Selecting something by its ID

[Game_Master]

Hi
I have 12 Active Picture objects, each of them is a clone of the first one. They are all in a qualifier group called "Neutral" and they each have an alterable value named "ID". How would I get it so that I could select in a loop an object from the value of it's ID?

Thanks,
GM

[Pixelthief]

You'd want to assign each one an ID in its alterable values instead of using its 'fixed value', since those are nondeterministic. After creating them all, for example at the start of the frame, you'd want to put a line:

-Spread Value 0 in Active Picture

This will assign a value to each active picture, starting with 0 and incrementing by 1 on each one (ie 0, 1, 2, 3, ... 11)


In your loop code, to select one object, you'd simply add the condition:


+Does Alterable Value of Active Picture == LoopIndex("Fast Loop Name")



An alternative, and more robust way of 'selecting one object from a group in a loop' is using 2 flags to select objects. This same skeleton code can be used in any part of your code for any object, without having it be set up via spread values first:

+Upon Condition XXXXX
=Set Flag 1 of "Object" OFF
=Set Flag 2 of "Object" OFF
=Start Fast Loop "Loop" for NumObjects("Object") number of times.

+Upon Fast Loop "Loop"
+"Object" Flag 1 is OFF
+Pick an "Object" at random
=Set Flag 1 of "Object" ON
=Set Flag 2 of "Object" ON

+Upon Fast Loop "Loop"
+"Object" Flag 2 is ON
=DO YOUR ACTIONS HERE

+Upon Fast Loop "Loop"
=Set Flag 2 of "Object" OFF

This will select one object at a time from a group, run the events on it, and then pick another on the next iteration, never picking the same one twice. However, be warned that in large applications this uses O(N^2) time complexity for N objects, since there are N loops each with N comparisons to flags (each flag comparison has to iterate over N objects), so while this is suitable for 12 objects, it wouldn't be for 1200.

[Game_Master]

Thanks, I appreciate the reply, but since the objects are cloned, this doesn't work

[Pixelthief]

You mean they are separate objects?
You'd have to select each one individually, with one line of code per object, which is why its not a good idea to clone everything :S

[Game_Master]

The reason I cloned them is because they had to have seperate alterable values/strings (each one has an icon path, icon image, tooltip etc). Would the alterable values/strings be seperate of each other if the object was duplicated?

[Jaffob]

You could set all the cloned objects to have sequential alterable values from the start, i.e. picture 1 would have index 0, picture 2 would have index 1, etc. Then loop through them all using the qualifier.

[Game_Master]

I tried that to begin with, but sadly, that didn't work

Thanks anyway though, guys

I've just cloned them, and manually given them an ID, which works fine

[Jaffob]

I've just cloned them, and manually given them an ID, which works fine

So it did work then? That's what I was suggesting.

[Game_Master]

It did, but I didn't end up looping them, just copied the behaviours over

[Pixelthief]

different instances of the same active object class have their own alterable values and other variables, in the case of active picture including the picture they will use. If you know any C programming, an active object is effectively like a "Class"- its just a kind of object, and each instance of it is unique and holds its own variables.


it is possible to loop through instances of objects with a qualifier, but you will only be able to execute generic active object events on them (ie anything an active object can do). You will not be able to do any of the Active Picture's special events, because you're referring to a qualifier.