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# Miserable file loader

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ifstream file;
file.open(FILE1);
/*
File format should be as follows:
1. file should have no carriage returns on a blank line (no blank lines)
2. break files into sections of 3 lines
a) first line is x coordinate
b) second line is y coordinate
c) third line is z coordinate
NOTE: There is no error checking for the file, so hope to god it works...
*/
for (long int a=1; !file.eof(); a++)
{
vertex.resize(a+1);
getline(file,vertex[a].xx);	// grab first line

getline(file,vertex[a].yy);	// grab second line

getline(file,vertex[a].zz);	// grab third line

vertex[a].x = atof(vertex[a].xx.c_str());	// convert x to a double

vertex[a].y = atof(vertex[a].yy.c_str());	// convert y to a double

vertex[a].z = atof(vertex[a].zz.c_str());	// convert z to a double

}
file.close();	// be cleanly...


Thanks!

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1) store number of vertices up front and only resize() once.

2) use >> into floats instead of getline().

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I don''t really know the answer to your problem, but i''ve got a few suggestions for your code.

First of all if you didn''t already at the begining of your progmram include this:
#include <iostream>

The when you open your file, this is how the line should look:
file.open(FILE1,ios:in);

just something i learned in my AP Comp Sci class.

and like niyaw said use ">>" operator

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I can''t get it... I now have this

  	ifstream file;	file.open(FILE1);/*File format should be as follows:	1. file should have no carriage returns on a blank line (no blank lines)	2. break files into sections of 3 lines		a) first line is x coordinate		b) second line is y coordinate		c) third line is z coordinateNOTE: There is no error checking for the file, so hope to god it works...*/	for (long int a=1; !file.eof(); a++)	{		//getline(file,vertex[a].xx);	// grab first line		//getline(file,vertex[a].yy);	// grab second line		//getline(file,vertex[a].zz);	// grab third line		file >> (float)vertex[a].x;	// convert x to a double		file >> (float)vertex[a].y; // convert y to a double		file >> (float)vertex[a].z;	// convert z to a double	}	vertex.resize(a+1);	file.close();	// be cleanly...

Needless to say it does not work!
Thanks again!

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try running a for loop before the loading process to check how many lines the file is:

int i=0;
while (!file.eof())
{
i++;
}
i = (i/3)+1; // since you load in 3 things, and you want to make sure there is enough space for the vector

Then resize it:

vertex.resize(i);

Then run your original for loop. That should eliminate your problem, but the question remains as to how long it takes to find the eof mark. It should run quickly I think, but could someone back me up on that or disprove my theory?

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!file.eof();

Think this is the problem!!! I think that testing the end of file every time you loop, ins''t a good idea!!! Some how, you must to know about the file size to check the end of file. Files like 3ds, organize the data in chunks with the segmentes of the data in the file. Those files says the dize of thme selves, I think, sou you must doo the same to avoid those trobles....

Filami

Techno Grooves

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You should use a standard file format (i suggust ms3d or md2), because loaders are already written for them (and if you want to write one, the documentation is avaliable), and they are tried and tested. You also wont find yourself writing an editor for your format. If you are using your format for something other than rendering a model, look at the other formats anyway. They should give you a few ideas.

btw i think its atof() that is slowing you down. There are ways to read the value directly. One more thing, you really shouldn''t store the vertex data as a string if you arn''t going to use it again, but that shouldnt matter if you are going to skip the conversion.

"Free advice is seldom cheap."
-- Rule of Acquisition #59

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something like

    	ifstream file;	file.open(FILE1);/*File format should be as follows:	1. file should have no carriage returns on a blank line (no blank lines)	2. first number in the file is total number of vertices	3. break files into sections of 3 lines		a) first line is x coordinate		b) second line is y coordinate		c) third line is z coordinateNOTE: There is no error checking for the file, so hope to god it works...*/	int num_vertices;	file >> num_vertices;	vertex.clear();	vertex.reserve(num_vertices);	for (;;)	{		// get three numbers, Vertex is your vertex type		Vertex v;		file >> v.x >> v.y >> v.z;		// check for end of file		if (file.eof()) break;		// add vertex to your vector		vertex.push_back(v);	}	file.close();	// be cleanly...

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I got it!

  	        apvector<VERTEX> vertex(50000);                ...        fstream file;	file.open(FILE1, ios::binary | ios::in);/*File format should be as follows:	1. file should have no carriage returns on a blank line (no blank lines)	2. break files into sections of 3 lines		a) first line is x coordinate		b) second line is y coordinate		c) third line is z coordinateNOTE: There is no error checking for the file, so hope to god it works...*/	for (long int a=1; !file.eof(); a++)	{		file >> vertex[a].x;	// convert x to a double		file >> vertex[a].y; // convert y to a double		file >> vertex[a].z;	// convert z to a double	}	vertex.resize(a+1);	file.close();	// be cleanly...

Thanks Everyone!!

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I got it!

  	        apvector<VERTEX> vertex(50000);                ...        fstream file;	file.open(FILE1, ios::binary | ios::in);/*File format should be as follows:	1. file should have no carriage returns on a blank line (no blank lines)	2. break files into sections of 3 lines		a) first line is x coordinate		b) second line is y coordinate		c) third line is z coordinateNOTE: There is no error checking for the file, so hope to god it works...*/	for (long int a=1; !file.eof(); a++)	{		file >> vertex[a].x;	// convert x to a double		file >> vertex[a].y; // convert y to a double		file >> vertex[a].z;	// convert z to a double	}	vertex.resize(a+1);	file.close();	// be cleanly...

Thanks Everyone!!

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