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KurtCob
01-09-2002, 11:57 PM
Hello guys,

I'm with a big problem, and I'm trying to find the best solution for this problem, I will try to explain :

I have a model (that is digitized in slices / sections), now I would like to render it, it means that I have to make the faces and I also want to export it in some formats, but not in slices, in faces, the question is : How to create the faces (QUADS or triangles) based in my slices model ?

Any help will be apreciated

Thank you for the moment.

Happy 2002 for everybody.

Kurt

BTW : is there any brazilian guy here ?

DFrey
01-10-2002, 06:55 AM
Could you give a better description of what a slice is?

KurtCob
01-10-2002, 11:25 PM
Lets imagine that you have a bread, and when you want to cut a peace for you, you will have a slice of the bread.

Lets imagine a rectangle :

---------------
| |
| |
| |
| |
---------------

I have to scan this rectangle, the device to digitize that I'm using will make sections (slices) of this rectangle, like this :

---------------
|---------------|
|---------------|
|---------------|
|---------------|
---------------

Then I will have a file with the coordinates X Y Z for all the sections that my digitizer generated. Slices are parallel cuts of the object.

Hope that I was clear enough.
Tnks
Kurt

KurtCob
01-10-2002, 11:29 PM
The fisrt rectangle was not good

----------------
| |
| |
| |
| |
----------------

----------------
|----------------|
|----------------|
|----------------|
|----------------|
----------------

Tnks
Kurt

KurtCob
01-10-2002, 11:30 PM
Not yet, I think you can understand what I mean.

Thank you
Best regards
Kurt

DFrey
01-11-2002, 05:59 AM
What I was really looking for is more information on what data makes up a slice, that is, is it a scalar field? Or is it just a series of points? How are the points distributed, throughout or only on the surface?

KurtCob
01-11-2002, 06:38 AM
Is just a serie of points that describe the surface of my object.

Hope I was clear.

Thank you
Best regards

DFrey
01-11-2002, 06:52 AM
Ok, good. Is the outline of each slice always simple? Or can it be complex, i.e. made up of multiple disconnected contours? If it is multiple contours I would suggest something along the lines of the marching cubes algorithm. If the contour of the slice is always simple, then finding the hull should be quite trivial.

[This message has been edited by DFrey (edited 01-11-2002).]

KurtCob
01-11-2002, 07:32 AM
Can you be more clear , sorry, i'm only 16 years old.

And I really will apreciate your help.

Tnks
Kurt

Zw
01-12-2002, 06:46 PM
Hi, DFrey

It seems that you are trying to find a all-purpose save-strategy to save your slices data.

Do you know about VTK? I suggest visit http://www.kitware.com/ to download one, and see how they organize the data.

In the simplest, just like KurtCob'idea,to save data to two-dimension array, but at least you can decide how to use your array.

Is it right? I also don't know much, and I save and draw my slice-sphere follow what the MATLAB's function sphere() does.