Jaime Oliver wrote:

so each rendering chain starts with a gemhead, each of them have an
argument. the bigger the argument then it is rendered later.

so that:

gemhead 1

is rendered after

gemhead 0

hmm, while your explanation is right, your example is wrong.


[gemhead 2] will be rendered after [gemhead 1].
[gemhead 0] is equivalent to [gemhead] (without args), which actually translates to [gemhead 50].

the reason for this is to be able to easily insert [gemhead]s that are rendered _before_ the "default" gemhead (and _after_ as well).

of course, in theory the [gemhead] could check whether there are no arguments and handle this differently than when an argument "0" is present. but currently it doesn't do so.


everything written here is by heart, so i might be mistaken :-)

nevertheless, i would suggest to never use a rendering order of "0", as it is a borderline case.

I don't know how many levels you can get although i usually see people
write 0-99...

the render-order is represented as floating point.
so 47.7 will be rendered after 47.69; and 2e-9 will be renderend before 1e8
for all practical purposes, this should give you an "infinite" number of levels.


the important thing to notice is that negative render-orders are treated somewhat differently:
- first of all they are always rendered _after_ positive orders. (that is: -1 will be rendered on top of 1000)
- negative render-orders will not be affected by view-point messages
(both of the above are like that to enable simple OSD overlays)

- iirc, negative orders are somehow reversed: that is "-2" is rendered after "-1" (even though -2 is smaller than -1)



mfg.asdr
IOhannes