While shading works with MkIV, with LMTX the following breaks:

\startMPpage

comment("two shades with named colors");

fill fullcircle scaled 5cm

withshademethod "circular"

withshadecolors ((1,0,0),(0,0,1,0))

;

fill fullcircle scaled 5cm shifted (6cm,0)

withshademethod "circular"

withcolor (1,0,0,0) shadedinto "blue"

;

\stopMPpage

The log says:

metafun > log >

metafun > log > error: Unknown relation will be considered false

metafun > log >

metapost > log >

metapost > log > <to be read again>

metapost > log > :

metapost > log > <for(100.21985)> if(EXPR0)>temp_any_u:

metapost > log > temp_any_u:=(EXPR0);fi ENDFOR

metapost > log > max->begingroup.save.temp_any_u;if.pair(EXPR2):pair.temp_any_u.elseif.string(EXPR2):string.temp_any_u.fi;temp_any_u=(EXPR2)for.i=(TEXT3):if.i>temp_any_u:temp_any_u:=i;fi.endfor

metapost > log > .temp_any_u.endgroup

metapost > log > mfun_max_radius->...er(EXPR2)-xpart.center(EXPR2))++(ypart.center(EXPR2)-ypart.lrcorner(EXPR2)),(xpart.urcorner(EXPR2)-xpart.center(EXPR2))++(ypart.urcorner(EXPR2)-ypart.center(EXPR2)))

metapost > log > endgroup

metapost > log > withshademethod->...cimal.center(EXPR0)withprescript"sh_center_b="&ddecimal.center(EXPR0)withprescript"sh_radius_a="&decimal0withprescript"sh_radius_b="&decimal.mfun_max_radius((EXPR0))

metapost > log > fi

metapost > log > <to be read again>

metapost > log > withprescript

metapost > log > withshadecolors->...hprescript"sh_color_a_"&decimal.mfun_shade_step&"="&colordecimals(EXPR0)withprescript"sh_color_b_"&decimal.mfun_shade_step&"="&colordecimals(EXPR1)else:withprescript

metapost > log > "sh_color=in...

metapost > log > <*> comment("two shades with named colors"); fill fullcircle scaled 5cm withshademethod "circular" withshadecolors ((1,0,0),(0,0,1,0))

metafun > log >

metafun > log > Oh dear. I can't decide if the expression above is positive, negative, or zero.

So this comparison test won't be 'true'.

metafun > log >

metapost > log > ; fill fullcircle scaled 5cm shifted (6cm,0) withshademethod "...

metapost > log >

Hans told me not to use the B tag, so I'm asking first in case I've missed something. Thank you in advance.

Best regards,

Jairo