Best to use self.object or create local object ?

anneMurielle

There is something that I'm not really sure...

Could you tell me what it's better to user or what should be avoid ? If I want to create an object that I could use during some time in the application (some click activity or animation or set visibility later or remove it ), is it correct to create it as self.something ? Or it is better to create a global object in a lua page (local something) ?

Thanks

OZApps

You can get different response to this one, however in my opinion here's how I look at it.

local tempObj = self.Object print(tempObject)

then using tempObj is one opcode in LuaVM whereas,

print(self.Object)

is equivalent of two opcodes, one to first get the global to get self and then to get object.

If there were a couple of lines that would require access to self.Object, that would be slightly more intensive (if you are looking for critical and optimisation) otherwise it should not matter much really.

Secondly, if you are going to encapsulate everything then fine, otherwise you would need some place to save the objects (animation, etc) which would ultimately need to be global. So you can access it by assigning it to a local variable for that function.

To back this

local object = self.object object = object + 1 object = object * 3 print(object)

Translates to the following

getglobal 0 0 ; self gettable 0 0 257 ; "object" add 0 0 258 ; 1 mul 0 0 259 ; 3 getglobal 1 4 ; print move 2 0 call 1 2 1

and then

self.object = self.object + 1 self.object = self.object * 3 print(self.object)

would on the other hand translate to

getglobal 0 0 ; self getglobal 1 0 ; self gettable 1 1 257 ; "object" add 1 1 258 ; 1 settable 0 257 1 ; "object" getglobal 0 0 ; self getglobal 1 0 ; self gettable 1 1 257 ; "object" mul 1 1 259 ; 3 settable 0 257 1 ; "object" getglobal 0 4 ; print getglobal 1 0 ; self gettable 1 1 257 ; "object" call 0 2 1

as you can see that each time we use

self.object

that first gets the global self, then gets the table sub-item "object" while when we use local, it doesn't have to access the global table and sub item.

anneMurielle

Thank you a lot for your explanation!

GregBUG

@OZApps
nice!
thanks!