Re: [NTG-context] METAPOST/MetaFun withtransparency doesn't accept my pair primary argument, what am I doing wrong?
As I only use one transparency method anyway I could also fix this by passing a numeric instead of a pair and use the standard withtransparency (I don’t like overriding a standard MetaFun method, one never knows what might break in future updates). vardef Foo( expr w, h, fillColor, fillTransparency) = show "FOO:", w, h, fillColor, fillTransparency; save pic; picture pic; save circ; path circ; circ := (fullcircle xyscaled (h,h)); pic := image ( fill (circ shifted (w-h/2,-h/2)) withcolor fillColor withtransparency (1,fillTransparency); ); pic enddef; picture pic; pic := Foo( 150, 50, (0.686,1.000,1.000), 0.5); draw pic; \stopMPpage \stoptext > On 9 Apr 2020, at 18:06, Hans Hagen wrote: > > On 4/9/2020 4:58 PM, Gerben Wierda wrote: >> \starttext >> \startMPpage[instance=doublefun] >> vardef Foo( expr w, h, fillColor, fillTransparency) = >> show "FOO:", w, h, fillColor, fillTransparency; >> save pic; picture pic; >> save circ; path circ; >> circ := (fullcircle xyscaled (h,h)); >> pic := image ( >> fill (circ shifted (w-h/2,-h/2)) withcolor fillColor withtransparency >> fillTransparency; >> ); >> pic >> enddef; >> pic := Foo( 150, 50, (0.686,1.000,1.000), (1,1.000)); >> draw pic; >> \stopMPpage >> \stoptext > > Maybe this definition is better then but I need to test it more > > \starttext > \startMPpage[instance=doublefun] > > def withtransparency expr t = >if pair t : >withprescript "tr_alternative=" & decimal > transparency_alternative_to_number(xpart t) >withprescript "tr_transparency=" & decimal ypart t >else : >mfun_with_transparency (transparency_alternative_to_number(t)) >fi > enddef ; > > def mfun_with_transparency (expr a) expr t = >withprescript "tr_alternative=" & decimal a >withprescript "tr_transparency=" & decimal t > enddef ; > > vardef Foo ( expr w, h, fillColor, fillTransparency) = > image ( >fill fullcircle xyscaled (h,h) shifted (w-h/2,-h/2) >withcolor fillColor >withtransparency fillTransparency >; > ) > enddef; > > vardef FooX ( expr w, h, fillColor) = > image ( >fill fullcircle xyscaled (h,h) shifted (w-h/2,-h/2) >withcolor fillColor >withtransparency (normaltransparent, .5) >; > ) > enddef; > > vardef FooY ( expr w, h, fillColor) = > image ( >fill fullcircle xyscaled (h,h) shifted (w-h/2,-h/2) >withcolor fillColor >withtransparency normaltransparent .5 >; > ) > enddef; > > draw Foo ( 350, 50, (0.5,1,0), (1,.5)); > draw FooX ( 250, 50, (1,0.5,1)); > draw FooY ( 150, 50, (1,1,0.5)); > > \stopMPpage > \stoptext > > > -- > > - > 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 ___
Re: [NTG-context] METAPOST/MetaFun withtransparency doesn't accept my pair primary argument, what am I doing wrong?
On 4/9/2020 4:58 PM, Gerben Wierda wrote: \starttext \startMPpage[instance=doublefun] vardef Foo( expr w, h, fillColor, fillTransparency) = show "FOO:", w, h, fillColor, fillTransparency; save pic; picture pic; save circ; path circ; circ := (fullcircle xyscaled (h,h)); pic := image ( fill (circ shifted (w-h/2,-h/2)) withcolor fillColor withtransparency fillTransparency; ); pic enddef; pic := Foo( 150, 50, (0.686,1.000,1.000), (1,1.000)); draw pic; \stopMPpage \stoptext Maybe this definition is better then but I need to test it more \starttext \startMPpage[instance=doublefun] def withtransparency expr t = if pair t : withprescript "tr_alternative=" & decimal transparency_alternative_to_number(xpart t) withprescript "tr_transparency=" & decimal ypart t else : mfun_with_transparency (transparency_alternative_to_number(t)) fi enddef ; def mfun_with_transparency (expr a) expr t = withprescript "tr_alternative=" & decimal a withprescript "tr_transparency=" & decimal t enddef ; vardef Foo ( expr w, h, fillColor, fillTransparency) = image ( fill fullcircle xyscaled (h,h) shifted (w-h/2,-h/2) withcolor fillColor withtransparency fillTransparency ; ) enddef; vardef FooX ( expr w, h, fillColor) = image ( fill fullcircle xyscaled (h,h) shifted (w-h/2,-h/2) withcolor fillColor withtransparency (normaltransparent, .5) ; ) enddef; vardef FooY ( expr w, h, fillColor) = image ( fill fullcircle xyscaled (h,h) shifted (w-h/2,-h/2) withcolor fillColor withtransparency normaltransparent .5 ; ) enddef; draw Foo ( 350, 50, (0.5,1,0), (1,.5)); draw FooX ( 250, 50, (1,0.5,1)); draw FooY ( 150, 50, (1,1,0.5)); \stopMPpage \stoptext -- - 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 ___
[NTG-context] METAPOST/MetaFun withtransparency doesn't accept my pair primary argument, what am I doing wrong?
I have refactored my code to use withtransparency and separate parameters for colors, sizes, transparency, etc. But I’m running into a problem. The fillTransparency parameter is a pair primary (as can be seen from the show command) Here is a pretty minimum example (in reality there are multiple colors and transparencies passed on): \starttext \startMPpage[instance=doublefun] vardef Foo( expr w, h, fillColor, fillTransparency) = show "FOO:", w, h, fillColor, fillTransparency; save pic; picture pic; save circ; path circ; circ := (fullcircle xyscaled (h,h)); pic := image ( fill (circ shifted (w-h/2,-h/2)) withcolor fillColor withtransparency fillTransparency; ); pic enddef; pic := Foo( 150, 50, (0.686,1.000,1.000), (1,1.000)); draw pic; \stopMPpage \stoptext and the result is: metapost log> >> "FOO:" metapost log> >> 150 metapost log> >> 50 metapost log> >> (0.68605,1,1) metapost log> >> (1,1) metapost log> ! Missing argument to withtransparency. metapost log> metapost log>((1,1)) metapost log> ...005,1,1))withtransparency((1,1)) metapost log> ; metapost log> image->...ture;currentpicture:=nullpicture;(TEXT3) metapost log> ;currentpicture.if.str(SUF... metapost log> metapost log> Foo->...)withcolor(EXPR4)withtransparency(EXPR5);) metapost log> ;pic.endgroup metapost log> <*> ...o( 150, 50, (0.686,1.000,1.000), (1,1.000)) metapost log> ; draw pic; ; What am I doing wrong here? Thanks, G PS. Given the complaint about asking both here and on tex.stackexchange, which of the two is the best place?___ 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 ___
