Hi Michael,

Got an unexpected result when trying to substract the cylindre from this solid.

Hi PaQ, that's a pretty weird one. It seems to refuse to intersect those 2 cylinders.

For the moment to finish your model, if you go to the Front view and stretch out your cutting cylinder to be quite a lot taller in size, like this:



After a certain size it will start to work, so you can do that for the moment to finish this model. I'll dig into it to try and track down the bug.

- Michael

Hey Michael, thanks for the workaround !

How do you come to the conclusion that scaling the cylindre will help to resolve the boolean operation ?

(happy tracking ;))

Hi PaQ,

> How do you come to the conclusion that scaling the cylindre
> will help to resolve the boolean operation ?

Psychic powers. ;)

... Actually kind of a side effect from gathering more information to prepare for debugging. I was just drawing in some new objects to try and repeat the problem to make sure it was not due to something like a messed up trimming boundary. I was also trying some variations to see what happens if I moved stuff around, tried larger or smaller things, etc.. just trying to see if there was some kind pattern that could help me to track down the bug.

If I can find a pattern to the behavior then that can sometimes help me focus on a particular area for the bug.

Then if I find something where the bug is not triggered it can also lead to a workaround.

- Michael

Hi PaQ, it's a bug in the surface/surface intersection calculation.

This particular one does not look like an easy one to tune up myself, but I have bundled it up and sent it to IntegrityWare so that they can take a look at fixing it in the library.

- Michael

How old are these libraries?

Hi Pilou, you mean when did they start developing them?

I think they've been working on different parts of it for the last 10 years or so. So some parts are something like 5 months old and some parts are 10 years old, and various things range in between that.

If you want more information on their library, you could try contacting them, this is their web site: http://integrityware.com/

- Michael

< you mean when did they start developing them?
Yes :) Thx for the infos
it's amazing to see that is always a domain in evolution and that the algos are not definitively resolved!

Hi Pilou - unfortunately processing geometric objects is a difficult area of work, particularly for things that involve an accurate interaction between different shapes.

Shapes come in such an infinite variety that it is not very easy to test every single possible combination.

- Michael

Pilou here is a bit of history http://www.integrityware.com/products/SOLIDS++/history.html

Also read at bottom of this page http://architosh.com/news/1999-11/1104-sr-smlib.phtml (Robert Blomgren, Ph.D....co-developer of AGLib, the first commercially available NURBS library, which was sold to Alias Research in 1994, a subsidiary of Silicon Graphics Inc)

Hi Michael,

Thanks for your investigation ;)

@Yannada: Thx for the info!
I love the "The core of the kernel has been product tested and is essentially complete. " :)

Hi Pilou, well there is a big difference between "feature complete", where major functions have been written, versus "no bugs", which doesn't really ever happen.

- Michael

As us programmers say,
"The last bug is gone when the last user is dead."

Well from my experience there is not such think as bugs free software but one thing is for sure Michael RESPONSIVENESS is all you need.

Also to clarify things the architosh article is from 1999. http://integrityware.com/ Solids++ is NOT used in Vectorworks anymore. VectorWorks 2009 adopted Parasolid Modeling Kernel. More info here why. http://architosh.com/2008/09/architosh-talks-to-dr-biplap-sarkar-about-parasolid/

Anyhow if you look the Tech behind http://integrityware.com/ and http://www.smlib.com/ Michael should have all the Muscle needed to create one of the strongest Modeling apps out there.

Here is one of my favorite parts. http://www.smlib.com/sdlib.html (Michael Lounsbery PhD was a senior researcher and primary developer at Alias of Maya's subdivision surface library and polygon mesh library).



Who Needs TSplines or Imagine and Shape If can get that in MoI? For sure it does not happen from one day to the other. But can you imagine that day...Zaha Hadid and I will be so happy.

I think you have to use the integrityware mesher to use that and Michael has a custom mesher. "The Gibber!" as I like to call it.

Did you Gibb that to render it?

I think a good Gibbing is in order.

Nothing but Gibb! :O

He did overcome that "problem" the first time So I'm sure he can do it again and again...Also note sdlib is not an integrityware product, I think.

I also think the hardest part of Michael job is deciding what not to put into MoI, but to find a way to implement workflows in an intuitive, innovative manner that accelerates the design process. That's the secret to moving forward and Michael seem to be on the ball IMO.

Hi Burr - that one is something different than a mesher - that is an alternate way to define surfaces.

It's more similar to what you see when you select a surface (use Edit/Separate if it is joined) and turn on control points.

@yannada - yeah what I'm doing is not only just wiring tech pieces together (although that certainly can help), but also trying to make a coherent UI that works in a fluid way. Unfortunately that goal is elusive and easily broken. It takes a huge amount of time and care to grow the UI without it becoming difficult to use.

Also yannada, you may need to "not count your chickens before they are hatched". Some libraries that you see may be new and still in their early stages. They are promising but it is not so good to automatically jump to assumptions based on a few images like it sounds like you are doing.

- Michael

He probably thinks thats the "fun part". The hard part is fixing the forum software when it bugs up!

"The milk in this pail will provide me with cream, which I will make into butter, which I will sell in the market, and buy a dozen eggs,..." (that's me The Dreamer)

Anyway Blobism it seems is here to stay and if you can provide the Tools to designer, Architects for sure you are in a win win situation. Now If there is a better way/Code you the only one to Know. I'm just a designer.