Accessing an Emitter interface in LUA script problem

[Rozen Software]

I have created an entity with one emitter child object. I try to access its interface with the code:

 

local emitter = self.entity:GetChild(0)
emitter:Reset()

 

Unfortunately Reset method is not executed and a nil value is thrown.

Does someone know how to correctly access an Emitter interface from LUA script in such situation? Is this possible?

 

Thanks,

Piotr

 

(Leadwerks 3.5 beta branch, Standard Edition)

[macklebee]

Works fine for me. Are you sure that the emitter is the only child? I suggest performing an entity:CountChildren() to confirm.

example code:

function Script:UpdateWorld()
 local window = Window:GetCurrent()
 if window:KeyHit(Key.Up) then
   local emitter = self.entity:GetChild(0)
   emitter:Reset()
   emitter:SetColor(math.random(0,255)/255,math.random(0,255)/255,math.random(0,255)/255,1)
 end
end

 

Also, remember there are several ways to access the emitter. You could use entity:FindChild() to search for the emitter's specific name. Or make it a script entity property in the property panel and drag the emitter to the textbox.

[Rozen Software]

Yes, I checked it out and entity:GetCountChildren() returned 1.

 

In my case this entity (your chamferbox) is a prefab and loaded dynamically.

 

I did workaround it by attaching a script to the emitter entity:

 

function Script:Reset()
self.entity:Reset()
self.entity:Play()
end

 

 

and invoking it:

 

self.emitter = self.entity:GetChild(0)
self.emitter.script:Reset()

 

That's works ...

[macklebee]

Ah - ok... you are loading it dynamically - that information you left out in the OP. Then in that case you have to cast the emitter to the Emitter class. It's probably best to get in the habit (myself included) to cast special entities after using GetChild or FindChild.

 

 

This example works now even when the chamfer box is loaded dynamically via code:

function Script:UpdateWorld()
 local window = Window:GetCurrent()
 if window:KeyHit(Key.Up) then
   local emitter = self.entity:GetChild(0)
   tolua.cast(emitter, "Emitter")
   emitter:Reset()
   emitter:SetColor(math.random(0,255)/255,math.random(0,255)/255,math.random(0,255)/255,1)
 end
end