diff options
Diffstat (limited to 'doc/context/sources/general/manuals/metafun/metafun-welcome.tex')
| -rw-r--r-- | doc/context/sources/general/manuals/metafun/metafun-welcome.tex | 52 |
1 files changed, 51 insertions, 1 deletions
diff --git a/doc/context/sources/general/manuals/metafun/metafun-welcome.tex b/doc/context/sources/general/manuals/metafun/metafun-welcome.tex index a7b1715a7..90ceab730 100644 --- a/doc/context/sources/general/manuals/metafun/metafun-welcome.tex +++ b/doc/context/sources/general/manuals/metafun/metafun-welcome.tex @@ -2181,6 +2181,56 @@ The macro \type {drawoptions} provides you a way to set the default attributes. drawoptions(dashed evenly withcolor red) ; \stoptyping +Dashes are pretty much bound to the backend in the sense that like line width +they are a property that the \POSTSCRIPT\ (or actually nowadays the \PDF) +interpreter handles. There is not that much cleverness involved at the \METAPOST\ +end. Take these examples: + +\startbuffer + pickup pencircle scaled 2mm ; path p ; + + p := (0,0) {dir 25} .. (5cm,0) ; + draw p withcolor darkyellow ; + draw p dashed dashpattern (on 4mm off 3mm) withcolor darkblue ; + drawpoints point 0 of p withcolor white ; + + p := ((0,0) {dir 70} .. {up} (5cm,0) .. cycle) yshifted -1cm ; + draw p withcolor darkyellow ; + draw p dashed dashpattern (on 4mm off 3mm) withcolor darkblue ; + drawpoints point 0 of p withcolor white ; +\stopbuffer + +\typebuffer[a] + +\startlinecorrection[blank] +\processMPbuffer +\stoplinecorrection + +In both cases the dash is not evenly spread which for the line results in +different begin and end rendering while the closed shape gets some weird looking +connection. The next variant uses the \type {withdashes} macro that adapts the +dashes to fit nicely to the path. + +\startbuffer[a] + pickup pencircle scaled 2mm ; path p ; + + p := (0,0) {dir 25} .. (5cm,0) ; + draw p withcolor darkyellow ; + draw p withdashes (4mm,3mm) withcolor darkblue ; + drawpoints point 0 of p withcolor white ; + + p := ((0,0) {dir 70} .. {up} (5cm,0) .. cycle) yshifted -1cm ; + draw p withcolor darkyellow ; + draw p withdashes (4mm,3mm) withcolor darkblue ; + drawpoints point 0 of p withcolor white ; +\stopbuffer + +\typebuffer + +\startlinecorrection[blank] +\processMPbuffer +\stoplinecorrection + \stopsection \startsection[reference=sec:text,title={Text}] @@ -3164,7 +3214,7 @@ following line: \startbuffer[b] redraw currentpicture withpen pencircle scaled 2pt ; -draw boundingbox currenpicture withpen pencircle scaled .5mm ; +draw boundingbox currentpicture withpen pencircle scaled .5mm ; \stopbuffer \typebuffer[b] |