prefer the
#!css-color color(xyz-d65 x y z) form as using xyz is an alias for xyz-d65.

Again, this breaking change only affects operations where the color space "name" is used in the API to specify usage
of a specific color space in order to create a color, convert, mutate, interpolate, etc.

Color('red').convert('xyz')      # Bad
Color('red').convert('xyz-d65')  # Okay

Color('xyz' [0, 0, 0])      # Bad
Color('xyz-d65' [0, 0, 0])  # Okay

Color('red').interpolate('green', space='xyz')      # Bad
Color('red').interpolate('green', space='xyz-d65')  # Okay

# No changes to CSS inputs
Color('color(xyz 0 0 0)')      # Okay
Color('color(xyz-d65 0 0 0)')  # Okay

• NEW: Custom fit plugin's fit method now allows additional kwargs in its signature. The API will accept
  kwargs allowing a custom fit plugin to have configurable parameters. None of the current built-in plugins provide
  additional parameters, but this is provided in case it is found useful in the future.
• NEW: XYZ D65 space will now be known as xyz-d65, not xyz. Per the CSS specification, we also ensure XYZ D65
  color space serializes as xyz-d65 instead of the alias xyz. CSS input string format will still accept the xyz
  identifier as this is defined in the CSS specification as an alias for xyz-d65, but when serializing a color to a
  string, the xyz-d65 will be used as the preferred form.
• NEW: By default, gamut mapping is done with oklch-chroma which matches the current CSS specification. If
  desired, the old way (lch-chroma) can manually be specified or set as the default by subclassing Color and setting
  FIT to lch-chroma.
• FIX: Ensure the convert method's fit parameter is typed appropriately and is documented correctly.

0.7.0

• NEW: Formally expose srgb-linear as a valid color space.
• NEW: Distance plugins and gamut mapping plugins now use classmethod instead of staticmethod. This allows for
  inheritance from other classes and the overriding of plugin options included as class members.
• NEW: Tweak Lch chroma gamut mapping threshold.
• FIX: Issue where it is possible, when generating steps, to cause a shift in midpoint of colors if exceeding the
  maximum steps. Ensure that no stops are injected if injecting a stop between every color would exceed the max steps.

0.6.0

• NEW: Update spaces such that they provide a single conversion point which simplifies color space API and
  centralizes all conversion logic allowing us to pull chromatic adaptation out of spaces.
• NEW: color() output format never uses percent when serializing, but will optionally accept percent as input.
• NEW: Slight refactor of color space, delta E, and gamut mapping plugins. All now specify there name via the
  property NAME instead of methods space() for color spaces and name() for other plugins.
• NEW: Restructure source structure by flattening out some directories and better organizing source files. This
  changes some import paths.
• NEW: Color spaces do not specify alpha in CHANNEL_NAMES as the alpha name cannot be changed.
• NEW: Color space objects do not need a constant to track number of color channels.

0.5.0

• NEW: Add type annotations and refactor code to better accommodate the type annotations. Public API not really
  affected, but a bit of the internals have changed.
• FIX: Fix issue where compose, if backdrop list is empty, would not respect in_place option.

0.4.0

• NEW: Officially support Python 3.10.
• NEW: Slightly more accurate Oklab matrix calculation.
• NEW: Exported dictionary form can now be used as a normal color input in functions like contrast, interpolate,
  etc.
• NEW: Color objects will accept a dictionary mapping when alpha is not specified. When this occurs, alpha is
  assumed to be 1.
• FIX: Fix an object compare issue.

0.3.0

Breaking Change
XYZ changes below will cause breakage as xyz now refers to XYZ with D65 instead of D50. Also, CSS identifiers
changed per the recent specification change.

• NEW: When calling dir() on Color(), ensure dynamic methods are in the list.
• NEW: xyz now refers to XYZ D65. CSS color() function now specifies D65 color as either
  color(xyz x y z) or color(xyz-d65 x y z). XYZ D50 is now specified as
  color(xyz-D50 x y z).
• NEW: Add CIELUV and CIELCHuv D65 variants.

0.2.0

• NEW: Provide dedicated clip method. clip is still a specifiable method under the fit function. It is also a reserved name under fit and cannot be overridden via plugins or be removed.
• NEW: Add more conversion shortcuts to OK family of color spaces.
• FIX: Fix an issue where the shorter conversion path wasn't always taken as convert couldn't find to/from methods if the color space name had - in it.

0.1.0

First non-alpha prerelease. Notable changes from the last alpha listed below.

Breaking Changes:
There are some breaking changes if coming from the previous alpha releases. All sRGB cylindrical spaces' non-hue
data ranges are no longer scaled to 0 - 100, but use 0 - 1. Hue ranges have not changed.

• NEW: By accepting HSL, HSV, and HWB as non-hue channels as 0-100, we do lose a little precision, so for 1.0, we
  are switching to accepting and returning raw data values between 0 - 1. We've kept hue between 0 - 360 as it is easier
  for users to deal with hues between 0 - 360. Doing this will also match the new color spaces Okhsl and Okhsv that
  need to be kept at 0 - 1 to get better rounding.
• NEW: We do not currently restrict percentages anymore in #!css-color color() functions. There is no hard rules
  that we need to at this time and no currently specified spaces that do this in the CSS specification. This is relaxed
  for now until some future time when it becomes clear we must.
• NEW: New okhsl and okhsv color space.
• NEW: All color channels now accept the none keyword to specify an undefined channel. They can also optionally
  output CSS strings with the keyword.
• NEW: Interpolation will return an undefined channel if both colors have that channel set to undefined.
• NEW: Provide a way to dump a color object to a simple dictionary and have the Color() object accept that
  dictionary to recreate the color object.
• NEW: Provide cat16 chromatic adaptation.
• NEW: Add normalize method to force channel normalization (evaluation of channels and setting undefined as
  appropriate).
• NEW: Interpolated and composited colors will normalize undefined channels when returning a color.
• NEW: Jzazbz now also has an alias for az and bz channels as a and b respectively.
• FIX: Fix an attribute "get" issue where attributes that were not present on the Color() object appeared to be
  present when using hasattr().
• FIX: More accurate Oklab matrix.

0.1.0a27

• NEW: Add new register and deregister method to allow adding new spaces, Delta E methods, or gamut mapping
  methods.
• NEW: Rework Delta E and gamut mapping methods as static plugin classes.
• NEW: When Color() class is subclassed, ensure the subclass is using copies of the base class plugin mappings.
  This is done with a special metaclass. This will prevent accidental appending and deleting of plugins on a subclass
  that affects the base class.
• NEW: Add new API for getting uv and xy values.
• NEW: Add new API for getting the white point (as an XYZ value) for a specific color.
• NEW: Channel values are generally more terse for easy typing, but many channels that map to a more verbose name
  (think l and lightness) will still recognize the more verbose alias. Others that didn't specifically use the
  more verbose name (think jz which is also lightness) now have a more verbose alias.

0.1.0a26

• NEW: Use D65 and D50 white points as specified in CSS spec, but limited to 4 decimals as everyone else seems to
  do. Other white points were also adjusted as outlined in CIE 2004 Colorimetry T.3 and T.8.
• FIX: When converting, ensure that NaNs are converted to normal numbers.

0.1.0a25

• NEW: Add luv and lchuv color space using a D50 illuminant.
• NEW: Add din99o and din99o-lch color space using a D65 illuminant and associated Delta E99o distance
  algorithm.
• NEW: Make it easier to add additional Delta E methods and gamut mapping methods to a custom Color() class.
• NEW: Add new Delta Ez algorithm (Jzazbz).
• NEW: Add new Delta Ehyab algorithm for any Lab-ish style color spaces.
• NEW: Expose delta_e_<type> methods dynamically depending on what Delta E methods are currently available.
• FIX: Consistent calculation of achromatic thresholds across all Lch-ish color spaces.

0.1.0a24

• NEW: color() function locks accepted to channels to the number of actual channels.
• NEW: All color() function implementations for color spaces that do not formally support such notation in the
  current CSS spec now use the custom identifier notation --name. For instance, HSL, which does not support the
  color() format in the CSS spec, is now specified via: color(--hsl h s l / a).
• NEW: Channels that do not support percentages will no longer be accepted in the color() form. For instance,
  according to the CSS spec, XYZ color space does not allow percentages in the color() format. ColorAide will no
  longer allow such notation in order to conform to the spec. color(--lab) will still support percentages for l as
  it did prior to removal from the spec. All other percentage only channels will also still be supported.
• NEW: Internal restructuring of some files and file locations.

0.1.0a23

• FIX: Faster precision adjustment.

0.1.0a22

• FIX: Don't have sRGB fail gamut check due to HSL having extreme numbers. If sRGB is within tolerance range, it
  should pass. Instead, HSL, HSV, and HWB will all be checked to see if they are within the sRGB gamut as they are just
  representations of sRGB, but they will also have the tolerance checked against their own coordinates to help catch
  values that are way out of bounds but still yield values within the sRGB tolerance range.
• FIX: Improve gamut mapping a bit more.

0.1.0a21

• NEW: Refactor CAT to allow for other CAT methods: von-kries, xyz-scaling, cat02, cmccat97, cmccat2000,
  and sharp. Currently, bradford is the default and the overall preferred option.
• FIX: Fix issues gamut mapping algorithm.