Hi people! I've been working on a object generator for my plugin system and I have a doubt in how to store my object data. A simple drawing method is something like this: for(i = 0 ; i < triangles ; i++) { tris = triangles.get(i); v[0] = vertex.get(tris[0]); v[1] = vertex.get(tris[1]); v[2] = vertex.get(tris[2]); glBegin(GL_TRIANGLES); glVertex3f(v[0].x,v[0].y,v[0].z); glVertex3f(v[1].x,v[1].y,v[1].z); glVertex3f(v[2].x,v[2].y,v[2].z); glEnd(); } In a object generator is essential to have index(triangles) and vertex modifiying control, so I need something like a linked list but with the array reading efficiency. I've been testing the STL vector class and i'm not sure if the results are the necessary ones. <vector> testing results: I: inserting R: retrieving D: deleting I: 100: 0 ms R: 100: 0 ms D: 100: 0 ms I: 1000: 0 ms R: 1000: 0 ms D: 1000: 1 ms I: 10000: 5 ms R: 10000: 5 ms D: 10000: 15 ms I: 100000: 52 ms R: 100000: 48 ms D: 100000: 146 ms I: 1000000: 501 ms R: 1000000: 470 ms D: 1000000: 1509 ms I: 10000000: 5148 ms R: 10000000: 4679 ms D: 10000000: 14782 ms My idea is to combine the STL vector and arrays, when I need performance, call some optimize function to convert <vector> data into array and retrieve all information from that array. I'm not sure if I've explained my problem clear... Some suggestion, idea, flame, blabla? Thanks in advance :) PD.: the deleting method if someone is interested: for(k = 0 ; k < init ; k++) { std::swap(v[init-k-1], v.back()); v.pop_back(); }

Hi bud,

Altering an STL vectors contents via its interface is going to be no slower that altering a typical array.

I think the question you should be asking yourself here is whether you really need to be doing this or not.

For what reason do you want to do this?

Dave

Quote:Original post by pfc6
so I need something like a linked list but with the array reading efficiency.

That would (roughly) be std::deque but there are other alternatives too.

Quote:Original post by pfc6
My idea is to combine the STL vector and arrays, when I need performance, call some optimize function to convert <vector> data into array and retrieve all information from that array.

Pointless, std::vector is a dynamic array, std::vector is not implementated with a linked list.

You could do much better with your drawing code and you're probably using std::vector ineffectively or using the wrong data structure for the job, but it's hard to say without seeing what you're actually doing.

[Edited by - snk_kid on June 1, 2006 5:02:59 AM]

When I need to modify for example an object face doing an extrude, I need to add more faces and modify my indexes 'vector'. Accesing to the STL vector element is exactly the same as accessing to an array element?. I have a trouble with this... accessing to an 'real' array is faster I think...

I am mistaken?

Thanks again.

Thanks for all the replys.