colorspace

var (
	// AdaptationBradford is the Bradford chromatic adaptation transform, as defined in the CIECAM97s color appearance model.
	AdaptationBradford = Adaptation{
		Transform: []float32{
			0.8951, -0.7502, 0.0389,
			0.2664, 1.7135, -0.0685,
			-0.1614, 0.0367, 1.0296,
		},
	}

	// AdaptationVonKries is the von Kries chromatic adaptation transform.
	AdaptationVonKries = Adaptation{
		Transform: []float32{
			0.40024, -0.22630, 0.00000,
			0.70760, 1.16532, 0.00000,
			-0.08081, 0.04570, 0.91822,
		},
	}

	// AdaptationCiecat02 is the CIECAT02 chromatic adaption transform, as defined in the CIECAM02 color appearance model.
	AdaptationCiecat02 = Adaptation{
		Transform: []float32{
			0.7328, -0.7036, 0.0030,
			0.4296, 1.6975, 0.0136,
			-0.1624, 0.0061, 0.9834,
		},
	}
)

var (
	// Rgb is a color model with 3 components that refer to the three additive
	// primaries: red, green and blue.
	ColorModelRgb = ColorModel{util.PackInts(3, 0)}

	// Xyz is a color model with 3 components that are used to model human color
	// vision on a basic sensory level.
	ColorModelXyz = ColorModel{util.PackInts(3, 1)}

	// Lab is a color model with 3 components used to describe a color space that is
	// more perceptually uniform than XYZ.
	ColorModelLab = ColorModel{util.PackInts(3, 2)}

	// Cmyk is a color model with 4 components that refer to four inks used in color
	// printing: cyan, magenta, yellow and black (or key). CMYK is a subtractive color model.
	ColorModelCmyk = ColorModel{util.PackInts(4, 3)}
)

var (
	// SrgbTransferParameters for sRGB.
	// gamma=2.4, a=1/1.055, b=0.055/1.055, c=1/12.92, d=0.04045
	SrgbTransferParameters = &TransferParameters{
		Gamma: 2.4,
		A:     1.0 / 1.055,
		B:     0.055 / 1.055,
		C:     1.0 / 12.92,
		D:     0.04045,
		E:     0.0,
		F:     0.0,
	}

	SrgbPrimaries = []float32{0.640, 0.330, 0.300, 0.600, 0.150, 0.060}

	SrgbTransform = []float32{
		0.412391, 0.357584, 0.180481,
		0.212639, 0.715169, 0.072192,
		0.019331, 0.119195, 0.950532,
	}

	Srgb = NewRgb(
		"sRGB IEC61966-2.1",
		SrgbPrimaries,
		IlluminantD65,
		SrgbTransform,
		func(x float64) float64 {
			return RcpResponse(x, SrgbTransferParameters.A, SrgbTransferParameters.B, SrgbTransferParameters.C, SrgbTransferParameters.D, SrgbTransferParameters.Gamma)
		},
		func(x float64) float64 {
			return Response(x, SrgbTransferParameters.A, SrgbTransferParameters.B, SrgbTransferParameters.C, SrgbTransferParameters.D, SrgbTransferParameters.Gamma)
		},
		0.0, 1.0,
		SrgbTransferParameters,
		ColorSpaceSrgb,
	)

	LinearSrgb = NewRgb(
		"sRGB IEC61966-2.1 (Linear)",
		SrgbPrimaries,
		IlluminantD65,
		SrgbTransform,
		func(x float64) float64 { return x },
		func(x float64) float64 { return x },
		0.0, 1.0,
		&TransferParameters{Gamma: 1.0, A: 1.0, B: 0.0, C: 0.0, D: 0.0, E: 0.0, F: 0.0},
		ColorSpaceLinearSrgb,
	)

	// Extended sRGB (scRGB)
	ExtendedSrgb = NewRgb(
		"scRGB-nl IEC 61966-2-2:2003",
		SrgbPrimaries,
		IlluminantD65,
		SrgbTransform,
		func(x float64) float64 {
			return RcpResponseExtended(x, SrgbTransferParameters.A, SrgbTransferParameters.B, SrgbTransferParameters.C, SrgbTransferParameters.D, SrgbTransferParameters.E, SrgbTransferParameters.F, SrgbTransferParameters.Gamma)
		},
		func(x float64) float64 {
			return ResponseExtended(x, SrgbTransferParameters.A, SrgbTransferParameters.B, SrgbTransferParameters.C, SrgbTransferParameters.D, SrgbTransferParameters.E, SrgbTransferParameters.F, SrgbTransferParameters.Gamma)
		},
		-0.799, 2.399,
		SrgbTransferParameters,
		ColorSpaceExtendedSrgb,
	)

	// Linear Extended sRGB
	LinearExtendedSrgb = NewRgb(
		"scRGB IEC 61966-2-2:2003",
		SrgbPrimaries,
		IlluminantD65,
		SrgbTransform,
		func(x float64) float64 { return x },
		func(x float64) float64 { return x },
		-0.5, 7.499,
		&TransferParameters{Gamma: 1.0, A: 1.0, B: 0.0, C: 0.0, D: 0.0, E: 0.0, F: 0.0},
		ColorSpaceLinearExtendedSrgb,
	)

	DisplayP3 = NewRgb(
		"Display P3",
		[]float32{0.680, 0.320, 0.265, 0.690, 0.150, 0.060},
		IlluminantD65,
		[]float32{
			0.486570948965, 0.265667693169, 0.198217285234,
			0.228974564069, 0.691738521836, 0.079286914094,
			0.000000000000, 0.045113381846, 1.043944368900,
		},
		Srgb.Oetf,
		Srgb.Eotf,
		0.0, 1.0,
		SrgbTransferParameters,
		ColorSpaceDisplayP3,
	)

	// Oklab instance
	OklabInstance = NewOklab("Oklab", ColorSpaceOklab)

	Unspecified = &unspecifiedColorSpace{
		BaseColorSpace: NewBaseColorSpace("Unspecified", ColorModelRgb, MinId),
	}
)

var (
	// IlluminantA is Standard CIE 1931 2° illuminant A, encoded in xyY. This illuminant has a color temperature of 2856K.
	IlluminantA = NewWhitePoint(0.44757, 0.40745)

	// IlluminantB is Standard CIE 1931 2° illuminant B, encoded in xyY. This illuminant has a color temperature of 4874K.
	IlluminantB = NewWhitePoint(0.34842, 0.35161)

	// IlluminantC is Standard CIE 1931 2° illuminant C, encoded in xyY. This illuminant has a color temperature of 6774K.
	IlluminantC = NewWhitePoint(0.31006, 0.31616)

	// IlluminantD50 is Standard CIE 1931 2° illuminant D50, encoded in xyY. This illuminant has a color temperature of 5003K.
	IlluminantD50 = NewWhitePoint(0.34567, 0.35850)

	// IlluminantD55 is Standard CIE 1931 2° illuminant D55, encoded in xyY. This illuminant has a color temperature of 5503K.
	IlluminantD55 = NewWhitePoint(0.33242, 0.34743)

	// IlluminantD60 is Standard CIE 1931 2° illuminant D60, encoded in xyY. This illuminant has a color temperature of 6004K.
	IlluminantD60 = NewWhitePoint(0.32168, 0.33767)

	// IlluminantD65 is Standard CIE 1931 2° illuminant D65, encoded in xyY. This illuminant has a color temperature of 6504K.
	IlluminantD65 = NewWhitePoint(0.31271, 0.32902)

	// IlluminantD75 is Standard CIE 1931 2° illuminant D75, encoded in xyY. This illuminant has a color temperature of 7504K.
	IlluminantD75 = NewWhitePoint(0.29902, 0.31485)

	// IlluminantE is Standard CIE 1931 2° illuminant E, encoded in xyY. This illuminant has a color temperature of 5454K.
	IlluminantE = NewWhitePoint(0.33333, 0.33333)

	// IlluminantD50Xyz is the XYZ representation of D50.
	IlluminantD50Xyz = []float32{0.964212, 1.0, 0.825188}
)

var (
	// Matrices for M1 and M2 in Oklab spec
	M1 = []float32{
		0.8189330101, 0.3618667424, -0.1288597137,
		0.0329845436, 0.9293118715, 0.0361456387,
		0.0482003018, 0.2643662691, 0.6338517070,
	}
	M2 = []float32{
		0.2104542553, 1.9779984951, 0.0259040371,
		0.7936177850, -2.4285922050, 0.7827717662,
		-0.0040720468, 0.4505937, -0.8086757660,
	}
	InverseM1 = util.Inverse3x3(M1)
	InverseM2 = util.Inverse3x3(M2)
)