2d image app

alexenduro · October 12th, 2011, 09:01 AM

Hi everibody! I have to create an app that draws a map reading data from a text file : for example the text file can be like

. index x y orientation
vertex 1 0 0 0
vertex 2 5 0 0.5
vertex 3 10 2 0.3

so i need to do in java something like fscanf does in c (fscanf scans the text file for known formatted data... example, in the file i written i know each line has a string float float float and i need to put them into a specific data structure that can be a list of elements "vertex"

next, when i have all the data, draw a simple image rappresenting the data..

my questions are...
there is a function like fscanf?

and then.. what's better for drawing the 2d map? i have tu use Opengl? At the end i have to draw the image pixel by pixel.. i hope there is something easier then openGL

jonbonazza · October 12th, 2011, 10:31 AM

You need to use an input stream. There are various options here, but the one I would use is a DataInputStream.

alexenduro · October 12th, 2011, 10:49 AM

Thanks a lot Jonbonazza! It seems perfect ! And about the drawing, ideas?

alexenduro · October 13th, 2011, 05:32 AM

Quote:

Originally Posted by jonbonazza

You need to use an input stream. There are various options here, but the one I would use is a DataInputStream.

today i was trying to use that but i have got some problems to read string with datainputsream.. how can i do if the file its like

newyork 1 2
rome 5 7

so I know each line begins with a string but i dont know how long it is and i need to put the names in a String value?In c its easy, i simply put something like fscanf(file,"%s %d %d\n",name,x,y); and %s gets the string, no matter how long it is..

Thanks for help!

jonbonazza · October 13th, 2011, 10:46 AM

It doesn't matter how long it is. to read the first line of the above text, you would do this:

Code:

DataInputStream dis = new DataInputStream(new FileInputStream(new File(filename)));
String city = dis.readUTF();
int param1 = dis.readInt();
int param2 = dis.readInt();

It will automatically read in the proper number of bytes and convert it to the proper datatype.

EDIT: Actually, I made a mistake. DataInputStream reads and writes binary files. If you want to read a text file, you will want to just use a FileInputStream.

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