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Garbage when parsing obj-file

fafner (377)
I'm trying to parse an obj-file, which should be simple enough, but have run into some weird issues. My parsing code looks like this:

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while(file) {
	std::string line;
	getline(file, line);
	std::vector<std::string> *tokens = split(line, " ");

	if (tokens->at(0) == "o") {
		name = tokens->at(1);
	}

	if (tokens->at(0) == "v") {
		vecf v;

		v.x = (float)atof(tokens->at(1).c_str());
		v.y = (float)atof(tokens->at(2).c_str());
		v.z = (float)atof(tokens->at(3).c_str());

		vertices.push_back(v);
	}

	if (tokens->at(0) == "f") {
		vec f;

		std::vector<std::string> *xTokens = split(tokens->at(1), "/");
		std::vector<std::string> *yTokens = split(tokens->at(2), "/");
		std::vector<std::string> *zTokens = split(tokens->at(3), "/");

		f.x = (int)atoi(xTokens->at(0).c_str());
		f.y = (int)atoi(yTokens->at(0).c_str());
		f.z = (int)atoi(zTokens->at(0).c_str());

		faces.push_back(f);
		delete xTokens;
		delete yTokens;
		delete zTokens;
	}

	delete tokens;			
}


Probably not the neatest solution, allocating and deleting a lot of vectors, but it should do the job for now. I have run printouts of this ensuring that the values are read correctly from the file. My drawing code looks like this:

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void draw(void) {
	glRotatef(xAngle, 0.0f, 1.0f, 0.0f);
	for(vec face : faces) {
		glBegin(GL_TRIANGLES);
			vecf a = vertices[face.x];
			vecf b = vertices[face.y];
			vecf c = vertices[face.z];
			glVertex3f(a.x, a.y, a.z);
			glVertex3f(b.x, b.y, b.z);
			glVertex3f(c.x, c.y, c.z);

			std::cout << "Drawing vertex - x: " << a.x << "\ty: " << a.y << "\tz: " << a.z << std::endl;
			std::cout << "Drawing vertex - x: " << b.x << "\ty: " << b.y << "\tz: " << b.z << std::endl;
			std::cout << "Drawing vertex - x: " << c.x << "\ty: " << c.y << "\tz: " << c.z << std::endl << std::endl;
		glEnd();
	}
}


I put those last cout-lines in there because the model was being drawn very strangely, and changing every run of the program. When I run it, it prints out, for example


Drawing vertex - x: 4.48416e-44	y: 4.48416e-44	z: 5.60519e-45
Drawing vertex - x: 1	y: 1	z: 1
Drawing vertex - x: 1	y: 1	z: -1

Drawing vertex - x: 4.48416e-44	y: 4.48416e-44	z: 5.60519e-45
Drawing vertex - x: 1	y: 1	z: -1
Drawing vertex - x: -1	y: 1	z: -1


So my question is, does anyone know why these crazy values would be there, when the file is being parsed and read correctly?


Fafner
cire (8284)
It doesn't look like you're handling the face elements in the obj file correctly. The first vertex in the file as it is referred to by a face element will be 1, not 0, so you must adjust your index into vertices.
fafner (377)
Thanks, that was it! Wow, I completely missed the fact that the vertices in a face start from 1, not 0.
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