opengl code to display human body graphics, reading vertices from binary file - c++

Question

I have a binary file which contains the vertices and normals to make a human body graphics in opengl. The graphics are made up of small triangles. The numbers (floating points ) in the binary files are in the order, X, Y, Z of the first vertice of a triangle followed by the normals(x,y,z) to it, Similarly two more of such set completes a triangle.( thus every 18 set of floating numbers in the binary files makes a triangle) and binary files contains several thousands of such triangles.I have written a opengl code in windows form in c++ , to display the graphics, following is the rendering function.I am ignoring the normals and using only vertices
void OpenGL::RenderScene()
{
size_t file_size;
ifstream file;
file.open("male_16_do`enter code here`wn.bin",ios::binary|ios::in);
if(!file){
cout<<"Couldnt find the file"<<endl;
}
file.seekg(0,ios::end);
file_size=file.tellg();
file_size/=(sizeof(float));
file.seekg(0,ios::beg);
std::vector<float> data(file_size);
file.read(reinterpret_cast<char*>(&data[0]),file_size*sizeof(float));
for(size_t i=0;i<file_size;i++){
//cout<<fixed<<setprecision(3)<<data[i]<<endl;
}
vector<float>::iterator iter;
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glTranslatef(1.5f,1.0f,0.0f);
for(iter=data.begin();iter!=data.end();iter++){
glBegin(GL_TRIANGLE_STRIP);
int i=0;
glColor3f(1,0.0f,0.0f);
glVertex3f( data[i], data[i+1], data[i+2]);
glColor3f(1,0.0f,0.0f);
glVertex3f(data[i+6],data[i+7], data[i+8]);
glColor3f(1,0.0f,0.0f);
glVertex3f( data[i+12],data[i+13], data[i+14]);
glEnd();
i=i+18;
}
SwapBuffers(m_hDC);
}
The code appears to be right , but on rendering there is nothing shown in the window, can anyone suggest me what could be possibly wrong here ? Viewport is set to match the width and height of window.

Answer 1

Your for loop with the iterator looks fishy. You're using an iterator over data as well as i:
Make it:
size_t dataLen = data.size();
for(size_t i = 0; i < dataLen; i+= 18) {
glBegin(GL_TRIANGLE_LIST); // your original code mentioned TRI_STRIP.
glColor3f(1,0.0f,0.0f);
glVertex3f( data[i], data[i+1], data[i+2]);
glColor3f(1,0.0f,0.0f);
glVertex3f(data[i+6],data[i+7], data[i+8]);
glColor3f(1,0.0f,0.0f);
glVertex3f( data[i+12],data[i+13], data[i+14]);
glEnd();
}