On 9/1/2021 1:08 PM, Jairo A. del Rio via ntg-context wrote:
Hi, list!
I want to know if there's a handy way to pass predefined colors, either
RGB or CMYK, e.g. those in svg or crayola, to Metafun's bitmapimage.
Say, something like:
\startMPpage
% svg's gold definition
draw bitmapimage(2, 2, "ffd700 ffd700 ffd700 00") scaled 3cm;
\stopMPpage
using "gold" instead of its definition so that I can set bitmap image
colors by name rather than numbers. In a similar vein, I wonder if
something analogous is possible for ConTeXt's \bitmapimage macro. Thank
you in advance.
it's mostly about 'what interface to use' and 'how is that documented
and remembered at all'
\startluacode
function MP.replacecolors(str,c)
-- could be a helper, these two combined (never needed it):
local m, a = attributes.colors.namedcolorattributes(c)
local d = attributes.colors.values[a]
local r = string.format("%02x%02x%02x",
math.round(d[3]*255),
math.round(d[4]*255),
math.round(d[5]*255)
)
mp.quoted((string.gsub(str,"44",r)))
end
\stopluacode
\definecolor[kindofgold][h=ffd700]
\startMPpage
draw bitmapimage(2, 2, "ffd700 ffd700 ffd700 00") scaled 3cm;
vardef mybitmapimage(expr n, m, s, c) =
bitmapimage(2, 2, MP.replacecolors(s, c))
enddef ;
draw mybitmapimage(2, 2, "44 44 44 00", "kindofgold")
scaled 3cm shifted (0,-3cm);
\stopMPpage
-
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
___
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl / http://context.aanhet.net
archive : https://bitbucket.org/phg/context-mirror/commits/
wiki : http://contextgarden.net
___
