Hi, i would like to know if my understanding of z-order and layers is correct (this are probably trivial considerations/questions but i am
a newbie with cocos2d-x
z-order is used by cocos2d to sort sprites to be rendered. So, if i have two sprites A and B, with A having z-order of 0
and B z-order of 1, cocos2d render A first, then B.
If this is correct, i can obtain the same result using two layers, L0 with z-order 0 and L1 with z-order of 1. I could simply
add sprite A to L0, setting the A z-order to 0, and sprite B to L1, setting its z-order to 0. Then, since layer L0 get drawn before L1, A gets drawn before B.
If my understanding is correct, i would like to know what are the best practice. I mean, why i should use more layers if i can use the z-order?
My answers: using two layers i can:
scroll L0 and not L1. this way all childs of L0 are subject to scrolling, while all childs of L1 not. This is easily accomplished managing L0.
Using the z-orders and a single layer, i have to scroll all z=0 childs manually.
using two layers, i can add at runtime elements betwen the two layers easily. For example, let L0 have z=0 and L1 z=1.
If i want to add, at run-time, sprites between L0 and L1, i could easily change z order of L1 to 2 and add another layer at z=1.
using only one layer, i have to change all z-order of nodes with z=1 to z=2…
That is, layers group sprites togheter, and they let create a z-ordering between group of layers.
I would like to hear other reasons to use multiple layers instead of only one. Your experience is welcomed!