ZOrder - Own Engine

[Arie]

Hi, Guys.

Does anyone have a specified way of doing the ZOrder with BitBlt, with several objects?

Thank you,
Arie.

[MoMad]

Put them in an array arranging them by zorder, then blit the array or something

[Arie]

I thought about it but I don't know how to use it.
Does anyone has a ready code for this?
Please help.

Thank you,
Arie.

[Sastraxi]

Just blit them in order from back to front, use an array like that if you want!

[Arie]

My objects are not on an array, not like Object(1 to 10).
I have the objects in different names. How do I get all ordered?

Thank you,
Arie.

[Fox]

You don't. Use an array.

[Arie]

Ok. Got it. My objects are now in an array with no specific bound.
Now how do I arrange the array in the ZOrder?

Thank you so far,
Arie.

[MoMad]

Argggg, just add a zindex to your UDT and use this function

[edit]
function missing
[/edit]

I wrote alot of code and im not sure that it works, ill post again later when i have more time to finish the quicksort function.

Basically what you do is use some kind of a sorting algorythm, search google (vb sort function), and use that to sort your data. The easiest to implement is bubble sort, start from the begining and check every 2 objects and compare, untill entire array is sorted, there is more to this. Search google. I will post a complete function later.

[MoMad]

Alright, im done.

Here is the code, it took me a while to do it but im finally done. Hey Arie, Next time do a search here and if you cant come up with anything, do a search on google, and planet source code. It will give you all the code you want.

' The type UDT needs to have a variable called ZIndex
'  you can call it anything but you have to be sure to do
'  a string replace of TheType to whatever you called yours
' - if you are having ptoblems with it, just reply
Type TheType
    ZIndex As Long
    ' all other stuff goes here
End Type
 
 
' swap objects
Private Sub SwapObj(ByRef i1 As TheType, ByRef i2 As TheType)
    Static i0 As TheType
    i0 = i1
    i1 = i2
    i2 = i0
End Sub
 
' This is the function that you call, it will sort your array as you like
Function ReArrange (ByRef TheArray() As TheType, Optional ByVal Asc As Boolean = True)
    Dim iLBound As Integer
    Dim iUBound As Integer
    
    iLBound = LBound(TheArray)
    iUBound = UBound(TheArray)
    
    ' Quick sort first,
    ' this is a highly rapid and recursive sort algorythm
    ' *note* dont change the 4 here (i dont know why)
    ' here is the original quote:
    ' [quote]
    ' *NOTE*  the value 4 is VERY important here !!!
    ' DO NOT CHANGE 4 FOR A LOWER VALUE !!!
    ' [/quote]
    QuickSort TheArray, 4, iLBound, iUBound
    
    ' Insertion Sort next
    ' This will finish up on the bounds
    Dim iTemp As TheType
    Dim i As Integer
    Dim j As Integer
    
    For i = iLBound + 1 To iUBound
        iTemp = TheArray(i)
        j = i
        
        Do While j > iLBound
            If TheArray(j - 1).ZIndex <= iTemp.ZIndex Then Exit Do
            
            TheArray(j) = TheArray(j - 1)
            j = j - 1
        Loop
        
        TheArray(j) = iTemp
    Next i
    
    ' Now take care of the order
    If Not Asc Then
        ' Reverse the array
        While iLBound < iUBound
            SwapObj TheArray(iLBound), TheArray(iUBound)
            iLBound = iLBound + 1
            iUBound = iUBound - 1
        Wend
    End If
End Function
 
' Function Adapted from a modified version of TriQuickSort,
' by Philippe Lord, posted on PSC on 6/29/2001 2:36:08 AM
' All Props due to their rightful owners, I just put the 
' ideas together :)
Function QuickSort (ByRef iArray() As TheType, ByVal iSplit As Long, _
                    ByVal iMin As Long, ByVal iMax As Long)
   If (iMax - iMin) > iSplit Then
      i = (iMax + iMin) / 2
      
      If iArray(iMin).ZIndex > iArray(i).ZIndex Then SwapObj iArray(iMin), iArray(i)
      If iArray(iMin).ZIndex > iArray(iMax).ZIndex Then SwapObj iArray(iMin), iArray(iMax)
      If iArray(i).ZIndex> iArray(iMax).ZIndex Then SwapObj iArray(i), iArray(iMax)
      
      j = iMax - 1
      SwapObj iArray(i), iArray(j)
      i = iMin
      iTemp = iArray(j).ZIndex
      
      Do
         Do
            i = i + 1
         Loop While iArray(i).ZIndex < iTemp
         
         Do
            j = j - 1
         Loop While iArray(j).ZIndex > iTemp
         
         If j < i Then Exit Do
         SwapObj iArray(i), iArray(j)
      Loop
      
      SwapObj iArray(i), iArray(iMax - 1)
      
      QuickSort iArray, iSplit, iMin, j
      QuickSort iArray, iSplit, i + 1, iMax
   End If
End Function

I havent tested this code but it should work if not, reply and we'll help ya

[Arie]

Oh Man! I will try it out...
I hope it works...

Thank you, MoMad!

I'll reply when done checking.

Thank you all,
Arie.

[Arie]

It works!! Thanks man...
One only thing is wrong here: You create the TheType too much,
to make the array, you should put only the index of every TheType.

Thank you,
Arie.

[MoMad]

No, just do a string replace "TheType" to whatever you call your UDT. It HAS to be a UDT and just switching the zindexes wont work, you have to switch the entire udt.

[Arie]

Ok...
Now, does this code arrange the objects well?

Dim K as Integer, L as Integer, iMax as Integer
 
 For K = 1 To UBound(ObjOrder) - 1
  iMax = K
  For L = (K + 1) To UBound(ObjOrder)
   If Object(L).oPosition.pY < _
      Object(iMax).oPosition.pY Then iMax = L
  Next L
  'Swapping
  Temp = ObjOrder(K)
  ObjOrder(K) = ObjOrder(iMax)
  ObjOrder(iMax) = Temp
 Next K

Thank you,
Arie.

[MoMad]

No and infact i have no idea what the purpose of this is!! Your variables dont match the things they do... you have ObjOrder but then you are using Object instead? You have iMax but then you are assigning it the min value? You are swapping K and iMax but why?

Wait a minute, i remember this algorythm, insertion sort right? Well kindof.. anyways, it kind of makes sense and it kindo doesnt...

...
1 min and copy/paste into vb and testing later....
...

it works!! One problem though?? What is up with Object(k).oPosition?? Isnt it supposed to be ObjOrder(k).oPosition??

[Arie]

You See, iMax is ment to be iMin, and my objects are in the Object array that have all the properties of an object,
and the ObjOrder array is an array of integer, that says the order of the objects by their number.

I hope you understand it a little bit better now, exuse me for not explaining. Can you help me? it does not order my objects correctly...

Please Help!

Thank you,
Arie.

[MoMad]

I see, your problem here is that your array gets ordered correctly but that ordering has no effect whatsoever on your actual object array. Add a field called "ZIndex" to your object array and then order the objects according to the ZIndex...

Actually try this: (you dont need objorder)

Dim K as Integer, L as Integer, iMin as Object
 Dim Temp As Object
 Dim size As Integer
 
 size = UBound(Object)
 For K = LBound(Object) To size - 1
  iMin = Object(K)
  For L = (K + 1) To size
   If Object(L).oPosition.pY < _
      iMin.oPosition.pY Then iMin = Object(L)
  Next L
  'Swapping (the objects)
  Temp = Object(K)
  Object(K) = iMin
  iMin = Temp
 Next K

[Arie]

Thank you very much but I found the solution!
Here's the corrected code:

Dim K As Integer, L As Integer, iMax As Integer, Temp As Integer
 ReDim Preserve ObjOrder(1 To UBound(Object))
 For K = 1 To UBound(ObjOrder)
  ObjOrder(K) = K
 Next K
 
 For K = 1 To UBound(ObjOrder) - 1
  iMax = K
  For L = (K + 1) To UBound(ObjOrder)
   If Object(ObjOrder(L)).oPosition.pY < _
      Object(ObjOrder(iMax)).oPosition.pY Then iMax = L
  Next L
  Temp = ObjOrder(K)
  ObjOrder(K) = ObjOrder(iMax)
  ObjOrder(iMax) = Temp
 Next K

Thank you anyway,
Arie.

[MoMad]

I dont understand, what are you trying to rearrange? The surfaces/objects or the arbitary numbers in objorder array?

[Arie]

My game isn't 2d from up view, it's a 2d game the objects can hide behind the other objects, including players.

Later on, I'll upload my completed game, "Magical Operation".
I hope I won't have any other problems.

Thank you all for helping,
Arie.