read an input file

hello everybody,

I need ur help, about how i can read from an input file for opengl, I wrote the code c++ but i cannot run it when i want to use it in opengl. please let me know(urgently).

thanks,
zeytin

Can you be a little more specific? openGl have nothing to do with file system. :-S
If you want to load a 3d model from a file you should use a library (google can help you here) or study the file format and read it by yourself (obj and 3ds file are easy to parse).

hello again,

this can be an example of input file;
vertex 32 320
vertex 12 120
polyline 2 2
vertex 4 110
vertex 3 150

i wrote the code in c++, it reads all information, but i do not know how i can use the code in opengl(or whether i can use it). (i am really new, so i will appreciate for all helps).

thanks again

Hi,

Please see the below flat file, that i use to store the latitude and longitude information for a perticulat place in the map.

Here i tried to display the lat/long information, based on the mouse movement.

In the below file, # represents comment, otherwise data to be read.

---------------------------------------------------

X Y D Dg Mn Se D Dg Mn Se Place Name

---------------------------------------------------

1503 547 N 13 04 07.5 E 77 31 10.31 Bangalore
1428 425 N 19 03 43.0 E 72 51 40.78 Mumbai
1496 223 N 28 41 26.1 E 77 15 21.09 Delhi
1677 353 N 22 40 29.4 E 88 25 04.68 Kolkata
1520 458 N 17 28 35.3 E 78 23 54.37 Hyderabad
1551 549 N 13 04 07.5 E 80 14 38.90 Chennai
#----------------------------------------------------

below is mu code to read the above file.

void readFromFile (int x, int y) {
int wxCord, wyCord,directLat,directLong;
char c;
char str[100],placeName[12];

    inStream.open(latlongfile,ios::in);
    if (!inStream) {
            cout<<"File 'latlongfile' not found: "<<endl;
            exit(0);
    }
    while(!inStream.eof()) {
            inStream>>c;
            if (c == '#') {
                    inStream.getline(str,100);
            }
            else {
            inStream>>wxCord>>wyCord>>latDirection>>latDeg>>latMin>>latSec>>longDirection>>longDeg>>longMin>>longSec>>placeName;

}
if ( (x >= (wxCord-10) && x <= (wxCord+10)) && ( y >= (wyCord-10) && y <= (wyCord+10))) {
if(latDirection == ‘S’ || latDirection == ‘W’)
directLat *=-1;
if(longDirection == ‘S’ || longDirection == ‘W’)
directLong *=-1;

                    latitude  = directLat * (latDeg  + (latMin/60) +  (latSec/3600));
                    longitude = directLong * (longDeg + (longMin/60) + (longSec/3600));
                    strcpy(::placeName,placeName);
                    if (hits == 1) {
                    xx = hits;
                    lat1 = latitude;
                    long1 = longitude;
                    strcpy(srcPlaceName1,placeName);
                    }
                    else {
                    lat2 = latitude;
                    long2 = longitude;
                    strcpy(dstPlaceName2,placeName);
                    dist = distanceBetweenPoints(lat1, long1, lat2, long2);
                    }

                    inStream.close();
                    break;
                    }

}

so once the values from the mouse movement is read, it is compared with the flat file X and Y, and particular place lat/long is calculated and displayed on the screen.

if any doubts let me know.

thanks,
SantoS