Add the ability for a display group to sort itself

[marksolar2d]

Hey would it be possible to add a sort() function to display groups?

Currently I give each display object a calculated z value and do a table.sort to depth sort the display objects. This requires creating a tmp table for the display objects to be inserted to, sorted and then reinserted into the display group. I imagine doing this in the engine would be much faster than lua. Currently groups with 1k+ objects can take a frame or two to sort.

    local function depthSort(group)
      --depth sort this
      local objects = {}
      for i = 1, group.numChildren do 
        objects[#objects+1] = group[i]
      end
      table.sort( objects, function(a,b) return a.z < b.z end )
      for i = 1, #objects do 
        group:insert( objects[i] ) 
      end
    end

    depthSort(group)

It would be great for devs to be able to simply call group:sort() to perform a low-level depth sort. If no z value is given the object is simply ignored so this would not affect any current code.

[depilz]

Is there any chance to keep them sorted on every new insert?

If this is your only option I can try to implement it next week, it shouldn't take more than a couple of hours .

[marksolar2d]

In the end I went to a sorted insert system. I now binary search the display group to decide where to insert new objects. It was a pain but in the end much faster than resorting the entire group in lua.