Processing 1.0 - Processing Discourse - reading numbers from txt file (HAPPY NEW YEAR!)

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reading numbers from txt file (HAPPY NEW YEAR!) (Read 1771 times)

kostino

reading numbers from txt file (HAPPY NEW YEAR!)
Dec 31^st, 2009, 10:48pm

Hi, I 'm making a small game.
At this stage I am trying to draw the level.
So I want to read data from a file and turn them into the level.
the level is a grid, let's say 10 x 10.
So I would like the file to be somewhat like that, so I can easily edit it.

1 1 1 1 1 1 1 1 1 1
1 0 0 0 0 0 0 0 0 1
1 0 1 1 0 0 0 1 0 1
1 0 0 0 0 0 0 0 0 1
1 0 0 0 0 0 1 0 0 1
1 0 0 0 0 0 0 0 0 1
1 0 0 1 0 0 0 0 0 1
1 0 0 0 0 0 1 0 0 1
1 0 0 0 0 0 0 0 0 1
1 1 1 1 1 1 1 1 1 1

1 = wall, 0 = ground.
Catch my drift?

All I need is some direction as to which command to use to read numbers from a .txt file and pass them to a variable. But the separator of numbers should be either " " or ENTER.
Is there any way to do that?
(Perhaps with the LoadBytes() command?)

NoahBuddy

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #1 - Jan 1^st, 2010, 12:04am

If you use loadBytes() You can eliminate spaces. Also, ENTER or just remember to ignore every 10th spot in the array. (and possibly 11th; see control character reference)

Code:

byte[] map = loadBytes("map.txt");
println(map); //Show contents of map

Using this as a map: Quote:

1111111111
1000000001
1011000101
1000000001
1000001001
1000000001
1001000001
1000001001
1000000001
1111111111

On my Windows 2K system, the above code printed:
[0] 49
[1] 49
...
[10] 13
[11] 10
[12] 49
[13] 48
...

Index "[10] 13" and "[11] 10" represent "Line Feed" and "Carriage Return" from ASCII.
Remember that the character '1' is ASCII(numeric value) 49.

References:
http://processing.org/reference/loadBytes_.html
http://processing.org/reference/char_.html

http://en.wikipedia.org/wiki/ASCII
http://en.wikipedia.org/wiki/Control_character

kostino

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #2 - Jan 1^st, 2010, 1:24am

OK, this works good as long as I want to read the contents of a file digit by digit. But what if I wanted to read a file like that:

10 10
1 1 1 1 1 1 1 1 1 1
1 0 0 0 0 0 0 0 0 1
1 0 1 1 0 0 0 1 0 1
1 0 0 0 0 0 0 0 0 1
1 0 0 0 0 0 1 0 0 1
1 0 0 0 0 0 0 0 0 1
1 0 0 1 0 0 0 0 0 1
1 0 0 0 0 0 1 0 0 1
1 0 0 0 0 0 0 0 0 1
1 1 1 1 1 1 1 1 1 1

where the two first numbers are the dimensions of the array following, so as to prepare the program to read it right?
Is there any way to do that? perhaps using Java commands?

NoahBuddy

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #3 - Jan 1^st, 2010, 1:46am

Ah, then I would probably use loadStrings() and split() then convert each string to an int or char, etc.

It may actually be simpler even with the conversion.
Code:

String[] map = loadStrings("map.txt");
String[] dimensions = split(map[0], ' ');
println(dimensions); //shows [0] "10" and [1] "10"
...

http://processing.org/reference/loadStrings_.html
http://processing.org/reference/split_.html
http://processing.org/reference/int_.html

kostino

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #4 - Jan 1^st, 2010, 3:13am

Well, this works fine, but only if the data are in one line...
I also found the splitTokens() command
http://processing.org/reference/splitTokens_.html
which gives the option to include various characters as split points. For example Space and Enter, in my case.
The problem is that it will not recognize (\n) or (^J) (linefeed) as Enter.
Could it have to do with the encoding of my .txt file

NoahBuddy

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #5 - Jan 1^st, 2010, 3:41am

loadStrings() will remove the ENTER from each line so split should work.

If you do want to use splitTokens() with any String:
Are you using " \n" for the delimiter (both a space and new line switch)?
Or simply "\n" alone?

splitTokens() expects a String as a parameter.
Java should match "\n" to the file encoding of your system.

kostino

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #6 - Jan 1^st, 2010, 3:51am

Well, here are the details of what's happening.
The tests have been made with this txt file:
Quote:

1 1 0 0 1 1 0 0
1 1 0 0 1 1 0 0

1.This Code:


String[] map = loadStrings("map.txt");
String[] dimensions = split(map[0], ' ');
println(dimensions);

returns only the first 8 numbers
Quote:

[0] "1"
...
[7] "0"

so I thought I should use
2. This Code:


String[] map = loadStrings("map.txt");
String[] dimensions = splitTokens(map[0], "\n ");
println(dimensions);

but it returns exactly the same...

For you the split() command also works after the first line?

NoahBuddy

Re: reading numbers from txt file (HAPPY NEW YEAR!)
Reply #7 - Jan 1^st, 2010, 4:10am

map[0] is just the first line of the file (created from loadStrings()).

"println(map.length);" will show you how many lines were in the file.

You can use a for loop to cycle through each line.
Code:

String[] dimensions = split(map[0], ' ');

//after map[0], we have what the map looks like
for (int i = 1; i < map.length; i++) {
  String[] rowData = split(map[i], ' ');
  //draw stuff
}

kostino YaBB Newbies Offline Posts: 24	Re: reading numbers from txt file (HAPPY NEW YEAR!) Reply #8 - Jan 1^st, 2010, 4:27am Yep, you are right... stupid me Thanks alot for the help! I think this solves the issue for now...

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