/* See LICENSE file for copyright and license details. */

#define MARSHAL_VERSION 1


TYPE libcolour_srgb_encode(TYPE t) { return srgb_encode(t); }
TYPE libcolour_srgb_decode(TYPE t) { return srgb_decode(t); }


int
libcolour_convert(const libcolour_colour_t *from, libcolour_colour_t *to)
{
	return libcolour_convert_en_masse(from, to,
					  LIBCOLOUR_CONVERT_EN_MASSE_SEPARATED |
					  LIBCOLOUR_CONVERT_EN_MASSE_ON_CPU |
					  LIBCOLOUR_CONVERT_EN_MASSE_NO_OVERRIDE, 1,
					  &from->srgb.R, &from->srgb.G, &from->srgb.B,
					  &to->srgb.R, &to->srgb.G, &to->srgb.B);
}


int
libcolour_delta_e(const libcolour_colour_t *a, const libcolour_colour_t *b, TYPE *e)
{
	libcolour_cielab_t u, v;
	u.model = v.model = LIBCOLOUR_CIELAB;
	if (libcolour_convert(a, (libcolour_colour_t *)&u))
		return -1;
	if (libcolour_convert(b, (libcolour_colour_t *)&v))
		return -1;
	u.L -= v.L, u.L *= u.L;
	u.a -= v.a, u.a *= u.a;
	u.b -= v.b, u.b *= u.b;
	*e = xsqrt(u.L + u.a + u.b);
	return 0;
}


#define eliminate(M, n, m) eliminate_(n, m, &(M))
static int
eliminate_(size_t n, size_t m, TYPE (*Mp)[n][m])
{
#define M (*Mp)
	size_t r1, r2, c;
	TYPE d;
	TYPE *R1;
	TYPE *R2;
	for (r1 = 0; r1 < n; r1++) {
		R1 = M[r1];
		if (R1[r1] == 0) {
			for (r2 = r1 + 1; r2 < n; r2++)
				if (M[r2][r1] != 0)
					break;
			if (r2 == n) {
				errno = EDOM;
				return -1;
			}
			R2 = M[r2];
			for (c = 0; c < m; c++)
				d = R1[c], R1[c] = R2[c], R2[c] = d;
		}
		d = R1[r1];
		for (c = 0; c < m; c++)
			R1[c] /= d;
		for (r2 = r1 + 1; r2 < n; r2++) {
			R2 = M[r2];
			d = R2[r1];
			for (c = 0; c < m; c++)
				R2[c] -= R1[c] * d;
		}
	}
	for (r1 = n; --r1;) {
		R1 = M[r1];
		for (r2 = r1; r2--;) {
			R2 = M[r2];
			d = R2[r1];
			for (c = 0; c < m; c++)
				R2[c] -= R1[c] * d;
		}
	}
	return 0;
#undef M
}


int
libcolour_proper(libcolour_colour_t *colour)
{
	libcolour_colour_t r, g, b, w;
	TYPE m[3][4];
	switch (colour->model) {
	case LIBCOLOUR_CIELUV:
		colour->cieluv.white.model = LIBCOLOUR_CIEXYZ;
		break;
	case LIBCOLOUR_CIELCHUV:
		colour->cielchuv.white.model = LIBCOLOUR_CIEXYZ;
		if (!colour->cielchuv.one_revolution)
			colour->cielchuv.one_revolution = D(360.);
		break;
	case LIBCOLOUR_RGB:
		colour->rgb.red.model   = LIBCOLOUR_CIEXYY;
		colour->rgb.green.model = LIBCOLOUR_CIEXYY;
		colour->rgb.blue.model  = LIBCOLOUR_CIEXYY;
		colour->rgb.white.model = LIBCOLOUR_CIEXYY;
		colour->rgb.red.Y   = 1;
		colour->rgb.green.Y = 1;
		colour->rgb.blue.Y  = 1;
		r.model = g.model = b.model = w.model = LIBCOLOUR_CIEXYZ;
		libcolour_convert((const libcolour_colour_t *)&colour->rgb.red, &r);
		libcolour_convert((const libcolour_colour_t *)&colour->rgb.green, &g);
		libcolour_convert((const libcolour_colour_t *)&colour->rgb.blue, &b);
		libcolour_convert((const libcolour_colour_t *)&colour->rgb.white, &w);
		m[0][0] = r.ciexyz.X, m[0][1] = g.ciexyz.X, m[0][2] = b.ciexyz.X, m[0][3] = w.ciexyz.X;
		m[1][0] = r.ciexyz.Y, m[1][1] = g.ciexyz.Y, m[1][2] = b.ciexyz.Y, m[1][3] = w.ciexyz.Y;
		m[2][0] = r.ciexyz.Z, m[2][1] = g.ciexyz.Z, m[2][2] = b.ciexyz.Z, m[2][3] = w.ciexyz.Z;
		if (eliminate(m, 3, 4))
			return -1;
		colour->rgb.red.Y   = m[0][3];
		colour->rgb.green.Y = m[1][3];
		colour->rgb.blue.Y  = m[2][3];
		break;
	default:
		break;
	}
	return 0;
}


static int
get_primaries(libcolour_rgb_t *cs)
{
	libcolour_colour_t r, g, b, w;
	TYPE Sr, Sg, Sb;

	r.model = g.model = b.model = w.model = LIBCOLOUR_CIEXYZ;
	r.ciexyz.Y = 1;
	g.ciexyz.Y = 1;
	b.ciexyz.Y = 1;

	Sr = cs->M[1][0] * cs->white_r;
	Sg = cs->M[1][1] * cs->white_g;
	Sb = cs->M[1][2] * cs->white_b;

	r.ciexyz.X = cs->M[0][0] / Sr, r.ciexyz.Z = cs->M[2][0] / Sr;
	g.ciexyz.X = cs->M[0][1] / Sg, g.ciexyz.Z = cs->M[2][1] / Sg;
	b.ciexyz.X = cs->M[0][2] / Sb, b.ciexyz.Z = cs->M[2][2] / Sb;

	w.ciexyz.X = Sr;
	w.ciexyz.Y = Sg;
	w.ciexyz.Z = Sb;

	cs->red.model   = LIBCOLOUR_CIEXYY;
	cs->green.model = LIBCOLOUR_CIEXYY;
	cs->blue.model  = LIBCOLOUR_CIEXYY;
	cs->white.model = LIBCOLOUR_CIEXYY;

	libcolour_convert(&r, (libcolour_colour_t *)&cs->red);
	libcolour_convert(&g, (libcolour_colour_t *)&cs->green);
	libcolour_convert(&b, (libcolour_colour_t *)&cs->blue);
	libcolour_convert(&w, (libcolour_colour_t *)&cs->white);

	return 0;
}


static int
get_matrices(libcolour_rgb_t *cs)
{
	libcolour_colour_t r, g, b, w;
	TYPE M[3][6];
	TYPE Sr, Sg, Sb;

	r.model = g.model = b.model = LIBCOLOUR_CIEXYZ;
	w.model = LIBCOLOUR_CIEXYY;
	libcolour_convert((const libcolour_colour_t *)&cs->red,   &w), w.ciexyy.Y = 1, libcolour_convert(&w, &r);
	libcolour_convert((const libcolour_colour_t *)&cs->green, &w), w.ciexyy.Y = 1, libcolour_convert(&w, &g);
	libcolour_convert((const libcolour_colour_t *)&cs->blue,  &w), w.ciexyy.Y = 1, libcolour_convert(&w, &b);
	w.model = LIBCOLOUR_CIEXYZ;
	libcolour_convert((const libcolour_colour_t *)&cs->white, &w);

	M[0][0] = r.ciexyz.X, M[0][1] = g.ciexyz.X, M[0][2] = b.ciexyz.X, M[0][3] = 1, M[0][4] = 0, M[0][5] = 0;
	M[1][0] = r.ciexyz.Y, M[1][1] = g.ciexyz.Y, M[1][2] = b.ciexyz.Y, M[1][3] = 0, M[1][4] = 1, M[1][5] = 0;
	M[2][0] = r.ciexyz.Z, M[2][1] = g.ciexyz.Z, M[2][2] = b.ciexyz.Z, M[2][3] = 0, M[2][4] = 0, M[2][5] = 1;

	if (eliminate(M, 3, 6))
		return -1;

	Sr = M[0][3] * w.ciexyz.X + M[0][4] * w.ciexyz.Y + M[0][5] * w.ciexyz.Z;
	Sg = M[1][3] * w.ciexyz.X + M[1][4] * w.ciexyz.Y + M[1][5] * w.ciexyz.Z;
	Sb = M[2][3] * w.ciexyz.X + M[2][4] * w.ciexyz.Y + M[2][5] * w.ciexyz.Z;

	Sr /= cs->white_r;
	Sg /= cs->white_g;
	Sb /= cs->white_b;

	cs->M[0][0] = Sr * r.ciexyz.X, cs->M[0][1] = Sg * g.ciexyz.X, cs->M[0][2] = Sb * b.ciexyz.X;
	cs->M[1][0] = Sr * r.ciexyz.Y, cs->M[1][1] = Sg * g.ciexyz.Y, cs->M[1][2] = Sb * b.ciexyz.Y;
	cs->M[2][0] = Sr * r.ciexyz.Z, cs->M[2][1] = Sg * g.ciexyz.Z, cs->M[2][2] = Sb * b.ciexyz.Z;

	memcpy(M[0], cs->M[0], 3 * sizeof(TYPE)), M[0][3] = 1, M[0][4] = 0, M[0][5] = 0;
	memcpy(M[1], cs->M[1], 3 * sizeof(TYPE)), M[1][3] = 0, M[1][4] = 1, M[1][5] = 0;
	memcpy(M[2], cs->M[2], 3 * sizeof(TYPE)), M[2][3] = 0, M[2][4] = 0, M[2][5] = 1;

	if (eliminate(M, 3, 6))
		return -1;

	memcpy(cs->Minv[0], M[0] + 3, 3 * sizeof(TYPE));
	memcpy(cs->Minv[1], M[1] + 3, 3 * sizeof(TYPE));
	memcpy(cs->Minv[2], M[2] + 3, 3 * sizeof(TYPE));

	return 0;
}


#define invert(Minv, M, n) invert_(n, &(Minv), &(M))
static int
invert_(size_t n, TYPE (*Minvp)[n][n], TYPE (*Mp)[n][n])
{
#define Minv (*Minvp)
#define M (*Mp)
#define J (*Jp)
	TYPE J[n][2 * n] = alloca(sizeof(TYPE[n][2 * n]));
	size_t i;
	for (i = 0; i < n; i++) {
		memcpy(J[i], M[i], n * sizeof(TYPE));
		memset(J[i] + n, 0, n * sizeof(TYPE));
		J[i][n + i] = 1;
	}
	if (eliminate(J, n, 2 * n))
		return -1;
	for (i = 0; i < n; i++)
		memcpy(Minv[i], J[i] + n, n * sizeof(TYPE));
	return 0;
#undef J
#undef M
#undef Minv
}


static TYPE
transfer_function_l_star(TYPE t)
{
	TYPE sign = 1;
	if (t < 0) {
		t = -t;
		sign = -1;
	}
	t = t > D(216.) / D(24389.) ? D(1.16) * xcbrt(t) - D(0.16) : t * D(24389.) / D(2700.);
	return t * sign;
}
 
static TYPE
invtransfer_function_l_star(TYPE t)
{
	TYPE sign = 1;
	if (t < 0) {
		t = -t;
		sign = -1;
	}
	t = t > D(0.08) ? (((D(1000000.) * t + D(480000.)) * t +
			    D(76800.)) * t + D(4096.)) / D(1560896.) :
		t * D(2700.) / D(24389.);
	return t * sign;
}

static TYPE
transfer_function_oetf_hlg(TYPE t)
{
	TYPE sign = 1;
	if (t < 0) {
		t = -t;
		sign = -1;
	}
	t = 12 * t <= 1 ? xsqrt(3 * t) :
		D(0.17883277) * xlog(t - D(0.02372241)) + D(1.004293468902569985701234145381);
	return t * sign;
}

static TYPE
invtransfer_function_oetf_hlg(TYPE t)
{
	TYPE sign = 1;
	if (t < 0) {
		t = -t;
		sign = -1;
	}
	t = t <= D(0.5) ? t * t / 3 :
		xexp(t - D(1.004293468902569985701234145381)) / D(0.17883277) + D(0.02372241);
	return t * sign;
}


static void
get_transfer_function(libcolour_colour_t *cs)
{
	if (cs->model == LIBCOLOUR_RGB) {
		switch (cs->rgb.colour_space) {
		case LIBCOLOUR_RGB_COLOUR_SPACE_ECI_RGB_V2:
			cs->rgb.TO_ENCODED_RED = cs->rgb.TO_ENCODED_GREEN = cs->rgb.TO_ENCODED_BLUE = transfer_function_l_star;
			cs->rgb.TO_DECODED_RED = cs->rgb.TO_DECODED_GREEN = cs->rgb.TO_DECODED_BLUE = invtransfer_function_l_star;
			break;
		case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_EOTF_PQ:
		case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OOTF_PQ:
		case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OETF_PQ:
		case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_EOTF_HLG:
		case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OOTF_HLG:
			/* TODO http://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.2100-0-201607-I!!PDF-E.pdf */
			break;
		case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OETF_HLG:
			cs->rgb.TO_ENCODED_RED = cs->rgb.TO_ENCODED_GREEN = cs->rgb.TO_ENCODED_BLUE = transfer_function_oetf_hlg;
			cs->rgb.TO_DECODED_RED = cs->rgb.TO_DECODED_GREEN = cs->rgb.TO_DECODED_BLUE = invtransfer_function_oetf_hlg;
			break;
		default:
			break;
		}
	}
}


int
libcolour_get_rgb_colour_space(libcolour_rgb_t *cs, libcolour_rgb_colour_space_t space)
{
#define XYY(XVALUE, YVALUE) (libcolour_ciexyy_t){.model = LIBCOLOUR_CIEXYY, .x = D(XVALUE), .y = D(YVALUE), .Y = 1}

	switch (space) {
	case LIBCOLOUR_RGB_COLOUR_SPACE_CUSTOM_FROM_MEASUREMENTS:
		if (get_matrices(cs))
			return -1;
		if (cs->encoding_type == LIBCOLOUR_ENCODING_TYPE_REGULAR)
			cs->TRANSITIONINV = cs->TRANSITION * cs->SLOPE;
		return 0;

	case LIBCOLOUR_RGB_COLOUR_SPACE_CUSTOM_FROM_MATRIX:
		if (invert(cs->Minv, cs->M, 3) || get_primaries(cs))
			return -1;
		if (cs->encoding_type == LIBCOLOUR_ENCODING_TYPE_REGULAR)
			cs->TRANSITIONINV = cs->TRANSITION * cs->SLOPE;
		return 0;

	case LIBCOLOUR_RGB_COLOUR_SPACE_CUSTOM_FROM_INV_MATRIX:
		if (invert(cs->M, cs->Minv, 3) || get_primaries(cs))
			return -1;
		if (cs->encoding_type == LIBCOLOUR_ENCODING_TYPE_REGULAR)
			cs->TRANSITIONINV = cs->TRANSITION * cs->SLOPE;
		return 0;

	case LIBCOLOUR_RGB_COLOUR_SPACE_SRGB:
		cs->red   = XYY(0.6400, 0.3300);
		cs->green = XYY(0.3000, 0.6000);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->OFFSET = D(0.055);
		cs->GAMMA = D(2.4);
		cs->SLOPE = D(12.92);
		cs->TRANSITION = D(0.0031306684425217108);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ADOBE_RGB:
		cs->red   = XYY(0.6400, 0.3300);
		cs->green = XYY(0.2100, 0.7100);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_APPLE_RGB:
		cs->red   = XYY(0.6250, 0.3400);
		cs->green = XYY(0.2800, 0.5950);
		cs->blue  = XYY(0.1550, 0.0700);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(1.8);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_BEST_RGB:
		cs->red   = XYY(0.7347, 0.2653);
		cs->green = XYY(0.2150, 0.7750);
		cs->blue  = XYY(0.1300, 0.0350);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_BETA_RGB:
		cs->red   = XYY(0.6888, 0.3112);
		cs->green = XYY(0.1986, 0.7551);
		cs->blue  = XYY(0.1265, 0.0352);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_BRUCE_RGB:
		cs->red   = XYY(0.6400, 0.3300);
		cs->green = XYY(0.2800, 0.6500);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_CIE_RGB:
		cs->red   = XYY(0.7350, 0.2650);
		cs->green = XYY(0.2740, 0.7170);
		cs->blue  = XYY(0.1670, 0.0090);
		cs->white = LIBCOLOUR_ILLUMINANT_E;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_COLORMATCH_RGB:
		cs->red   = XYY(0.6300, 0.3400);
		cs->green = XYY(0.2950, 0.6050);
		cs->blue  = XYY(0.1500, 0.0750);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(1.8);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_DCI_P3_D65:
		cs->red   = XYY(0.6380, 0.3200);
		cs->green = XYY(0.2650, 0.6900);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.6);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_DCI_P3_THEATER:
		cs->red   = XYY(0.6380, 0.3200);
		cs->green = XYY(0.2650, 0.6900);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = XYY(0.314, 0.351);
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.6);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_DON_RGB_4:
		cs->red   = XYY(0.6960, 0.3000);
		cs->green = XYY(0.2150, 0.7650);
		cs->blue  = XYY(0.1300, 0.0350);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ECI_RGB:
		cs->red   = XYY(0.6700, 0.3300);
		cs->green = XYY(0.2100, 0.7100);
		cs->blue  = XYY(0.1400, 0.0800);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(1.8);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ECI_RGB_V2:
		cs->red   = XYY(0.6700, 0.3300);
		cs->green = XYY(0.2100, 0.7100);
		cs->blue  = XYY(0.1400, 0.0800);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_CUSTOM;
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_EKTA_SPACE_PS5:
		cs->red   = XYY(0.6950, 0.3050);
		cs->green = XYY(0.2600, 0.7000);
		cs->blue  = XYY(0.1100, 0.0050);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.2);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_601_625_LINE:
		cs->red   = XYY(0.6400, 0.3300);
		cs->green = XYY(0.2900, 0.6000);
		cs->blue  = XYY(0.1500, 0.0060);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_601_525_LINE:
		cs->red   = XYY(0.6300, 0.3400);
		cs->green = XYY(0.3100, 0.5950);
		cs->blue  = XYY(0.1550, 0.0700);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_709:
		cs->red   = XYY(0.6300, 0.3300);
		cs->green = XYY(0.3000, 0.6000);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2020:
		cs->red   = XYY(0.7080, 0.2920);
		cs->green = XYY(0.1700, 0.7970);
		cs->blue  = XYY(0.1310, 0.0460);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_EOTF_PQ:
	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OOTF_PQ:
	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OETF_PQ:
	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_EOTF_HLG:
	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OOTF_HLG:
	case LIBCOLOUR_RGB_COLOUR_SPACE_ITU_R_BT_2100_OETF_HLG:
		cs->red   = XYY(0.7080, 0.2920);
		cs->green = XYY(0.1700, 0.7970);
		cs->blue  = XYY(0.1310, 0.0460);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_CUSTOM;
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_LIGHTROOM_RGB:
		cs->red   = XYY(0.7347, 0.2653);
		cs->green = XYY(0.1596, 0.8404);
		cs->blue  = XYY(0.0366, 0.0001);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_LINEAR;
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_NTSC_RGB:
		cs->red   = XYY(0.6700, 0.3300);
		cs->green = XYY(0.2100, 0.7100);
		cs->blue  = XYY(0.1400, 0.0800);
		cs->white = LIBCOLOUR_ILLUMINANT_C;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_PAL_SECAM_RGB:
		cs->red   = XYY(0.6400, 0.3300);
		cs->green = XYY(0.2900, 0.6000);
		cs->blue  = XYY(0.1500, 0.0600);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_PROPHOTO_RGB:
		cs->red   = XYY(0.7347, 0.2653);
		cs->green = XYY(0.1596, 0.8404);
		cs->blue  = XYY(0.0366, 0.0001);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(1.8);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_SGI_RGB:
		cs->red   = XYY(0.6250, 0.3400);
		cs->green = XYY(0.2800, 0.5950);
		cs->blue  = XYY(0.1550, 0.0700);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(1.47);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_SMPTE_240M_RGB:
		cs->red   = XYY(0.6300, 0.3400);
		cs->green = XYY(0.3100, 0.5950);
		cs->blue  = XYY(0.1550, 0.0700);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.1115721957735072);
		cs->SLOPE = D(4.0);
		cs->TRANSITION = D(0.022821585552393633);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_SMPTE_C_RGB:
		cs->red   = XYY(0.6300, 0.3400);
		cs->green = XYY(0.3100, 0.5950);
		cs->blue  = XYY(0.1550, 0.0700);
		cs->white = LIBCOLOUR_ILLUMINANT_D65;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_REGULAR;
		cs->GAMMA = 1 / D(0.45);
		cs->OFFSET = D(0.09929682680944);
		cs->SLOPE = D(4.5);
		cs->TRANSITION = D(0.018053968510807);
		break;

	case LIBCOLOUR_RGB_COLOUR_SPACE_WIDE_GAMUT_RGB:
		cs->red   = XYY(0.7350, 0.2650);
		cs->green = XYY(0.1150, 0.8260);
		cs->blue  = XYY(0.1570, 0.0180);
		cs->white = LIBCOLOUR_ILLUMINANT_D50;
		cs->encoding_type = LIBCOLOUR_ENCODING_TYPE_SIMPLE;
		cs->GAMMA = D(2.19921875);
		break;

	default:
		errno = EINVAL;
		return -1;
	}
	if (cs->encoding_type == LIBCOLOUR_ENCODING_TYPE_REGULAR)
		cs->TRANSITIONINV = cs->TRANSITION * cs->SLOPE;
	cs->colour_space = space;
	cs->white_r = cs->white_g = cs->white_b = 1;
	if (get_matrices(cs) || libcolour_proper((libcolour_colour_t *)cs))
		return -1;
	get_transfer_function((libcolour_colour_t *)cs);
	return 0;

#undef XYY
}


size_t
libcolour_marshal(const libcolour_colour_t *colour, void *buf)
{
	if (buf)
		*(int *)buf = MARSHAL_VERSION;
	switch (colour->model) {
#define X(C, T, N)\
		case C:\
			if (buf)\
				memcpy((char *)buf + sizeof(int), colour, sizeof(T));\
			return sizeof(int) + sizeof(T);
		LIST_MODELS(X)
#undef X
	default:
		errno = EINVAL;
		return 0;
	}
}


static size_t
libcolour_unmarshal_version_0_rgb(void *colour, const void *buf)
{
	libcolour_rgb_t *c = colour;
	struct old_rgb {
		enum libcolour_model model;
		TYPE R;
		TYPE G;
		TYPE B;
		int with_transfer;
		enum libcolour_encoding_type encoding_type;
		TYPE gamma;
		TYPE offset;
		TYPE slope;
		TYPE transition;
		TYPE transitioninv;
		TYPE (*to_encoded_red)(TYPE);
		TYPE (*to_decoded_red)(TYPE);
		TYPE (*to_encoded_green)(TYPE);
		TYPE (*to_decoded_green)(TYPE);
		TYPE (*to_encoded_blue)(TYPE);
		TYPE (*to_decoded_blue)(TYPE);
		libcolour_ciexyy_t red;
		libcolour_ciexyy_t green;
		libcolour_ciexyy_t blue;
		libcolour_ciexyy_t white;
		TYPE white_r;
		TYPE white_g;
		TYPE white_b;
		TYPE M[3][3];
		TYPE Minv[3][3];
		enum libcolour_rgb_colour_space colour_space;
	} old_c;
	if (c) {
		memcpy(&old_c, (const char *)buf + sizeof(int), sizeof(old_c));
		memset(&c->transfer, 0, sizeof(c->transfer));
		c->model = old_c.model;
		c->R = old_c.R;
		c->G = old_c.G;
		c->B = old_c.B;
		c->with_transfer = old_c.with_transfer;
		c->encoding_type = old_c.encoding_type;
		if (c->encoding_type == LIBCOLOUR_ENCODING_TYPE_SIMPLE) {
			c->transfer.simple.gamma = old_c.gamma;
		} else if (c->encoding_type == LIBCOLOUR_ENCODING_TYPE_REGULAR) {
			c->transfer.regular.gamma = old_c.gamma;
			c->transfer.regular.offset = old_c.offset;
			c->transfer.regular.slope = old_c.slope;
			c->transfer.regular.transition = old_c.transition;
			c->transfer.regular.transitioninv = old_c.transitioninv;
		} else if (c->encoding_type == LIBCOLOUR_ENCODING_TYPE_CUSTOM) {
			c->transfer.custom.to_encoded_red = old_c.to_encoded_red;
			c->transfer.custom.to_decoded_red = old_c.to_decoded_red;
			c->transfer.custom.to_encoded_green = old_c.to_encoded_green;
			c->transfer.custom.to_decoded_green = old_c.to_decoded_green;
			c->transfer.custom.to_encoded_blue = old_c.to_encoded_blue;
			c->transfer.custom.to_decoded_blue = old_c.to_decoded_blue;
		}
		c->red = old_c.red;
		c->green = old_c.green;
		c->blue = old_c.blue;
		c->white = old_c.white;
		c->white_r = old_c.white_r;
		c->white_g = old_c.white_g;
		c->white_b = old_c.white_b;
		c->M[0][0] = old_c.M[0][0];
		c->M[0][1] = old_c.M[0][1];
		c->M[0][2] = old_c.M[0][2];
		c->M[1][0] = old_c.M[1][0];
		c->M[1][1] = old_c.M[1][1];
		c->M[1][2] = old_c.M[1][2];
		c->M[2][0] = old_c.M[2][0];
		c->M[2][1] = old_c.M[2][1];
		c->M[2][2] = old_c.M[2][2];
		c->Minv[0][0] = old_c.Minv[0][0];
		c->Minv[0][1] = old_c.Minv[0][1];
		c->Minv[0][2] = old_c.Minv[0][2];
		c->Minv[1][0] = old_c.Minv[1][0];
		c->Minv[1][1] = old_c.Minv[1][1];
		c->Minv[1][2] = old_c.Minv[1][2];
		c->Minv[2][0] = old_c.Minv[2][0];
		c->Minv[2][1] = old_c.Minv[2][1];
		c->Minv[2][2] = old_c.Minv[2][2];
		c->colour_space = old_c.colour_space;
	}
	return sizeof(int) + sizeof(old_c);
}


size_t
libcolour_unmarshal(libcolour_colour_t *colour, const void *buf)
{
	enum libcolour_model model;
	size_t r;
	int ver;
	ver = *(const int *)buf;
	if (ver < 0 || ver > MARSHAL_VERSION) {
		errno = EINVAL;
		return 0;
	}
	model = *(const enum libcolour_model *)((const char *)buf + sizeof(int));
	switch (model) {
#define X(C, T, N)\
		case C:\
			if (C == LIBCOLOUR_RGB && ver == 0) {\
				r = libcolour_unmarshal_version_0_rgb(colour, buf);\
				break;\
			}\
			if (colour)\
				memcpy(colour, (const char *)buf + sizeof(int), sizeof(T));\
			r = sizeof(int) + sizeof(T);\
			break;
		LIST_MODELS(X)
#undef X
	default:
		errno = EINVAL;
		return 0;
	}
	if (colour) {
		if (colour->model == LIBCOLOUR_RGB) {
			colour->rgb.TO_ENCODED_RED = colour->rgb.TO_ENCODED_GREEN = colour->rgb.TO_ENCODED_BLUE = NULL;
			colour->rgb.TO_DECODED_RED = colour->rgb.TO_DECODED_GREEN = colour->rgb.TO_DECODED_BLUE = NULL;
		}
		get_transfer_function(colour);
	}
	return r;
}