Remove a much of stuff, change license, and add support for float and long double

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 1162 insertions, 0 deletions

diff --git a/convert-template.c b/convert-template.c
new file mode 100644
index 0000000..d06ccc0
--- /dev/null
+++ b/convert-template.c
@@ -0,0 +1,1162 @@
+/* See LICENSE file for copyright and license details. */
+
+#if defined(__GNUC__) && !defined(__clang__)
+# pragma GCC diagnostic ignored "-Wfloat-equal"
+#elif defined(__clang__)
+# pragma clang diagnostic ignored "-Wcomma"
+# pragma clang diagnostic ignored "-Wfloat-equal"
+# pragma clang diagnostic ignored "-Wvla"
+# pragma clang diagnostic ignored "-Wtautological-compare"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+# pragma clang diagnostic ignored "-Wfloat-conversion"
+# pragma clang diagnostic ignored "-Wconversion"
+# pragma clang diagnostic ignored "-Wdouble-promotion"
+# pragma clang diagnostic ignored "-Wswitch-enum"
+# pragma clang diagnostic ignored "-Wcast-align"
+#endif
+
+
+#define PI          D(3.14159265358979323846)
+#define PI2         (2 * D(3.14159265358979323846))
+#define WASDIV0(X)  (xisinf(X) || xisnan(X))
+
+#define REGULAR(S, T)    ((T) <= (S)->transition ? (S)->slope * (T) : (1 + (S)->offset) * xpow((T), 1 / (S)->gamma) - (S)->offset)
+#define INVREGULAR(S, T) ((T) <= (S)->transitioninv ? (T) / (S)->slope : xpow(((T) + (S)->offset) / (1 + (S)->offset), (S)->gamma))
+
+#define TRANSFORM(X, Y, Z, A, B, C, R1C1, R1C2, R1C3, R2C1, R2C2, R2C3, R3C1, R3C2, R3C3)\
+	do {\
+		TYPE a__ = (A), b__ = (B), c__ = (C);\
+		(X) = D(R1C1) * a__ + D(R1C2) * b__ + D(R1C3) * c__;\
+		(Y) = D(R2C1) * a__ + D(R2C2) * b__ + D(R2C3) * c__;\
+		(Z) = D(R3C1) * a__ + D(R3C2) * b__ + D(R3C3) * c__;\
+	} while (0)
+
+
+
+static void to_rgb(const libcolour_colour_t *restrict from, libcolour_rgb_t *restrict to);
+static void to_srgb(const libcolour_colour_t *restrict from, libcolour_srgb_t *restrict to);
+static void to_ciexyy(const libcolour_colour_t *restrict from, libcolour_ciexyy_t *restrict to);
+static void to_ciexyz(const libcolour_colour_t *restrict from, libcolour_ciexyz_t *restrict to);
+static void to_cielab(const libcolour_colour_t *restrict from, libcolour_cielab_t *restrict to);
+static void to_cieluv(const libcolour_colour_t *restrict from, libcolour_cieluv_t *restrict to);
+static void to_cielchuv(const libcolour_colour_t *restrict from, libcolour_cielchuv_t *restrict to);
+static void to_yiq(const libcolour_colour_t *restrict from, libcolour_yiq_t *restrict to);
+static void to_ydbdr(const libcolour_colour_t *restrict from, libcolour_ydbdr_t *restrict to);
+static void to_yuv(const libcolour_colour_t *restrict from, libcolour_yuv_t *restrict to);
+static void to_ypbpr(const libcolour_colour_t *restrict from, libcolour_ypbpr_t *restrict to);
+static void to_ycgco(const libcolour_colour_t *restrict from, libcolour_ycgco_t *restrict to);
+static void to_cie1960ucs(const libcolour_colour_t *restrict from, libcolour_cie1960ucs_t *restrict to);
+static void to_cieuvw(const libcolour_colour_t *restrict from, libcolour_cieuvw_t *restrict to);
+
+
+
+static void
+ciexyz_to_rgb(const libcolour_ciexyz_t *restrict from, libcolour_rgb_t *restrict to)
+{
+	TYPE X = from->X, Y = from->Y, Z = from->Z;
+	to->R = to->Minv[0][0] * X + to->Minv[0][1] * Y + to->Minv[0][2] * Z;
+	to->G = to->Minv[1][0] * X + to->Minv[1][1] * Y + to->Minv[1][2] * Z;
+	to->B = to->Minv[2][0] * X + to->Minv[2][1] * Y + to->Minv[2][2] * Z;
+}
+
+
+static void
+rgb_encode(libcolour_rgb_t *restrict colour, const libcolour_rgb_t *restrict space)
+{
+	TYPE r_sign = 1, g_sign = 1, b_sign = 1;
+	switch (space->encoding_type) {
+	case LIBCOLOUR_ENCODING_TYPE_LINEAR:
+		break;
+	case LIBCOLOUR_ENCODING_TYPE_SIMPLE:
+	case LIBCOLOUR_ENCODING_TYPE_REGULAR:
+		if (colour->R < 0)  r_sign = -1, colour->R = -colour->R;
+		if (colour->G < 0)  g_sign = -1, colour->G = -colour->G;
+		if (colour->B < 0)  b_sign = -1, colour->B = -colour->B;
+		if (space->encoding_type == LIBCOLOUR_ENCODING_TYPE_SIMPLE) {
+			colour->R = xpow(colour->R, 1 / space->gamma);
+			colour->G = xpow(colour->G, 1 / space->gamma);
+			colour->B = xpow(colour->B, 1 / space->gamma);
+		} else {
+			colour->R = REGULAR(space, colour->R);
+			colour->G = REGULAR(space, colour->G);
+			colour->B = REGULAR(space, colour->B);
+		}
+		colour->R *= r_sign;
+		colour->G *= g_sign;
+		colour->B *= b_sign;
+		break;
+	case LIBCOLOUR_ENCODING_TYPE_CUSTOM:
+		colour->R = (space->to_encoded_red)(colour->R);
+		colour->G = (space->to_encoded_green)(colour->G);
+		colour->B = (space->to_encoded_blue)(colour->B);
+		break;
+	default:
+		fprintf(stderr, "libcolour: invalid encoding type\n");
+		abort();
+	}
+}
+
+static void
+rgb_decode(libcolour_rgb_t *restrict colour, const libcolour_rgb_t *restrict space)
+{
+	TYPE r_sign = 1, g_sign = 1, b_sign = 1;
+	switch (space->encoding_type) {
+	case LIBCOLOUR_ENCODING_TYPE_LINEAR:
+		break;
+	case LIBCOLOUR_ENCODING_TYPE_SIMPLE:
+	case LIBCOLOUR_ENCODING_TYPE_REGULAR:
+		if (colour->R < 0)  r_sign = -1, colour->R = -colour->R;
+		if (colour->G < 0)  g_sign = -1, colour->G = -colour->G;
+		if (colour->B < 0)  b_sign = -1, colour->B = -colour->B;
+		if (space->encoding_type == LIBCOLOUR_ENCODING_TYPE_SIMPLE) {
+			colour->R = xpow(colour->R, space->gamma);
+			colour->G = xpow(colour->G, space->gamma);
+			colour->B = xpow(colour->B, space->gamma);
+		} else {
+			colour->R = INVREGULAR(space, colour->R);
+			colour->G = INVREGULAR(space, colour->G);
+			colour->B = INVREGULAR(space, colour->B);
+		}
+		colour->R *= r_sign;
+		colour->G *= g_sign;
+		colour->B *= b_sign;
+		break;
+	case LIBCOLOUR_ENCODING_TYPE_CUSTOM:
+		colour->R = (space->to_decoded_red)(colour->R);
+		colour->G = (space->to_decoded_green)(colour->G);
+		colour->B = (space->to_decoded_blue)(colour->B);
+		break;
+	default:
+		fprintf(stderr, "libcolour: invalid encoding type\n");
+		abort();
+	}
+}
+
+static int
+rgb_same_transfer(const libcolour_rgb_t *restrict a, const libcolour_rgb_t *restrict b)
+{
+	if (a->encoding_type != b->encoding_type)
+		return 0;
+	switch (a->encoding_type) {
+	case LIBCOLOUR_ENCODING_TYPE_SIMPLE:
+		return a->gamma == b->gamma;
+	case LIBCOLOUR_ENCODING_TYPE_REGULAR:
+		return a->gamma      == b->gamma  &&
+		       a->offset     == b->offset &&
+		       a->slope      == b->slope  &&
+		       a->transition == b->transition;
+	case LIBCOLOUR_ENCODING_TYPE_CUSTOM:
+		return a->to_encoded_red   == b->to_encoded_red   &&
+		       a->to_encoded_green == b->to_encoded_green &&
+		       a->to_encoded_blue  == b->to_encoded_blue  &&
+		       a->to_decoded_red   == b->to_decoded_red   &&
+		       a->to_decoded_green == b->to_decoded_green &&
+		       a->to_decoded_blue  == b->to_decoded_blue;
+	default:
+		return 1;
+	}
+}
+
+static void
+to_rgb(const libcolour_colour_t *restrict from, libcolour_rgb_t *restrict to)
+{
+	int have_transfer = 0, with_transfer = to->with_transfer;
+	libcolour_ciexyz_t tmp;
+	switch (from->model) {
+	case LIBCOLOUR_CIEXYZ:
+		ciexyz_to_rgb(&from->ciexyz, to);
+		break;
+	case LIBCOLOUR_RGB:
+		if (!memcmp(from->rgb.M, to->M, sizeof(TYPE[3][3]))) {
+			have_transfer = from->rgb.with_transfer;
+			to->R = from->rgb.R;
+			to->G = from->rgb.G;
+			to->B = from->rgb.B;
+			if (have_transfer && with_transfer && !rgb_same_transfer(&from->rgb, to))
+				rgb_decode(to, &from->rgb), have_transfer = 0;
+			break;
+		}
+		/* fall through */
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp);
+		ciexyz_to_rgb(&tmp, to);
+		break;
+	}
+
+	if (have_transfer != with_transfer) {
+		if (with_transfer)
+			rgb_encode(to, to);
+		else
+			rgb_decode(to, &from->rgb);
+	}
+}
+
+
+static void
+ciexyz_to_srgb(const libcolour_ciexyz_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	TRANSFORM(to->R, to->G, to->B, from->X, from->Y, from->Z,
+		   3.240446254647737500675930277794, -1.537134761820080575134284117667, -0.498530193022728718155178739835,
+		  -0.969266606244679751469561779231,  1.876011959788370209167851498933,  0.041556042214430065351304932619,
+		   0.055643503564352832235773149705, -0.204026179735960239147729566866,  1.057226567722703292062647051353);
+}
+
+static inline TYPE
+srgb_encode(TYPE t)
+{
+	TYPE sign = 1;
+	if (t < 0) {
+		t = -t;
+		sign = -1;
+	}
+	t = t <= D(0.0031306684425217108) ? D(12.92) * t
+		: D(1.055) * xpow(t, 1 / D(2.4)) - D(0.055);
+	return t * sign;
+}
+
+static inline TYPE
+srgb_decode(TYPE t)
+{
+	TYPE sign = 1;
+	if (t < 0) {
+		t = -t;
+		sign = -1;
+	}
+	t = t <= D(0.0031306684425217108) * D(12.92) ? t / D(12.92)
+		: xpow((t + D(0.055)) / D(1.055), D(2.4));
+	return t * sign;
+}
+
+static void
+srgb_to_srgb(const libcolour_srgb_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	if (from->with_transfer == to->with_transfer) {
+		*to = *from;
+	} else if (to->with_transfer) {
+		to->R = srgb_encode(from->R);
+		to->G = srgb_encode(from->G);
+		to->B = srgb_encode(from->B);
+	} else {
+		to->R = srgb_decode(from->R);
+		to->G = srgb_decode(from->G);
+		to->B = srgb_decode(from->B);
+	}
+}
+
+static void
+yiq_to_srgb(const libcolour_yiq_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	TRANSFORM(to->R, to->G, to->B, from->Y, from->I, from->Q,
+		  1,  0.95629483232089407263032398986979387700557708740234,  0.62102512544472865396727456754888407886028289794922,
+		  1, -0.27212147408397735492968649850809015333652496337891, -0.64738095351761570928061928498209454119205474853516,
+		  1, -1.10698990856712820018969978264067322015762329101562,  1.70461497549882934343656870623817667365074157714844);
+	/* ⎛1    1000 cos 33° / 877                                  1000 sin 33° / 877                               ⎞
+	   ⎜1    9500 sin 33° / 24067 - 299000 * cos 33° / 514799    -9500 cos 33° / 24067 - 299000 * sin 33° / 514799⎟
+	   ⎝1    -250 sin 33° / 123                                  250 cos 33° / 123                                ⎠
+	*/
+}
+
+static void
+ydbdr_to_srgb(const libcolour_ydbdr_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	TRANSFORM(to->R, to->G, to->B, from->Y, from->Db, from->Dr,
+		  1,  0.000092303716148, -0.525912630661865,
+		  1, -0.129132898890509,  0.267899328207599,
+		  1,  0.664679059978955, -0.000079202543533);
+}
+
+static void
+ypbpr_to_srgb(const libcolour_ypbpr_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	TYPE Y = from->Y, Pb = from->Pb, Pr = from->Pr;
+	to->R = Pr + Y;
+	to->B = Pb + Y;
+	to->G = (Y - to->R * D(0.2126) - to->B * D(0.0722)) / D(0.7152);
+}
+
+static void
+yuv_to_srgb(const libcolour_yuv_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	TRANSFORM(to->R, to->G, to->B, from->Y, from->U, from->V,
+		  1,  0.00028328010485821202317155420580263580632163211703,  1.14070449590558520291949662350816652178764343261719,
+		  1, -0.39630886669497211727275498560629785060882568359375, -0.58107364288228224857846271333983168005943298339844,
+		  1,  2.03990003507541306504435851820744574069976806640625,  0.00017179031692307700847528739718228507626918144524);
+}
+
+static void
+ycgco_to_srgb(const libcolour_ycgco_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	TYPE Y = from->Y, Cg = from->Cg, Co = from->Co;
+	to->R = Y - Cg + Co;
+	to->G = Y + Cg;
+	to->B = Y - Cg - Co;
+}
+
+static void
+other_to_srgb(const libcolour_colour_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	libcolour_ciexyz_t tmp;
+	tmp.model = LIBCOLOUR_CIEXYZ;
+	to_ciexyz(from, &tmp);
+	ciexyz_to_srgb(&tmp, to);
+}
+
+static void
+to_srgb(const libcolour_colour_t *restrict from, libcolour_srgb_t *restrict to)
+{
+	libcolour_srgb_t tmp;
+	switch (from->model) {
+	case LIBCOLOUR_CIEXYZ:
+		ciexyz_to_srgb(&from->ciexyz, to);
+		break;
+	case LIBCOLOUR_SRGB:
+		srgb_to_srgb(&from->srgb, to);
+		return;
+	case LIBCOLOUR_YIQ:
+		yiq_to_srgb(&from->yiq, to);
+		break;
+	case LIBCOLOUR_YDBDR:
+		ydbdr_to_srgb(&from->ydbdr, to);
+		break;
+	case LIBCOLOUR_YPBPR:
+		ypbpr_to_srgb(&from->ypbpr, to);
+		break;
+	case LIBCOLOUR_YUV:
+		yuv_to_srgb(&from->yuv, to);
+		break;
+	case LIBCOLOUR_YCGCO:
+		ycgco_to_srgb(&from->ycgco, to);
+		break;
+	default:
+		other_to_srgb(from, to);
+		break;
+	}
+	if (to->with_transfer) {
+		tmp = *to;
+		tmp.with_transfer = 0;
+		srgb_to_srgb(&tmp, to);
+	}
+}
+
+
+static void
+ciexyz_to_ciexyy(const libcolour_ciexyz_t *restrict from, libcolour_ciexyy_t *restrict to)
+{
+	TYPE X = from->X, Y = from->Y, Z = from->Z;
+	TYPE s = X + Y + Z;
+	to->x = X / s;
+	to->y = Y / s;
+	to->Y = Y;
+	if (WASDIV0(to->x) || WASDIV0(to->y))
+		to->x = to->y = 0;
+}
+
+static void
+other_to_ciexyy(const libcolour_colour_t *restrict from, libcolour_ciexyy_t *restrict to)
+{
+	libcolour_ciexyz_t tmp;
+	tmp.model = LIBCOLOUR_CIEXYZ;
+	to_ciexyz(from, &tmp);
+	ciexyz_to_ciexyy(&tmp, to);
+}
+
+static void
+srgb_to_ciexyy(const libcolour_srgb_t *restrict from, libcolour_ciexyy_t *restrict to)
+{
+	libcolour_srgb_t tmp;
+	tmp.model = LIBCOLOUR_SRGB;
+	if (from->with_transfer) {
+		tmp.with_transfer = 0;
+		to_srgb((const libcolour_colour_t*)from, &tmp);
+	} else {
+		tmp = *from;
+	}
+	if (tmp.R == 0 && tmp.G == 0 && tmp.B == 0) {
+		to->x = D(0.31272660439158);
+		to->y = D(0.32902315240275);
+		to->Y = 0;
+	} else {
+		other_to_ciexyy((const libcolour_colour_t*)&tmp, to);
+	}
+}
+
+static void
+to_ciexyy(const libcolour_colour_t *restrict from, libcolour_ciexyy_t *restrict to)
+{
+	switch (from->model) {
+	case LIBCOLOUR_CIEXYY:
+		*to = from->ciexyy;
+		return;
+	case LIBCOLOUR_CIEXYZ:
+		ciexyz_to_ciexyy(&from->ciexyz, to);
+		return;
+	case LIBCOLOUR_SRGB:
+		srgb_to_ciexyy(&from->srgb, to);
+		return;
+	default:
+		other_to_ciexyy(from, to);
+		return;
+	}
+}
+
+
+static void
+rgb_to_ciexyz(const libcolour_rgb_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	libcolour_rgb_t tmp;
+	TYPE R, G, B;
+	if (from->with_transfer) {
+		tmp = *from;
+		tmp.with_transfer = 0;
+		to_rgb((const libcolour_colour_t *)from, &tmp);
+		R = tmp.R, G = tmp.G, B = tmp.B;
+	} else {
+		R = from->R, G = from->G, B = from->B;
+	}
+	to->X = from->M[0][0] * R + from->M[0][1] * G + from->M[0][2] * B;
+	to->Y = from->M[1][0] * R + from->M[1][1] * G + from->M[1][2] * B;
+	to->Z = from->M[2][0] * R + from->M[2][1] * G + from->M[2][2] * B;
+}
+
+static void srgb_to_ciexyz(const libcolour_srgb_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	libcolour_srgb_t tmp;
+	TYPE R, G, B;
+	if (from->with_transfer) {
+		tmp.model = LIBCOLOUR_SRGB;
+		tmp.with_transfer = 0;
+		to_srgb((const libcolour_colour_t*)from, &tmp);
+		R = tmp.R, G = tmp.G, B = tmp.B;
+	} else {
+		R = from->R, G = from->G, B = from->B;
+	}
+	TRANSFORM(to->X, to->Y, to->Z, R, G, B,
+		  0.412457445582367576708548995157, 0.357575865245515878143578447634, 0.180437247826399665973085006954,
+		  0.212673370378408277403536885686, 0.715151730491031756287156895269, 0.072174899130559869164791564344,
+		  0.019333942761673460208893260415, 0.119191955081838593666354597644, 0.950302838552371742508739771438);
+}
+
+static void
+ciexyy_to_ciexyz(const libcolour_ciexyy_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TYPE x = from->x, y = from->y, Y = from->Y;
+	TYPE Yy = Y / y;
+	if (WASDIV0(Yy)) {
+		to->X = to->Y = to->Z = Y;
+	} else {
+		to->X = x * Yy;
+		to->Y = Y;
+		to->Z = (1 - x - y) * Yy;
+	}
+}
+
+static inline TYPE
+cielab_finv(TYPE t)
+{
+	return (t > D(6.) / D(29.)) ? t * t * t : (t - D(4.) / D(29.)) * 108 / 841;
+}
+
+static void
+cielab_to_ciexyz(const libcolour_cielab_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TYPE L = from->L, a = from->a, b = from->b;
+	to->Y = (L + 16) / 116;
+	to->X = to->Y + a / 500;
+	to->Z = to->Y - b / 200;
+	to->X = cielab_finv(to->X) * D(0.95047);
+	to->Y = cielab_finv(to->Y);
+	to->Z = cielab_finv(to->Z) * D(1.08883);
+}
+
+static void
+cieluv_to_ciexyz(const libcolour_cieluv_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TYPE X = from->white.X, Y = from->white.Y, L = from->L, L13 = from->L * 13;
+	TYPE t = X + 15 * Y + 3 * from->white.Z;
+	TYPE u = from->u / L13 + 4 * X / t;
+	TYPE v = from->v / L13 + 9 * Y / t;
+	if (L <= 8) {
+		Y *= L * 27 / 24389;
+	} else {
+		L = (L + 16) / 116;
+		Y *= L * L * L;
+	}
+	to->X = D(2.25) * Y * u / v;
+	to->Y = Y;
+	to->Z = Y * (3 / v - D(0.75) * u / v - 5);
+}
+
+static void
+cielchuv_to_ciexyz(const libcolour_cielchuv_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	libcolour_cieluv_t tmp;
+	tmp.model = LIBCOLOUR_CIELUV;
+	tmp.white = from->white;
+	to_cieluv((const libcolour_colour_t*)from, &tmp);
+	cieluv_to_ciexyz(&tmp, to);
+}
+
+static void
+yiq_to_ciexyz(const libcolour_yiq_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TRANSFORM(to->X, to->Y, to->Z, from->Y, from->I, from->Q,
+		   0.95047055865428309306963683411595411598682403564453,
+		   0.09738463974178063198294807989441324025392532348633,
+		   0.33223466706854809515903070860076695680618286132812,
+		   0.99999999999999988897769753748434595763683319091797,
+		  -0.07112658301916767455974621725545148365199565887451,
+		  -0.20786968876398304040264974901219829916954040527344,
+		   1.08882873639588373393394249433185905218124389648438,
+		  -1.06592139332461721679123911599162966012954711914062,
+		   1.55474471255181900808395312196807935833930969238281);
+}
+
+static void
+ydbdr_to_ciexyz(const libcolour_ydbdr_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TRANSFORM(to->X, to->Y, to->Z, from->Y, from->Db, from->Dr,
+		   0.95047055865428309306963683411595411598682403564453,
+		   0.07379612357298576119646327242662664502859115600586,
+		  -0.12113653724874726136384595065464964136481285095215,
+		   0.99999999999999988897769753748434595763683319091797,
+		  -0.04435684145428285540813106990754022262990474700928,
+		   0.07973534004202506575431641522300196811556816101074,
+		   1.08882873639588373393394249433185905218124389648438,
+		   0.61625657933494271123464613992837257683277130126953,
+		   0.02168821359337728266192257819966471288353204727173);
+}
+
+static void
+yuv_to_ciexyz(const libcolour_yuv_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TRANSFORM(to->X, to->Y, to->Z, from->Y, from->U, from->V,
+		   0.95047055865428309306963683411595411598682403564453,
+		   0.22648030324549334180161963558930438011884689331055,
+		   0.26274514929253273143316960158699657768011093139648,
+		   0.99999999999999988897769753748434595763683319091797,
+		  -0.13613114642319409930415474718756740912795066833496,
+		  -0.17294595255115238763288232348713790997862815856934,
+		   1.08882873639588373393394249433185905218124389648438,
+		   1.89129144197893928058817891724174842238426208496094,
+		  -0.04704173528403532422714761196402832865715026855469);
+}
+
+static void
+ypbpr_to_ciexyz(const libcolour_ypbpr_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TRANSFORM(to->X, to->Y, to->Z, from->Y, from->Pb, from->Pr,
+		   0.95047055865428298204733437160030007362365722656250,
+		   0.14433968424876231217979238863335922360420227050781,
+		   0.30616461986760712399302519770571961998939514160156,
+		   0.99999999999999977795539507496869191527366638183594,
+		  -0.00002022802471486617736928792510298080742359161377,
+		   0.00008771894888734421691367515450110659003257751465,
+		   1.08882873639588373393394249433185905218124389648438,
+		   0.93827031735982591165168287261622026562690734863281,
+		  -0.01609699914324668607035206946420657914131879806519);
+}
+
+static void
+ycgco_to_ciexyz(const libcolour_ycgco_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TRANSFORM(to->X, to->Y, to->Z, from->Y, from->Cg, from->Co,
+		   0.95047055865428309306963683411595411598682403564453,
+		  -0.23531882816325136453805555447615915909409523010254,
+		   0.23202019775596791073546398820326430723071098327637,
+		   0.99999999999999988897769753748434595763683319091797,
+		   0.43030346098206362359661625305307097733020782470703,
+		   0.14049847124784842211653312915586866438388824462891,
+		   1.08882873639588373393394249433185905218124389648438,
+		  -0.85044482623220662986796014592982828617095947265625,
+		  -0.93096889579069830311652822274481877684593200683594);
+}
+
+static void
+cie1960ucs_to_ciexyz(const libcolour_cie1960ucs_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	TYPE u = from->u, v = from->v, Y = from->Y;
+	to->X = D(1.5) * Y * u / v;
+	to->Y = Y;
+	to->Z = (4 * Y - Y * u - 10 * Y * v) / (2 * v);
+}
+
+static void
+cieuvw_to_ciexyz(const libcolour_cieuvw_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	libcolour_cie1960ucs_t tmp;
+	tmp.model = LIBCOLOUR_CIE1960UCS;
+	to_cie1960ucs((const libcolour_colour_t *)from, &tmp);
+	cie1960ucs_to_ciexyz(&tmp, to);
+}
+
+static void
+other_to_ciexyz(const libcolour_colour_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	libcolour_srgb_t tmp;
+	tmp.model = LIBCOLOUR_SRGB;
+	tmp.with_transfer = 0;
+	to_srgb(from, &tmp);
+	srgb_to_ciexyz(&tmp, to);
+}
+
+static void to_ciexyz(const libcolour_colour_t *restrict from, libcolour_ciexyz_t *restrict to)
+{
+	switch (from->model) {
+	case LIBCOLOUR_RGB:
+		rgb_to_ciexyz(&from->rgb, to);
+		break;
+	case LIBCOLOUR_SRGB:
+		srgb_to_ciexyz(&from->srgb, to);
+		break;
+	case LIBCOLOUR_CIEXYY:
+		ciexyy_to_ciexyz(&from->ciexyy, to);
+		break;
+	case LIBCOLOUR_CIEXYZ:
+		*to = from->ciexyz;
+		break;
+	case LIBCOLOUR_CIELAB:
+		cielab_to_ciexyz(&from->cielab, to);
+		break;
+	case LIBCOLOUR_CIELUV:
+		cieluv_to_ciexyz(&from->cieluv, to);
+		break;
+	case LIBCOLOUR_CIELCHUV:
+		cielchuv_to_ciexyz(&from->cielchuv, to);
+		break;
+	case LIBCOLOUR_YIQ:
+		yiq_to_ciexyz(&from->yiq, to);
+		break;
+	case LIBCOLOUR_YDBDR:
+		ydbdr_to_ciexyz(&from->ydbdr, to);
+		break;
+	case LIBCOLOUR_YUV:
+		yuv_to_ciexyz(&from->yuv, to);
+		break;
+	case LIBCOLOUR_YPBPR:
+		ypbpr_to_ciexyz(&from->ypbpr, to);
+		break;
+	case LIBCOLOUR_YCGCO:
+		ycgco_to_ciexyz(&from->ycgco, to);
+		break;
+	case LIBCOLOUR_CIE1960UCS:
+		cie1960ucs_to_ciexyz(&from->cie1960ucs, to);
+		break;
+	case LIBCOLOUR_CIEUVW:
+		cieuvw_to_ciexyz(&from->cieuvw, to);
+		break;
+	default:
+		other_to_ciexyz(from, to);
+		break;
+	}
+}
+
+
+static inline TYPE
+cielab_f(TYPE t)
+{
+	return (t > D(216.) / D(24389.)) ? xcbrt(t) : t * D(841.) / D(108.) + D(4.) / D(29.);
+}
+
+static void
+ciexyz_to_cielab(const libcolour_ciexyz_t *restrict from, libcolour_cielab_t *restrict to)
+{
+	TYPE X = from->X, Y = from->Y, Z = from->Z;
+	X /= D(0.95047);
+	Z /= D(1.08883);
+	Y = cielab_f(Y);
+	to->L = 116 * Y - 16;
+	to->a = 500 * (cielab_f(X) - Y);
+	to->b = 200 * (Y - cielab_f(Z));
+}
+
+static void
+other_to_cielab(const libcolour_colour_t *restrict from, libcolour_cielab_t *restrict to)
+{
+	libcolour_ciexyz_t tmp;
+	tmp.model = LIBCOLOUR_CIEXYZ;
+	to_ciexyz(from, &tmp);
+	ciexyz_to_cielab(&tmp, to);
+}
+
+static void
+to_cielab(const libcolour_colour_t *restrict from, libcolour_cielab_t *restrict to)
+{
+	switch (from->model) {
+	case LIBCOLOUR_CIEXYZ:
+		ciexyz_to_cielab(&from->ciexyz, to);
+		return;
+	case LIBCOLOUR_CIELAB:
+		*to = from->cielab;
+		return;
+	default:
+		other_to_cielab(from, to);
+		return;
+	}
+}
+
+
+static void
+ciexyz_to_cieluv(const libcolour_ciexyz_t *restrict from, libcolour_cieluv_t *restrict to)
+{
+	TYPE t, u, v, y, y2;
+	t = to->white.X + 15 * to->white.Y + 3 * to->white.Z;
+	u = 4 * to->white.X / t;
+	v = 9 * to->white.Y / t;
+	t = from->X + 15 * from->Y + 3 * from->Z;
+	u = 4 * from->X / t - u;
+	v = 9 * from->Y / t - v;
+	y = from->Y / to->white.Y;
+	y2 = y * 24389;
+	y = y2 <= 216 ? y2 / 27 : xcbrt(y) * 116 - 16;
+	to->L = y;
+	y *= 13;
+	to->u = u * y;
+	to->v = v * y;
+}
+
+static void
+cielchuv_to_cieluv(const libcolour_cielchuv_t *restrict from, libcolour_cieluv_t *restrict to)
+{
+	libcolour_ciexyz_t tmp;
+	libcolour_cielchuv_t tmp2;
+	TYPE L, C, h;
+	if (to->white.X != from->white.X || to->white.Y != from->white.Y || to->white.Z != from->white.Z) {
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		tmp2.model = LIBCOLOUR_CIELCHUV;
+		tmp2.white = to->white;
+		tmp2.one_revolution = PI2;
+		to_ciexyz((const libcolour_colour_t*)from, &tmp);
+		to_cielchuv((const libcolour_colour_t*)&tmp, &tmp2);
+		L = tmp2.L, C = tmp2.C, h = tmp2.h;
+	} else {
+		L = from->L, C = from->C, h = from->h * PI2 / from->one_revolution;
+	}
+	to->L = L;
+	to->u = C * xcos(h);
+	to->v = C * xsin(h);
+}
+
+static void
+other_to_cieluv(const libcolour_colour_t *restrict from, libcolour_cieluv_t *restrict to)
+{
+	libcolour_ciexyz_t tmp;
+	tmp.model = LIBCOLOUR_CIEXYZ;
+	to_ciexyz(from, &tmp);
+	ciexyz_to_cieluv(&tmp, to);
+}
+
+static void
+to_cieluv(const libcolour_colour_t *restrict from, libcolour_cieluv_t *restrict to)
+{
+	switch (from->model) {
+	case LIBCOLOUR_CIEXYZ:
+		ciexyz_to_cieluv(&from->ciexyz, to);
+		break;
+	case LIBCOLOUR_CIELCHUV:
+		cielchuv_to_cieluv(&from->cielchuv, to);
+		break;
+	case LIBCOLOUR_CIELUV:
+		if (to->white.X == from->cieluv.white.X &&
+		    to->white.Y == from->cieluv.white.Y &&
+		    to->white.Z == from->cieluv.white.Z) {
+			*to = from->cieluv;
+			break;
+		}
+		/* fall through */
+	default:
+		other_to_cieluv(from, to);
+		break;
+	}
+}
+
+
+static void
+cieluv_to_cielchuv(const libcolour_cieluv_t *restrict from, libcolour_cielchuv_t *restrict to)
+{
+	libcolour_cieluv_t tmp;
+	TYPE L, u, v;
+	if (to->white.X != from->white.X || to->white.Y != from->white.Y || to->white.Z != from->white.Z) {
+		tmp.model = LIBCOLOUR_CIELUV;
+		tmp.white = to->white;
+		to_cieluv((const libcolour_colour_t *)from, &tmp);
+		L = tmp.L, u = tmp.u, v = tmp.v;
+	} else {
+		L = from->L, u = from->u, v = from->v;
+	}
+	to->L = L;
+	to->C = xsqrt(u * u + v * v);
+	to->h = xatan2(v, u) / PI2 * to->one_revolution;
+	if (!WASDIV0(to->h) && (to->h < 0))
+		to->h += to->one_revolution;
+}
+
+static void
+other_to_cielchuv(const libcolour_colour_t *restrict from, libcolour_cielchuv_t *restrict to)
+{
+	libcolour_cieluv_t tmp;
+	tmp.model = LIBCOLOUR_CIELUV;
+	tmp.white = to->white;
+	to_cieluv(from, &tmp);
+	cieluv_to_cielchuv(&tmp, to);
+}
+
+static void
+to_cielchuv(const libcolour_colour_t *restrict from, libcolour_cielchuv_t *restrict to)
+{
+	TYPE one_revolution;
+	switch (from->model) {
+	case LIBCOLOUR_CIELUV:
+		cieluv_to_cielchuv(&from->cieluv, to);
+		break;
+	case LIBCOLOUR_CIELCHUV:
+		if (to->white.X == from->cielchuv.white.X &&
+		    to->white.Y == from->cielchuv.white.Y &&
+		    to->white.Z == from->cielchuv.white.Z) {
+			if (to->one_revolution == from->cielchuv.one_revolution) {
+				*to = from->cielchuv;
+			} else {
+				one_revolution = to->one_revolution;
+				*to = from->cielchuv;
+				to->one_revolution = one_revolution;
+				to->h = to->h / from->cielchuv.one_revolution * one_revolution;
+			}
+			break;
+		}
+		/* fall through */
+	default:
+		other_to_cielchuv(from, to);
+		break;
+	}
+}
+
+
+static void
+to_yiq(const libcolour_colour_t *restrict from, libcolour_yiq_t *restrict to)
+{
+	libcolour_colour_t tmp = *from;
+	switch (from->model) {
+	case LIBCOLOUR_YIQ:
+		*to = from->yiq;
+		break;
+	case LIBCOLOUR_SRGB:
+		if (tmp.srgb.with_transfer) {
+			tmp.srgb.with_transfer = 0;
+			to_srgb(from, &tmp.srgb);
+		}
+		TRANSFORM(to->Y, to->I, to->Q, tmp.srgb.R, tmp.srgb.G, tmp.srgb.B, 0.299, 0.587, 0.114,
+			   0.59571613491277464191853141528554260730743408203125,  /* (0.877 cos 33°)(1 - 0.299) - (0.492 sin 33°)(-0.299) */
+			  -0.27445283783925644716106262421817518770694732666016,  /* (0.877 cos 33°)(-0.587)    - (0.492 sin 33°)(-0.587) */
+			  -0.32126329707351808373516632855171337723731994628906,  /* (0.877 cos 33°)(-0.114)    - (0.492 sin 33°)(1 - 0.114) */
+			   0.21145640212011795888713550084503367543220520019531,  /* (0.877 sin 33°)(1 - 0.299) + (0.492 cos 33°)(-0.299) */
+			  -0.52259104529161115593183239980135113000869750976562,  /* (0.877 sin 33°)(-0.587)    + (0.492 cos 33°)(-0.587) */
+			   0.31113464317149330806699936147197149693965911865234); /* (0.877 sin 33°)(-0.114)    + (0.492 cos 33°)(1 - 0.114) */
+		break;
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp.ciexyz);
+		/* fall through */
+	case LIBCOLOUR_CIEXYZ:
+		TRANSFORM(to->Y, to->I, to->Q, tmp.ciexyz.X, tmp.ciexyz.Y, tmp.ciexyz.Z,
+			   0.40627729168038273499519164033699780702590942382812,
+			   0.61835674212166968910509012857801280915737152099609,
+			  -0.00414330221353725880462093300593551248311996459961,
+			   2.17852787350219845308174626552499830722808837890625,
+			  -1.36502666214454104753883711964590474963188171386719,
+			  -0.64803574634025240541745915834326297044754028320312,
+			   1.20905577682138853923277110880007967352867126464844,
+			  -1.36890364998339797431015085749095305800437927246094,
+			   0.20180559439597040016778350945969577878713607788086);
+		break;
+	}
+}
+
+
+static void
+to_ydbdr(const libcolour_colour_t *restrict from, libcolour_ydbdr_t *restrict to)
+{
+	libcolour_colour_t tmp = *from;
+	switch (from->model) {
+	case LIBCOLOUR_YDBDR:
+		*to = from->ydbdr;
+		break;
+	case LIBCOLOUR_SRGB:
+		if (tmp.srgb.with_transfer) {
+			tmp.srgb.with_transfer = 0;
+			to_srgb(from, &tmp.srgb);
+		}
+		TRANSFORM(to->Y, to->Db, to->Dr, tmp.srgb.R, tmp.srgb.G, tmp.srgb.B,
+			   0.299,  0.587, 0.114,
+			  -0.450, -0.883, 1.333,
+			  -1.333,  1.116, 0.217);
+		break;
+	case LIBCOLOUR_YUV:
+		to->Y  =  tmp.yuv.Y;
+		to->Db =  tmp.yuv.U * D(3.069);
+		to->Dr = -tmp.yuv.V * D(2.169);
+		break;
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp.ciexyz);
+		/* fall through */
+	case LIBCOLOUR_CIEXYZ:
+		TRANSFORM(to->Y, to->Db, to->Dr, tmp.ciexyz.X, tmp.ciexyz.Y, tmp.ciexyz.Z,
+			   0.40627729168038273499519164033699780702590942382812,
+			   0.61835674212166968910509012857801280915737152099609,
+			  -0.00414330221353725880462093300593551248311996459961,
+			  -0.52816561102614745237815441214479506015777587890625,
+			  -1.23677481526212962315014465275453403592109680175781,
+			   1.59692761635924940222253098909277468919754028320312,
+			  -5.38914174974103143966885909321717917919158935546875,
+			   4.09835630362728497999569299281574785709381103515625,
+			   0.94033545560642795013706063400604762136936187744141);
+		break;
+	}
+}
+
+
+static void
+to_yuv(const libcolour_colour_t *restrict from, libcolour_yuv_t *restrict to)
+{
+	libcolour_colour_t tmp = *from;
+	switch (from->model) {
+	case LIBCOLOUR_YUV:
+		*to = from->yuv;
+		break;
+	case LIBCOLOUR_YDBDR:
+		to->Y = from->ydbdr.Y;
+		to->U = from->ydbdr.Db /  D(3.069);
+		to->V = from->ydbdr.Dr / D(-2.169);
+		break;
+	case LIBCOLOUR_SRGB:
+		if (tmp.srgb.with_transfer) {
+			tmp.srgb.with_transfer = 0;
+			to_srgb(from, &tmp.srgb);
+		}
+		TRANSFORM(to->Y, to->U, to->V, tmp.srgb.R, tmp.srgb.G, tmp.srgb.B,
+			   0.29899999999999998800959133404830936342477798461914,
+			   0.58699999999999996624922005139524117112159729003906,
+			   0.11400000000000000410782519111307919956743717193604,
+			  -0.14662756598240470062854967636667424812912940979004,
+			  -0.28771586836102963635752871596196200698614120483398,
+			   0.43434343434343436474165400795754976570606231689453,
+			   0.61456892577224520035628074765554629266262054443359,
+			  -0.51452282157676354490405401520547457039356231689453,
+			  -0.10004610419548178035231700278018251992762088775635);
+		break;
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp.ciexyz);
+		/* fall through */
+	case LIBCOLOUR_CIEXYZ:
+		TRANSFORM(to->Y, to->U, to->V, tmp.ciexyz.X, tmp.ciexyz.Y, tmp.ciexyz.Z,
+			   0.40627729168038273499519164033699780702590942382812,
+			   0.61835674212166968910509012857801280915737152099609,
+			  -0.00414330221353725880462093300593551248311996459961,
+			  -0.17209697328971895746718701047939248383045196533203,
+			  -0.40298951295605395239718404809536878019571304321289,
+			   0.52034135430408912093014350830344483256340026855469,
+			   2.48462044709130047692724474472925066947937011718750,
+			  -1.88951420176453876997868519538315013051033020019531,
+			  -0.43353409663735725798616726933687459677457809448242);
+		break;
+	}
+}
+
+
+static void
+to_ypbpr(const libcolour_colour_t *restrict from, libcolour_ypbpr_t *restrict to)
+{
+	libcolour_colour_t tmp = *from;
+	switch (from->model) {
+	case LIBCOLOUR_YPBPR:
+		*to = from->ypbpr;
+		break;
+	case LIBCOLOUR_SRGB:
+		if (tmp.srgb.with_transfer) {
+			tmp.srgb.with_transfer = 0;
+			to_srgb(from, &tmp.srgb);
+		}
+		to->Y  = tmp.srgb.R * D(0.2126) +
+			 tmp.srgb.G * D(0.7152) +
+			 tmp.srgb.B * D(0.0722);
+		to->Pb = tmp.srgb.B - to->Y;
+		to->Pr = tmp.srgb.R - to->Y;
+		break;
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp.ciexyz);
+		/* fall through */
+	case LIBCOLOUR_CIEXYZ:
+		TRANSFORM(to->Y, to->Pb, to->Pr, tmp.ciexyz.X, tmp.ciexyz.Y, tmp.ciexyz.Z,
+			  -0.00028314209073960778378920011277841695118695497513,
+			   1.00019821310075673892470149439759552478790283203125,
+			   0.00006512054470741990286342115723527967929840087891,
+			   0.05592664565509243568275365987574332393705844879150,
+			  -1.20422439283671711685030913940863683819770812988281,
+			   1.05716144717799576113748116767965257167816162109375,
+			   3.24072939673847715269516811531502753496170043945312,
+			  -2.53733297492083753610359053709544241428375244140625,
+			  -0.49859531356743613805804216099204495549201965332031);
+		break;
+	}
+}
+
+
+static void
+to_ycgco(const libcolour_colour_t *restrict from, libcolour_ycgco_t *restrict to)
+{
+	libcolour_colour_t tmp = *from;
+	switch (from->model) {
+	case LIBCOLOUR_YCGCO:
+		*to = from->ycgco;
+		break;
+	case LIBCOLOUR_SRGB:
+		if (tmp.srgb.with_transfer) {
+			tmp.srgb.with_transfer = 0;
+			to_srgb(from, &tmp.srgb);
+		}
+		to->Y  =  tmp.srgb.R / 4 + tmp.srgb.G / 2 + tmp.srgb.B / 4;
+		to->Cg = -tmp.srgb.R / 4 + tmp.srgb.G / 2 - tmp.srgb.B / 4;
+		to->Co =  tmp.srgb.R / 2 - tmp.srgb.B / 2;
+		break;
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp.ciexyz);
+		/* fall through */
+	case LIBCOLOUR_CIEXYZ:
+		TRANSFORM(to->Y, to->Cg, to->Co, tmp.ciexyz.X, tmp.ciexyz.Y, tmp.ciexyz.Z,
+			   0.33938913643068269188063368346774950623512268066406,
+			   0.50271574450517486631895280879689380526542663574219,
+			   0.16045211478220866574417868832824751734733581542969,
+			  -1.30865574267536244335019546269904822111129760742188,
+			   1.37329621528319534284889869013568386435508728027344,
+			  -0.11889607256777862120955546743061859160661697387695,
+			   1.59240137554169236544510113162687048316001892089844,
+			  -0.66655429104206020962664069884340278804302215576172,
+			  -0.77787838037271606062006412685150280594825744628906);
+		break;
+	}
+}
+
+
+static void
+to_cie1960ucs(const libcolour_colour_t *restrict from, libcolour_cie1960ucs_t *restrict to)
+{
+	libcolour_colour_t tmp = *from;
+	TYPE u, v, w, y;
+	switch (from->model) {
+	case LIBCOLOUR_CIE1960UCS:
+		*to = from->cie1960ucs;
+		return;
+	case LIBCOLOUR_CIEUVW:
+		u = from->cieuvw.U, v = from->cieuvw.V, w = from->cieuvw.W;
+		y = (w + 17) / 25;
+		y *= y * y;
+		w *= 13;
+		to->u = u / w + from->cieuvw.u0;
+		to->v = v / w + from->cieuvw.v0;
+		to->Y = y;
+		return;
+	default:
+		tmp.model = LIBCOLOUR_CIEXYZ;
+		to_ciexyz(from, &tmp.ciexyz);
+		/* fall through */
+	case LIBCOLOUR_CIEXYZ:
+		w = tmp.ciexyz.X + 15 * tmp.ciexyz.Y + 3 * tmp.ciexyz.Z;
+		to->u = 4 * tmp.ciexyz.X / w;
+		to->v = 6 * tmp.ciexyz.Y / w;
+		to->Y = tmp.ciexyz.Y;
+		return;
+	}
+}
+
+
+static void
+to_cieuvw(const libcolour_colour_t *restrict from, libcolour_cieuvw_t *restrict to)
+{
+	TYPE U, V, W, w;
+	libcolour_colour_t tmp = *from;
+	switch (from->model) {
+	case LIBCOLOUR_CIEUVW:
+		U = from->cieuvw.U, V = from->cieuvw.V, W = from->cieuvw.W;
+		w = W * 13;
+		U += w * (from->cieuvw.u0 - to->u0);
+		V += w * (from->cieuvw.v0 - to->v0);
+		to->U = U, to->V = V, to->W = W;
+		break;
+	default:
+		tmp.model = LIBCOLOUR_CIE1960UCS;
+		to_cie1960ucs(from, &tmp.cie1960ucs);
+		/* fall through */
+	case LIBCOLOUR_CIE1960UCS:
+		U = tmp.cie1960ucs.u, V = tmp.cie1960ucs.v, W = tmp.cie1960ucs.Y;
+		W = 25 * xcbrt(W) - 17;
+		w = W * 13;
+		to->U = w * (U - to->u0);
+		to->V = w * (V - to->v0);
+		to->W = W;
+		break;
+	}
+}
+
+
+
+int
+libcolour_convert(const libcolour_colour_t *restrict from, libcolour_colour_t *restrict to)
+{
+#define X(C, T, N) 1 +
+	if (from->model < 0 || from->model > LIST_MODELS(X) 0) {
+#undef X
+		errno = EINVAL;
+		return -1;
+	}
+	switch (to->model) {
+	case LIBCOLOUR_RGB:
+		to_rgb(from, &to->rgb);
+		break;
+	case LIBCOLOUR_SRGB:
+		to_srgb(from, &to->srgb);
+		break;
+	case LIBCOLOUR_CIEXYY:
+		to_ciexyy(from, &to->ciexyy);
+		break;
+	case LIBCOLOUR_CIEXYZ:
+		to_ciexyz(from, &to->ciexyz);
+		break;
+	case LIBCOLOUR_CIELAB:
+		to_cielab(from, &to->cielab);
+		break;
+	case LIBCOLOUR_CIELUV:
+		to_cieluv(from, &to->cieluv);
+		break;
+	case LIBCOLOUR_CIELCHUV:
+		to_cielchuv(from, &to->cielchuv);
+		break;
+	case LIBCOLOUR_YIQ:
+		to_yiq(from, &to->yiq);
+		break;
+	case LIBCOLOUR_YDBDR:
+		to_ydbdr(from, &to->ydbdr);
+		break;
+	case LIBCOLOUR_YUV:
+		to_yuv(from, &to->yuv);
+		break;
+	case LIBCOLOUR_YPBPR:
+		to_ypbpr(from, &to->ypbpr);
+		break;
+	case LIBCOLOUR_YCGCO:
+		to_ycgco(from, &to->ycgco);
+		break;
+	case LIBCOLOUR_CIE1960UCS:
+		to_cie1960ucs(from, &to->cie1960ucs);
+		break;
+	case LIBCOLOUR_CIEUVW:
+		to_cieuvw(from, &to->cieuvw);
+		break;
+	default:
+		errno = EINVAL;
+		return -1;
+	}
+	return 0;
+}