Rhino BETA Feature: Gumball Control Polygon Alignment

[Joshua_Kennedy]

What is Gumball Control Polygon Alignment?

In the Rhino BETA, the Gumball now has a new Control Polygon alignment mode. In this mode the gumball aligns to the control polygon when control points are selected. This alignment matches the directions used by the MoveUVN panel. When you manipulate the Gumball in Control Polygon alignment, each selected control point moves along its respective control polygon directions or extensions.

To try it out choose the “Align to Control Polygon” option in the gumball menu or by right clicking the gumball button on the status bar. The mode is also accessible through the GumballAlignment command.

Why this new alignment mode?

This new alignment makes it easier to adjust the flow of a surface without constantly switching between the view and a panel. The Gumball’s Control Polygon directions also help maintain G1 continuity between surfaces while adjusting the speed of the transition. The new alignment mode works for surface control points, SubD control points, curve points, and SubD vertex subobject selections.

Selection Behavior:

• The Gumball aligns to the control polygon directions of the most recently selected single control point.

• When you window-select or double-click a row of control points, a base control point for alignment is automatically chosen.

• Moving the control polygon-aligned gumball to another selected control point will realign it.

• If a control polygon alignment cannot be made for the selection then the gumball reverts to object mode alignment.

Movement of control points can also be symmetric while holding the shift key. The axis of symmetry is determined by the direction the control polygon gumball is being moved in. This means when moving control points along the surfaces V direction the control points on the other side in the surfaces V direction move in the opposite direction of the drag. This makes it easy to adjust control points on opposite sides of the surface in the same way.

Movement of control points is proportional to length of the control polygon chord in the direction of the drag:
By holding control (command) the movement distance can be made absolute and all points are moved the same distance.

Control polygon alignment can also be created for selections of SubD control points:
This makes it easier to move SubD control points along the control net. In order for the control polygon alignment to be created for SubD control points all the selected control points must be connected and none of the vertices may be extraordinary.

Working with SoftTransform:
Combining the new ControlPolygon alignment with SoftTransform gives you advanced control over fine-tuning your surface or SubD shapes. Add fallofs and move grips according to a surface’s natural direction.

Note:

• In earlier RhinoWIP builds this happened in Object alignment mode. Object mode no longer aligns to the control polygon.

Let us know what you think!

[Cumberland]

Nice feature. Not related to this but I do wish to see in Rhino9 some native BOM support.

[martinsiegrist]

Nice addition to the gumball. Could this be improved so it also works for meshes and subd?

[Joshua_Kennedy]

If you turn PointsOn for a SubD or mesh and select a control point the gumball will align to its UVN directions. For SubDs and Meshes that’s currently just the normal. I’m guessing you want some UV directions. That’s a bit trickier. Does some other software figure that out correctly for you or how do you expect it to work?

I did find a bug with window select when testing this. I opened RH-88957 to get that addressed.

[Rhino_Bulgaria (Bobi)]

As I mentioned many times in many topics, the Gumball urgently needs secondary “Drag strength” handles, or, alternatively, activating the “Drag strength” speed by dragging/rotating/scaling via the right mouse button instead of the left one.

The 1st approach will automatically bring the “Drag strength” pop-up panel, so that the user could adjust the secondary speed through the slider.

The 2nd approach may do the same, or even can eliminate the need to bring the “Drag strength” window and instead use a preset reduced speed that could be changed from the Gumball options. This will leave a more clean viewport that will not be occupied by the “Drag strength” window. The default secondary drag strength could be anything between 2 and 5. Most of the time, a value of 3 is a good number for fine adjustment.

Since the 2nd approach uses the RMB, there is no need for adding secondary arrow handles to the gumball. The beauty of this approach is that the user is not required to press any icon to activate the drag strength, because he or she just need to press the RMB instead of the LMB. It’s the perfect way to take advantage of a 3d mouse and work fast with the regular mouse.

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Also, check this post to read more about another proposal regarding the Gumball. The user must be able to choose whether the regular Gumball (not in Object mode) will utilize the RMB either as a “Drag strength” function or to temporarily switch to the opposite type of Gumball dragging (smooth or snappy).

Personally, I would love to be able to use the RMB on the regular Gumball for Snappy dragging, whereas the RMB on the new UVN Gumball object mode will use a drag strength with a value of 2 (adjustable from the Gumball’s settings; no need to bring the “Drag strength” pop-up window all the time).
Honestly, the best way to implement both of these functionalities simultaneously is to develop Super Gumball, i.e. Gumball on steroids, so that the users could opt to activate the secondary handles for Move, Rotate and Scale individually. The latter means that the user must have the freedom to activate only the secondary handles for Move, or only for Rotate, or only for Move and Scale. You get the idea. Some users may not like the crowded look of the Super Gumball, this is why it’s essential to offer a way to hide the unnecessary handles.

New Gumball is devastatingly bad. Here are some proposals how to fix it

I challenge the Rhino developers to make a prototype Super Gumball featuring the ideas from this topic and then create a poll in a dedicated topic at the Serengeti section to ask the users whether they prefer the current Gumball or the Super Gumball. Things to consider: Additional gumball handles for Drag strength next to the default handles: [Super Gumball 2] Switching between Snappy dragging and Smooth dragging without the need to reach the keyboard: [Gumball Snappy dragging]

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Also, don’t forget to allow use of “Drag strength” values lower than 1, because the current lower limit prevents a fine adjustment on tiny objects or distant objects. At least make it possible to set a value ot 0,1 or 0,01.

[Joshua_Kennedy]

So I’m 100% with you that drag strength and the gumball don’t play nice together. Having to close the drag strength panel or slide it back to 100 to do a full strength drag, or do any up and down adjustment is tedious and has lots of clicking around. You also don’t know what percentage you need till you start dragging. Unfortunately, I don’t think adding additional handles to the gumball resolves this and would be a bit of a band aid at the cost of making the gumball very cluttered. One thing I’ve thought about, and maybe this is a crazy, is if we hook the drag strength up to the mouses horizontal wheel? So while you’re dragging you can dynamically adjust the strength?

I use a Logitech MX Master 3 and the horizontal scroll wheel is on the thumb. That way as you’re dragging you could adjust the strength using your thumb on that scroll wheel.

[maje90 (Riccardo Majewski)]

@Joshua_Kennedy

For SubDs and Meshes that’s currently just the normal. I’m guessing you want some UV directions.

Not UV directions, but the control polygon directions, which can be just 2 as well as much more than 4 directions.
Please do not forget about SubDs … they really should get more love from McNeel.

If more points are selected, only a single gumball is shown? That seems a bad UI/UX choice.
With the “Show widgets” in the MoveUVN you can have multiple gumballs at once:

Out of 7 points, only 5 are selected, dragging will apply transformation only to those points.
But this needs to have all the gumballs active all the time (indeed, put a limit of… 50 grips? for start…)
(And as Bobi wrote in the other thread, the optional fall-off thing is a must-have..)

Anyway, forget about the MoveUVN command and push all the good stuff on the standard gumball.

Thank you for the good work!

[maje90 (Riccardo Majewski)]

@Joshua_Kennedy

I don’t think adding additional handles to the gumball resolves this and would be a bit of a band aid at the cost of making the gumball very cluttered.

(RH8) yes, it’s already enough…

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About the fall-off thing, maybe adding a toggle for “fall-off” on the bottom control:

with something like:

(from Meshmixer, default “no-falloff” should be the first, default “falloff active” should be the second one… imo)

[Joshua_Kennedy]

@maje90

If more points are selected, only a single gumball is shown? That seems a bad UI/UX choice.
With the “Show widgets” in the MoveUVN you can have multiple gumballs at once:

We had lots and lots of problems with cluttered display, widget size, and picking when dealing with large selections on dense surfaces.

@maje90

Not UV directions, but the control polygon directions, which can be just 2 as well as much more than 4 directions.

Keeping those directions consistent is the tricky part and it falls apart very quickly if there are more than four edges. Do you have an example of this working elsewhere or what you expect to happen in Rhino I can take a look at?

[maje90 (Riccardo Majewski)]

@Joshua_Kennedy

We had lots and lots of problems with cluttered display, widget size, and picking when dealing with large selections on dense surfaces.

Is manually moving the gumball every time a good solution? Imho not.
Make a limit for that, over 100? 50? grips, then show just one. But when you select a bunch of grips, it should totally be doable. Please…

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@Joshua_Kennedy

Keeping those directions consistent is the tricky part and it falls apart very quickly if there are more than four edges.

I feel you!
I personally tried myself doing so, the hard part for me was the total lack of SubD topology (with meshes it’s SO much simpler…) SubD were totally un-manageable from rhinocommon… but it was months ago!
I really hope and expect there will be good news about this matter.

@Joshua_Kennedy

Do you have an example of this working elsewhere or what you expect to happen in Rhino I can take a look at?

As someone that works and live with Rhino, no.
But it’s 2025, and I expect other software have this function at least from… 20 years ago?
I did make a video with some example:

WISH: specialized gumball for control points

Hi all. Working with SubD, etc etc… [2023-06-01 13_24_58-ScreenToGif - Editor] When selecting a control point (or “grip”), the option “Align to Object” is limited to having Z (blue) gumball axis/arrow aligned to local normal and Y (green) arrow aligned to local V direction (if it is a surface). What about Mesh/SubD? " … just align the blue arrow to vertex normal and we are good to go!" [2023-06-01 13_26_33-Untitled - Rhino 7 Commerciale - Perspective] … This is what we coul…

This should’ve been a feature for Rhino 8 on release day… arguably even since 7’s…

You can do it!
Pretty please!

[martinsiegrist]

I saw the normal on a SubD vertex.

Regarding other software, I don’t use any but I think someone posted an example some time ago of a SubD model where a vertex was possible to drag along the edges.

[morg]

Just a thought: look at softimage, the best modeling interface to have ever existed. It was always fast, easy to understand and switching from points to spans and adding and subtracting from selections was a no brainer. All with no stupid gumball crapping up the screen.

[René_Corella]

@Joshua_Kennedy

Selection Behavior:

• The gumball will align to the UVN directions of the first control point selected.
• Additional control point selections will not update the gumball alignment.

@Joshua_Kennedy May I ask why this is the case? Honest question. Thank you for this awesome feature update.

[Vanessa (Vanessa K Waale)]

Hi @René_Corella - The Gumball arrows will align to the UVNs of the first control point selected. If you select additional points, the Gumball won’t change, since it’s still positioned on that initial selected ctrl pt, however, dragging the arrows (located on the first ctrl pt), will move each point in its own UV direction.

Does that answer your question?

[Rhino_Bulgaria (Bobi)]

@morg

softimage

You are comparing a 3d mesh modeling program with NURBS modeling program where a fine tuning of control points in the microns range is essential. This is the reason why “Drag strength” is needed in NURBS modeling programs. This is not the case with the 3d mesh programs.

These UVN handles sometimes are moved with normal speed, other times with “Drag strength” speed, meaning that both types of arrow handles must be visible simultaneously for an instant access.

The distance between the normal handles and drag strength handles should be adjustable from the options. A value of 0 will turn off the drag strength handles.

[René_Corella]

Hi @Vanessa, thank you for responding.

@Vanessa

Does that answer your question?

Not yet; however, it’s my fault and didn’t explain myself. I was genuinly interested in knowing the reason(s) behind that particular part of the gumball behavior.

*Edit:
I guess I can answer my own question (kind of, partially) after all by comparing with the Fusion360 form-editing manipulator.

Here three points of the “SubD control polygon” are selected together and the manipulator is automatically at the center point of this selection, but that’s because the selection filter is set to “selection space”:

If I switch to the filter “Local per entity”, then things look like this new UVN Gumball feature, where the manipulator remains on the first selected vertex:

Then the actual geometry deformations are different, so it all makes sense.

I guess the reason behind this behavior doesn’t matter anymore because in Rhino WIP I can just make sure my first selected point is ‘the center one’ when possible

Thanks for such awesome upgrades!

[C_Morgan_Boyes]

I guess you are completely unfamiliar with Softimage. It was NURBS. It had the same precision as Alias did at the time. It also had an interface that was user friendly and organized, unlike Alias. It had soft selections and ways to move NURBS points relative to the surface and globally, singlely and in groups, very intuitively AND with increment adjustability using all three mouse buttons and toggles within the interface.

FYI, It didn’t even have support for polygon modeling until later in it’s life.

The point is that before everyone got on the stupid gumball bandwagon there were better ways to modify and move NURBS points.

[Rhino_Bulgaria (Bobi)]

Your guess about me is wrong. XSI was primarily used for polygonal modeling in the film industry, video games industry, etc, note than 20 years ago. It had a Gumball. Its NURBS capabilities were super bad. The only other program with worse NURBS capabilities was 3ds Max. Both were not good for NURBS modeling.

Alias relies on using 3 mouse buttons, so button is assigned to moving the objects in one of the main directions: XYZ for objects and UVN for control points.