Several small issues... STP with colors, Map sketch to face

[vern.zimm]

Hi UI folks,

I think the first is likely quite simple. In the Menu Part -> Export CAD... window in Part workbench. I want to always export using "STEP with colors" rather than the default "STEP". Could be change the default in the software to "with colors", because I think... why not? If not, then at least if the "Save as type:" dropdown would remember previous selection, and therefore always stay on "with colors".

Second, possibly something I am doing wrong in workflow, but it's related to having an existing CAD and wanting to modify it or pull dimensions/information using Sketcher. I have the CAD selected in Model tab, click "Create Body" (Part Design -> Create Body) , then "Create Sketch" (Sketch -> Create Sketch, but in Part Design workbench). This brings up the "Base Plane" etc tab in Tasks. I select one, then immediately close the Sketch, and select a face I want to be normal to and use "Map sketch to face..." (Sketch -> Map sketch to face). Can that functionality be built into the "Create Sketch" dialog/task tab?

Okay, facepalm a bit, if you select a specific face before creating a new Sketch, it will map to it. I am still surprised, now that I'm trying different combinations, that there are so many different ways to do it though. I had a custom button bar with Create Body, Create Sketch, Map Sketch to face, so the way I was doing it, I never bothered to click on a specific face, I just selected the whole object in the "Model" tab. Is there some way to make this more simple/direct? Maybe the best option is to do what I was asking previously?

[chrisb]

if you select a specific face before creating a new Sketch, it will map to it.

You should be very careful with this, see the topological naming problem.

[vern.zimm]

For reference:

Code: Select all

OS: Windows 10 Version 2009
Word size of FreeCAD: 64-bit
Version: 0.21.30492 (Git)
Build type: Release
Branch: master
Hash: b4578fb3eae842eb510a1bc055d07d369a67ce94
Python 3.10.6, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.3
Locale: English/United States (en_US)
Installed mods: 
  * Behave-Dark-Colors 0.1.1
  * ProDarkThemePreferencePack 1.0.0

You should be very careful with this, see the topological naming problem.

Indeed, I have run into that. I don't normally have the issue of mapped sketches becoming detached though. Mostly things like when I pull external geometry into a sketch, or when I have used chamfer/fillet.

It would be helpful if, when something is potentially broken due to the naming problem, you can edit each operation in its' previous configuration and map it to the updated base part. For instance, if a Sketch referencing external geometry changes, the Sketch should become invalid. The Sketch features themselves (even the external geometry) do not move from their previous locations. You then have the opportunity to pick the new features that it should be reference to. For chamfer/fillet, it could step through each previous fillet location and allow you to attach it to the new edge (or discard it). It would be a bit like Git, where you have to resolve all of the pending changes before being allowed to add or modify new features. If your change didn't actually cause any problems, you can approve it as-is. It could be a lot of work, but a lot less work than having to scrap the later steps and redo them.

I digress though. I can select the face as I described and my problem is largely resolved.

About the "STEP with colors" default...

[chrisb]

For instance, if a Sketch referencing external geometry changes, the Sketch should become invalid.

That would defeat the whole purpose of parametric modeling. In most cases you want a sketch to follow a change in external geometry. Otherwise you could just use the externals while in sketcher and then remove them.
The problem is, that your computer doesn't know if you want them to follow, or if you want to intervene manually.

[vern.zimm]

That would defeat the whole purpose of parametric modeling. In most cases you want a sketch to follow a change in external geometry. Otherwise you could just use the externals while in sketcher and then remove them.
The problem is, that your computer doesn't know if you want them to follow, or if you want to intervene manually.

I get what you're saying, it would be ideal, but the topological naming problem is a lot of work to keep in order. You have to basically plan out the whole operation of what you will be doing so that you get everything in the right order. If you realize as you are working on it that you need to make a major structural change, you're SOL. I did read in the wiki link about using datum surfaces etc rather than mapping faces. I'm not sure though, can you use external geometry in that case? If you can, wouldn't it be subject to the same problem?

I'm suggesting that the automatic parametric updating be, by default, in semi-auto mode. You could make it a preference that advanced users can disable. When I say semi-auto, I don't mean recreating all of the intermediate steps. I mean that the automatic driven updates that would occur from editing an earlier step are manually processed/approved. Your Sketch is still all there, with no changes. FreeCAD asks you which surface to map it to (or OK the default original surface). If it has external geometry, those, and the live/construction geometries all retain their original layout and constraints. The user would be prompted to verify or update each of the (potentially broken) external geometries before allowing it to "solve" to the new shape.

Similarly, chamfers/fillets would have the user step through each edge and manually re-attach it. Most of the time, the edges/faces are in the same approximate layout (unless you dramatically redesigned the part), they just have a different name. FreeCAD would present you with a view of the old location of that edge, and you just click it again. Maybe you made a pocket 0.100" wider... the new edge will be right there in view, shifted by 0.100" from the old location. It would be click, click, click.

You could have a side-by-side as you are stepping through, where you can see how the original geometry was attached in one view, then choose the appropriate new geometry in the other.

[onekk]

Hi UI folks,
...
I am still surprised, now that I'm trying different combinations, that there are so many different ways to do it though. I had a custom button bar with Create Body, Create Sketch, Map Sketch to face, so the way I was doing it, I never bothered to click on a specific face, I just selected the whole object in the "Model" tab. Is there some way to make this more simple/direct? Maybe the best option is to do what I was asking previously?

Probably you have no knowledge of some simple facts:

• FreeCAD is a project that is more then 20 years old
  See Maybe: https://wiki.freecadweb.org/History
• In the meantime it has expanded and some things have been added
• Some thing are "keep in place" to maintain compatibility with older drawings.
• There are "deprecated ways" of doing things and other that are more modern and robust with regards to TNP:
  https://wiki.freecadweb.org/Topological_naming_problem but also https://wiki.freecadweb.org/Feature_edi ... ble_models

Condensing in few words:

There are correct workflow and some workflow less correct, old and probably deprecated.

Maybe some tour in the Wiki:

https://wiki.freecadweb.org/User_hub

Or maybe even those links:

https://wiki.freecadweb.org/Workarounds

https://wiki.freecadweb.org/Object_name

https://wiki.freecadweb.org/FreeCAD_Man ... pectations

Usually is a matter of having correct documentation.

Hope it helps.

Carlo D.

[vern.zimm]

Probably you have no knowledge of some simple facts:

• FreeCAD is a project that is more then 20 years old
  See Maybe: https://wiki.freecadweb.org/History
• In the meantime it has expanded and some things have been added
• Some thing are "keep in place" to maintain compatibility with older drawings.
• There are "deprecated ways" of doing things and other that are more modern and robust with regards to TNP:
  https://wiki.freecadweb.org/Topological_naming_problem but also https://wiki.freecadweb.org/Feature_edi ... ble_models

Carlo D.

Please understand that I am not saying it's a bad project or software. I use it almost exclusively, even though I have Solidworks 2022 on the same machine. The fact that so many people have continued to work on this project is amazing to me and I appreciate it! If I had some way to help, I would, but I have very little knowledge of programming. I did just sign up as a sponsor after seeing the notice in your post signature. I can do that at least.

[vern.zimm]

@chrisb @onekk Please also look into the export default to STP with colors.
Even if you can just direct me to the code location and I can do research on how it would be done.
(like adrianinsaval did on the other post https://forum.freecadweb.org/viewtopic.php?p=634664)

[chrisb]

Even if you can just direct me to the code location

Sorry, I'm not a coder.

[onekk]

Sorry, I don't know where STP code is located, but from the little I know something is managed by OCCT directly, and there are setting in the preferences to tune things.

Regards

Carlo D.