## Binding two objects

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Lirija
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### Binding two objects

I'm sorry that i did't found a better way to explain this:
i'd like to have some objects work "in tandem" such as a switch that when triggered opens a particular gate or two tiles that teleport the player from one to another, do you have any suggestion on how i can accomplish this?
Last edited by Lirija on Tue Apr 17, 2018 11:31 am, edited 1 time in total.
Beelz
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Location: New York, USA
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### Re: Make two objects "work together"

Code: Select all

function newDoor(x, y)
return {
x = x or 0,
y = y or 0,
closed = true,

interact = function() closed = not closed end
}
end

-- Then you can place them, for simplicity we'll pretend x and y are tile locations
local doors = {}

for i = 1, 10 do
table.insert(doors, newDoor(math.random(1, 10), math.random(1, 10)))
end

Then make the triggers for the player to step on.

Code: Select all

function newTrigger(x, y, door)
return {
x = x or 0,
y = y or 0,
door = door or nil,

interact = function()
if door then door:interact() end
end
}
end

local triggers = {}

for i = 1, 3 do
table.insert(triggers, newTrigger(math.random(1, 10), math.random(1, 10), doors[math.random(1, #doors)])
end

Whenever the player moves loop over the list of triggers to see if they're on one. If they are, invoke the interaction.

Code: Select all

for i, v ipairs(triggers) do
if player.x == v.x and player.y == v.y then
v.interact()
return
end
end


Code: Select all

if self:hasBeer() then self:drink()
else self:getBeer() end

GitHub -- Website
Lirija
Prole
Posts: 28
Joined: Tue Mar 14, 2017 11:42 am
Contact:

### Re: Make two objects "work together"

Thank you! Your explanation was crystal clear!
Just another question: if i want to place the interacting objects using tiled and i have more than one pair in the same map how could i bind them correctly? (the only thing i can think of is give them a name like "object door 1" and using string patterns methods later to assign the door to the corresponding switch)
Beelz
Party member
Posts: 234
Joined: Thu Sep 24, 2015 1:05 pm
Location: New York, USA
Contact:

### Re: Binding two objects

Maybe someone else can be more help here... I haven't used Tiled much other than a making static map. The code I provided won't throw an error if the player steps on a trigger that isn't connected to a door. The trick is to pass the door reference to the trigger, then the trigger interacts with the specific door directly. One way or another Tiled won't be able to do everything, and you'll have to link them together eventually. Then again take this with a grain of salt, because as I said, I'm not very experienced with Tiled.

Code: Select all

if self:hasBeer() then self:drink()
else self:getBeer() end

GitHub -- Website

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