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Asked By | René Ruppert |
I’m a long term programmer with lots of experience with statically typed languages - maybe that explains why I’m (still) struggling width Godot Script - but I’m getting there 
This said, here’s what I haven’t really understood: when to use .new()?
Why is it
var vec = Vector2(10, 20)
but
var img = Image.new()
?
The answer doesn’t make me fully happy, so I try to make my question clearer. These are the example cases I’m struggling with:
1: var vec = Vector2() - works
2: var img = Image() - does not work - considers “Image()” to be a function
3: var img = Image.new() - works, creates a uninitialised (?) image
4: var img = Image.create(10, 20, false, ...) - works, creates an initialised image
5: var vec = Vector2(1, 2) - works
6: var vec = Vector2.new() - does not work, “new()” not present in built-in type
Why are cases 1 and 2 treated differently? I think this is what it comes down to. Is it correct to say that new()is like a factory method for a reference type where as Vector2 is like an int and thus does not need to be “created”? Or should new() be compared to the new operator of other languages, like C#?
I’m not entirely clear on using new() either. However, i think it’s used in instantiating new classes. When I create my own class, and when I need to use it in a script, I need to use the new() function. Also note that Vector2 is a built-in type, and using new() may be unnecessary for creating a Vector2.
Ertain | 2019-01-01 22:09
Vector2() is a function member of class with the same name, that creates and returns an object of type Vecotr2. That’s why you don’t call new.
p7f | 2019-01-02 11:27
Thank you for the clarification.
Ertain | 2019-01-02 19:11
So why is Vector2() a function member then but Image() is not? And while we’re at it: I do not see Vector2() as a member - just Vector(x, y). This is getting more confusing by the second
René Ruppert | 2019-01-02 19:17
I know the feeling, René. 
Ertain | 2019-01-02 21:36
Why one is member function and anotherone isn’t must be a matter of implementation, and we should ask developers. I guess that Vector2 is used a lot, and making a Vector2 function is a shortcut for programmers. Vector2(x,y) is the member function, but x and y are default 0, so passing Vector2(0,0) is the same as Vector2() just like default arguments in C++, python, and others.
p7f | 2019-01-03 00:37