How to make a map data array.

Hello this is my first post in this community, its nice to meet you all :) on petit computer I learned, with the help of a tutorial on the petit computer wiki, how to use an array and BGPUT to make a simple map w/ collision detection. Something like this

DIM MAP [32,24] 
RESTORE @MAP
FOR I=0 TO 23
READ MAPLINE$
NEXT
FOR J=0 TO 31
MAP [J,I]
IF MID$[MAPLINE $,J,I]=="1"
IF MAP [J,I] THEN BGPUT 0,J,I,45,0,0,0

'Now a loop divide py px/8 to get collision data with 1's to represent ground and what not 

however it doesn't seem to be working in smilebasic. I was wondering what changes I should make to the code to get it to work? Or if I have to find another way to pull map data from the array. Any help is appreciated. Thanks for reading :)

Also I forgot to add a couple more next statement's in this code. I have them in my smile basic code on my 3ds though so just put them where they should be lol

I suggest taking a gander at http://smilebasic.com/en/reference/ if you have not already, it may give you an idea as to what's going on. Also, mind telling what the error/line given is? It may help us to help you.

Ok the error I'm given is "out of data in 0:5" line 0:5 is the code

READ MAPLINE $

which I know calls back to the previous code "RETURN @MAP" which in turn points to the actual map data. I can assume this means I'm not using the DATA commands properly? Or maybe it can't find the @map tag. Thanks for the help :) I'll try reading through the smile basic reference website again as well, maybe there is something I missed.

My best guess it that you have malformed DATA. Other problems I think I'm seeing: The READ MAPLINE$ loop eats and discards all the data. You want it to encompass the lower part where you actually use MAPLINE$. I'm not sure what's going on with that MAP[J,I] either. The line is an empty statement, or worse, will break thinking MAP is a command.

IF MID$[MAPLINE $,J,I]=="1"
IF MAP [J,I] THEN BGPUT 0,J,I,45,0,0,0

These lines look like they should be combined, or maybe just IF MID$(MAPLINE$,J,I)=="1" THEN BGPUT 0,J,I,45,0,0,0

Thank you that fixed my data problem. I apparently made it one line too long, and thats what caused the error. Ive updated my code to

ACLS:CLEAR
DIM MAP [32,24]
RESTORE @MAP
FOR I=0 TO 23
READ MAPLINE$
FOR J=0 TO 31
  MAP [J,I]=0
   IF MID$(MAPLINE$,J,I)=="1" then MAP [J,I]=1
  Next
Next
FOR I=0 TO 23
 FOR J=0 TO 31
  IF MAP[J,I] THEN BGPUT 1,J,I,45,0,0,0
 NEXT
NEXT

@ loop
'player movement and col detection

@MAP
'mapdata

the code seems to be working the only problem is that it gives me the error "Illegal function call in 0:13(BGPUT) I'm not sure what I'm doing wrong, the code should know that if MAP [J,I] =1 then BGPUT a tile on the coordinates with a "1" in the DATA. That's my theory anyway.

If you look at the reference page that Lumage linked earlier, the definition of BGPUT takes only 4 parameters,and yours has a couple extra. It should look like this:

BGPUT <layer>, <x coord>, <y coord>, <value>

I think if you fix that it should work.

Maybe the BG layer isn't defined or visible. But it looks like you are doing an ACLS, which should set layer visibility, but you still have to define the layer size and setup the screen. You might try setting the following after ACLS:

XSCREEN 0, 128, 4
BGSCREEN 0,64,64
BGSHOW 0
.....
' Then when you do your bgput make sure you define it like this:
BGPUT 0, J, I, 1

To recap what those commands do: XSCREEN sets the screen mode (0 is just the top screen), and allocates space for sprites (128 of them), and bg layers (4 of them). BGSCREEN sets up the size of your BG layers. In your case, layer 0 will contain 64x64 grid of tiles BGSHOW just ensures that the layer given as a parameter is visible (drawn). If it still doesn't work after making those adjustments, just let me know, and I'll set up an example and send you a key.

You're not trying to use tile 0 are you? SB always uses 0 as the default "invisible" tile data, even if it has a graphic in the tile sheet. It's not going to show up unless you use some tricks, but I recommend you just move the tile somewhere else in the sheet if that's the case.

It kind of works. It's now showing only the second line in the map DATA. I tried experimenting with the variables of bgscreen and xscreen, but that didn't seem to help. If its not too much trouble, a program key will definitely help.

It's hard to tell from the example code, since I can't see how your map data is formatted, but if I had to guess, it looks like the string you are storing your map data in is fed a line at a time from your READ loop, and each succession in the loop just overwrites what the last iteration read. Meaning, your MAPLINE$ only contains one row of data. Anyway, I'll add an example real quick and link it in this post. EDIT: Here's an example key, I just tweaked your example code a little bit -> [ 7KS3EPJX ]

Awesome thanks for all the help, I got it running now :). You were probably right about the loop overwriting map data. i think petit computer handled loops differently, so that's probably why it didn't transfer over too well.

You're welcome; happy to help :)