MetaFun - Pragma ADE

1.15 Text
Most dashpatterns can be defined in terms of on and off. This simple on--off dashpattern is predefined
as picture evenly. Because this is a picture, you can (and often need to) scale it.
draw (0,0)--(10cm,0) dashed (evenly scaled 1mm)
withpen pencircle scaled 1mm ;
Opposite to a defaultpen, there is no default color and default dash pattern set. The macro
drawoptions provides you a way to set the default attributes.
drawoptions(dashed evenly withcolor red) ;
Since METAFONT is meant for designing fonts, the only means for including text are those that permit
you to add labels to positions for the sole purpose of documentation.
Because METAPOST is derived from METAFONT it provides labels too, but in order to let users add
more sophisticated text, like a math formula, to a graphic, it also provides an interface to TEX.
Because we will spend a whole chapter on using text in METAPOST we limit the discussion here to
a few fundamentals.
pair a ; a := (3cm,3cm) ;
label.top("top",a) ; label.bot("bot",a) ;
label.lft("lft",a) ; label.rt ("rt" ,a) ;
These four labels show up at the position stored in the pair variable a, anchored in the way specified
after the period.
top
lft rt
bot
The command dotlabel also typesets the point as rather visible dot.
pair a ; a := (3cm,3cm) ;
dotlabel.top("top",a) ; dotlabel.bot("bot",a) ;
dotlabel.lft("lft",a) ; dotlabel.rt ("rt" ,a) ;
top
lft rt
bot
The command thelabel returns the typeset label as picture that you can manipulate or draw
afterwards.
pair a ; a := (3cm,3cm) ; pickup pencircle scaled 1mm ;
drawdot a withcolor .625yellow ;
draw thelabel.rt("the right way",a) withcolor .625red ;
Text Welcome to MetaPost
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