blob: e161cac5b324402dc61bff9ddad666e6ec5bb130 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
#N canvas 6 61 602 259 10;
#X declare -lib Gem;
#X obj 14 66 gemwin;
#X obj 14 9 tgl 15 0 empty empty empty 17 7 0 10 -262144 -1 -1 0 1
;
#X msg 48 10 create;
#X msg 55 33 destroy;
#X obj 14 93 gemhead;
#X obj 14 153 t a a;
#X obj 59 153 circle;
#X obj 14 223 scale 0.7;
#X obj 14 183 rotate 45 0 0 1;
#X obj 14 203 translate 2 0 1 0;
#X text 170 17 A tutorial on recursion in Gem;
#X text 170 37 (GPL) 2007 Claude Heiland-Allen <claude@mathr.co.uk>
;
#X text 170 77 A common idiom in Gem is to use the [repeat] object
found in the Zexy library \, to generate multiple copies of the same
object. Let's try using it to make our spiral.;
#X obj 14 123 repeat 64;
#X text 170 127 And indeed \, it works well. But a spiral is a linear
structure \, without branches. Iteration has solved one problem \,
only to present us with another: what if we want a branching structure?
;
#X text 170 187 Recursion is an elegant solution to this problem.;
#X obj 470 9 declare -lib Gem;
#X connect 1 0 0 0;
#X connect 2 0 0 0;
#X connect 3 0 0 0;
#X connect 4 0 13 0;
#X connect 5 0 8 0;
#X connect 5 1 6 0;
#X connect 8 0 9 0;
#X connect 9 0 7 0;
#X connect 13 0 5 0;
|
