[Therion] area file defs

[Georg Pacher]

  On 16.09.2010 09:46, Andrew Atkinson wrote:


Hi!

> Thanks for the examples of code you have put on the wiki, it is 
> helping me lots with my first play at altering the code. I have moved 
> onto playing with the area defs.
>

I would recommend you to check out the included symbol definitions as 
well, by downloading the therion source code. There in the directory 
/therion/mpost you find all the symbol definitions. In the a_blocks_AUT 
definition (in file uAUT.mp, only included since 5.3.3) you can change 
the values for symbol_distance and scale_factor to achieve what you want...

Here's your code with two parameters, to change the distance between 
blocks and the scale of the blocks:

        def a_blocks_AMER (expr p) =
       T:=identity;
       pickup PenC;
       path q, qq; q = bbox p;
       picture tmp_pic;
       symbol_distance:= 1.0;
       scale_factor:= 1.0;
       tmp_pic := image(
         for i = xpart llcorner q step u*symbol_distance until xpart 
urcorner q:
          for j = ypart llcorner q step u*symbol_distance until ypart 
urcorner q:
             qq := punked
   (((-.2u,-.2u)--(.2u,-.2u)--(.2u,.2u)--(-.2u,.2u)--cycle)
          randomized (u/2))
           scaled scale_factor
                rotated uniformdeviate(360)
                shifted ((i,j) randomized u);
        if xpart (p intersectiontimes qq) < 0:
         thclean qq;
         thdraw qq;
        fi;
           endfor;
         endfor;
       );
       clip tmp_pic to p;
       draw tmp_pic;
     enddef;



However, you have to be careful not to run into memory problems with 
metapost when drawing lots of small blocks. That's why the a_blocks_AUT 
defintion has some more code. It reduces the number of blocks which are 
drawn and clipped afterwards.

> Andrew

Georg.