Open FlowerAging.gsz.

As you know flowers do not stay on the plant for a long time after blooming; in fact, they perish rather quickly and are dropped altogether or are replaced by a growing fruit after successful pollination. In our model, we can very simply introduce aging and dropping of flowers. First, the Flower requires two new parameters, age and max_age (L. 20):

module Flower(int age, int max_age)  ==> //insert two new parameters for Flower
RU(180) Cone(0.3, 0.3).(setShader(internodemat))  ...

When the Flower is introduced in the run method for the first time it is initiated like this:

Bud(r, p, o), (r == 10) ==> RV(-0.1) Internode(0.05, 1) RV(-0.1) Internode(0.05, 1) Flower(1, irandom(10, 15)); 
...

The initial age is thus 1, whereas the maximum age that the flower can attain is between 10 and 15 days, as determined by this command, irandom(10, 15), which will draw a number between 10 and 15, with equal probability.

As long as age has not attained max_age, it is incremented by one, i.e. the flower ages:

//increment flower age as long as max age is not reached:
Flower(t, m), (t<m) ==> Flower(t+1, m);

When age is equal to max_age the flower is dropped:

//shed flower when max age is reached:
Flower(t,m), (t>=m) ==>  ;

Next, we could let the flower be transformed into a fruit (module already declared), with a certain probability, instead of letting it die: In order for this to work you need to write instead of

//shed flower when max age is reached:
Flower(t,m), (t>=m) ==>  ;

this:

//shed flower when max age is reached:
//Flower(t,m), (t>=m) ==>  ;
Flower(t,m), (t>=m) ==>  if(probability(0.5)) (Fruit) ;

Task: Introduce leaf shedding after 20 steps!