MetaFun - Pragma ADE

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draw hlingrid(0, 10, 1, 3cm, 3cm) slanted .5 ;
draw vlingrid(0, 10, 1, 3cm, 3cm) slanted .5 ;
Using macros like these often involves a bit of trial and error. The arguments to these macros are
as follows:
hlingrid (Min, Max, Step, Length, Width)
vlingrid (Min, Max, Step, Length, Height)
hloggrid (Min, Max, Step, Length, Width)
vloggrid (Min, Max, Step, Length, Height)
The macros take the following text upto the semi--colon into account and return a picture. We will
now apply this knowledge to a more meaningful example. First we draw a grid.
You can use the grid drawing macros to produce your own paper, for instance using the following
mixed TEX--METAFUN code:
\startMPpage
StartPage ;
width := PaperWidth ; height := PaperHeight ; unit := cm ;
drawoptions(withpen pencircle scaled .2pt withcolor .8white) ;
draw vlingrid(0, width /unit, 1/10, width, height) ;
draw hlingrid(0, height/unit, 1/10, height, width ) ;
drawoptions(withpen pencircle scaled .5pt withcolor .4white) ;
draw vlingrid(0, width /unit, 1, width, height) ;
draw hlingrid(0, height/unit, 1, height, width ) ;
StopPage ;
\stopMPpage
This produces a page (as in figure 9.1) with a metric grid. If you're hooked to the inch, you can
set unit := 1in. If you want to process this code, you need to wrap it into the normal document
producing commands:
\setupoutput[pdftex]
\setupcolors[state=start]
\starttext
... definitions ...
\stoptext
Functions Grids