How to clear all values in a NewType array very quickly?

[TheoTheoderich]

Hello,

I have a question regarding NewType Arrays.
It is possible to clear such array with just one command without the need to loop through the whole array to set every field to zero?


I am using this newtype array for the pathfinding in my game Settle the World.
But i have to clear the whole array for every unit which uses the pathfinding.
(to clear means pathmap(x,y)\tile = 0, pathmap(x,y)\g = 0, etc.)



Especially on a 68000 CPU it took a lot of time to loop through the whole array to set the newtype fields to 0.

NEWTYPE .tpathmap
  tile.b                ; Obstacle or not
  g.w                   ; G cost / see A*-Algorithm
  h.w                   ; H cost / see A*-Algorithm
  f.w                   ; F cost / see A*-Algorithm
  dir.b                 ; Direction
End NEWTYPE
Dim pathmap.tpathmap(#mapWidth, #mapHeight)

I already tried to DIM the pathmap again, hoping it would be cleared then...but unfortunately that did not work.

Do you have any ideas how I can otherwise set all the fields in a NewType array to the value = 0 very quickly?

Thank you very much

[Honitos]

The command ClearType is not a solution?

[TheoTheoderich]

Maybe...but how to use it?

ClearType pathmap()

does not work.
Error message is saying:
"Array is not a list!"

[Honitos]

Instead of using an array, I'd suggest to use a dynamic list in combination with a newtype.

So you can use ClearType and ClearList to clear a single entry or the complete list.

[Honitos]

You *could* clear the complete array by clearing the corresponding memory area this way:

memaddress.l = &myArray()
memlength.l = <array size> * SizeOf.<newtypename>

FillMem memaddress,memlength ; command from RiAmosFuncLib

That should work too, but is a kind of hack in my eyes...

[TheoTheoderich]

Thank you for your answer.

As far as i know lists are limited to one dimension.
And my map is stored in an 2d array.

So i think lists are more complicated to handle :-(
Because the pathfinding is using X and Y coordinates for the units.

Unfortunately, I can only program very simply...so i have no clue how to use an 1d list array with data from a 2d map array.

EDIT:
Thanx, i will try your idea with clearing the memory area.
But i agree...sounds like a hack...

[TheoTheoderich]

Clearing the array mem was not working for me.

I figured out another solution, but I have to run a lot of tests, if this is working correct.

I made a copy ("pathmapcopy") of the the "pathmap" array which is always empty.

Instead of looping through all 160 x 128 tiles to clear the "pathmap" array, I make a copy of the empty "pathmapcopy" array to the "pathmap" array.

CopyMem_ &pathmapcopy(0,0), &pathmap(0,0), (#mapWidth * #mapHeight) * SizeOf.tpathmap

On a plain 68000 CPU this is slightly faster than looping through the pathmap array....but it takes much more memory because of the second array.
So it feels like wasting memory ....but it seems to work.


I need to have fast pathfinding in my game, because at the end of a turn the native units are moved.
There are (at the moment for testing) round about 220 native units in the game. But only some of them will need to calculate a path on turn end.
Most of the time they are moving only from tile to tile, so no pathfinding is needed.
But sometimes, for example if they move too far away from their home village or want to attack a city of a player, the pathfinding is needed.

[E-Penguin]

If your array can live in chipmem then you can use the blitter to clear it very quickly. Asm code here but you can call it from blitz
http://amigadev.elowar.com/read/ADCD.../node02DE.html

If you want to put it in FastMem then maybe use AllocMem/FreeMem. There's a flag to get the memory cleared on initialisation
http://amigadev.elowar.com/read/ADCD.../node0332.html

The InitBank blitz command should do the same. You'll need to then create a pointer of your desired type to point to the memory address returned.

In all the cases I suspect there's a way to just avoid setting everything to zero first. I don't know the A* algorithm but I guess you're iterating through your array to generate the path and the G, H and F costs need to be cleared before doing the calculations? Why not just clear them at the start of the calculation loop for that cell?