From 40e6ef1f99f78e80af9658b7c600f1f669f6bba3 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Sat, 17 Dec 2016 16:28:23 +0100 Subject: CIELChuv: measure hue in degrees, but add parameter to change this MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- doc/info/chap/colour-spaces.texinfo | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'doc/info/chap') diff --git a/doc/info/chap/colour-spaces.texinfo b/doc/info/chap/colour-spaces.texinfo index a214feb..9455bbc 100644 --- a/doc/info/chap/colour-spaces.texinfo +++ b/doc/info/chap/colour-spaces.texinfo @@ -354,7 +354,7 @@ The wide-gamut RGB colour space, also known as Adobe Wide Gamut RGB. @end table -Call @code{libcolour_proper(&c)} on a +The call @code{libcolour_proper(&c)} on a @code{struct libcolour_rgb_t c} (done automatically for predefined colour spaces) sets @code{c.red.model}, @code{c.green.model}, and @code{c.blue.model} to @@ -521,7 +521,7 @@ The white point. CIE L*u*v* is not additive, since conversion from CIE 1931 XYZ is non-linear. -Call @code{libcolour_proper(&c)} on a +The call @code{libcolour_proper(&c)} on a @code{struct libcolour_cieluv_t c} sets @code{c.white.model} to @code{LIBCOLOUR_CIEXYZ}. Zero is always returned in this case. @@ -555,15 +555,20 @@ The C*@sub{uv} value, the chroma. The h@sub{uv} value, the hue. @item struct libcolour_ciexyz white The white point. +@item double one_revolution +The value lowest positive values of @code{h} that is equivalent to 0. +360 if the hue is measured in degrees, 400 if the hue is measured in +gon, and 2 pi if the hue is measured radian. Any value can be used. @end table CIE LCh@sub{uv} is not additive. It is a cylindrical representation of CIE 1976 (L*, u*, v*). -Call @code{libcolour_proper(&c)} on a +The call @code{libcolour_proper(&c)} on a @code{struct libcolour_cielchuv_t c} sets -@code{c.white.model} to @code{LIBCOLOUR_CIEXYZ}. -Zero is always returned in this case. +@code{c.white.model} to @code{LIBCOLOUR_CIEXYZ}, +and if @code{c.one_revolution} is 0, it is set +to 360. Zero is always returned in this case. @node YIQ -- cgit v1.2.3-70-g09d2