WARNING: Flurry of questions about to ensue...

Post here for help on using FreeCAD's graphical user interface (GUI).
GrantRobertson
Posts: 31
Joined: Sat May 19, 2018 11:41 pm
Contact:

Re: WARNING: Flurry of questions about to ensue...

Postby GrantRobertson » Thu Aug 16, 2018 7:52 pm

GeneFC wrote:
Thu Aug 16, 2018 5:52 pm
Second, it is quite clear that you do not really understand the scope of the task to professionally document FreeCAD. I took a look at your work references that were linked. Nice job, but none of those items would appear to be even 10% as complex as FreeCAD. In addition, FreeCAD is evolving daily, including areas that are important to beginners. An example is the Sketcher WB, which is a core functionality for much of FreeCAD. Many important changes have been made in the past few months.
Oh, I am well aware of the scope and magnitude of the project. That is why I chose it. Please don't think that what I have posted on my personal blog is the be all end all of my work. There is a lot more stuff that I have done professionally, that is not on my blog.
GrantRobertson
Posts: 31
Joined: Sat May 19, 2018 11:41 pm
Contact:

Re: WARNING: Flurry of questions about to ensue...

Postby GrantRobertson » Thu Aug 16, 2018 7:57 pm

Everyone,

Please don't think my intention is to write a single, huge tome and only release the whole thing once it is completely finished. As I write various chapters and tutorials, I will post them for review and release them independently. However, they will all be designed to be part of a cohesive whole, rather than individual dribs and drabs of disconnected information. I will try to plan around upcoming changes (if I can get any information about said changes) and start by writing about things that either won't be changing soon, or are important for beginners now.
TheMarkster
Posts: 411
Joined: Thu Apr 05, 2018 1:53 am

Re: WARNING: Flurry of questions about to ensue...

Postby TheMarkster » Thu Aug 16, 2018 8:09 pm

GrantRobertson wrote:
Thu Aug 16, 2018 7:48 pm

How about this?:

A) I will create one thread in the "Tutorials and videos" forum to discuss the book itself.

B) However, it is commonly accepted internet forum practice to keep each topic in a separate thread. That way it is easy for people to find them later. Even if I never finish the book, the questions and answers will prove beneficial in and of themselves. If they are all bundled up into a single thread, with a subject line that keeps changing, that will make it harder for people to find information in the forums.
Looks good to me. Organize it how you think best.
User avatar
sgrogan
Posts: 4435
Joined: Wed Oct 22, 2014 5:02 pm

Re: WARNING: Flurry of questions about to ensue...

Postby sgrogan » Thu Aug 16, 2018 8:41 pm

GrantRobertson wrote:
Thu Aug 16, 2018 5:20 pm
A) What do you mean by "proper toponaming"?
Toponaming or Topilogical Naming refer's to how the model topology is stored internally. Note: Topology and Geometry are not the same.https://en.wikipedia.org/wiki/Geometry_and_topology
I'll use your map sketch to face as an example.
Imagine, you create a rectangular sketch, pad it, then map a sketch to a face. Internally there is a link, so Sketch is mapped to Face6(say). Now go back and edit the base sketch to be a triangle. Internally FreeCAD's CAD kernal (OCCT) will renumber the faces. Face6 no longer exists so the sketch reference and your model is broken. Same is true when using links to external geometry and adding fillets.

Even the commercial packages suffer from this, but to a much lesser degree. I personally still map sketches to faces all the time. It's faster and easier, although it leads to a less robust model. I usually have a good idea about the topology and my models are typically simple enough that if I do break it it's easily fixed. Of course the more complicated the model is the more important robustness is.
GrantRobertson wrote:
Thu Aug 16, 2018 5:20 pm
B) Do you really expect so much of the program to completely change? So much so that any new documentation would become irrelevant? It doesn't seem likely that a group of developers would work so hard making changes such as those introduced in 0.17, only to make them irrelevant in the very next release.
The change would be in 0.19.
Historically FreeCAD daily builds could almost be considered a "rolling release" It was necessary to break from this tradition between 0.16 and 0.17 to get all the Part Design improvements. There was so much inter-related stuff that it was necessary to put it in master and figure it out. It took us 2 years to get to the 0.17 release and the Part Design stuff came in almost immediately after 0.16 release.
There is a development branch in testing now that will bring a similar level of improvement with the potential to have the same level of disruption.
I think as a community we are coming to a consensus that we should do an 0.18 release ASAP (ie by the end of the year)
Then add the big changes at the beginning of the 0.19 dev cycle. Toponaming improvements are potentially included in these big changes. With luck mapping sketches to faces will again be the prefered method.
GrantRobertson wrote:
Thu Aug 16, 2018 5:20 pm
C) If large parts of a book would become irrelevant, then what is to say that a large number of short tutorials or Wiki pages would not go irrelevant also?

They probably will be, hence the challenge of documentation.
GrantRobertson
Posts: 31
Joined: Sat May 19, 2018 11:41 pm
Contact:

Re: WARNING: Flurry of questions about to ensue...

Postby GrantRobertson » Fri Aug 17, 2018 2:57 am

sgrogan wrote:
Thu Aug 16, 2018 8:41 pm
Note: Topology and Geometry are not the same.https://en.wikipedia.org/wiki/Geometry_and_topology

OK, that Wikipedia article was way over my head. Or at least it used lots of terminology with which I am not familiar.

I have always been told that the difference between topology and geometry is that topology is concerned with continuous surfaces and geometry is concerned with the actual shape and position of those surfaces. In other words, topology says a cube and a sphere are the same, whereas geometry says they are different. In topology, you don't get a different "thing" until you put a hole in it. So a torus is different from a sphere but the same as a coffee cup. A mobius strip is topologically a continuous single surface, whereas geometrically, it is a weird loop thing in 3-D space.

But that is a discussion for another day.... or lifetime.

sgrogan wrote:
Thu Aug 16, 2018 8:41 pm
Toponaming or Topilogical Naming refer's to how the model topology is stored internally. ...
I'll use your map sketch to face as an example.
....

The change would be in 0.19.
...
There is a development branch in testing now that will bring a similar level of improvement with the potential to have the same level of disruption.
... we should do an 0.18 release ASAP (ie by the end of the year)
Then add the big changes at the beginning of the 0.19 dev cycle. Toponaming improvements are potentially included in these big changes. With luck mapping sketches to faces will again be the prefered method.
So "Toponaming" is your new method for naming faces such that existing face names will not change when sketches are radically modified?

Did you go with something like UUIDs for the faces as opposed to a simple sequential numbering? Personally, I would have gone with a system where the "names" of the faces were merely another attribute in a graph node. If a face node held any references to any sketch nodes, then I would ask the user before removing that face node. But then, I am not a developer for this project and I don't know the rest of the intricacies of the data structures.

Anyway, what will be important for my writing is what things will or won't change in the actual user interface over time. If I write about using Datum Planes to put sketches on and mention that that is the preferred method for now... Later, when it is safe to put sketches onto faces again, all I will likely have to change is which method I say is the preferred one. I'm guessing that the actual steps to create a Datum Plane and put a sketch on it will not change that much.

Well, we can discuss these issues in my other tread (which I have yet to start) about the actual book. That thread will be for discussions of which aspects of FreeCAD I should write about first and which are likely to change sooner rather than later.
TheMarkster
Posts: 411
Joined: Thu Apr 05, 2018 1:53 am

Re: WARNING: Flurry of questions about to ensue...

Postby TheMarkster » Fri Aug 17, 2018 3:45 am

Q: What is a topologist? A: Someone who cannot distinguish between a doughnut and a coffee cup.