I tried to use scripts to create a synthesis shop in my game, but every error ever popped up when i tried, so i decided to make one using events, it's not perfect, and it's probably obvious to most people, but I wanted to help if I could.
Ok so first make an event square, can be anything, from a chest to a dead bird.
Then think of something you would synthesize, my examples are hi-potions and bronze swords. Next you need to think of the ingredients, and whether you want to charge your players for the service. For a bronze sword i used 1 bronze bar and 10g, the bronze bar is an item i needed to make myself (as I'm sure you're aware).
Then go to the event, and you need to make the event go to some sort of menu, i've kept all of mine in the message box.
As you can see the even is unfinished, but it is tested.
To keep this in the message box, I i kept it all based on choices, the first being "synthesize or no?" after I chose which category, weapons or armor, I kept it to this because I am located this in a weapons shop, I plan to add an alchemist to the inn. In this event I went down one path, but it shows all options clearly, after the categories, we place items in it, again through choices, mine reads "Bronze sword, Bronze knife, Bronze spear, Leave"
since you can only have 4 choices at once, you must either limit the amount each person can make, or add extra pages, in which case you would replace "Leave" with "Next page", in having a next page, this does bring up other difficulties, such as "do I have items, and scroll through every page to exit, or two items per page and be able to leave?" this is entirely up to you.
Now say you want to know what you need to make an item and choose if its worth it before making it? Easy, again through choices, after the bronze sword is chosen set up some text, e.g. "1 bronze bar and 10g needed to make this, continue?" and then another choice "yes/no" after yes we need a conditional branch, this will check if we have the items before it just makes it for us, so select conditional and go to page 4, items, bronze bar and select 1 needed. after that we need to check if we have enough gold or not, so another conditional branch underneath the "yes" section of the previous branch, page 4, gold, 10 needed.
under the no sections of those branches a simple "not enough [insert item name here]" message should suffice.
Then after those we have events to take the money and item out and place the sword in.
I hope this helps at least one person, as I found it hard to have a working creation system in my game.
screenshots of working event:
[edit]---I have just noticed that it doesn't allow for 2 or more of the same item to be required, I am working on that now though.
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