Is there a way to do something every time a variable changes?

[newwaveburritos]

So, I've got a journal in the game, and as you meet and get to know people in the game your "friendship level" so to speak increases.  Well, after scripting quite a few I realized it would be a good idea to give the player some feedback that something in their journal has changed so I had the idea to play a sound.  I could search through and find every instance of "ChefRomanFriendshipPoints++;" et al but I think it might be easier to have a couple of lines of code that plays the sound when anything changes.

I have a hunch that someone is going to tell me that this is exactly what for loops are for and how come I haven't actually learned how to use them yet.

Thanks again, everybody!!

[Khris]

Sorry, no for loops

It gets worse: you have to search and replace all those  ChefRomanFriendshipPoints++;  lines. You cannot detect a change in a variable, but since you are the one making it, you can call a function instead:

Code: ags

function FriendshipChefRoman(int change) {
  ChefRomanFriendshipPoints  = change;
  aFriendshipincrease.Play();
}

You then call  FriendshipChefRoman(1);  to add one to the value and also play the sound.

Using the full capabilities of AGS you can of course change this to

Code: ags

function ChangeNPCLevel(Character *npc, eLevel level, int by) {
  levels[npc.ID].value[level]  = by;
  if (by > 0) aLevelincrease.Play();
  else aLeveldecrease.Play();
}

This requires some more setup of course (a struct to store the levels and an enum containing  eLevelFriendship  etc.)

[newwaveburritos]

Okay, this makes sense.  I'm not super clear on using structs to keep everything organized although, in theory, it does make sense.  I've just been using the journal itself to track it when testing.  I do have kind of a lot of characters to track so maybe I should try this.

[Khris]

Here's the full code:

Code: ags

// header
enum Stat {
  eFriendship, eLove
};

struct CharStat {
  int level[3]; // amount of stats
};

import void ChangeLevel(this Character*, Stat stat, by = 1);

Code: ags

CharStat stats[30]; // highest ID if NPC + 1

void ChangeLevel(this Character*, Stat stat, int by) {
  stats[this.ID].level[stat] += by;
  if (by > 0) aLevelincrease.Play();
  if (by < 0) aLeveldecrease.Play();
}

Call it like:

Code: ags

  cChefRoman.ChangeLevel(eFriendship);  // default change: +1

[newwaveburritos]

Oh, thanks!  I'm sure this will come in useful.  It's a real learning experience, too.