Read large amount of numbers from file
Hallo,
I am working on a function for reading large amount of data from a file. Each line contains the information needed to build a triangle. What is the best way to do this?
Right now Im tying to read each line, convert it into a float and than create a triangle before I read the next line. Is there a smarter way? Would be great to get some input on this.
Code:
std::string currentLine; // Variable that holds the current line
// we are using.
int nrLines = 0; // Variable for checking how many lines
// there are in the file
// Open file
std::ifstream myFile (FileName);
/*
// The content of the file
random line 11 ra
V: 2.020,0.121,12.1212 4.657,11.31,9.11 4.7,11.00,5.411
V: 2.020,0.121,12.1212 4.657,11.31,9.11 4.7,11.00,5.411
V: 2.020,0.121,12.1212 4.657,11.31,9.11 4.7,11.00,5.411
V: 2.020,0.121,12.1212 4.657,11.31,9.11 4.7,11.00,5.411
*/
// An array of strings, for reading the 3 vertexes we will later
// use. Note that there is 3 vertexes, each made up of 3
// cordinates
std::string vertex[3][3];
if (myFile.is_open())
{
// While the file is open, we read the info and construct triangles
while (! myFile.eof())
{
// Read line
getline(myFile, currentLine);
// Check if this line holds vertex information. If the line starts
// with V, we will use it.
if (currentLine[0] == 'V')
{
// Break the line into different components, so that we can
// create 3 different vertexes for each cordinate in the file
// V: 0.0,0.0,0.0 1.0,1.0,1.0 2.0,2.0,2.0
// Variable for keeping track of which character in currentLine
// we are reading, it starts at 2, as the 3 first characters
// are not part of the number we are tring to read
int x = 3;
// Make a loop for creating 3 vertexes
for (int i = 0; i < 3; i++)
{
// Loop for looping throught the three cordinates of each
// vertex
for (int j = 0; j < 3; j++)
{
// Make sure the vertex string we are writing to now is
// empty
vertex[i][j].clear();
// Make sure the current character is part of the number
while (currentLine[x] != ',' && currentLine[x] != ' ')
{
// If the current character is part of a number,
// append it to the vertex string
vertex[i][j].push_back(currentLine[x]);
x++;
}
x++;
}
}
// Convert the string into floats
}
// Increment the line counter
nrLines++;
}
// Finished with reading the file, close it
myFile.close();
}
I also have a problem with the printing. I get a lot of random characters after i have printed the numbers.
Code:
// Print the thing
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
std::cout << vertex[i][j] << " ";
}
std::cout << " - ";
}
std::cout << std::endl;
Thanks for your time:)
EDIT:
Right now Im trying to load my own file format, which kind of suck. Does anyone know where to find good information on how to load .obj files? I have looked, but could not find anything good (simple)
Thanks again
