I was playing with dimensions and encountered a problem dimensioning the radius of the edge of a solid.

Steps I took:
1) Draw solid box
2) Draw solid sphere overlapping box
3) Boolean Diff, with sphere as cutting object
4) DimRadius one of the arc edges that the sphere cut

DimRadius command runs but doesn't display an arrow or center point. Clicking on Arrow location and Text location doesn't produce a radius dimension.

Thinking it was due to this being an edge, I selected the edge and copy/paste to create a curve and then tried DimRadius the curve, same results. Am I doing something wrong, or have I stumbled upon a bug? Model attached.

--Larry

I would say that neither the edge curve, nor the curve from copying the edge curve, are being recognized as a circular arc.

A new arc draw over top of the edge is recognized as a curcular arc, and the dim arc works fine.

Cannot remember all of the new curve methods...is a line, is an arc (?), is open, is closed, etc... to see how the curve is ID'd.
How does MoI know if a curve is an arc?

- Brian

Hey Michael, thank you for the awesome additions! Also, congrats on a squeaky-clean to-do list! This must be a rare state for you :))

moi.ui.getLastOrientationPickerFrame() <- Is this what I think it is? *rubs eyes with excitement*

Can't wait to try this version out. Much love!

Hi Brian,

Indeed, neither the edge nor curve that resulted from copy/paste of the edge are arcs:

The edge's Details are: Open edge, Joined, Planar

The pasted curve's details are: Open curve, Planar, 1 segment

And a real arc's details are: Open curve, Arc, Planar, 1 segment

From the API perspective I believe the relevant properties are isCircle and isArc.

Odd though that a boolean diff with a sphere as cutting object wouldn't have left an arc behind but I suppose it depends upon the object being cut.

> How does MoI know if a curve is an arc?

It's Halloween, so it must just be magic... ;-}

--Larry

:-)
Awaiting Michaels response.

- Brian

Hi Larry, yes that's not really a bug in the dimensions, it's like Brian writes above that the edges are not being recognized as arcs.

Currently MoI looks at a curve and in order to be recognized as an arc it must have the same curvature (within a very tight tolerance of 0.0000000001 units) at 10 points sampled along it.

Meanwhile the result of the boolean is calculated at an intersection tolerance of 0.001 units. So this mismatch between the "is it an arc" tolerance and the "surface/surface intersection tolerance" is one problem.

But also there is a mechanism that does special case intersections between analytic shapes to get higher precision. However, I have disabled the sphere/plane analytic intersector back a long time ago though because of some bugs in it.

It's pretty risky to modify either the tolerance or the surface/surface intersector right at the end of the beta cycle, so this is something that I can look at fixing in v5 once that is underway.

- Michael

Hi nameless,

re:
> moi.ui.getLastOrientationPickerFrame() <- Is this what I think it is? *rubs eyes with excitement*

Yes, this is the piece that should make it possible to make a plugin that does scaling after positioning an imported object. I'll see if I can set it up.

- Michael

Just a thought, maybe off-base and not important:
To assist in the dimensioning of curves that look like arcs, but are out of current MoI tolerance testing range,
a small user ran script might be able to test a single arc-like curve, for planarity and arc-ness, with a broader tolerance,
and respond with a radius value, or "not an arc" message? User could add a regular leader with ØR...

https://wiki.mcneel.com/developer/sdksamples/classifycurve

- Brian

re: Box / Sphere boolean dimensioning - well analytic intersections are active for plane/plane, plane/cone, plane/cylinder, and plane/torus but not plane/sphere. I seem to remember the problem was that it didn't handle a partial sphere surface instead of a full sphere.

I can dig into it more in v5.

- Michael

Congratulations! MoI is awesome. It totally changed my technical modeling approach! Thanks for this amazing software.

Hi Michael,

Thanks for the additional insights into how MoI works, always interesting to read your explanations. I'm totally fine with waiting for the v5 cycle for changes in more critical areas, my joy in using MoI will not be diminished by this little quirk!

--Larry

Hi Michael,

Re: arrow gaps

My initial question about the arrow gaps was spawned by my not particularly liking how the arrow tips extended beyond or overlapped the object being referred to. I have since been experimenting with the arrowGap properties you've shown and see that they do indeed work nicely to address this personal preference. The fact that they are a preset makes them especially flexible, particularly if someone wanted to mix differing styles in the same drawing. It would be nice to see these exposed in the preset UI.

While I was experimenting, I also found the discussion about mitered tips of the arrowheads http://moi3d.com/forum/index.php?webtag=MOI&msg=9363.86, so now I see that MiterArrowheads=n is another way to meet this preference. Though since this behaves globally it does not seem to be quite as flexible as the arrowGap properties are.

Since you've indicated that the arrowGap properties may not be as difficult to work with in the future, I would vote for keeping both methods (arrowGap and MiterArrowheads) available in MoI and exposing the arrowGap properties in the UI. If arrowGap turns out to be a problem I'd be perfectly happy with only MiterArrowheads=n.

--Larry

Great Lino you are every where! Yeah Moi3D is awesome..

Hi Larry, I'm glad the arrow gap setting is useful!

Re: MiterArrowheads=n , (http://moi3d.com/forum/index.php?webtag=MOI&msg=9363.86)

The MiterArrowheads moi.ini setting only has an impact on the viewport display inside of MoI, it doesn't affect PDF/AI file content.

Closed arrowheads in the PDF/AI content are not mitered because they have only a fill set for rendering their paths, not a fill + stroke. So for closed arrowheads, there isn't any piece of it that extends further than the tip point.

It's difficult to make the same thing happen on screen vs in PDF file because the screen has a far more limited resolution to work with.

- Michael

Hi nameless,

re: moi.ui.getLastOrientationPickerFrame()

So yes this piece should now allow a script to be created that does an "ImportPart" (right click on File > Import) or "PastePart" function (Ctrl+Shift+V) which positions the inserted objects to also scale the object by the proper origin point as an additional step.

I've attached a try at making those here, these versions "ImportPartWithScale", and "PastePartWithScale" should include a scaling step after the positioning. Hope that is close to what you were thinking of.

- Michael

Michael,

This is stellar... I can't believe you made this happen so quickly. For me, asset placement is solved with the most elegant/intuitive way.

Thank you so much for keeping your eyes on MoI user needs and for helping us tirelessly. It's so inspiring!!!

Hi nameless, you're welcome! Through e-mail you asked if this could be used in the CustomUI object library. I think that should work ok, you would edit the file ObjLibrary.menu.htm on line #26:

			else { moi.command.execCommand( 'importpart '+file); }

Make that say importpartwithscale instead, but take care not to accidentally remove the space that is after it.

- Michael

Perfection!

Hi Michael,

thanks for more details regarding "4views" project.

re:
>So I mean more like this - you have your model you've made in one file, and a title block template set up in a separate file. Now go ahead and add in dimensions on your model. Then you export to PDF and there is an option for the view configuration. It would have options for "Top", "Front", "Right", "3D" (all single view drawings as it is now), "4 views", or "Use title block template".

If I understand it correctly I make dimensioning on model (part) in all required views in one file, let say in MOI Split view, which is similar to 4 view projection. That's fine.

Only two questions:

.: Would it be possible to "turn off" unusable/invisible dimensions in given view and in 3D view? I mean dimensions marked by white arrow.



.: Would it be possible to specify before export First-angle projection or Third-angle projection (https://en.wikipedia.org/wiki/Multiview_projection)? I mean for example Top, Front, Right and 3D view in specific order given by ANSI or ISO standards, pls see bellow.



Thanks a lot.
Mik

BTW:

ImportPartWithScale is very useful script, only as a reminder for me, that Import Icon has two different options, I've reworked ImportIcon.png and copied to c:\Program Files\MoI 4.0 beta Oct-27-2020\ui\icons\ImportIcon.png




Mik